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Heavy metal pollution in soil has emerged as a major environmental concern. This can be attributed to human activities such as mining, modern agriculture, and industrialization. This study was conducted to determine how heavy metals spread from mine tailings to surrounding farmland. Metal absorption and accumulation were also investigated in the root and shoot biomass of tapioca crops grown in those farmlands. Metal concentrations in MTAS1 were 85.3 ± 1.2, 45.8 ± 1.5, 134.8 ± 1.7, 92.4 ± 2.2, and 78.95 ± 1.4 mg kg-1, respectively. Heavy metal concentrations in MTAS2 and MTAS3 were found to be 79.62 ± 1.6, 75.4 ± 1.5, 41.31 ± 1.1, 47.8 ± 1.6, 142.5 ± 2.1, 128.4 ± 1.4, 86.2 ± 1.9, 79.5 ± 1.3, and 83.4 ± 1.2 mg kg-1, respectively. Tapioca crop shoot and root biomass grown at these metal polluted sites absorbed and accumulated significant amounts of Cd, Cu, Zn, Pb, Ni, and Mn. Notably, the metal content of the tapioca crop's root and shoot biomass exceeded national standards. • Magnesite mine tailings dumped surrounding sites were polluted with heavy metals. • MTAS1, MTAS2, and MTAS3 farmland site was polluted with Cd, Cu, Zn, Pb, Ni, and Mn. • Root and shoot biomass of tapioca absorbed and accumulated these metals from polluted soil. • The metal was transferred from root to shoot of tapioca crop. [ABSTRACT FROM AUTHOR]

Penthiopyrad (PEN) is a novel fungicide as succinate dehydrogenase inhibitor (SDHI) with chiral characteristics, and it is crucial to investigate its enantioselective residue behavior given its extensive application. This study aimed to comprehensively evaluated the storage stability, deposition, dissipation, accumulation, and dietary risk associated with PEN enantiomers and its metabolite 1-methyl-3-trifluoromethyl-1 H-pyrazole-4-carboxamide (PAM) in apple and strawberry. Two enantiomers of PEN accumulated primarily on leaves after spraying, whose concentrations were much higher than those observed in the apple and strawberry fruits, respectively. S -(+)-PEN was found to be preferentially degraded in apples (EF: 0.5113–0.5925), resulting in a relative enrichment of its antipode. Multiple sprays of PEN led to the accumulation of both of its enantiomers, with average residue accumulation value (RA average) of 1:2.06:1.11 for the R -(−)-PEN and 1:2.06:1.09 for the S -(+)-PEN in strawberries, respectively. The terminal residues of PAM were lower than the limit of quantification (LOQ), and that of total PEN in both fruits were below the maximum residue limit (MRL) established by China. Furthermore, the acute risk quotient (RQa) of target pesticide in apples were 0.821 %–2.105 %. The investigation provided a theoretical foundation and scientific guidance for applying PEN at the enantiomeric level in fruits. [Display omitted] • The penthiopyrad (PEN) enantiomers are mainly distributed on leaves 2 h after foliar spraying. • PEN exhibits enantioselective degradation in apples with S -(+)-PEN preferential degradation. • Repeated spraying of PEN could lead to residual accumulation in strawberries. • The acute dietary exposure risk quotient of PEN in apples was comparably acceptable. [ABSTRACT FROM AUTHOR]

The prevalence of inorganic pollutants in the environment, including heavy metals (HMs), necessitates a sustainable and cost-effective solution to mitigate their impacts on the environment and living organisms. The present research aimed to assess the phytoextraction capability of spinach (Spinach oleracea L.), under the combined effects of ascorbic acid (AA) and microwave (MW) irradiation amendments, cultivated using surgical processing wastewater. In a preliminary study, spinach seeds were exposed to MW radiations at 2.45 GHz for different durations (15, 30, 45, 60, and 90 seconds). Maximum germination was observed after the 30 seconds of radiation exposure. Healthy spinach seeds treated with MW radiations for 30 s were cultivated in the sand for two weeks, after which juvenile plants were transferred to a hydroponic system. Surgical industry wastewater in different concentrations (25 %, 50 %, 75 %, 100 %) and AA (10 mM) were provided to both MW-treated and untreated plants. The results revealed that MW-treatment significantly enhanced the plant growth, biomass, antioxidant enzyme activities and photosynthetic pigments, while untreated plants exhibited increased reactive oxygen species (ROS) and electrolyte leakage (EL) compared with their controls. The addition of AA to both MW-treated and untreated plants improved their antioxidative defense capacity under HMs-induced stress. MW-treated spinach plants, under AA application, demonstrated relatively higher concentrations and accumulation of HMs including lead (Pb), cadmium (Cd) and nickel (Ni). Specifically, MW-treated plants with AA amendment showed a significant increase in Pb concentration by 188 % in leaves, Cd by 98 %, and Ni by 102 % in roots. Additionally, the accumulation of Ni increased by 174 % in leaves, Cd by 168 % in roots, and Pb by 185 % in the stem of spinach plant tissues compared to MW-untreated plants. These findings suggested that combining AA with MW irradiation of seeds could be a beneficial strategy for increasing the phytoextraction of HMs from wastewater and improving overall plant health undergoing HMs stress. [Display omitted] • Low level microwave (MW) radiations increased seed germination and growth of spinach. • Surgical industrial wastewater differentially affected the growth of MW treated and untreated spinach. • Ni, Cd and Pb concentrations increased in spinach with increasing concentrations of surgical wastewaters. • Ascorbic acid improved the physiology and biochemistry of MW treated and untreated spinach. • Ascorbic acid increased Ni, Cd and Pb accumulation in both MW treated and untreated spinach grown under wastewater. [ABSTRACT FROM AUTHOR]

The mineral composition of wild-growing mushroom species is influenced by various environmental factors, particularly the chemical properties of the soil/substrate. We hypothesised that element uptake might also correlate with taxonomic classification, potentially allowing us to predict contamination levels based on mushrooms within the same taxonomic rank. This study compared the mineral composition (Ag, As, Ba, Ca, Cd, Co, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Se, and Zn) of 16 saprotrophic mushroom species from 11 genera across 4 families and 2 orders. Among these were 13 edible and 3 inedible mushrooms, all collected from natural, wild stands in a forest in central-western Poland between 2017 and 2020. Phallus impudicus exhibited the highest mean content of Ba (together with Phallus hadriani) (6.63 and 8.61 mg kg−1, respectively), Ca (with Paralepista gilva and Stropharia rugosoannulata) (803, 735 and 768 mg kg−1, respectively), Cd (with Lycoperdon perlatum) (3.59 and 3.12 mg kg−1, respectively), Co (0.635 mg kg−1), and Fe (with P. hadriani and S. rugosoannulata) (476, 427 and 477 mg kg−1, respectively), while Macrolepiota mastoidea showed the highest content of Ag (1.96 mg kg−1), As (with Coprinus comatus) (1.56 and 1.62 mg kg−1, respectively) and Cu (with Macrolepiota procera and Chlorophyllum rhacodes) (192, 175 and 180 mg kg−1, respectively). Comparing the content of the analysed elements in the genera represented by at least two species, a similarity was observed, the same as the mean concentration in soil under these species. Soil characteristics could be a superior factor that overshadows the impact of the mushroom genus on the elements accumulation, obscuring its role as a determinant in this process. The results are not definitive evidence that belonging to a particular taxonomic rank is a prerequisite condition affecting the accumulation of all elements. A closer focus on this issue is needed. [Display omitted] • Mineral composition of 16 mushroom species in 2 taxonomic orders was examined. • Taxonomic rank may affect mushroom physiology expressed in uptake of elements. • Discriminative taxonomic rank may be mostly mushroom genus, sometimes the species. • Mineral profile of mushrooms depends on chemical characteristics of soil. • Chosen mushroom species contain high amounts of K and Mg and possibly As and Cd. [ABSTRACT FROM AUTHOR]

The environmental burden of organic micropollutants has been shown in aquatic ecosystems, while trophic fate of many compounds in terrestrial food chains remains highly elusive. We therefore studied concentrations of 108 organic micropollutants in a common European mammal, the bank vole (Clethrionomys glareolus), and 82 of the compounds in a specialized predator, Tengmalm's owl (Aegolius funereus) relying to >90 % on voles as its prey. We studied compounds in whole voles (n = 19), pools of 4–8 bank voles (n pools = 4), owl blood (n = 10) and in owl eggs (n = 10) in two regions in Sweden. For comparison, we also included previously published data on 23 PFAS (per- and polyfluoroalkyl substances) in bank vole liver (n pools = 4) from the same regions. In voles, concentrations of the organic micropollutants caffeine (max Individual 220 ng/g ww) and DEET (N,N-diethyl-m-toluamide) (max Pool 150 ng/g ww) were 2–200 times higher in voles relative to owl blood and eggs. Conversely, concentrations of nicotine, oxazepam, salicylic acid, and tributyl citrate acetate were 1.3–440 times higher in owls. Several PFAS showed biomagnification in owls as revealed by maximum biomagnification factors (BMFs); PFNA (perfluorononanoate) BMF = 5.6, PFTeDA (perfluorotetradecanoic acid) BMF = 5.9, and PFOS (perfluorooctane sulfonate) BMF = 6.1. Concentrations of organic micropollutants, alongside calculated BMFs, and Tengmalm's owl's heavy reliance on bank vole as staple food, suggest, despite small sample size and potential spatio-temporal mismatch, accumulation of PFAS (especially PFNA, PFTeDA, and PFOS) in owls and biomagnification along the food chain. Concentrations of PFAS in owl eggs (e.g., 21 ng/g ww PFOS) highlight the likely pivotal role of maternal transfer in contaminant exposure for avian embryos. These concentrations are also of concern considering that certain predators frequently consume owl eggs, potentially leading to additional biomagnification of PFAS with yet undetermined consequences for ecosystem health. [Display omitted] • Several OMPs biomagnify from bank voles to Tengmalm's owls. • PFOS (perfluorooctane sulfonate) showed max biomagnification factor of 6.1. • Maternal transfer likely important in contaminant exposure for avian embryos. • Unknown fitness consequences for egg predators. [ABSTRACT FROM AUTHOR]

The accumulation of heavy metal(loid)s (HMs) in soil-grown mushrooms poses potential health risks. Morchella sextelata (black morel) is a typical soil-grown mushroom with a rapidly expanding cultivation area. This study investigated the distribution of arsenic, cadmium, chromium, copper, mercury, nickel, lead, and zinc in 213 pairs of soil and morel samples collected from 29 provincial administrative regions in China, together with the nutritional contents in the morel samples. The HM contents in the arable soils used to cultivate morels were 2.4–33.1 times higher than those in desert soils, while the HM contents in arable-soil morels were 2.9–155.9 times higher than desert morels. The HM contents of morels and their cultivation soils were significantly correlated (0.465 ≤ R ≤ 0.778, P < 0.001). Furthermore, the enrichment factors of most HMs were higher in arable soils than in desert soils (P < 0.05), except Hg. A considerable proportion of the arable soils produced morels with HMs exceeding the risk control standards (RCSs) for food and the health-risk thresholds of dietary intake. In comparison, HMs in morels from desert soils were far below the RCSs and health-risk thresholds. In addition, desert morels contained higher contents of crude proteins, total polysaccharides, and free amino acids (P < 0.001). These findings indicate that growing morels in desert soils is a way of green production that provides mushroom products with improved safety and nutrition. [Display omitted] • Arable soils had higher HM contents than desert soils. • M. sextelata in arable-soils had higher enrichment factors of HMs than in deserts. • Accumulation of HMs in morel ascocarps showed positive correlations with SOC. • Desert M. sextelata had lower health risks and higher nutritional quality. • M. sextelata cultivation in deserts has stable productivity and high economic profit. [ABSTRACT FROM AUTHOR]

The efficient use of pesticides has long been a topic of public concern, necessitating a thorough understanding of their movement in plants. This study investigates the translocation and distribution of penthiopyrad in pakchoi plants cultivated both in hydroponic and soil-cultivated conditions. Results indicate that penthiopyrad predominantly accumulates in the roots, with concentrations of 11.3–53.9 mg/kg following root application, and in the leaves, with concentrations of 2.0–17.1 mg/kg following foliar application. The bioconcentration factor exceeded 1, with values ranging from 1.2 to 23.9 for root application and 6.4 to 164.0 for foliar application, indicating a significant role in the absorption and accumulation processes. The translocation factor data, which were <1, suggest limited the translocations within pakchoi plants. The limitation may be attributed to the hydrophobic properties of penthiopyrad (log K ow = 3.86), as evidenced by its predominant distribution in the subcellular solid fractions of pakchoi tissues, accounting for 93.1% to 99.5% of the total proportion. Six metabolites (753-A-OH, M12, 754-T-DO, M11, PCA, and PAM) were identified in this study as being formed during this process. These findings provide valuable insights into the absorption, translocation, and metabolism of penthiopyrad in pakchoi. [Display omitted] • Penthiopyrad was absorbed and accumulated by its application site on pakchoi. • Uptake and downward translocation of penthiopyrad were limited by pakchoi. • Uptake of penthiopyrad was active by pakchoi roots and passive by pakchoi leaves. • Penthiopyrad mainly existed in the cell walls of pakchoi due to its hydrophobicity. • Six potential metabolites of penthiopyrad were proposed in pakchoi. [ABSTRACT FROM AUTHOR]

Chlorinated paraffins (CPs) in poultry feed and the farm environment might bioaccumulate in poultry eggs. Unlike chickens, which are mostly raised in cages, ducks are commonly raised free range. This would expose ducks to CPs in the environment. However, information on the presence of CPs on duck farms is scarce. In the present study, samples of duck eggs, duck feathers, poultry feed, and soil were collected from 25 duck farms in South China. Forty-eight congener groups of short- and medium-chain CPs (SCCPs and MCCPs) were detected in the samples. Interestingly, relatively high concentrations of SCCPs and MCCPs were found in the duck feathers. The median concentrations of SCCPs and MCCPs in the duck eggs, feathers, feed and soil were: 46 and 18 ng/g wet weight, 2460 and 992 ng/g, 103 and 47 ng/g, and 24 and 10 ng/g dry weight, respectively. The dominant groups of SCCPs and MCCPs were C 10 Cl 6–7 and C 14 Cl 7–8 , respectively. The close relationship between duck feathers and poultry feed indicated that the duck feathers might act as a bioindicator for the exposure of ducks to CPs. The margin of exposure approach was used to assess the health risk, with the results showing that the consumption of duck eggs posed a low risk to different age groups from exposure to SCCPs and MCCPs. [Display omitted] • Higher concentrations of CPs were found in duck feathers than eggs, feed and soil. • The dominant CPs had short carbon chains and low levels of chlorine. • There was a close relationship between CPs in the feathers and feed. • The human exposure risk to CPs through duck egg consumption was low. [ABSTRACT FROM AUTHOR]

Alkanotrophic Rhodococcus strains from the Regional Specialised Collection of Alkanotrophic Microorganisms (acronym IEGM, www.iegmcol.ru) were screened for accumulation and sorption of MoO 4 2- ions. Morphological and ultrastructural changes observed in bacterial cells during their cultivation in the molybdenum-containing medium are described. The species peculiarities, growth substrate preferences, and other physiological features allowing for the efficient removal of molybdate ions from the culture medium are discussed. Bioinformatics analysis of genes and proteins responsible for resistance to and accumulation of molybdenum was carried out using the sequenced R. ruber IEGM 231 and other published Rhodococcus genomes. n -Hexadecane growing strains with high (up to 85 %) accumulative activity and resistance to elevated (up to 20.0 mM) molybdenum concentrations were selected, which can be used for bioremediation of environments co-contaminated with heavy metals and hydrocarbons. Transmission electron microscopy and energy dispersive X-ray spectroscopy (TEM-EDX) revealed the ability of Rhodococcus not only to accumulate, but also to chemically convert soluble toxic molybdenum into insoluble compounds detected in the form of electron-dense nanoparticles. • Alkanotrophic Rhodococcus actively accumulate molybdenum ions. • Mo accumulation leads to changes in cellular ultrastructure and physiology. • High concentrations of Mo ions suppress the respiratory activity. • Rhodococcus can be used for Mo-containing wastewater treatment. [ABSTRACT FROM AUTHOR]

Neonicotinoids (NNs) are commonly used pesticides that have a selective agonistic action on insect nicotinic acetylcholine receptors. Recent evidence has shown that NNs have adverse effects in the next generation of mammals, but it remains unclear how NNs transferred from dams to fetuses are distributed and accumulated in fetal tissues. Here, we aimed to clarify the tissue distribution and accumulation properties of the NN clothianidin (CLO) and its 6 metabolites in 7 tissues and blood in both dams and fetuses of mice administered CLO for a single day or for 9 consecutive days. The results showed that the total concentrations of CLO-related compounds in the brain and kidney were higher in fetuses than in dams, whereas in the liver, heart, and blood they were lower in fetuses. The multi-day administration increased the total levels in heart and blood only in the fetuses of the single administration group. In addition, dimethyl metabolites of CLO showed fetus/dam ratios >1 in some tissues, suggesting that fetuses have higher accumulation property and are thus at higher risks of exposure to CLO-related compounds than dams. These findings revealed differences in the tissue-specific distribution patterns of CLO and its metabolites between dams and fetuses, providing new insights into the assessment of the developmental toxicity of NNs. • Distribution and accumulation of neonicotinoid clothianidin (CLO) were evaluated. • CLO and its 6 metabolites in both dam and fetus tissues were measured. • Total concentrations in brain and kidney were higher in fetuses than in dams. • Dimethyl metabolites of CLO showed fetus/dam ratios >1 in some tissues. • Fetuses are at higher risks of exposure to CLO-related compounds than dams. [ABSTRACT FROM AUTHOR]

Seagrass beds are susceptible to deterioration and heavy metals represent a crucial impact factor. The accumulation of heavy metal in two tropical seagrass species were studied in South China in this study and multiple methods were used to identify the heavy metal sources. E. acoroides (Enhalus acoroides) and T. hemperichii (Thalassia hemperichii) belong to the genus of Enhalus and Thalassia in the Hydrocharitaceae family, respectively. Heavy metal concentrations in the two seagrasses followed the order of Cr > Zn > Cu > Ni > As > Pb > Co > Cd based on the whole plant, and their bioconcentration factors were 31.8 ± 29.3 (Cr), 5.7 ± 1.3 (Zn), 7.0 ± 3.8 (Cu), 3.0 ± 1.9 (Ni), 1.2 ± 0.3 (As), 1.7 ± 0.9 (Pb), 9.1 ± 11.1 (Co) and 2.8 ± 0.6 (Cd), indicating the intense enrichment in Co and Cr within the two seagrasses. The two seagrasses were prone to accumulate all the listed heavy metals (except for As in E. acoroides), especially Co (BCFs of 11 24) and Cr (BCFs of 26 89) in the aboveground parts, and the belowground parts of both seagrasses also accumulated most metals (BCFs of 2 7) excluding Co and Pb. The Pb isotopic ratios (mean 208Pb/204Pb, 207Pb/204Pb and 206Pb/204Pb values of 38.2054, 15.5000 and 18.3240, respectively) and Cd isotopic compositions (δ114/110Cd values ranging from –0.09‰ to 0.58‰) within seagrasses indicated the anthropogenic sources of Pb and Cd including coal combustion, traffic emissions and agricultural activities. This study described the absorption characteristics of E. acoroides and T. hemperichii to some heavy metals, and further demonstrated the successful utilization of Pb and Cd isotopes as discerning markers to trace anthropogenic origins of heavy metals (mainly Pb and Cd) in seagrasses. Pb and Cd isotopes can mutually verify and be helpful to understand more information in pollution sources and improve the reliability of conclusion deduced from concentrations or a single isotope. • Metals were prone to accumulate in above- than belowground parts of segrasses. • Leaves of the two seagrasses could be the bioindicators for Co and Cr. • Metals in seagrasses were the combination of natural and anthropogenic sources. • Anthropogenic sources had coal combustion, traffic emission and rural activities. • Combination of Pb & Cd isotopes was a potent tool to trace heavy metal sources. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination in paddy soil threatens rice growth and food safety, enriching manganese (Mn) in rice seedlings is expected to reduce Cd uptake by rice. The effects of 250 μM Mn-treated seedlings on reducing Cd uptake of four rice genotypes (WYJ21, ZJY1578, HHZ, and HLYSM) planted in 0.61 mg kg−1 Cd-contaminated soil, were studied through the hydroponic and pot experiments. The results showed that the ZJY1578 seedling had the highest Mn level (459 μg plant–1), followed by WYJ21 (309 μg plant–1), and less Mn accumulated in the other genotypes. The relative expression of OsNramp5 (natural resistance-associated macrophage protein) was reduced by 42.7 % in ZJY1578 but increased by 23.3 % in HLYSM. The expressions of OsIRT1 (iron-regulated transporter-like protein) were reduced by 24.0–56.0 % in the four genotypes, with the highest reduction in ZJY1578. Consequently, a greater reduction of Cd occurred in ZJY1578 than that in the other genotypes, i.e., the root and shoot Cd at the tillering were reduced by 27.8 % and 48.5 %, respectively. At the mature stage, total Cd amount and distribution in the shoot and brown rice were also greatly reduced in ZJY1578, but the inhibitory effects were weakened compared to the tillering stage. This study found various responses of Cd uptake and transporters to Mn-treated seedlings among rice genotypes, thus resulting in various Cd reductions. In the future, the microscopic transport processes of Cd within rice should be explored to deeply explain the genotypic variation. [Display omitted] • High Mn cultivation resulted in various Mn accumulation in different rice genotypes. • Mn induced various inhibitions on OsNramp5 and OsIRT1 expression among rice genotypes. • Cd uptake and transport within rice were depressed variously by Mn among genotypes. • Mn induced a lower Cd reduction at the mature than that at the tillering stage. [ABSTRACT FROM AUTHOR]

The content of gadolinium (Gd) is continuously increased in environment, which potentially threatens human health and ecological equilibrium. However, the phytotoxicity of Gd on plants remains unknown until now. In this study, the accumulation, distribution, and chemical forms of Gd as well as its influence on growth and nutrient balance were systematically studied in rice seedlings after the treatments of different concentrations of Gd (0, 1, 10, 100, and 1000 μM) for 10 days. The results showed that most Gd was accumulated in the roots and only a little percentage of Gd was transported to shoots. The accumulation of Gd was increased in a dose-dependent manner in various chemical forms and subcellular fractions. More than 80% of Gd was in the forms of insoluble oxalates and phosphates. Gd was mainly compartmentalized in the cell wall, and the content of Gd was increased with increasing concentrations of Gd. In addition, hormetic effects of Gd were found on rice growth. The growth of rice was induced by the lower concentration of Gd, but inhibited by the higher concentration of Gd. The results indicated that rice seedlings could cope with Gd toxicity through cell wall compartmentalization as well as forming of precipitates with oxalate and phosphate. Image 1 • The subcellular distribution of Gd was investigated in the rice seedings. • The chemical forms of Gd and accumulation were investigated in the rice. • The distribution characteristics of Gd was investigated in the rice seedings. • Gd tolerance was related to the subcellular distribution and chemical forms. [ABSTRACT FROM AUTHOR]

Cu and Zn are hyper-accumulated in oysters, and the accumulation of these metals increases host resistance to pathogens. However, the role of Cu/Zn in oyster immune defense remains unclear. In this study, Crassostrea angulata with different levels of Cu and Zn were obtained through metal exposure or selective breeding. Both in vivo and in vitro experiments showed that oysters accumulating more Cu/Zn exhibited stronger antibacterial abilities. Vibrio harveyi infection significantly promoted the metal redistribution in oysters: Cu and Zn concentrations decreased in the mantle, but increased in the plasma and hemocytes. This redistribution was accompanied by changes in the expression levels of Cu and Zn transporter genes (CTR1, ATP7A, ZIP1, and ZNT2), suggesting that the Cu/Zn burst observed in the hemocytes was likely due to the transfer of heavy metals from plasma (mediated by the metal importer proteins) or released from intracellular stores. The degree to which Cu/Zn concentration increased in the plasma and hemocytes was more dramatic in oysters with high levels of Cu/Zn accumulation. In vitro , Cu and Zn both inhibited the growth of V. harveyi , while Cu plus H 2 O 2 was lethal to the bacteria. The strength of the growth-inhibition and lethal effects depended on the metal dose. In addition to these effects, increases in Cu concentration increased the activity levels of PO in the oyster plasma and hemocytes in vivo and in vitro. However, SOD activity was not affected by Cu or Zn accumulation. Thus, our results suggested that the Cu/Zn burst in the hemolymph was an important factor in the oyster immune reaction, creating a toxic internal environment for the pathogen, as well as catalyzing inorganic or enzymatic reactions to strengthen bacteriostasis. By determining the extent of Cu/Zn burst in the immune response, Cu/Zn accumulated levels could affect the resistance of oysters to pathogens. • Cu and Zn were redistributed in response to V. harveyi infection in C. angulata. • Cu/Zn burst in hemolymph can inhibits bacterial growth. • Cu can catalyze the production of the hydroxyl radical to kill the pathogen. • The increase of Cu can strengthen the activity of PO. • The level of Cu/Zn accumulation affected the size of the Cu/Zn burst during immune response. [ABSTRACT FROM AUTHOR]

of the modern state researches of the Sea of Azov coasts and coastal processes influencing their evolution are presented. A multidisciplinary study of coastal processes allowed us to identify main types of coast evolution: abrasion, accumulation, and stability. Predominance of abrasion is the main feature of modern dynamics of the Azov shores. Not only the parent rock shores are subjected to erosion, but also accumulative forms are eroded. The eastern coast of the sea retreats most rapidly. The intensity of the abrasion and landslide processes is due to the weak resistance of the rocks composing the coast to the wave forcing. In particular, intense abrasion occurs in those parts of the coast where wave forcing is strong together with the surges caused by onshore winds, while the beaches are narrow or completely absent. At the same time, the percentage of beach-forming fractions in eroded soils is low, and the major part of the abrasion material in the form of suspended matter is transported to the deep parts of the sea. In general, the state and dynamics of the Azov coasts are influenced by abrasion-accumulative processes, sea level fluctuations, changes in the wind-wave regime parameters, and fluctuations in the biogenic beach-forming material volumes. The biogenic factor is the most important in the balance of deposits of accumulation forms (spits and bay-bars). Anthropogenic activity also affects the current state of the shores. The transport of beach-forming alluvial sediments into the sea is reduced because of the regulated river discharge. The natural evolution of onshore processes is disrupted during the development of the coast: agricultural activities, industrial and resort construction, removal of sand and shell material, construction of shore protection facilities. [ABSTRACT FROM AUTHOR]

TCS [5-chloro-2-(2,4-dichlorophenoxy)phenol] caused a concentration dependent delay in embryonic development, delay and decline in hatching and reduction in length and weight of hatchlings along with an increase in abnormal/deformed embryos and larvae and percent mortality. These parameters varied in a species specific manner and increased with TCS residue in body. The 96 h LC 50 values of TCS for Cyprinus carpio , Ctenopharyngodon idella, Labeo rohita and Cirrhinus mrigala were estimated at 0.315, 0.116, 0.096 and 0.131 mg/L, respectively. Hatching got delayed by 16.33 h for C. carpio (0.47 and 0.50 mg/L TCS) and C. idella (0.20 mg/L TCS) but by 18.07 h for L. rohita (0.15 mg/L TCS) and by 19.33 h for C. mrigala (0.18 mg/L TCS). Spine malformations, oedema (yolk sac and cardiac) and deflated swim bladder were present in 100% larvae of C. carpio , C. idella , L. rohita and C. mrigala at 0.30, 0.08, 0.13 and 0.14 mg/L TCS, respectively. TCS also caused hemorrhage (all but C. idella, only 3.33%), albinism and deformed caudal fin (C. idella), hypopigmentation and rupturing of yolk sac (C. mrigala), gas bubble disease (C. mrigala and L. rohita), fusion of eyes (C. carpio) and degeneration of digestive tract (L. rohita) in 10–40% hatchlings. Exposed hatchlings were very weak and paralyzed, could not swim and remained settled at the bottom of jars. Embryonic development was observed to be an early indicator of the toxicity of TCS as oedema and bubbles in yolk were observed in 40–100% embryos/hatchlings at 0.08 mg/L TCS while 100% mortality was observed between 0.15 and 0.50 mg/L TCS. L. rohita was most sensitive and C. carpio was least sensitive to the stress of TCS. Accumulation of TCS in the hatchlings (1/10 of TCS in water) after 96 h exposure hints that even small quantities of TCS may change species diversity in natural waters. Image 1 • TCS is highly teratogenic to Cyprinus carpio, Ctenopharyngodon idella, Labeo rohita and Cirrhinus mrigala. • TCS accumulation in hatchlings corresponded with the developmental period/time for hatching time. • 96 h LC 50 value and percentage of abnormal larvae increased with accumulation of TCS in each species. • Embryonic development and growth are better indicators of the stress of TCS compared to mortality. • L. rohita was observed to be the most sensitive and C. carpio to be the least sensitive to the stress of TCS. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a magnetic means of accumulating kinetic energy from a traversing rod (TR) used to guide yarn during winding processes on rotor spinning machines. A passive magnetic system for accumulating kinetic energy at the reversal points of reciprocating motion is introduced, and its unique repulsive magnetic force is described in relation to the specific traversing-motion characteristic. The magnetic damping force phenomenon and preconditions for its application in the machine are also defined and discussed. We also show magnetic field optimisation by means of pole-piece geometry modification to obtain a magnetic force characteristic that closely approximates the required motion characteristic. Thus, the efficiency of kinetic-energy accumulation at the reversal points of the reciprocating motion of the TR is increased. The utilisation of an eddy-current effect on the accumulator body to apply the magnetic-damping phenomenon for vibration reduction is also described. The results of this work demonstrate the promise of the system using modern rare-earth compound-based magnets applicable not only to the studied traversing system but also to various mechanical devices as a non-contact means of reducing deformation and vibration. The developed and experimentally verified mathematical models presented here represent a useful tool for further optimisation of specific applications in the field of mechanics. Graphical abstract Image 1 Highlights • The unique peak-like magnetic repulsive force-distance characteristic of a passive magnetic system. • Passive magnetic system reduces considerably deformation and vibration of the rectilinear-motion based mechanical system. • FEM based models of magnetic systems were experimentally verified with satisfied correspondence. [ABSTRACT FROM AUTHOR]

Abstract Few studies have focused on the influence of environmental conditions on the bioavailability of pollutants interacted with nanomaterials in organisms. In this study, we primarily compared the influence of multiwalled carbon nanotubes (MWCNTs) on the bioavailability of fluoxetine in zebrafish (Danio rerio) larva under different environmental conditions: natural organic matter (NOM) and salinity. The results showed that fluoxetine accumulated in the larvae and then transformed into the metabolite norfluoxetine, with the metabolic rates from 2.8 to 3.5. Following co-exposure to MWCNTs, the accumulation of fluoxetine and norfluoxetine were further enhanced, suggesting a superior carrier of MWCNTs for fluoxetine, especially the functional MWCNTs. The consistent increase in the fluoxetine and norfluoxetine accumulation highlights the bioavailability of absorbed fluoxetine on MWCNTs in zebrafish larvae. The presence of NOM promoted the accumulation of fluoxetine and norfluoxetine in zebrafish, but alleviated the carrier effects of MWCNTs, acting as a natural antidote. Salinity negatively influenced the bioavailability of fluoxetine in the larvae, and further reversed the enhancements caused by MWCNTs. These findings provide a new insight into the influence of environmental conditions on the interactions between nanomaterials and pollutants in organisms. Graphical abstract fx1 Highlights • The accumulation of fluoxetine in larvae transformed into the metabolite norfluoxetine. • MWCNTs facilitated the bioavailability fluoxetine in fish, playing as carriers. • Natural organic matter alleviated the carrier effects of MWCNTs. • Salinity reversed the carrier effects of MWCNTs. [ABSTRACT FROM AUTHOR]

Abstract High concentrations of vanadium, a ubiquitous element in the environment, in growing media leads to deformation of root structure and leaf chlorosis and necrosis, consequently affecting the translocations of nutrients and essential elements. However, the effects of vanadium on essential element uptake, and the interactions of essential elements in the presence of vanadium, remain incompletely understood. To elucidate the effects of different concentrations of vanadium on major and trace essential elements and plant growth, a native plant species growing in a vanadium mining area, Setaria viridis (dog tail's grass), was incubated in solutions containing 0–55.8 mg/L vanadium. The shoot accumulation of four major essential elements and five trace essential elements was detected, and the root length and stem height were measured. The results showed that vanadium in soil solution enhanced the accumulation of all major essential elements in shoot. Vanadium concentrations lower than 47.4 mg/L showed an obvious positive (p < 0.05) effect on P accumulation and translocation. In the case of trace essential elements, there were threshold values for solution vanadium stimulation of element uptake. The threshold values for Cu and Zn, Fe, and Mo uptake were 4.3, 16.3, and 40.6 mg/L, respectively. When vanadium levels surpassed these values, accumulation was suppressed and the solution vanadium concentrations attenuated the solution-to-shoot translocation of most of the essential elements. Among the trace essential elements, translocation of Fe was obviously enhanced (p < 0.05) by vanadium. Solution vanadium also enhanced plant growth at lower concentrations and inhibited it at higher levels. The threshold values for stem height and root length were 36.8 and 16.3 mg/L, respectively. Concentrations of 40 and 55.8 mg/L vanadium in soil solution caused a 50% decrease in root length and stem height, respectively, showing that root length of Setaria viridis is more susceptible to vanadium toxicity than stem growth. Highlights • V in soil solution enhanced the accumulations of major essential elements in shoots. • V in soil solution obviously increased translocations of P and Fe. • The 40 and 55.8 mg/L V caused 50% decrease in root length and stem height. • V lower than 4.3, 16.3, 40.6 mg/L stimulate the accumulations of Cu and Zn, Fe, Mo. [ABSTRACT FROM AUTHOR]

Abstract Rice (Oryza sativa L.) planted in cadmium (Cd)- and arsenic (As)-contaminated soil is considered the main source of dietary Cd and As intake for humans in Southeast Asia and thereby poses a threat to human health. Minimizing the transfer of these pollutants to rice grain is an urgent task for environmental researchers. The main objective of this study was to investigate the effects and the mechanisms of a combined amendment (hydroxyapatite + zeolite + biochar, HZB) on decreasing Cd and As accumulation in rice. In situ remediation and aqueous solution adsorption experiments were conducted. The results showed that after application of HZB, Cd and As concentrations of the exchangeable fraction and TCLP extraction in soil decreased with the growth of rice plants. Cd concentrations in rice tissues were decreased at the tillering, filling and maturing stages after in situ remediation, while As concentrations in rice tissues were decreased only at the maturing stage. When 8 kg·plot−1 (9000 kg ha−1) HZB was applied, concentrations of Cd and inorganic As in brown rice were decreased to 0.18 and 0.16 mg kg−1, respectively, lower than the levels permissible for grain in China, i.e., 0.2 mg kg−1. Application of HZB reduced Cd accumulation in rice tissues, and the suppression of Cd accumulation was significantly greater than that of As. Furthermore, HZB significantly increased rice grain yield. An aqueous solution adsorption experiment demonstrated that HZB could adsorb and covalently bind Cd and As (V) via -OH, -COOH, -Si-O-Si and CO 3 2- groups to produce carboxylates, silicates and carbonates, thereby promoting in situ immobilization of Cd and As in soil solution. Highlights • The soil amendment addition significantly decreased the bioavailabilities of Cd and As in soil. • The soil amendment in situ immobilization of Cd and As in soil by producing carboxylates, silicates and carbonates. • The soil amendment decreased Cd and inorganic As concentrations in brown rice at the same time. • The soil amendment addition significantly increased rice grain yield. [ABSTRACT FROM AUTHOR]

Abstract A pot experiment was conducted to investigate the detoxification mechanism of Agrocybe aegerita (A. aegerita). The physiological responses, subcellular distribution and chemical forms of cadmium (Cd) in A. aegerita grown in Cd stress were analyzed. The results showed that the biomass was decreased under Cd stress, while the production of malonaldehyde, thiols, and low-molecular-weight organic acids (LWMOAs) as well as the antioxidant enzymes in A. aegerita was increased compared with control group. The HPLC results showed that nine LWMOAs were found in A. aegerita with critic acid as the dominant and they played important role in the detoxification and accumulation of Cd in A. aegerita. More Cd was accumulated in pileus than in stipe. Differential centrifugation technique showed that the majority of Cd was compartmentalized in the soluble fraction (53–75%) and bound to the cell wall (19–42%). The proportion of Cd in the cell wall increased with the increase of the accumulation of Cd in the fruiting body, but in the soluble fraction showed an opposite trend. Furthermore, most of the Cd in A. aegerita was mainly in the forms of NaCl- (29–49%) and ethanol-extractable Cd (20–40%). The ethanol- and water-extractable Cd in stipe (60–66%) was higher than in pileus (43–49%). Thus intracellular detoxification mechanisms of Cd in A. aegerita is related to subcellular partitioning and chemical forms of Cd and well-coordinated physiological responses. Highlights • The subcellular distribution and chemical forms of Cd in Agrocybe aegerita were studied in this paper for the first time. • More than 90% of Cd was sequestrated in the soluble fraction and bound to the cell walls. • The proportion of water-soluble Cd in inorganic form and organic form was higher in stipe than in pileus. • Antioxidant enzymes, GSH, T-SH and LWMOAs worked in the accumulation and detoxification of Cd. [ABSTRACT FROM AUTHOR]

Abstract Particulate matter (PM) from cooking is considered one of the most harmful indoor air pollutants causing numerous adverse health effects, and it is essential to comprehend the characteristics of the particles generated from cooking to prevent these problems. In this study, we investigated PM from the pan-frying of salmon using number concentration and developed emission rates as a function of time for ultrafine particles (UFPs < 100 nm) and accumulation mode particles (AMPs 0.1–1 μm). The newly defined emission rates vary significantly with time and are very different from the conventionally determined rates that do not consider the variation of particle concentration with time. The emission rate of UFPs decreased over time after a sharp rise, whereas that of AMPs continued to increase, resulting in a change in the proportions of UFPs and AMPs in the total PM from 93 to 7% to 72 and 28%, respectively. Particle–particle interactions such as coagulation and coalescence were observed between primary particles via high resolution transmission electron microscopy (HR-TEM), which is a plausible reason for the decreasing emission rate of UFPs with time. The emission rate as a function of time can serve as a tool to estimate PM from cooking, as well as to monitor the change trends through phenomena such as agglomeration. Highlights • Development of biomass burning emission rate equation as a function of time for UFPs and AMPs • Fluctuation of UFPs and AMPs proportions in total PM • Observation of particle -particle interaction via TEM analysis [ABSTRACT FROM AUTHOR]

Highlights • We model multiattribute desirability ratings using a preference accumulator. • Our model features decay, inhibition, and stochastic attribute sampling. • We test our model in two experiments. • Our model successfully predicts three new behavioral effects. • Quantitative model fits also provide support for the model. Abstract In desirability rating tasks, decision makers evaluate objects on a continuous response scale. Despite their prominence, full process models of these rating tasks have not been developed. We investigated whether a preference accumulation process, a process often used to model discrete choice, might explain ratings as well. According to our model, attributes from each option are sampled and evaluated stochastically. The evaluations are integrated over time, forming a preference. Preferences for options compete with each other, and accumulated preferences can decay. The model makes precise predictions regarding the statistical distribution of desirability ratings, as well as their dependence on deliberation time and on context. We test and confirm these predictions in two experimental studies. Additionally, quantitative model fits indicate that participants are better described by our proposed model, relative to a model without dynamism, competition, or stochastic attribute sampling. Our results show that the descriptive power of models of preference accumulation extends beyond discrete choice, and that the assumptions of this framework accurately characterize the core cognitive processes at play in the construction of preference and the evaluation of objects. [ABSTRACT FROM AUTHOR]

Abstract Cadmium (Cd) is toxic throughout the food chain. Selenium (Se) can mitigate Cd accumulation in rice plants, although it is unclear why it has such effect. The objectives of this study were to investigate the effects of Se application on Cd-induced oxidative stress and antioxidant activities, and the combined effects of Se application and water management on the formation of iron plaque on the rice surface and Fe, Cd, and Se accumulation in rice plants. Rice seedlings were grown in Cd-contaminated soil with or without the addition of Se, and in aerobic or flooded conditions. Exogenous Se reduced Cd-induced oxidative stress. In the flooded treatment, exogenous selenite significantly decreased Cd concentrations in rice tissues, whereas it noticeably enhanced Cd concentrations in rice tissues in the aerobic treatment. Furthermore, selenite addition and flooding promote the formation of iron plaque and increase Fe concentrations in rice tissues. Pearson correlation analysis shows that plant Cd was significantly negatively correlated with Fe concentrations in rice tissues, and plant Fe was significantly positively correlated with Se concentrations in rice tissues, but no significant correlation was found between Cd and Se concentrations Thus, exogenous selenite may indirectly affect Cd uptake by influencing the formation of iron plaque on rice root surface, Fe uptake and Fe levels in rice. Highlights • Selenite addition significantly alleviated Cd-induced oxidative stress. • Selenite addition and water management significantly affect Cd accumulation in rice tissues. • Selenite may indirectly affect Cd uptake by influencing the formation of iron plaque on rice root surface, Fe uptake and Fe levels in rice. [ABSTRACT FROM AUTHOR]

Abstract While marine animals are exposed to environmental contaminants via their prey, because plastic pollution in the aquatic environment can concentrate some chemicals, ingested plastics are thought to increase the exposure of biota to contaminants. Currently, in the literature there are contradictory results relating to how higher levels of ingested plastics by birds may lead to higher levels of polychlorinated biphenyl (PCBs). To date none of these have incorporated known Toxic Equivalency Factors (TEFs) for non- ortho and mono- ortho congeners of PCB which is critical to assessing the potential effects from PCBs. We examined northern fulmars (Fulmarus glacialis) from the Labrador Sea region Canada, and the ingested plastics from these same birds for comparative PCB concentrations. We found no significant correlations between the PCB concentrations in the birds and the mass or number of retained ingested plastic pieces in the stomach, this held true when PCBs were considered by a number of different ways, including ∑ 4 PCB, ∑PCB, lower-chlorinated, high-chlorinated, non-ortho PCB, and mono- ortho congeners. PCB concentrations were lower in plastics as compared with livers. We found significant differences in congener profiles between the ingested plastics and seabird livers suggesting that while plastics do not contribute to the PCB concentrations, there may be some interactions between plastics and the chemicals that the birds are exposed to via ingested plastics. Highlights • The ingestion of plastics can lead to increased contaminant exposure. • We examined PCB concentrations in seabirds and their ingested plastics. • No significant correlations were found between PCBs and ingest plastics. • There were differences in the PCB concentrations and congener profiles in plastics and livers. • Xenobiotics, such as PCBs, may undergo metabolism in upper trophic level species. [ABSTRACT FROM AUTHOR]

The current study aims to investigate the implications of amending a soil contaminated with Cd with peanut residues biochar (BP) solely or in combination with cow manure (CMPB) at different rates on phytotoxicity of Cd for wheat plants and its distribution in a mine contaminated soil. Soil pH and EC increased progressively in soils amended with either PB or CMPB. Exchangeable Cd was decreased while its non-exchangeable fractions were increased. Dry weights of wheat straw, roots and grains increased when soils amended with either PB or CMPB, especially at the higher application rate. Such increases were correlated significantly with the extractable soil-Cd. Concentrations of Cd in roots were higher than those in straw; whereas, the concentrations in grains seemed to be the lowest. Generally, values of bio-concentration and translocation factors did not exceed “1” and decreased with application of either PB or CMPB. In conclusion, enriching biochar with cow manure is a recommended strategy to reduce Cd uptake and translocation to straw and seeds. Moreover, Concentrations of Cd did not exceed the permissible levels in grains when soils amended with the highest rate of CMPB. [ABSTRACT FROM AUTHOR]

Phytoremediation is regarded as one of the most cost-effective and environmentally friendly strategies for potentially toxical metals (PTMs) contaminated soil remediation. Despite that, continuous studies are conducting to explore the potential plant species in order to achieve enhanced remediation efficiencies. Therefore, in this study, a field investigation was conducted to screen the potential phytoremediation plants from a contaminated site in the surrounding area of a Zn smelter in Feng Country, China. Results indicated that soils in the studied area were severely contaminated with Cd and Zn, while the contents of other metals (Cu, Pb, and Ni) were below the allowanced threshold. Moreover, the contamination was more serious in areas closer to the smelter. The elevated level of contamination had great impacts on plant diversity and abundance. Fifty-nine plant species belonging to 28 families were identified in the studied area, of which plants from the Asteraceae family and herbs were most frequently observed. Plants demonstrated differentiated potential on metal accumulation and translocation, and the total Cd, Cu, Pb, and Zn contents in the aerial parts of plants ranged from 5.57 to 268.5, 14.34 to 140.90, 10.43 to 570.3, and 110.3 to 1350 mg kg −1 , respectively. Symphytum officinale Linn. distinguished itself from the various plants as a promising plant candidate for soil remediation, due to its great capacities for absorbing Cd, Pb, and Zn. Specifically, an individual Symphytum officinale Linn. plant can accumulate up to 5.54, 21.0, and 52.9 mg Cd, Pb, and Zn in its aboveground parts (20.67 g dry weight). Results from this study can provide a reference for the phytoremediation of PTMs contaminated soil in this area or other places with similar soil and climate conditions. [ABSTRACT FROM AUTHOR]

The effects of iron plaque formation on chromium (Cr) uptake and accumulation by rice seedlings ( Oryza sativa L.) were assessed using hydroponic and soil experiments, where each 3 levels of Fe supplementation were added to Hoagland solution (0, 30, and 100 mg Fe 2+ L −1 ) and a typical paddy soil (0, 1, and 2 g Fe 2+ kg −1 ). For each treatment, rice seedlings were exposed to different levels of Cr as chromate at 0, 0.5, 2, 5, 10, and 20 mg L −1 in solution or 300 mg kg −1 in soil. Low levels of Cr supply (0.5, 2, and 5 mg L −1 ) promoted root biomass, while high levels (10 and 20 mg L −1 ) decreased root and shoot biomass and undermined the density and integrity of iron plaque. Iron supply significantly increased the proportion of Cr in iron plaque, but decreased that in rice plants. The results of hydroponic experiment showed that iron plaque formed with Fe supply at 100 mg L −1 markedly reduced Cr accumulation in shoots of rice seedlings when exposure to 10 and 20 mg L −1 Cr. The soil culture experiment also demonstrated that exogenous Fe addition significantly decreased Cr concentration in leaf and stem of rice seedlings. These results suggested that iron plaque with appropriate amount was effective to reduce the uptake and accumulation of Cr in rice plants, which have strong implication for taking measures to regulate Cr accumulation in rice grains. [ABSTRACT FROM AUTHOR]

Olaquindox, is a growth-promoting feed additive for food-producing animals. As the banned medicinal feed additive, olaquindox in animal feed and water must be concerned as an important hazard index. To improve studies of the toxicity of olaquindox, we provide a toxicological effects of olaquindox on a common freshwater fish, Cyprinus carpio L. The results of acute toxicity tests showed that the 7d-LD 50 of olaquindox administered by feeding for common carp was determined to be 3746.3 mg/kg. We also found that the accumulation coefficient of olaquindox in carp was 1.45–1.9. Based on the studied hematological and blood biochemical parameters (RBCs count, hemoglobin content, ALT, AST and SOD activity), we found that olaquindox induced significant alterations in all studied parameters. Regarding bioaccumulation, the results showed that olaquindox had more efficiency to internalize fish tissues (liver, kidneys and muscle). The histopathological investigation of tissues from poisoning fish revealed various alterations that varied between adaptation responses and permanent tissue damage. Our results indicate that olaquindox are toxic to common carp and have obvious accumulation, and all the data from acute and subacute toxicity experiments in common carp may provide a useful tool for assessing the toxicity of olaquindox to aquatic organisms. [ABSTRACT FROM AUTHOR]

Environmental pollution has become a transnational issue that impacts ecosystems, soil, water, and air and is directly related to human health and well-being. Chromium pollution decreases the development of plant and microbial populations. It warrants the need to remediate chromium-contaminated soil. Decontaminating chromium-stressed soils via phytoremediation is a cost-effective and environmentally benign method. Using multifunctional plant growth-promoting rhizobacteria (PGPR) lower chromium levels and facilitates chromium removal. PGPR work by altering root architecture, secreting chemicals that bind metals in the rhizosphere, and reducing phytotoxicity brought on by chromium. The present study aimed to investigate the chromium bioremediation capacity of metal-tolerant PGPR isolate while promoting the growth of chickpeas in the presence of varying levels of chromium (15.13, 30.26, and 60.52 mg/kg of chromium). The isolate, Mesorhizobium strain RC3, substantially reduced chromium content (60.52 mg/kg) in the soil. It enhanced the root length by 10.87%, the shoot length by 12.38%, the number of nodules by 6.64%, and nodule dry weight by 13.77% at 90 days. After 135 days of sowing, more improvement in the root length (18.05), shoot length (21.60%)the chlorophyll content (6.83%), leghaemoglobin content (9.47%), and the highest growth in the crop seed yield (27.45%) and crop protein content (16.83%)The isolate reduced chromium accumulation in roots, shoots, and grains chickpea. Due to chromium bioremediation and its plant growth-promoting and chromium-attenuating qualities, Mesorhizobium strain RC3 could be used as a green bioinoculant for plant growth promotion under chromium stress. [Display omitted] • Mesorhizobium RC3 applied as a bio-inoculant in contaminated soils. • Mesorhizobium RC3 improved chickpea crop performance in metal-contaminated soils. • Mesorhizobium RC3 double the influence on chickpea plants growth in metal treated soil. • Reduced uptake of metals by the plant leading to an increase in the growth. • The mechanism for the toxicity of metals to legumes and the extent of their accumulation in seeds. [ABSTRACT FROM AUTHOR]

Koelreuteria paniculata were cultivated in nutrient solution with different concentrations of Cd (0, 50, 150, 250 and 500 µM) and sampled after 90 days. The resistance, translocation, accumulation and stress responses in Koelreuteria paniculata were investigated by hydroponic experiments. The results showed that Koelreuteria paniculata is an efficient Cd excluder that can tolerate high concentrations of Cd (up to 150–250 µM of Cd). The concentration of Cd never exceeds 5 ppm in leaves and 10 ppm in roots. The high concentration of Cd (≥ 250 µM) had a toxic effect on K. paniculata and significantly restricted the plant growth. The accumulation ability of Cd by different plant tissues followed the sequence of roots > leaves > stems. The bioconcentration factors and translocation factors both were less than 1. Cd has the highest content in the cell wall and is migrated to soluble fractions and organelles at high concentrations. Undissolved Cd phosphate, pectates and protein-bound Cd were the predominant forms. The low concentration of Cd (≤150 µM) promoted the synthesis of soluble proteins, AsA and GSH, while high concentration of Cd clearly inhibited the physiological and biochemical process, caused membrane lipid peroxidation and severe membrane damages, and increased MDA and H 2 O 2 contents. POD, CAT and SOD exhibited positive and effective responses to low concentration Cd stress, but could not remove the toxicity caused by high concentration Cd stress. The content of IAA, GA and ZT decreased and ABA content was significantly increased under high-concentration Cd stress. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a non-essential metal. Its occurrence in the environment is related principally to anthropogenic contamination. Pb is toxic to aquatic organisms and can provoke damage to membranes and inhibit the activity of essential enzymes. The filter-feeding, Manila clam Ruditapes philippinarum is widely used as a biomonitor organism to assess metal toxicity. Among biomarkers related to the Pb toxicity, the enzymatic activity of δ-aminolevulinic acid dehydratase (δ-ALAD) has been adopted as a specific tool. Metallothionein (MT), lipid peroxidation (LPO) and antioxidant enzymes activities, such as catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) and superoxidase dismutase (SOD) have also been employed to assess the toxic effect of metals. Two target tissues, the gills and the digestive gland, were selected to examine biomarker responses. In order to assess the effects of Pb accumulation and the mechanisms involved in the recovery from it, clams were exposed at two Pb levels (10 and 100 µg/L) for 7 days and were later maintained in clean water for 7 days as a depuration period. Pb accumulation was dependent on the exposure concentration and higher Pb levels were observed in the gills compared to the digestive gland. Inhibition of δ-ALAD, GST and SOD and the induction of MT and LPO over the exposure period were observed in the gills and the digestive gland of R. philippinarum . The depuration period showed a continuous inhibition of the δ-ALAD activity and induction of MT and LPO in both tissues. These results demonstrate that lead induced an exposure effect and the 7 days of depuration were not sufficient to recover the basal health status of the clams. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a highly biotoxic heavy metal that contaminates the environment. Phytoremediation is a green technology for environmental remediation and is used to clean up Hg contaminated soil in recent years. In this study, we isolated an ATP-binding cassette (ABC) transporter gene PtABCC1 from Populus trichocarpa and overexpressed it in Arabidopsis and poplar. The transgenic plants conferred higher Hg tolerance than wild type (WT) plants, and overexpression of PtABCC1 could lead to 26–72% or 7–160% increase of Hg accumulation in Arabidopsis or poplar plants, respectively. These results demonstrated that PtABCC1 plays a crucial role in enhancing tolerance and accumulation to Hg in plants, which provides a promising way for phytoremediation of Hg contamination. [ABSTRACT FROM AUTHOR]

The present study was intended to investigate the role of amino acid glycine in detoxification of As in Oryza sativa L. The growth parameters such as, shoot length and fresh weight were decreased during As(III) and As(V) toxicity. However, the application of glycine recovered the growth parameters against As stress. The application of glycine reduced the As accumulation in all the treatments, and it was more effective against As(III) treatment and reduced the accumulation by 68% in root and 71% in shoot. Similarly, the translocation of As from root to shoot, was higher against As(III) and As(V) treatments, whereas, reduced upon glycine application. The translocation of Fe and Na was also affected by As, which was lower under As(III) and As(V) treatments. However, the application of glycine significantly enhanced the translocation of Fe and Na in the shoot. Besides, the expression of lower silicon transporters i.e. Lsi-1 and Lsi-2 was observed to be significantly suppressed in the root with the application of glycine against As treatment. Similarly, the expression of three GRX and two GST gene isoforms were found to be significantly increased with glycine application. Simultaneously, the activities of antioxidant enzymes i.e. l -arginine dependent NOS, SOD, NTR and GRX were found to be significantly enhanced in the presence of glycine. Increased activities of antioxidant enzymes coincided with the decreased level of TBARS and H 2 O 2 in rice seedlings. Overall, the results suggested that the application of glycine reduces As accumulation through suppressing the gene expression of lower silicon transporters and ameliorates As toxicity by enhancing antioxidants defense mechanism in rice seedlings. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and lead (Pb) pollutions caused by industrial activities are one of the most serious threats to aquatic ecosystems. The aim of this study is to investigate the Cd and Pb bioaccumulations and diverse physiological and biochemical properties of Ceratophyllum demersum L. exposed to different concentrations of Cd (0.5–2.0 mg/L) and Pb (25–100 mg/L) in aqueous media for 1, 3 and 5 days. Cd and Pb accumulations increased with increase in the exposure times and concentrations, and the highest accumulation values of Cd and Pb were recorded at 2 mg/L (2668.33 mg/kg dw) and 100 mg/L (22,504.10 mg/kg dw), respectively, after 5 days. However, higher bioconcentration factors (BCF) were calculated as 645.43 at 25 mg/L Pb and as 1357.92 at 1 mg/L Cd after 5 days. The results showed that photosynthetic pigments (chlorophyll a , b and carotenoids) and protein contents of the plants exposed to Cd and Pb toxicities decreased with increasing metal concentration and exposure time, whereas their malondialdehyde (MDA) contents increased. Additionally, the single and synergistic effects of duration and metal concentration on the fresh and dry weights of the plant were determined. The results of this study reveal that C. demersum , propagated by tissue culture technique, can be used effectively in the phytoremediation of aquatic environments contaminated by Cd and Pb. This study will also make a positive contribution to the progression of new phytotechnologies on the purpose of the remediation of wastewater by plants in future. [ABSTRACT FROM AUTHOR]

New England estuaries provide essential feeding grounds and nursery habitat for important recreational and commercial species. However, these functions are being altered by a recent shift in estuarine plant dominance from rooted plants to opportunistic drift macroalgae that can form dense accumulations. We hypothesize that formation of these macroalgal accumulations is controlled by the level of nutrient enrichment and the low hydrodynamic energy regime present in many estuarine basins. To test this hypothesis, we conducted temporal macroalgae surveys in eight s.e. Massachusetts estuaries to quantify the level of accumulation within basins with varying levels of nitrogen enrichment and bottom currents. Our results indicate that opportunistic Ulva spp. dominated the macroalgal community in both estuaries with temporal surveys, Green and Great Ponds. Measurements of tidal transport revealed a net import of macrophyte material but with no import or export of Ulva . Within each estuary, occurrence of opportunistic macroalgae was positively related to levels of water column total nitrogen (R 2 = 0.76) and growth rate of Ulva spp. directly related to total nitrogen + light level (R 2 = 0.92), while bottom coverage was >20% at TN levels >0.48 mgL −1 . We conclude that opportunistic species accumulate in response to nutrient enrichment with in situ processes controlling growth and decay, while import and tidal transport play relatively minor roles in the distribution of opportunistic drift macroalgae in these shallow estuaries. [ABSTRACT FROM AUTHOR]

Salvinia minima was assessed for its ability to accumulate lead (Pb) by exposing it to concentrations of 40 µM Pb(NO 3 ) 2 during 24 h. At the same time, the expression levels were quantified, of four genes coding for transporters: SmABCC (ABCC-MRP), SmATPase (ATPase-P3A), SmNhaD (Type-Na + /H + ) and SmABCG (ABCG-WBC). In the absence of lead, S. minima had very low expression of those genes, when plants were exposed to the metal however, those genes showed a rapid (in just three hours or less) and sharp increase (up to 60 times) in their expression, particularly the SmNhaD (Type-Na + /H + ) gene. This sharp increase in expression levels of the genes studied, occurred at the same time that the plant accumulated the highest content of lead in its tissues. The first two genes, are apparently implicated in detoxification and lead accumulation mechanisms, while the other two genes are apparently involved in maintaining cell balance (homeostatic control) and membrane integrity. Our results confirmed that S. minima is efficient for phytoremediation of water bodies contaminated by lead, as it is efficient in accumulating this metal in its tissues (bioconcentration factor; BCF) values greater than 1000, in short times of exposure. More importantly, our data on the expression profiles of four genes coding for transporters, represent a first sight scenario of the molecular basis for understanding the different mechanism of detoxification, apparently present in this aquatic fern. [ABSTRACT FROM AUTHOR]

In the present study, the possible associations between selected persistent organic pollutants (POPs) and biological factors were assessed in different tissues of two Antarctic notothenioid fish: Notothenia rossii (NOR) and Trematomus newnesi (TRN) collected at Potter Cove, King George Island/Isla 25 de Mayo, South Shetland Islands. Specifically, association patterns between biological factors (body size, lipid content, body condition) and POP concentrations (polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and metabolites, polybrominated diphenyl ethers (PBDEs), and hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), chlordanes (CHLs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs)), were explored by using two approaches: multivariate analyses (principal component analysis: PCA) and intraspecific correlations. Integrating results suggest that biological factors such as size, KI and tissue type seemed to be associated to selective accumulation of POPs for immature specimens of N. rossii , and KI and tissue type for mature specimens of T. newnesi . Each particular factor should be considered when choosing N. rossii or T. newnesi as sentinels for POPs pollution in Antarctic marine environments. Further, both nototheniids showed a selective accumulation pattern in their gonads of penta-chlorinated biphenyls ( penta- CBs; 55.5 and 29 ng g −1 lw for N. rossii and T. newnesi , respectively) and organochlorine pesticides such as DDTs (199 and 13.3 ng g −1 lw, for N. rossii and T. newnesi respectively), and of polybrominated diphenyl ethers (PBDEs) in gills (97.2 and 22.1 for ng g −1 lw, for N. rossii and T. newnesi , respectively), highlighting the importance of these tissues in monitoring studies of pollution in fish. The current study expands the knowledge concerning the biological factors to be investigated when specific pollutants are monitored and supports the importance of tissue type for the selective accumulation of POPs in Antarctic fish. Additionally, a contribution to the scarce data on concentration of MeO-PBDEs in Antarctic marine organisms, particularly in the highly diverse perciform suborder Notothenioidei is provided. [ABSTRACT FROM AUTHOR]

Organic acids play an important role in cadmium availability, uptake, translocation, and detoxification. A sand culture experiment was designed to investigate the effects of citric acid on Cd uptake, translocation, and accumulation in tall fescue and Kentucky bluegrass. The results showed that two grass species presented different Cd chemical forms, organic acid components and amount in roots. The dormant Cd accumulated in roots of tall fescue was the pectate- and protein- integrated form, which contributed by 84.85%. However, in Kentucky bluegrass, the pectate- and protein- integrated Cd was only contributed by 35.78%, and the higher proportion of Cd form was the water soluble Cd-organic acid complexes. In tall fescue, citric acid dramatically enhanced 2.8 fold of Cd uptake, 3 fold of root Cd accumulation, and 2.3 fold of shoot Cd accumulation. In Kentucky bluegrass, citric acid promoted Cd accumulation in roots, but significantly decreased Cd accumulation in shoots. These results suggested that the enhancements of citric acid on Cd uptake, translocation, and accumulation in tall fescue was associated with its promotion of organic acids and the water soluble Cd-organic acid complexes in roots. [ABSTRACT FROM AUTHOR]

Soil and water contamination from heavy metals and metalloids is one of the most discussed and burning global issues due to its potential to cause the scarcity of healthy food and safe water. The scientific community is proposing a range of lab and field based physical, chemical and biological solutions to remedy metals and metalloids contaminated soils and water. The present study finds out a possibility of Chromium (Cr) extraction by sunflower from spiked soil under chelating role of citric acid (CA). The sunflower plants were grown under different concentrations of Cr (0, 5, 10 & 20 mg kg −1 ) and CA (0, 2.5 & 5 mM). Growth, biomass, gas exchange, photosynthesis, electrolyte leakage (EL), reactive oxygen species (ROS; malondialdehyde (MDA), hydrogen peroxide (H 2 O 2 ) and the activities of antioxidant enzymes such as, superoxide dismutase (SOD), guaiacole values peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT) were measured. The results depicted a clear decline in plant height, root length, leaf area, number of leaves and flowers per plant along with fresh and dry biomass of all parts of plant with increasing concentration of Cr in soil. Similar reduction was observed in chlorophyll a and b, total chlorophyll, carotenoids, soluble protein, gas exchange attributes and SPAD. The increasing concentration of Cr also enhanced the Cr uptake and accumulation in plant roots, stem and leaves along with the production of ROS and EL. The activities of antioxidant enzymes increased with increasing Cr concentration from 0 to 10 mg, but decreased at 20 mg kg −1 soil. The CA application significantly alleviated Cr-induced inhibition of plant growth, biomass, photosynthesis, gas exchange, soluble proteins and SPAD value. Presence of CA also enhanced the activities of all antioxidant enzymes and reduced the production of ROS and EL. The chelating potential of CA increased the concentration and accumulation of Cr in plant roots, stem and leaves. It is concluded that the sunflower can be a potential candidate for the remediation of Cr under CA treatment, while the possibility may vary with genotype, Cr level and CA concentration. [ABSTRACT FROM AUTHOR]

Long-term use of fluoride contaminated groundwater to irrigate crops; especially paddy rice ( Oryza sativa L.) has resulted in elevated soil fluoride levels in Eastern India. There is, therefore, growing concern regarding accumulation of fluoride in rice grown on these soils. A laboratory experiment was conducted to investigate the effect of F on germination and phytotoxicity of four varieties of rice ( Orzya sativa L.) (MTU-1010; IET-4094; IET-4786 and GB-1) grown in petri dish in a green house with inorganic sodium fluoride (NaF). Three different levels (0, 5, 10 and 20 mg/L) of NaF solution were applied. At the end of the experiment (28 days), biochemical analysis (pigment, sugar, protein, amino acid and phenol), lipid peroxidation, root ion leakage and catalase activity along with fluoride accumulation and fresh and dry weight of roots and shoots of four cultivars were measured. The results revealed that all the four studied varieties exhibited gradual decrease of germination pattern with increasing concentration of F. Pigment and growth morphological study clearly demonstrated that the variety IET-4094 was the least influenced by F compare to the other three varieties of rice. The translocation factor (TF) was recorded to be the highest for variety IET-4786 (0.215 ± 0.03) at 5 mg/L F concentration. All the four varieties showed higher level of fluoride accumulation in root than in shoot. Variable results were recorded for biochemical parameters and lipid peroxidation. Catalase activity and relative conductivity (root ion leakage) gradually increased with increasing F concentration for all the four varieties. It is speculated that fluoride accumulation in rice straw at very high levels will affect the feeding cattle and such contaminated straw could be a direct threat to their health and also, indirectly, to human health via presumably contaminated meat and milk. [ABSTRACT FROM AUTHOR]

The expression of hemoglobin (Hb) genes has considerable potential as a biomarker for environmental monitoring in Chironomus . However, no sequence information is available regarding Hb genes in Propsilocerus akamusi (Tokunaga), thus the change in Hb mRNA gene expression caused by environmental pollutants remains unknown. In this study, we cloned two Hb gene fragments (PaHbV and PaHbVII) from P. akamusi , analyzed the expression patterns of the PaHbV and PaHbVII transcripts in different tissues using Real-Time quantitative PCR (RT-qPCR), and also measured the Cd levels in different tissues exposed to a sublethal concentration. The results showed significantly increased Cd concentrations and tissue-specific Cd distribution patterns in all of the tissues tested, including the hemolymph, during all time courses. A model describing the roles of specific tissues in Cd uptake and accumulation dynamics was also determined. The Malpighian tubules, gut, and epidermis were the primary sites of Cd accumulation, whereas the hemolymph was the temporary target organ of Cd accumulation, with the Cd being transferred to other internal tissues via the hemolymph. The relative mRNA expression profiles of PaHbV and PaHbVII indicated that their expression levels differed across the different tissues, indicating a tissue-specific response. Our results suggested a reverse effect between Hb expression and Cd accumulation during long-term Cd exposure in comparison with previous studies. The expressions of Hb genes in P. akamusi could be developed as biomarkers for assessing the general health conditions of freshwater ecosystems. [ABSTRACT FROM AUTHOR]

By studying the dynamic characteristics of and key growth stages for mercury (Hg) enrichment in rice, the Hg migration and translocation processes in this species can be better understood. In this study, a pot experiment was conducted, wherein two rice cultivars, Tianyouhuazhan (TYHZ, indica) and Zhendao 18 (ZD18, japonica), were selected and planted for analysing the Hg accumulation kinetic characteristics in rice plants. The plants were sampled at each growth stage, and the biomass and total Hg (THg) and methylmercury (MeHg) concentrations of each tissue were measured. The relative Hg contribution rates (CRs) in whole rice plants and rice grains were calculated, and the growth stage with the highest relative contribution was identified as the key growth stage for Hg accumulation. The results indicated that in rice, the MeHg translocation capability was stronger than the THg translocation capability. Significant differences in the kinetic characteristics of Hg accumulation were found between the two rice cultivars, and the TYHZ rice grains had a stronger Hg accumulation ability than the ZD18 rice grains. The key growth stages for THg accumulation in whole rice plants of both cultivars were the tillering and booting stages, while that for MeHg accumulation was the tillering stage. The key period for Hg accumulation in rice grains was the grain filling stage for both cultivars. The insights from this study could provide scientific guidance for the safe production of rice in Hg-contaminated soil. • Tillering and booting stages were the key stages for THg accumulation in rice plant. • Tillering stage was the key stage for MeHg accumulation in rice plant. • Grain filling stage was the key stage for THg and MeHg accumulation in rice grain. [ABSTRACT FROM AUTHOR]

The golden rule of material accumulation can be defined as the ability of society to process materials as the benefit of capital, with physical investments as the expense of the process. Societies are incentivized to accumulate resources while disregarding resource restrictions. Since they earn more on such a path, despite how unsustainable it is. We propose the material dynamic efficiency transition as a policy tool for sustainability, with the goal of slowing down material accumulation as an alternative sustainable path. The material dynamic efficiency transition is characterized by a simultaneous drop in savings and depreciation rates. In this paper, we first examine a sample of 15 countries -using dynamic efficiency measures-in terms of their economies' responses to declining depreciation and saving tendencies. We then construct a large sample of material stock estimation and economic characteristics for 120 countries to examine the socioeconomic and long-term developmental implications of such a policy. We found that investment in the productive sector withstood the scarcity of available savings, whereas residential building and civil engineering investments reacted intensely to the changes. We also reported on the continuous rise in developed countries' material stock, accentuating the civil engineering infrastructure as a focal point of the related policies. The material dynamic efficiency transition shows a substantial reduction effect of 7.7%–10%, depending on the stock type and development stage. Therefore, it can be a potent tool for slowing material accumulation and mitigating the environmental implications of this process without causing significant disruptions in economic processes. • Economic transition proposed in this study limits material stock endowment by 7%. • The transition does not harm economic performance at macro-scale. • High-income countries resist the policy; thus, measures on land use are demanded. [ABSTRACT FROM AUTHOR]

Growing evidence indicates that astrocytes are tightly connected to Alzheimer's disease (AD) pathogenesis. However, the way in which astrocytes participate in AD initiation and progression remains to be clarified. Our previous data show that astrocytes engulf large amounts of aggregated amyloid-beta (Aβ) but are unable to successfully degrade the material. In this study, we aimed to evaluate how intracellular Aβ-accumulation affects the astrocytes over time. For this purpose, human induced pluripotent cell (hiPSC)-derived astrocytes were exposed to sonicated Aβ-fibrils and then cultured further for one week or ten weeks in Aβ-free medium. Cells from both time points were analyzed for lysosomal proteins and astrocyte reactivity markers and the media were screened for inflammatory cytokines. In addition, the overall health of cytoplasmic organelles was investigated by immunocytochemistry and electron microscopy. Our data demonstrate that long-term astrocytes retained frequent Aβ-inclusions that were enclosed within LAMP1-positive organelles and sustained markers associated with reactivity. Furthermore, Aβ-accumulation resulted in endoplasmic reticulum and mitochondrial swelling, increased secretion of the cytokine CCL2/MCP-1 and formation of pathological lipid structures. Taken together, our results provide valuable information of how intracellular Aβ-deposits affect astrocytes, and thereby contribute to the understanding of the role of astrocytes in AD progression. • Human iPSC-derived astrocytes engulf large amounts of aggregated Aβ, but do not effectively degrade the ingested material. • The Aβ is stored within LAMP1 positive organelles for at least 10 weeks in culture. • The Aβ-containing astrocytes show sustained reactivity markers and an altered cytokine profile. • The Aβ accumulation induces endoplasmic reticulum swelling and formation of pathological lipid structures. [ABSTRACT FROM AUTHOR]

Chromium (Cr) is reported to be hazardous to environmental components and surrounding biota when levels exceed allowable thresholds. As Cr is extensively utilized in different industries, thereby comprehensively studied for its toxicity. Along with Cr, the applications of nano-Cr or chromium oxide nanoparticles (Cr 2 O 3 -NPs) are also expanding; however, the literature is scarce or limited on their phytotoxicity. Thereby, the current work investigated the morpho-physiological insights of macro- and nanoparticles of Cr in Hordeum vulgare L. plants. The increased accumulation and translocation of Cr under the exposure of both forms disturbed the cellular metabolism that might have inhibited germination and growth as well as interfered with the photosynthesis of plants. The overall extent of toxicity was noticeably higher under nanoparticles' exposure than macroparticles of Cr. The potential cue for such phytotoxic consequences mediated by Cr nanoparticles could be an increased bioavailability of Cr ions which was also supported by their total content, mobility, and factor toxicity index. Besides, to support further these findings, synchrotron X-ray technique was used to reliably identify Cr-containing compounds in the plant tissues. The X-ray spectra of the near spectral region and the far region of the spectrum of K-edge of Cr were obtained, and it was established that the dominant crystalline phase corresponds to Cr 2 O 3 (eskolaite) from the recorded observations. Thus, the obtained results would allow revealing the mechanism of macro- and nanoparticles of Cr induced impacts on plant at the tissue, cellular- and sub-cellular levels. [Display omitted] • The speciation of macro- and nano-dispersed Cr along with morpho-physiological responses were studied in Hordeum vulgare L. • The mobility of nano-dispersed Cr in soil was considerably high as compared to macro-dispersed Cr. • The accumulated nano-Cr in plants was in the form Cr 2 O 3 , whilst this fraction was 95% in the case of macro-dispersed Cr. • The extent of soil toxicity was maximal in case of nano-dispersed Cr treatment. [ABSTRACT FROM AUTHOR]

The presence of heavy metals (HMs) in aquatic ecosystems is a universal concern due to their tendency to accumulate in aquatic organisms. HMs accumulation has been found to cause toxic effects in aquatic organisms. The common HMs-induced toxicities are growth inhibition, reduced survival, oxidative stress, tissue damage, respiratory problems, and gut microbial dysbiosis. The application of dietary probiotics has been evolving as a potential approach to bind and remove HMs from the gut, which is called "Gut remediation". The toxic effects of HMs in fish, mice, and humans with the potential of probiotics in removing HMs have been discussed previously. However, the toxic effects of HMs and protective strategies of probiotics on the organisms of each trophic level have not been comprehensively reviewed yet. Thus, this review summarizes the toxic effects caused by HMs in the organisms (at each trophic level) of the aquatic food chain, with a special reference to gut microbiota. The potential of bacterial probiotics in toxicity alleviation and their protective strategies to prevent toxicities caused by HMs in them are also explained. The dietary probiotics are capable of removing HMs (50–90%) primarily from the gut of the organisms. Specifically, probiotics have been reported to reduce the absorption of HMs in the intestinal tract via the enhancement of intestinal HM sequestration, detoxification of HMs, changing the expression of metal transporter proteins, and maintaining the gut barrier function. The probiotic is recommended as a novel strategy to minimize aquaculture HMs toxicity and safe human health. [Display omitted] • HMs accumulation causes toxic effects in the aquatic organism. • Probiotics widely play a potential role to remove HMs from the gut. • Dietary probiotics are capable of removing HMs (50-90%) primarily from the gut. [ABSTRACT FROM AUTHOR]

The toxicokinetics of zinc in the earthworm Eisenia andrei was investigated following exposure for 21 days to ionic zinc (ZnCl 2 ) or zinc oxide nanoparticles (ZnO-NPs) in Lufa 2.2 soil, followed by 21 days elimination in clean soil. Two concentrations were tested for both ZnCl 2 (250 and 500 μg Zn g −1 ) and ZnO-NPs (500 and 1000 μg Zn g −1 ), corresponding to EC 25 and EC 50 for effects on reproduction. Based on the measured internal Zn concentrations in the earthworms over time of exposure, the kinetics parameters k a – assimilation rate constant (g soil g −1 body weight day −1 ) and k e – elimination rate constant (day −1 ) were estimated using a one-compartment model for either total Zn concentrations in the soil or porewater Zn concentrations. In the ZnCl 2 treatments, k a was higher for total Zn concentrations in soil, whereas in the ZnO-NP treatments, k a was higher for porewater Zn concentrations. The value of k e did not differ between the two Zn forms (ZnCl 2 vs ZnO-NPs) for either EC 50 or EC 25 when related to total Zn concentrations in soil, but for EC 50 , k e related to porewater Zn concentrations was significantly higher for ZnCl 2 than for ZnO-NPs. It is concluded that differences in kinetic parameters between treatments were connected with exposure concentrations rather than with the form of Zn. Zinc was efficiently regulated by the earthworms in all treatments: a 2-fold increase in exposure concentration resulted in a less than 2-fold increase in internal concentration, and after transfer to uncontaminated soil the internal Zn concentrations in the earthworms returned to ca 111 μg g −1 dw in all treatments. [ABSTRACT FROM AUTHOR]

A pot experiment was carried out to investigate the single and combined effect of different concentrations of sulfadiazine (SDZ) (1 and 10 mg kg −1 ) and copper (Cu) (20 and 200 mg kg −1 ) stresses on growth, hydrogen peroxide (H 2 O 2 ), malondialdehyde (MDA), antioxidant enzyme activities of wheat seedlings and their accumulation. High SDZ or Cu level significantly inhibited the growth of wheat seedlings, but the emergence rate was only inhibited by high SDZ level. The presence of Cu reduced the accumulation of SDZ, whereas the effect of SDZ on the accumulation of Cu depended on their concentrations. Low Cu level significantly increased the chlorophyll content, while high Cu level or both SDZ concentrations resulted in a significant decrease in the chlorophyll content as compared to the control. Additionally, H 2 O 2 and MDA contents increased with the elevated SDZ or Cu level. The activities of superoxide dismutase, peroxidase and catalase were also stimulated by SDZ or Cu except for the aerial part treated by low Cu level and root treated by high SDZ level. The joint toxicity data showed that the toxicity of SDZ to wheat seedlings was generally alleviated by the presence of Cu, whereas the combined toxicity of SDZ and Cu was larger than equivalent Cu alone. [ABSTRACT FROM AUTHOR]

Ametryn is a selective herbicide belonging to the triazine family and widely used for killing annual grasses or weeds in China and other parts of the world. However, reports on its environmental risk assessment with regard to soil and crop contamination are limited. In this study, accumulation of ametryn in wheat, maize, ryegrass and alfalfa crops along with ametryn residues in the soil planted with the plants were comparatively investigated. Soil enzyme activities and low molecular weight organic acids (LMWOAs), as well as antioxidant and degradation enzyme activities in plant tissues were measured. The maximum accumulation of ametryn was found in shoots and roots of wheat and alfalfa. Ryegrass had the maximum ametryn translocation factor (TF) from roots to shoots, with more than three times over the other crops. The ametryn residue in ryegrass-planted soil was much lower than that in soil planted with others. The residual content of ametryn in crop-planted soils was ordered as rhizosphere soil