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The presence of cadmium (Cd) in food produced in Latin America has been highlighted in recent years. Cadmium can be toxic to humans at low levels, and therefore monitoring its presence in food is relevant for public health. Cadmium concentrations from different sources, such as water, soil, sediment, food, and beverages were examined and discussed to address the non-occupational exposure of the Latin American population to Cd. A literature review was conducted examining publications from 2015 to 2020 and data available in the ScienceDirect and PubMed databases. Twenty-eight papers reported on Cd in water, 49 reported Cd in soil and sediments, and 86 reported on Cd in food. We have identified and discussed the factors affecting the environmental behavior and bioaccumulation of Cd, the main species used in monitoring studies, and the necessity for future research. Brazil and Mexico are the countries that provided the most available information, whereas for some countries in Central America, no information was found. The Cd levels in food examined in these studies (mostly fish and cacao) were generally below the established maximum levels, indicating a low risk. When considering the presence of Cd in food, water, and soil, Cd fractionation and chemical speciation studies are fundamental to understanding which forms of Cd are the most toxic. In turn, studies on bioaccessibility and bioavailability of Cd in food are also needed for more adequate risk assessment, but they are currently scarce within Latin America.

Cadmium (Cd), a highly toxic heavy metal for crops in China, poses a significant threat to rice cultivation. It is crucial to identify the genotypes with robust resistance to heavy metals, including Cd, in rice. The experiment was conducted to examine the mitigation effect of silicon (Si) on Cd toxicity levels in Se-enriched Z3055B and non-Se-enriched G46B rice genotypes. A basal dose of Si improved the growth and the quality of rice significantly by reducing the Cd content in rice roots, stems, leaves and grains and increased the yield, biomass and selenium (Se) content of brown rice in both genotypes. Additionally, Se content in brown rice and polished rice was notably higher in Se-enriched rice than in non-Se-enriched rice, with the highest amount at 0.129 mg/kg and 0.085 mg/kg, respectively. The results demonstrated that a basal fertilizer concentration of 30 mg/kg of Si was more effective in reducing Cd transport from roots to shoots in Se-enriched rice than in non-Se-enriched rice genotypes. Therefore, it can be concluded that Se-enriched rice genotypes are a viable option for food crop production in Cd-contaminated areas.

In this article we discuss cadmium pollution in the environment and the various ways plants take up cadmium and respond to its accumulation. The increased development of metallurgical and mining industries is primarily responsible for the increases in cadmium pollution in the environment. Another significant source of cadmium contamination of agricultural plants is the widespread use of phosphorus fertilizers, which contain cadmium. Cadmium reduces the growth and development of plants. Cadmium in the soil also competes with the basic essential mineral elements thereby reducing their uptake by plants. This article reviews the published data on the cellular and molecular mechanisms of cadmium uptake by plants, its metabolic transformations, effects on nutrient status of plants, modulation of cadmium response by polyamines and amino acids, and the growth of plants. Strategies to reduce cadmium uptake and accumulation are also discussed.

In view of the problems of long remediation time, high energy consumption and low remediation efficiency in electrokinetic remediation of heavy metal contaminated soil, Cd was used to simulate heavy metals in contaminated soil, and response surface method (RSM) was used to optimize the factors influencing electrokinetic remediation. Central Composite (CCD) experimental design method was taken to study the effects of electric field strength, remediation time and water content on removal rate of Cd in soil. Also, polynomial regression mathematical model and optimal reaction conditions were provided for Cd pollution in electrokinetic soil remediation. The simulated equation F was 15.67, the correlation coefficient was 0.9338, and the adjustment correlation coefficient was 0.9042, indicating good regression and strong significance of the equation. The model results showed that, for the optimal experimental conditions, electric field strength was 2.25V·cm-1, the remediation time was 120.79h, and the water content was 17.06%. On the basis of such reaction condition, intermittent current flow method was adopted d to further enhance the electrokinetic remediation effect. The cadmium removal rate in the soil was increased by 3.17%, 2.86% and 2.43%, respectively, and the electric energy consumption was decreased by 10.54%, 11.28% and 9.97%, respectively, suggesting that the method could effectively improve the removal rate of Cd and reduce energy consumption.

Sediment pollution caused by potentially harmful trace elements (PHTEs) has attracted a great deal of attention, due to the persistent risks it poses to human beings and ecosystems. However, the pollution status and source identification of PHTEs from the middle and lower reaches of Huaihe River remains unclear. In this study, arsenic, cadmium, chromium, copper, nickel, zinc, lead and isotopic ratios in the lacustrine sediments of this river are investigated to determine the source of, and ecological risk posed by, these PHTEs. The results show that the concentrations of chromium, copper, nickel and zinc are generally close to the background values in the lacustrine sediments, and are assessed as representing a low degree of contamination. By contrast, significantly higher concentrations of arsenic and cadmium are commonly measured in the upper sediments, which are mainly derived from the agricultural application of fertilizers, pesticides and wastewater. Meanwhile, possible atmospheric lead deposition is identified by the isotopic analysis. Among these PHTEs, adverse biological effects of arsenic, chromium, and nickel may occur in lakes according to consensus-based sediment quality guidelines, but cadmium is selected as a PHTE for priority control according to potential ecological risk index. Our study highlights that developing regional sediment quality guidelines and soil restoration in the catchment are crucial for the freshwater ecosystem in the middle and lower reaches of Huaihe River.

The aim of this paper was cadmium removal from waste water using SiO2 nanoparticles and fungal biomasses. Five treatments were used for cadmium removal. They were inactivated mycelia of Cladosporium sphaerospermum (CLA) and Fusarium oxysporum (FUS), SiO2 nanoparticles (N-Si) and their combinations (N-Si-CLA and N-Si-FUS). The biosorbents natures and combinations were examined by Fourier Transform Infrared (FT-IR) and Scanning Electron Microscope (SEM) where close attachments between combined biosorbents were detected. Different factors affecting cadmium biosorption capacity were tested. It was found that (N-Si-CLA) and (N-Si-FUS) were the most potent biosorbents at pH 7. Thirty minutes contact time exerted maximum sorption capacity. Initial cadmium concentration was optimum at 0.5 mol-1 for highest biosorption capacity. Ca2+ displayed synergistic interfering more than Na+ and K+, respectively. Two real waste water samples collected from two factories were tested to depollute cadmium using the five sorbents. (N-Si-CLA) and (N-Si-FUS) were the most potent adsorbents, where 65.73 % and 54.30% removed in the first sample and 61.33 % and 56.50 % in the second one, respectively. From the results, it was concluded that bioremediation of cadmium from waste water was possible by using SiO2 nanoparticles and fungal biomasses with high efficiency of their combinations.

Cadmium pollution in soil is a long-term and urgent problem, which directly affects the edible value of sunflower and winter wheat and may cause harm to human health. Breeding new varieties with low cadmium accumulation can effectively reduce the content of this element in seeds and fundamentally solve the risk of cadmium entering the human body through seeds and oil. In this paper, the method and significance of breeding sunflower and winter wheat with low cadmium accumulation were discussed.

This paper focuses on the status quo of heavy metal cadmium pollution sites, analyzes and summarizes the physical, chemical and bioremediation technologies of cadmium contaminated soil, and carefully analyzes the advantages and disadvantages of each repair technology. It pointed out the need to develop scientific, efficient and comprehensive restoration management techniques.

Water scarcity and the uneven distribution of water resources in China have resulted in water shortages for agricultural irrigation in arid and semi-arid areas. Reclaimed water used for agricultural irrigation has become an effective solution in the context of the global water shortage. In order to improve soil productivity and solve the shortage of water resources, we carried out reclaimed water irrigation experiments on polluted soil. Compared with full irrigation treatments, the EC value of reclaimed water under deficit irrigation treatments decreased by 2.89–42.90%, and the content of organic matter increased by 6.31–12.10%. The proportion of Acidobacteria community in soils with different cadmium concentration gradients irrigated with reclaimed water ranged from 13.6% to 30.5%, its relative abundance decreased with the increase of soil cadmium concentration. In particular, the relative abundance of Pseudomonas pathogens in deficit irrigation treatments was lower than that of the full irrigation treatments. RDA analysis showed that the environmental factors that played a leading role in the change of microbial community structure were organic matter and pH. Furthermore, the metabolic function potential of the rhizosphere soil bacterial community in deficit irrigation treatments was higher than that of full irrigation treatments with reclaimed water. This study proved that reclaimed water irrigation for cadmium contaminated soil did not aggravate the pollution level and promoted the soil ecological environment with better microbial community diversity.

Cadmium pollution turns out to be a global environmental problem. This study conducted a quantitative and qualitative bibliometric analysis based on 9188 research items from the Web of Science Core Collection published in the last 20 years (2000-2020), presenting an in-depth statistical investigation of global freshwater cadmium research progress and developing trend. Our results demonstrated that the researchers from China, the USA, and India contribute the most to this field. The primary sources of cadmium are mining, industry, wastewater, sedimentation, and agricultural activities. In developing countries, cadmium exposure occurs mainly through the air, freshwater, and food. Fish and vegetables are the main food sources of cadmium for humans because of their high accumulation capability. Source evaluation, detection, and remediation represent the main technologies used to clean up cadmium-contaminated sites. To mitigate the risk of cadmium contamination in freshwater, biomarker-based cadmium monitoring methods and integrated policies/strategies to reduce cadmium exposure merit further concern.

Cadmium pollution has become a serious environmental issue due to its toxicity and frequent entrance into environment components such as soil, water, and air via many anthropogenic sources. Over the last two decades, whole-cell bacterial bioreporters have been acknowledged as bio-sentinels for the determination of toxic heavy metals. Herein a sensitive and quite specific bacterial bioreporter was developed to cope with the need for the rapid and simple determination of cadmium. The construction and characterization of a fluorescence-based whole-cell cadmium bioreporter strain, Escherichia coli MG1655 (pBR-PzntA), was described which is based on the expression of green fluorescent protein under the control of the zntA gene promoter of heavy metal resistance determinant. The developed bioreporter was able determine cadmium at 5 mu g/L after 3.5 hours of induction in a defined medium while the cadmium detection limit was improved to 2 mu g/L after 1.5 hours by the use of an inorganic phosphate-limiting defined medium. Drastic changes in cadmium sensitivity were obtained between bioreporter cells induced at different growth phases. The maximum fluorescence performance was obtained for early exponential growth phase cells. This cadmium bioreporter was found to be more sensitive and specific to cadmium ions than to a wide range of heavy metals and was sensitive to only cadmium at drinking water quality standard concentrations. These findings will lead to future studies including integration of the bioreporter cells into a portable device to assess bioavailable cadmium levels in environmental samples which will provide a rapid and practical field detection technique.

Microbial remediation is a promising technique to reduce Cd accumulation in rice (Oryza sativa). In present study, a set of pot experiments were conducted to evaluate the effects of Cd-tolerate Pseudomonas TCd-1 inoculation on rice Cd uptake, soil enzyme activities and Cd bioavailability in the rhizosphere soils under Cd contaminated conditions. The results showed that at the ripening stage, with the inoculation of TCd-1, Cd contents in root, culm, leaf, hull and brown rice significantly reduced by 60.7%, 47.7%, 50.6%, 58.1% and 47.9%, respectively, and the cadmium bioconcentration factor (BCF) of rice lowered by 66.2% under 5 mg kg−1 Cd treatment. At the meantime, in the rhizosphere soils, pH increased by 0.05, the contents of exchangeable Cd (EX-Cd) and Fe-Mn oxides (OX-Cd) increased by 107.8% and 33.5%, whereas organic matter (OM-Cd) and residual (Res-Cd) decreased by 31.9% and 60.0%, respectively. The activity of acid phosphatase (ACP) increased by 28.3%, catalase (CAT), saccharase (SUC) activity decreased by 28.5% and 26.0%. Similarly, the Cd contents in root, culm, leaf, hull and brown rice reduced by 42.1%, 42.5%, 58.0%, 50.3%, and 68.8%, respectively, and the BCF lowered by 57.1%, under 10 mg kg−1 Cd treatment. Simultaneously, the soil pH increased by 0.06, the activities of CAT, SUC, urease (URE), ACP decreased by 26.4%, 34.6%, 63.8% and 15.3%, respectively. Furthermore, the correlation analysis showed that the inoculation of TCd-1 changed the correlation between rice Cd content and the biomass of roots, leaves, soil pH, CAT, PPO, URE activities, OM-Cd in rhizosphere soils. It suggested that Pseudomonas TCd-1 effectively reduced Cd uptake and Cd accumulation in rice was closely linked to the changes of soil pH, enzyme activities and Cd availability.

Eutrophication and metal pollution are global environmental problems. The risk of metal pollution is high in the eutrophic lakes because of high mobility of metal in sediments. However, the mechanism of cadmium (Cd) mobility in sediments is still unclear. Here we study the mobilization of Cd in sediments from the eutrophic Lake Taihu via monthly field monitoring of mobile Cd using diffusive gradient in thin films (DGT) and high resolution dialysis (HR-Peeper) techniques. We found a high mobility of Cd in sediments in February and March, resulting from reductive dissolution of Mn oxide mediation by high microbial activities, as shown by the similarities in distribution patterns of DGT-labile Cd and Mn. A two orders of magnitude increase in dissolved Cd concentrations (about 28 μg L−1) was observed in May and June, with dissolved Cd concentrations in overlying water about 110 times higher than the criteria continuous concentration set by Environmental Protection Agency. Hourly changes were found to coincide and correlate between dissolved Cd and dissolved organic matter (DOM) under simulated anaerobic conditions, strongly suggesting that the sudden outbreak of Cd pollution observed in the field resulted from the complexation of DOM with Cd in sediments. This was further supported by the NICA-Donnan model that more than 71% of dissolved Cd in the pore water in May and June was present as Cd-DOM complexes. Three components of DOM including humic-, tryptophan-, and tyrosine-like components in the sediments in June was identified using the fluorescence excitation emission matrix-parallel factor analysis. We found that Cd was stable complexed with tyrosine-like component. The Fourier transform infrared and two-dimensional correlation spectroscopy further revealed that Cd was bound to phenolic O H, alkene C C, alcoholic C O, aromatic C H, and alkene CH groups. Our study effectively promotes the understanding of Cd mobilization in sediments and highlights the risk of sudden Cd pollution events in the eutrophic lakes.

Predicting and analyzing the future possible scenario of the sudden water pollution accident can help emergency managers to get know the possible future of the accident and make response. In this paper, the Bayesian Network (BN) is extended to support emergency decision for sudden water pollution accidents. Three types of node variables for BN are built according to the characteristics of sudden water pollution accident. Then, the directed acyclic graph (DAG) is constructed to connect the variables. Through Estimating of the conditional probability of BN, the possible scenario of sudden water pollution accident can be formed based DAG and BN. Finally, the Longjiang River cadmium pollution in Guangxi Province is given to illustrate the feasibility and validity of the proposed method. The results show that the BN can give the possible scenario of the sudden pollution accident and can help emergency managers to make detailed alternatives further to minimize the losses.

The study was conducted in the Department of biology - College of Education for Girls - University of Anbar in order to study the effect of cadmium and lead pollution and nitrogen fertilizer sources on the accumulation of heavy metals in the root, the vegetative part, yield and its components of barley (Hordeum vulgare L.) during growing season 2020-2021, Where the experiment was carried out in pots containing 20 kg of soil. The experiment was designed according to a randomized complete block design and in the order of factorial experiments with three replications. The experiment included two factors, the first factor is three concentrations of the elements lead and cadmium (0, 40, 80 mg liter -1), and the second factor is three types of nitrogen fertilizer sources are (ammonium sulfate (NH4)2SO4, ammonium nitrate NH4NO3 and urea CO(NH2)2). The experiment was planted and irrigated with the three nitrogen fertilizer sources on 1/11/2020. After 14 days of planting, heavy metals were added to the soil in the above-mentioned concentrations in the form of two batches. The weight of 1000 grains/g and the concentration of heavy elements (Pb, Cd) in the root, vegetative and grains after harvest were calculated. The results of the study showed: The barley plant had the ability to accumulate heavy elements in the different parts of the plant, and their concentration in the root system was the highest, then the vegetative system, then the grain. However, the accumulated amounts of lead were less than cadmium in the roots, as the highest concentrations of lead and cadmium in the roots were (24.78 and 37.22 mg kg-1) and (61.13 and 92.3 mg kg-1). for the concentrations (40 and 80 mg L-1) respectively.

Simple Summary Generally, plants undergo a series of oxidative damage and even die after being stressed by cadmium (Cd). Recently, numerous studies about hyperaccumulators that can tolerate and enrich cadmium in the environment have been reported, revealing its potential in restoration of heavy metal pollution. However, there is a lack of systemic understanding of the mechanisms of Cd accumulation and detoxification by hyperaccumulators. Therefore, the purpose of this review is to investigate how these plants absorb, transport, and distribute Cd. The role of plant roots, compartmentalization, chelation, antioxidants, stress, and osmotic adjustment in bioaccumulation of Cd are comprehensively discussed. This review contributes to further understanding the mechanisms of plant enrichment and detoxification of heavy metals. Abstract The heavy metal cadmium (Cd), as one of the major environmentally toxic pollutants, has serious impacts on the growth, development, and physiological functions of plants and animals, leading to deterioration of environmental quality and threats to human health. Research on how plants absorb and transport Cd, as well as its enrichment and detoxification mechanisms, is of great significance to the development of phytoremediation technologies for ecological and environmental management. This article summarises the research progress on the enrichment of heavy metal cadmium in plants in recent years, including the uptake, transport, and accumulation of Cd in plants. The role of plant roots, compartmentalisation, chelation, antioxidation, stress, and osmotic adjustment in the process of plant Cd enrichment are discussed. Finally, problems are proposed to provide a more comprehensive theoretical basis for the further application of phytoremediation technology in the field of heavy metal pollution.

Cadmium (Cd) is a hazardous environmental pollutant with high toxicity to plants, which has been detected in many wetlands. Clonal integration (resource translocation) between connected ramets of clonal plants can increase their tolerance to stress. We hypothesised that clonal integration facilitates spread of amphibious clonal plants from terrestrial to Cd-contaminated aquatic habitats. The spread of an amphibious grass Paspalum paspaloides was simulated by growing basal older ramets in uncontaminated soil connected (allowing integration) or not connected (preventing integration) to apical younger ramets of the same fragments in Cd-contaminated water. Cd contamination of apical ramets of P. paspaloides markedly decreased growth and photosynthetic capacity of the apical ramets without connection to the basal ramets, but did not decrease these properties with connection. Cd contamination did not affect growth of the basal ramets without connection to the apical ramets, but Cd contamination of 4 and 12 mg·l-1 significantly increased growth with connection. Consequently, clonal integration increased growth of the apical ramets, basal ramets and whole clones when the apical ramets were grown in Cd-contaminated water of 4 and 12 mg·l-1 . Cd was detected in the basal ramets with connection to the apical ramets, suggesting Cd could be translocated due to clonal integration. Clonal integration, most likely through translocation of photosynthates, can support P. paspaloides to spread from terrestrial to Cd-contaminated aquatic habitats. Amphibious clonal plants with a high ability for clonal integration are particularly useful for re-vegetation of degraded aquatic habitats caused by Cd contamination.

In this paper, the method based on 2-tuple linguistic is proposed to evaluate the adaptability of the emergency response plan. In this model, dynamic weights are introduced to empress different stages of the emergency. The variables are constructed to measure the correlation between the indexes in the method. Also, the indexes are constructed to evaluate the adaptability of the emergency response plan according to the characteristics of the emergency. For illustration and verification purposes, the case of sudden event from the Longjiang River cadmium pollution of Guangxi province in China is presented. Experimental results obtained demonstrate that the proposed 2-tuple linguistic methodology can improve the evaluation for the adaptability of emergency response plan.

We assessed Cichorium intybus L. (chicory) growth, nutrients and Cd uptake in the presence of arbuscular mycorrhizal fungi (AMF), biochar (BC) and nitrogen (N) fertilizer applications in experimental pot studies. Mycorrhizal colonization was improved by BC addition but not N addition. However, in the presence of AMF, BC and N had positive effects on shoot biomass and plants grown in the presence of all 3 components yielded the highest levels of shoot biomass compared to pair-wise combinations or individual components singly added. AMF inoculation also increased root biomass and this effect was apparent in the combinations that included AMF without BC. Fungal inoculation also led to increased contents of phosphorus (P), magnesium (Mg) and copper (Cu) in both chicory shoots and roots and potassium (K) and manganese (Mn) in roots. Moreover, in the presence of BC, AMF inoculation evidently enhanced the shoot Ca content. In contrast, the presence of AMF inhibited plant Cd absorption and BC addition further inhibited root Cd concentration following the AMF inoculation. Applying N fertilizer alone increased Cd transfering from soil to plants. However, when combined with use of AMF and BC, Cd toxicity to plants was reduced. This study demonstrated that AMF inoculation combined with BC and N fertilizer could improve chicory growth, nutrient absorption and reduction of Cd uptake in Cd-contaminated soil.

Flavonoids participate in several plant processes such as growth and physiological protection in adverse environments. In this study, we investigated the combined effects of eCO2 and cadmium (Cd)-contaminated soils on the total flavonoid and monomer contents in the leaves of Robinia pseudoacacia L. seedlings. Elevated CO2, Cd, and eCO2+ Cd increased the total flavonoids in the leaves relative to the control, and eCO2 mostly increased (p

The rice-fish coculture system (RFS) is one of the most important and environmentally friendly agricultural systems in the world. With the increasing amounts of heavy metal contamination in the soil and water, the safe production of RFS has been greatly threatened. However, there are no reports on heavy metal uptake by rice and fish in a RFS. In this study, a model of cadmium (Cd)-contaminated RFS with the addition of 0–40.00 mg kg−1Cd was simulated in the field. The accumulation of Cd in the rice and fish increased as the level of Cd contamination increased. Regardless of the level of contamination, the order of Cd accumulation in the rice was root > stem ≈ leaf > rice grain > brown grain and in the fish was liver ≈ gut > kidney > gill > muscle. The dissolved oxygen (DO) and the transparency of water were significantly reduced after the fish were added. The tendency of the Cd to accumulate in the fish correlated with the change of the concentration of Cd in the water (P

Cadmium is a highly persistent and toxic heavy metal that poses severe health risks to humans. Diet is the primary source of human exposure to cadmium, especially in China. Soil, as the main medium that transfers cadmium to rice, can be used as a helpful indicator to predict human exposure to cadmium in soils. There is, however, very little work that links a soil-rice transfer model with a biokinetic model to assess health risks. In this work, we introduce a multi-medium chain model based upon a soil-rice-human continuum to address this issue. The model consists of three basic steps: (i) development and validation of a soil-rice transfer model for cadmium based on 189 pairs of measured data in Wenling of Zhejiang province in Southeast China; (ii) calculation of weekly exposure based on the nationwide monitoring and survey results; (iii) linking the exposure model with a modified biokinetic model proposed with a classic biokinetic model to predict urinary cadmium, which is a biomarker to assess the health risks. Results indicated that the developed soil-rice-human transfer model predicted well the urinary cadmium levels in humans subjected to age and exposure uncertainties. We observed a maximum of 0.71 μg g−1 creatinine in males and 1.53 μg g−1 creatinine in females at 70 years old under median cadmium exposure, which was consistent with previous studies. Sensitive analysis was also conducted to detect the sensitive parameters that have the most significant influences on the output of the model. The new risk assessment strategy proposed in this work is beneficial for predicting the cumulative cadmium levels in various exposed populations so that we can quickly identify the critical areas from basic soil properties.

We investigated the biological half-life of urinary cadmium concentration (U-Cd) based on a 22-year follow-up study after cessation of environmental Cd pollution. Spot urine samples were obtained from the inhabitants (32 men and 36 women) in the target area in 1986, 1991, 1999, 2003 and 2008. These inhabitants were divided into higher or lower baseline U-Cd group by the cut-off of 5 μg l(-1) or 5 μg g(-1) creatinine. Biological half-life of U-Cd was estimated using a linear mixed model adjusted for the baseline age. In the higher baseline U-Cd groups, the estimated half-life and 95% confidence intervals were 12.4 years (9.3-18.8 years) and 11.4 years (9.3-14.6 years) for unadjusted U-Cd in men and women, respectively. For creatinine-adjusted U-Cd, they were 16.0 years (13.0-20.7 years) and 20.4 years (16.6-26.2 years) in men and women, respectively. In the lower baseline U-Cd groups, biological half-life for unadjusted U-Cd in men was solely significant (23.4 years) and longer than the corresponding half-life in the higher baseline U-Cd group. The biological half-lives of U-Cd obtained in this study were identical with the values for U-Cd or total body burden determined by a different method.

Soil samples were collected from a paddy field at Fulong village, Huanjiang County, and Cd concentrations in soils were determined. Soil Cd risk was evaluated using Nemerow index method. The results showed that the content of cadmium in soil layer of 0~20cm is 2 times than the level two standard values and 6 times than the background value of Huanjiang soil. In addition, the soil layer of 20~100cm in cadmium content did not exceed the national level two standard values, but is about 2 times the background value of soil in Huanjiang county. In addition, Cadmium pollution is mainly focused on the soil surface.

Zebrafish were exposed to 0, 2.5 and 5 μg/L cadmium (Cd) for 10 weeks, and then each group was exposed to 26 °C(control) and 32 °C (high temperature) for 7 days. 22 indicators were compared between 26 °C and 32 °C in the spleen, including body weight, LPO and NO levels, activity levels of Cu/Zn-SOD, CAT and iNOS, MTs protein levels, and mRNA levels of Nrf2, Cu/Zn-SOD, CAT, HSF1, HSF2, HSP70, MTF-1, MTs, IL-6, IL-10, IL-1β, TNF-α, iNOS and NF-κB. Most indicators were not significantly affected by heat in fish from no Cd pollution. However, almost all of indicators were responsive to heat in fish pre-exposed to Cd. Several indicators were sensitive to heat in fish pre-exposed to 2.5 μg/L Cd such as iNOS activities, and mRNA levels of iNOS and IL-10. Most other indicators were sensitive to heat in fish pre-exposed to 5 μg/L. The mRNA levels of HSP70 and MTF-1 were up-regulated by heat in fish pre-exposed to 0, 2.5 and 5 μg/L Cd. However, the magnitude of increase was the greatest in fish pre-exposed to 5 μg/L Cd. These differences between control and high temperature would serve as biomarkers to distinguish healthy from Cd-polluted group. The findings imply that metal pollution history should be carefully considered when screening heat biomarkers in fish.

Evaluating heavy metal pollution status and ecological risk in river sediments is a complex task, requiring consideration of contaminant pollution levels, as well as effects of biological processes within the river system. There are currently no simple or low-cost approaches to heavy metal assessment in river sediments. Here, we introduce a system of assessment for pollution status of heavy metals in river sediments, using measurements of Cd in the Shaocun River sediments as a case study. This system can be used to identify high-risk zones of the river that should be given more attention. First, we evaluated the pollution status of Cd in the river sediments based on their total Cd content, and calculated a risk assessment, using local geochemical background values at various sites along the river. Using both acetic acid and ethylenediaminetetraacetic acid to extracted the fractions of Cd in sediments, and used DGT to evaluate the bioavailability of Cd. Thus, DGT provided a measure of potentially bioavailable concentrations of Cd concentrations in the sediments. Last, we measured Cd contents in plant tissue collected at the same site to compare with our other measures. A Pearson's correlation analysis showed that Cd-Plant correlated significantly with Cd-HAc, (r = 0.788, P < 0.01), Cd-EDTA (r = 0.925, P < 0.01), Cd-DGT (r = 0.976, P < 0.01), and Cd-Total (r = 0.635, P < 0.05). We demonstrate that this system of assessment is a useful means of assessing heavy metal pollution status and ecological risk in river sediments.

Cadmium has wide application in industrial production, and serious environmental pollution was generated. The Sources of Cadmium in water and its harm were introduced in this paper. The bioremediation, phytoremediation, physical and chemical remediation, electrolytic repair of wastewater containing cadmium treatment technology was reviewed, and the advantages and disadvantages of each method have been elaborated. The outlook of cadmium pollution treatment in the future was put forward.

The experiment is based on cadmium pollution of Long River in Hechi Guangxi. The results shows that under existing process condition of water plants, dosing PAC separately can make removal rate of Cd2+ reach about 60%, only ensuring the inflow water containing maximum 0.01 mg/L Cd2+ reach the standard when outflowed. When the inflow water concentration of Cd2+ surpasses 0.01 mg/L, existing technology is needed to be improved. If using combined treatment with sodium carbonate and PAC, in condition the dosing quantity of sodium carbonate is 1.1 times than the theoretical molar ratio, and PAC is 15 mg/L, the removal rate of Cd2+ reach higher than 90%, making the effluent which Cd2+ exceeds the standard by 10 times reach the standard after treated, providing a new idea for emergency treatment on Cd2+ pollution of drinking water.

The aim of that publication was the presentation of previous and planned research concerning selected vascular plants and soils near Olkusz (Southern Poland). The extremely high concentration of heavy metals in soils from that region was caused by the natural geochemical aureoles of dispersed metals (due to weathering of Zn-Pb-Fe ore sulphides) and mining and processing of shallowly occurring metalliferous deposits (containing Ag-Pb and Zn-Pb ores) since XII century. The condition of stress in metals, shortage of water and some plant nutrition led to formation of some adaptable vegetation features by plants growing in that region. Some species called metallophytes have been already detailed investigated. Moreover some geochemical and pedological research of soil have been already done. However the conditions of habitat of pioneering species such as Koeleria glauca and Corynephorus canescens are not still recognized.

With rapid socioeconomic development, water pollution emergency has become increasingly common and could potentially harm the environment and human health, especially heavy metal pollution. In this paper, we investigate the Cd pollution emergency that occurred in the Pearl River network, China, in 2005, and we build a migration and transformation model for heavy metals to simulate the spatiotemporal distribution of Cd concentrations under various scenarios of Cd pollution emergency in Foshan City. Moreover, human health hazard and carcinogenic risk for local residents of Foshan City were evaluated. The primary conclusions were as follows: (1) the number of carcinogen-affected people per year under scenario 1 reached 254.41 when the frequency was 0.1 year/time; specifically, the number of people with cancer per year in the area of the Datang, Lubao, and Nanbian waterworks was 189.36 accounting for 74% of the total number per year; (2) at the frequency of 5 years/time, the Lubao waterwork is the only one in extremely high- or high-risk grade, while besides it, the risk grade in the Datang, Nanbian, Xinan, Shitang, and Jianlibao waterworks is in the extremely high or high grade when the frequency is 0.1 year/time; (3) when Cd pollution accidents with the same level occurs again, Cd concentration decreases to a low level in the water only if the migration distance of Cd is at least 40–50 km. Based on the health risk assessment of Cd pollution, this study gives the recommendation that the distance should keep above 50 km in tidal river network of the Pearl River Delta between those factories existing the possibility of heavy metal pollution and the drinking water source. Only then can the public protect themselves from hazardous effects of higher levels of heavy metal.

Urban networks of air-quality monitors are often too widely spaced to identify sources of air pollutants, especially if they do not disperse far from emission sources. The objectives of this study were to test the use of moss bio-indicators to develop a fine-scale map of atmospherically-derived cadmium and to identify the sources of cadmium in a complex urban setting. We collected 346 samples of the moss Orthotrichum lyellii from deciduous trees in December, 2013 using a modified randomized grid-based sampling strategy across Portland, Oregon. We estimated a spatial linear model of moss cadmium levels and predicted cadmium on a 50 m grid across the city. Cadmium levels in moss were positively correlated with proximity to two stained-glass manufacturers, proximity to the Oregon–Washington border, and percent industrial land in a 500 m buffer, and negatively correlated with percent residential land in a 500 m buffer. The maps showed very high concentrations of cadmium around the two stained-glass manufacturers, neither of which were known to environmental regulators as cadmium emitters. In addition, in response to our findings, the Oregon Department of Environmental Quality placed an instrumental monitor 120 m from the larger stained-glass manufacturer in October, 2015. The monthly average atmospheric cadmium concentration was 29.4 ng/m3, which is 49 times higher than Oregon's benchmark of 0.6 ng/m3, and high enough to pose a health risk from even short-term exposure. Both stained-glass manufacturers voluntarily stopped using cadmium after the monitoring results were made public, and the monthly average cadmium levels precipitously dropped to 1.1 ng/m3 for stained-glass manufacturer #1 and 0.67 ng/m3 for stained-glass manufacturer #2.

A pot experiment was carried out by growing 29 different genotypes (Amaranthus spp.) of vegetable amaranth under low- (0.12 mg·kg−1) and middle- (0.40 mg·kg−1) cadmium (Cd) exposure. The result showed that amaranth was vulnerable to cadmium (Cd) contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant (P

Heavy metals provoke environmental pollution with potentially toxic effects on human and plants systems. Recently, investigations are conducted on plants that may play a relevant role on pollutants absorption or stabilization, focusing on fast growing tree species in agronomic conditions; little is known on the effects of contaminants on tree species colonizing abandoned fields to be used in restoration ecology. The effects of Cd on photosynthetic performance and metal accumulation were investigated in Quercus pubescens Willd. seedlings grown in pots containing a mixture of sand, clay, turf and Cd-treatments (0, 25 and 75 mg kg-1 dry soil). The studied photosynthetic parameters (Asat= net phytosynthesis; Rday= day respiration; Γcomp= CO2 compensation point; Vcmax= maximum carboxylation rate; Jmax = electron transport rate; TPU = triose phosphate use; Ci/Ca = ratio of intercellular (Ci) to ambient (Ca) [CO2] (Ci/Ca); Jmax/Vcmax = ratio; (gsmax) = maximum stomatal conductance; (lg) = stomatal conductance estimated relative to the photosynthetic rate; (Fv/Fm) = maximum quantum yield of PSII photochemistry; (ΔF/F’m) = effective photochemical efficiency) varied progressively with increasing Cd concentration in the soil, highlighting a negative impact on photosynthetic potential and PSII functioning. Approximately 10% of added Cd was found to be extractable from the substrate, at the maximum concentration applied, with about 12 and 0.75 as bioaccumulation and translocation factors, respectively. Analogously, Cd accumulated up to 34, 30 and 46 mg kg-1 in leaves, stem and roots, respectively. While it is not possible to extrapolate from the present study with seedlings to effects on mature pine trees, there are clear implications for regeneration in soils contaminated with heavy metals, which may lead to ecosystem deterioration.

After 4 days exposed to cadmium concentration environment, the soluble protein content, SOD activity, CAT activity, POD activity and MDA content of Hydrocharis Dubia root were investigated in this paper to study if this plant can be used to waterbody restoration with cadmium pollution. The result showed that when the cadmium concentration was lower than 5 mg.L-1, the plant didn’t encounter seriously oxidant damaged. The plant root cell increased SOD activity, CAT activity and POD activity to clean up these accumulated ROS. Hydrocharis Dubia can be used to waterbody restoration with lower than 5 mg.L-1 cadmium pollution. The plant unsuitable to be used to waterbody restoration with higher than 5 mg.L-1 cadmium pollution, the plant encountered seriously oxidant stress in this level cadmium pollution.

The purpose of this study was to assess the application of several bioindication methods for the monitoring of environmental pollution from Pb and Cd. The study area centered on the town of Olkusz, Poland, which is one of the oldest centers for the metallurgical industry in Europe. The assessment of environmental pollution due to metals was performed using four frequently used bioindication methods: moss-bag (Sphagnum fallax), determination of metal accumulation in Pleurozium schreberi, silver birch foliage, and Scots pine needles. The region of Olkusz, and especially the area surrounding the mining and metallurgical Bolesław complex, was extremely contaminated with Pb and Cd. The results of the investigations are presented as contamination deposition maps. Despite the application of various methods and the resulting diversity of the specific exposure periods for different biomonitors, the spatial distribution of contamination shown on the maps was similar, as confirmed by the statistical analysis of the results.

Cadmium (Cd) pollution in the suburbs of Tianjin, China, was monitored over a period of several years. During this period, 193 soil, 120 vegetable, and 71 rice samples from four suburban districts were analyzed. The Cd content of the soil samples was considerably higher than the background level. Some soil samples from the Dongli and Xiqing districts were even in the S5 (Heavy) and S6 (Severe) pollution levels, with a maximum concentration of 5.20 mg kg−1. The Cd contents of vegetable and rice samples were found to be in the F3 (Intermediate) and F4 (Heavy) pollution levels. Vegetables showed differing abilities to accumulate Cd and can be ranked in the following order: leaf vegetables > rootstalk vegetables > fruit vegetables. The average Cd level in different vegetables ranged from 0.0064 to 0.132 mg kg−1, and a positive relationship (p < 0.05) was found between soil and plant Cd contents. Chinese cabbage and celery were more likely to pose risks to human health, as shown by their higher hazardous quoti...

The pot experiment grown with cabbage was conducted. The initial soil and six incubated soils with different total Cd (0.25, 0.78, 1.3, 3.18, 5.34 and 7.11mg Cd/kg soil) were used in the pot experiment. The present study was to examine cadmium (Cd) accumulation in edible parts of cabbage and its correlation with Cd concentrations in cabbage garden soil, and evaluate the bioavailability and toxicity of Cd accumulating in cabbage by a human intestinal cell culture model (Caco-2). The results showed that Cd accumulation of cabbage was linearly correlated with Cd concentration in grown soils. Cd uptake of Caco-2 cells increased gradually with increasing level of Cd accumulation in cabbage. MTT assay investigation suggested that viability of the Caco-2 cells reduced with Cd accumulation in cabbage. In comparison with the control group, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the experiment groups decreased as treated with Cd contaminated cabbages, and there was significant difference in partial groups (p < 0.05). At levels of 47.69mg Cd kg-1 accumulated in cabbage, the value of T-AOC of cells decreased significantly (p < 0.05), while the content of MDA in cells was significantly higher than that in other groups. The results suggested that Cd concentrations in the edible parts of test cabbage crops were linearly responded to the Cd levels in the growth soil, and toxicological effect of Cd to Caco-2 cells aggravated gradually with Cd accumulation increased in cabbage.

Based on the available data obtained from the population investigating, the authors reviewed research articles of the study on analytical me- thods and exposure levels of cadmium (Cd) in population, the injury of target organ, the evol- vement of sensitive index for surveillance, the study on effects of human disease and death for environmental Cd exposure, and the study on priority surveillance of human health risk.

Although bodies of water are a major vehicle for cadmium contamination, works dealing with submerged plants directly exposed to it are still very scarce. The aim of this research was to study damaging effects of prolonged cadmium exposure on young and mature submerged leaves of Elodea canadensis treated for 1 month with 100 μM Cd added to the growth water medium. The Cd-exposed plants, compared to the controls, showed shorter and poorly pigmented shoots with thinner stems and less expanded leaves. The leaves accumulated high quantities of cadmium, most of which, about 95 and 90% in young and mature leaves, respectively, remained outside the cells, bound to the anionic cell walls. In young differentiating leaves, Cd interfered with the morphogenetic pattern, by inhibiting cell division and affecting cell enlargement. Cd hindered the division and the expansion of chloroplasts, also impairing organelle shape and thylakoid system arrangement. Cadmium, furthermore, greatly disturbed the cell wall organization, causing the demolition of the transfer cell-like frame. In differentiated leaves, Cd hastened the appearance of senescence symptoms in chloroplasts and worsened the cell wall alterations. Both young and mature leaves showed a decreased photosynthetic activity, not only ascribable to lowered chlorophyll contents.

Toxicity and accumulation of cadmium in body organs by eating contaminated food has an important role in endangering a human's health. Using Environmental Protection Agency (EPA) reports, site 1, site 2 and site 3 were selected as polluted sites and site 4 was selected as the control site. Seedlings of buttonwood were prepared for 12 months then root, stem, and leaf samples were harvested and the amounts of cadmium element in stem and leaf organs together with the growth parameters were measured. This study determines the amount of cadmium accumulated in Platanus occidentalis. The respective cadmium concentrations in the root, leaf, and stem in site 1 were 382, 98, and 87; in site 2 they were 591, 122, and 94; and in site 3 they were 633, 151, and 104 mg/kg dry weight (DW). Furthermore, the comparison between accumulation and transfer of cadmium in the study showed more absorption of this metal by the root than that by the stem and leaf. The result of this research shows that buttonwood has the potential for cadmium accumulation without any serious damage to its growth. To control the extent of contamination in industrial areas, petrochemical industries, power plants and vast contaminated municipal areas, there is a great need for planting plants like buttonwood.

Serum cadmium levels at delivery were measured in a consecutive sample of 100 mother-infant pairs in Egypt using venous blood from mothers and umbilical cord blood from neonates. The serum cadmium levels of mothers ranged from 0.4 to 2.2 microg/L [mean 0.73 microg/L] and of infants from 0.2 to 1.5 microg/L [mean 0.66 microg/L]. Infant cadmium levels were about 70% of maternal levels in most pairs. Serum cadmium was significantly higher in mothers and babies passively exposed to tobacco smoke. Five-minute Apgar scores were negatively correlated with cord blood cadmium levels. The cadmium levels did not differ between subjects from Cairo and Giza or according to urban, suburban or rural areas. Thus, in utero exposure to cadmium was evident and wider-scale studies on its long-term effects are recommended.

A pot experiment and a sandy culture experiment grown with three vegetable crops of Chinese cabbage (B. chinensis L. cv. Zao-Shu 5), winter greens (B. var. rosularis Tsen et Lee cv. Shang-Hai-Qing), and celery (A. graveolens L. var. dulce DC. cv. Qing-Qin) were conducted, respectively. The initial soil and four incubated soils with different extractable cadmium (Cd) levels (0.15, 0.89, 1.38, 1.84, and 2.30 mg Cd kg−1 soil) were used for the pot experiment. Five treatments were designed (0, 0.0625, 0.125, 0.250, and 0.500 mg Cd L−1) in nutrient solution in the sandy culture experiment. Each treatment in both pot and sandy culture experiments was trireplicated. The objectives of the study were to examine Cd accumulation in edible parts of selected vegetable crops, its correlation with Cd concentrations in vegetable garden soil or in nutrient solution, and to evaluate the criteria of Cd pollution in vegetable garden soil and in nutrient solution based on the hygienic limit of Cd in vegetables. Cadmi...

The Itai-Itai disease case is one of four major pollution-related lawsuits occurring in Japan after World War II. This paper, which is based on investigations of the pollution source, the Kamioka mine, considers (1) the history of the disturbances to the environment caused by the Kamioka mine; (2) the Itai-Itai disease suit; (3) the pollution-prevention measures and methods of the Kamioka mine and refinery; (4) the reduction of cadmium pollution in the Jinzu River; and (5) the actual application of the “polluter pays principle”. The authors conclude that the court decision and the agreements between the victims and Mitsui Mining made it possible to control and reduce the damage caused by cadmium pollution and four additional, contributory factors.