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Understanding the prevalent form of platinum (Pt) based antineoplastic agents, used in chemotherapy, is of importance to develop a remediation strategy that restricts aquatic exposure. The speciation of Pt-based compounds was measured in actual patients’ urine using hydrophobic interaction liquid chromatography (HILIC) equipped with an ICP-MS detector. Carboplatin showed poor metabolization and intact excretion 11 h after administration, whereas cisplatin underwent a rapid aquation in the first 7 h. To compare, the in vitro degradation rate of cisplatin, carboplatin and oxaliplatin was determined in synthetic human urine, mimicking true environmental conditions. The fraction of intact molecules was measured at regular intervals following incubation at 37 °C, resulting in degradation rate constants. The chemical stability was highest for carboplatin (k = 0.0143 ± 0.0012 min−1), versus faster degradation of oxaliplatin and cisplatin by exponential decay with k1 of 0.0026 ± 0.0001 min−1 and k2 = 5.59 ± 0.46 × 10−6 min−1, respectively. These kinetic parameters can serve as input to further expand modelling databases and improve the predictive power of speciation software to estimate eco-toxicity risks. Considering the strong residual cytotoxicity of the platinum antineoplastic molecules following renal clearance and human excretion, the contaminants are of high environmental concern and offer potential for metal recovery using advanced treatment steps. In such water treatment processes, especially carboplatin, above all cancerostatic platinum compounds, should be addressed since it is more persistent in the aquatic environment.

The authors of this Comment are longstanding selenium investigators with a total of 200 or more published articles on selenium; the corresponding author (Margaret P [...]

BackgroundSelenium (Se) and zinc (Zn) are essential antioxidant enzyme cofactors. Foliar Se/Zn application is a highly effective method of plant biofortification. However, little is known about the effect of such applications on the concentration of trace elements and phytochemicals with pro-oxidant or antioxidant activity in pea (Pisum sativum L.).MethodsA 2-year pot experiment (2014/2015) was conducted to examine the response of two pea varieties (Ambassador and Premium) to foliar-administered sodium selenate (0/50/100 g Se/ha) and zinc oxide (0/375/750 g Zn/ha) at the flowering stage. Concentrations of selected trace elements (Fe, Cu, and Mn), total phenolic content (TPC), total flavonoid content (TFC), and total antioxidant activity (ABTS, FRAP) of seeds were determined.Results and conclusionsSe/Zn treatments did not improve the concentration of trace elements, while they generally enhanced TPC. Among examined treatments, the highest TPC was found in Ambassador (from 2014) treated with 100 g Se/ha and 750 g Zn/ha (2,926 and 3,221 mg/100 g DW, respectively) vs. the control (1,737 mg/100 g DW). In addition, 50 g of Se/ha increased TFC vs. the control (261 vs. 151 mg/100 g DW) in Premium (from 2014), 750 g of Zn/ha increased ABTS vs. the control (25.2 vs. 59.5 mg/100 g DW) in Ambassador (from 2015), and 50 g of Se/ha increased FRAP vs. the control (26.6 vs. 18.0 mmol/100 g DW) in Ambassador (from 2015). In linear multivariable regression models, Zn, Mn, Cu, and TPC best explained ABTS (R = 0.577), while Se, Cu, and TPC best explained the FRAP findings (R = 0.696). This study highlights the potential of foliar biofortification with trace elements for producing pea/pea products rich in bioactive plant metabolites beneficial for human health.

IntroductionCertain trace elements are essential for life and affect immune system function, and their intake varies by region and population. Alterations in serum Se, Zn and Cu have been associated with COVID-19 mortality risk. We tested the hypothesis that a disease-specific decline occurs and correlates with mortality risk in different countries in Europe.MethodsSerum samples from 551 COVID-19 patients (including 87 non-survivors) who had participated in observational studies in Europe (Belgium, France, Germany, Ireland, Italy, and Poland) were analyzed for trace elements by total reflection X-ray fluorescence. A subset (n=2069) of the European EPIC study served as reference. Analyses were performed blinded to clinical data in one analytical laboratory.ResultsMedian levels of Se and Zn were lower than in EPIC, except for Zn in Italy. Non-survivors consistently had lower Se and Zn concentrations than survivors and displayed an elevated Cu/Zn ratio. Restricted cubic spline regression models revealed an inverse nonlinear association between Se or Zn and death, and a positive association between Cu/Zn ratio and death. With respect to patient age and sex, Se showed the highest predictive value for death (AUC=0.816), compared with Zn (0.782) or Cu (0.769).DiscussionThe data support the potential relevance of a decrease in serum Se and Zn for survival in COVID-19 across Europe. The observational study design cannot account for residual confounding and reverse causation, but supports the need for intervention trials in COVID-19 patients with severe Se and Zn deficiency to test the potential benefit of correcting their deficits for survival and convalescence.

Up to 15% and 17% of the world population is selenium (Se) and zinc (Zn) deficient, respectively. Pea (Pisum sativum L.) is an important staple legume with a high potential for Se and Zn biofortification in seeds. A 2-year pot experiment investigated two pea varieties (Ambassador and Premium) following foliar-applied sodium selenate (0/50/100 g of Se/ha) and zinc oxide (0/375/750 g of Zn/ha) at the flowering stage. Selenate and zinc oxide had minimal overall effects on growth parameters. Zinc oxide did not improve Zn accumulation in both seed varieties, while selenate improved Se accumulation in both seed varieties dose-dependently. Premium accumulated greater amounts of Se in seeds than Ambassador (p < 0.001). Selenium concentrations were highest in seeds of Premium treated with 100 g of Se/ha [7.84 mg/kg DW vs. the control (0.16 mg/kg DW), p < 0.001]. The predominant Se species in Se-enriched seeds was selenomethionine (40%–76% of total Se). Furthermore, a significant (p < 0.01) positive correlation was found between Zn and S concentrations in Ambassador (r2 = 0.446) and Premium (r2 = 0.498) seeds, but not between Se and S. Consuming as little as 55 g/day of pea biofortified by 50 g of Se/ha would cover 100% of the adult RDA (55 µg) for Se. Findings are important for improving foliar biofortification of pea with Se and Zn.

Though selenium (Se) and zinc (Zn) constitute essential nutrients for human health, their deficiencies affect up to 15% and 17% of the global population, respectively. Agronomic biofortification of staple crops with Se/Zn may alleviate these challenges. Pea (Pisum sativum L.) is a nutritious legume crop that has great potential for Se/Zn biofortification. Herein, two varieties of pea (Ambassador, Premium) were biofortified via foliar application of sodium selenate (0/50/100 g of Se/ha) or zinc oxide (0/375/750 g of Zn/ha) during the flowering stage under field conditions. While no significant differences were found in Se accumulation between seed varieties upon Se treatments, selenate enhanced the accumulation of Se in the two seed varieties in a dose dependent manner. Selenium concentration was most elevated in seeds of Ambassador exposed to 100 g of Se/ha (3.93 mg/kg DW compared to the control (0.08 mg/kg DW), p < 0.001). 375 g of Zn/ha (35.7 mg/kg DW) and 750 g of Zn/ha (35.5 mg/kg DW) significantly and similarly enhanced Zn concentrations compared to the control (31.3 mg/kg DW) in Premium seeds, p < 0.001. Zinc oxide also improved accumulations of Fe, Cu, Mn, and Mg in Premium seeds. Se/Zn treatments did not significantly affect growth parameters and accumulations of soluble solids and protein in seeds. Positive and significant (p < 0.01) correlations were observed between Zn and Fe, Cu, Mn and Mg levels in Premium seeds, among others. Consuming 33 g/day of pea biofortified with Se at 50 g/ha and 266 g/day of pea biofortified with 375 g of Zn/ha could provide 100% of the RDA (55 μg) for Se and RDA (9.5 mg) for Zn in adults, respectively. These results are relevant for enhancing Se/Zn status in peas by foliar biofortification.

Abstract Powdery hierarchical porous carbons serve as cost‐effective, functional materials in various fields, namely energy storage, heterogeneous catalysis, electrochemistry, and water/wastewater treatment. Such powdered activated carbons (PAC) limit new module designs and require further preparation steps, for example, adding polymeric binders, to be shaped into a standalone geometry. Polymeric binders, however, can block PACs’ catalytic and active sites and, more importantly, pose the risk of secondary pollution for environmental purposes, especially in the context of clean water supply. This study introduces a novel synthesis method for fabricating freestanding nitrogen‐doped carbons with hierarchical porosity using chitosan and sucrose as green precursors. Chitosan supplies nitrogen and acts as a backbone, giving a freestanding geometry to the final product, and sucrose is a carbon‐rich precursor. The proposed method employs ice‐ and hard‐templating for macropores and mesopores and combines carbonization and activation steps with no required activating agent. Final freestanding carbons function as adsorbents for removing persistent pollutants, as binder‐free electrodes with high specific surface area and capacitive current, and as tubular gas diffusion electrodes for oxygen reduction reactions. These freestanding carbons enable new module designs and can be scaled‐up by numbering‐up, serving as bio‐based functional materials for a wide range of applications involving porous heteroatom‐doped carbons.

Exposure to lead (Pb) through drinking water has been linked to adverse health outcomes. Children are particularly susceptible. This study was designed to measure Pb contamination level in drinking water of the Ethiopian city Addis Ababa and assess the associated health risks. Eighty-eight fully-flushed drinking water samples were collected from all ten sub-cities of Addis Ababa. Pb concentration was measured using an Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The chronic daily intake (CDI), the hazard quotient (HQ), and the cancer risk (CR) of Pb were determined to assess exposure levels and health effects. Blood lead level (B–Pb) for children was modelled using the integrated exposure uptake biokinetic model (IEUBK). The mean concentration of Pb in the drinking water was 17.8 μg/l, where >50% of the samples exceeded WHO's 10 μg/l guideline. Significant spatial variation of Pb was noticed among sub-cities. The mean CDI was 1.43 and 0.59 μg/kg/day for children and adults, respectively. The HQ showed that 8% of children and 2.3% of adults exceeded the safe limit. The predicted geometric mean of B–Pb ranged from 3.23 to 14.65 μg/dl. The risk of a child having a B–Pb level >5 μg/dl at the median water Pb concentration (10.5 μg/l) was estimated at 13.4%. Based on the 95th percentile Pb concentration (75.1 μg/l), 89.6% of children would have B–Pb levels above the 5 μg/dl threshold. The estimated CR was found in the range of 1 × 10−7 to 9.9 × 10−5; hence cancer risks are not a concern. The study concluded that Addis Ababa's drinking water is likely to be a source of lead exposure where consumers at specific city locations are at risk of numerous non-cancer health effects. The impacts are expected to be severe in the Ethiopian context; hence further investigations and coordinated interventions are required.

Abstract Freeze desalination, i.e., desalination of water by freezing it, may be an option to treat polluted water at individual household level. Taking into account the widespread fluoride contamination of Ethiopian water resources and with the reason that most households in semi-urban and urban areas do have easier accessibility of refrigerators, this study aimed to investigate the defluoridation capacity of freeze desalination and its energy consumption for different water sources. For this purpose, synthetic solutions that emulate the major ion compositions of natural waters (hereafter called simulated water), tap water, and double-distilled water to which variable concentrations of fluoride ions were added were evaluated using home-use insulated refrigerator (BEKO, RRN 2650). The effects of conditions such as initial fluoride concentration, multi-ion existence, fraction of ice frozen, volume of the container, and freezing duration were evaluated in relation to the produced ice quality. It was found that nearly 48% and 62% removal of fluoride were achieved from tap water spiked with 10 mg/L F− and 10 mg/L F− aqueous solutions, respectively, with a total water recovery of 85 to 90%. The energy consumption predicted to produce the ice from tap water spiked with 10 mg/L F− and double-distilled water alone was found to be 93.9 and 91.8 kJ/L, respectively. The results showed that freeze desalination can be a potential technique for fluoride removal from water to be used as drinking water at household level in semi-urban and urban areas as well as in colder regions.

Selenium (Se) and zinc (Zn) are important cofactors for antioxidant enzymes. Foliar Se/Zn application is a highly efficient strategy of plant biofortification. However, its effects on the accumulation of macrominerals, macronutrients and bioactive compounds in the pea plant (Pisum sativum L.) have been poorly investigated. A two-year pot experiment was performed to study responses of two pea varieties (Ambassador, Premium) to foliar-applied sodium selenate (0/50/100 g Se/ha) and zinc oxide (0/375/750 g Zn/ha) at the flowering stage. Concentrations of Ca, Mg, K, Na, soluble solids (SSC), protein, chlorophyll a and b, total chlorophyll, total carotenoids and total condensed tannins (TCT) were determined in seeds. Mg concentration in Ambassador and chlorophyll a concentration in Premium were positively affected, in part, by selenate and zinc oxide, respectively. Selenate and zinc oxide increased, in part, protein concentration in Premium. Highest protein concentration was found in Premium treated with 375 g Zn/ha (27.6% DW) vs. the control (26.6% DW). Significant (all p < 0.001) positive correlations were found, among others, between concentrations of Zn and Mg (r2 = 0.735) and between Zn and protein (r2 = 0.437) for Ambassador, and between Mg and protein (r2 = 0.682), between Zn and Mg (r2 = 0.807), as well as between Zn and protein (r2 = 0.884) for Premium. TCT significantly (all p < 0.05) and positively correlated with SSC (r2 = 0.131), chlorophyll b (r2 = 0.128) and total chlorophyll (r2 = 0.109) for Ambassador. This study provides new nutritional data on Se/Zn biofortified peas, important for improving agronomic biofortification of pea plants.

A study to quantify the toxicity and ecotoxicological pressure of pesticides in the Sancti Spíritus province, Cuba, was carried out between 2011 and 2014. A longitudinal descriptive work was designed for the study period to identify potential risks to the environment and also to human health associated with the use of pesticides in the country. The Spread Equivalents (ƩSeq) and Pesticide Occupational and Environmental Risk (POCER) indicators, as well as the Toxic Load (TL) methodology of Instituto Cubano de Sanidad Vegetal, were used to determine the toxicity and ecotoxicity of pesticide use. One hundred and twenty-four active ingredients corresponding to 62 chemical families were applied in the province during the study period. Organophosphates, triazoles, sulfonylurea, pyrethroids, inorganic compounds (such as copper), carbamates, dithiocarbamates, neonicotinoids, aryloxyphenoxypropionates, and organochlorines predominated due to their use frequency. The use of toxic pesticides, and the lack of personal protection equipment, among others, made workers, residents, and applicators the toxicological modules with the highest risk of exposure. On the other hand, aquatic organisms, and the persistence of the pesticides in the soil and in groundwater, are the modules with the highest ecotoxicological pressure. By using the POCER and ƩSeq indicators, a more accurate toxicity and ecotoxicity assessment for certain pesticides can be performed in Cuba, in comparison to the one obtained when using only the TL equation currently employed in the country. In addition, substituting the most toxic pesticides (e.g., parathion, endosulfan, bifenthrin, copper oxychloride, mancozeb, paraquat, diquat, and ametryn) with less toxic ones (e.g., cypermethrin, tebuconazole, triadimenol, and bispyribac-sodium) could help reduce synthetic pesticide pressure on humans and the environment.

Aim of study: To quantify the toxicity and ecotoxicological pressure of pesticides in Sancti Spíritus province, Cuba, between 2011 and 2014. Material and methods: A longitudinal descriptive study was designed for the study period, to identify potential risks to the environment and human health associated with the use of pesticides. In order to determine the toxicity and ecotoxicity of pesticide use, ƩSeq (Spread equivalents), POCER (Pesticide Occupational and Environmental Risk) indicator, and the Toxic Load (TL) methodology of the Plant Health Cuban Institute were used. Main results: Corresponding to 62 chemical families, 124 active ingredients were applied in the province during the study period. Organophosphates, carbamates, pyrethroids, inorganic compounds (such as copper), dithiocarbamates, aryloxyphenoxypropionates, neonicotinoids, sulfonylurea, triazoles, and organochlorines predominated due to their frequency of use. Use of toxic-pesticides, lack of personal protection equipment amount others made workers, residents and applicators the toxicological modules with the highest risk of exposure. From the POCER results we found that aquatic organisms, persistence, and groundwater are the modules with the highest ecotoxicological pressure. Research highlights: With the use of the POCER indicator as well as ƩSeq, a more accurate assessment of toxicity and ecotoxicity from certain pesticide can be done instead of the TL equation currently used in Cuba. In addition substitution of the most toxic pesticides by less toxic ones could help to reduce synthetic pesticide pressure on humans and the environment. This study can help to develop policies and management practices to reduce the hazards of synthetic pesticide use in Cuba.

The aim of this work was to study the redox-induced mobilization of Ag, Sb, Sn, and Tl in the dissolved, colloidal, and sediment phase of a mining soil treated and untreated with biochar as affected by the redox potential (EH) -dependent changes of soil pH, dissolved organic carbon, Fe, Mn and S. The experiment was conducted stepwise at two EH cycles (+200 mV → -30 mV → +333 mV → 0 mV) using biogeochemical microcosm. Silver was abundant in the colloidal fraction in both cycles, indicating that Ag might be associated with colloids under different redox conditions. Antimony, Sn and Tl were abundant in the colloidal fraction in the first cycle and in the dissolved fraction in the second cycle, which indicates that they are retained by colloids under oxic acidic conditions and released under reducing alkaline conditions. Release of dissolved Sb, Sn, and Tl was governed positively by pH, Fe, S, and dissolved aromatic compounds. Biochar mitigated Ag release, but promoted Sb, Sn, and Tl mobilization, which might be due to the wider range of EH (-12 to +333) and pH (4.9–8.1) in the biochar treated soil than the un-treated soil (EH = -30 to +218; pH = 5.9–8.6). Also, the biochar surface functional groups may act as electron donors for the Sb, Sn, and Tl reduction reactions, and thus biochar may play an important role in reducing Tl3+ to Tl+, Sb5+ to Sb3+, and Sn4+ to Sn2+, which increase their solubility under reducing conditions as compared to oxic conditions. Thallium and Sb exhibit higher potential mobility in the solid phase than Sn and Ag. Biochar increased the potential mobility of Sb, Sn, and Tl under oxic acidic conditions. The results improve our understanding of the redox-driven mobilization of these contaminants in soils.

Off-label use of pesticides (i.e. application at inappropriate times and/or on unregistered crops) is a potential risk to the environment and human health. The objective of this study was to assess the level of knowledge and awareness of small lot farmers on the use, risk, and hazards associated with exposure to pesticides in the agricultural region of Sancti Spíritus, Cuba. For the fulfillment of the objective, 124 small lot farmers of the province were surveyed. The results were analyzed from an initial descriptive analysis and then through an association analysis using the Chi-Square test and Spearman correlations, with the use of the statistical package SPSS version 20.0. The results showed that only 28.3 % of the farmers had received specific training on pesticides. Personal experience was the main driver for decisions about which pesticides to use and how to apply them. 35.8 % of the farmers stored pesticides in unmarked containers, such as soft drink bottles. The empty containers are stored to be incinerated (31.7 %) or reused (42.6 %) for pesticides, water, or fuel. Around 90 % of farmers do not use personal protection equipment. The study concludes that the lack of knowledge and personal protective equipment, inability to understand the labels, and low risk-perception are the main causes of exposure to pesticides and the health risk for workers and nearby residents, as well as damage to the environment.

Selenium (Se) and zinc (Zn) are essential trace elements needed for appropriate immune system responses, cell signalling and anti-viral defence. A cross-sectional observational study was conducted at two hospitals in Ghent, Belgium, to investigate whether Se and/or Zn deficiency upon hospital admission correlates to disease severity and mortality risk in COVID-19 patients with or without co-morbidities. Trace element concentrations along with additional biomarkers were determined in serum or plasma and associated to disease severity and outcome. An insufficient Se and/or Zn status upon hospital admission was associated with a higher mortality rate and a more severe disease course in the entire study group, especially in the senior population. In comparison to healthy European adults, the patients displayed strongly depressed total Se (mean ± SD: 59.2 ± 20.6 vs. 84.4 ± 23.4 µg L−1) and SELENOP (mean ± SD: 2.2 ± 1.9 vs. 4.3 ± 1.0 mg L−1) concentrations at hospital admission. Particularly strong associations were observed for death risk of cancer, diabetes and chronic cardiac disease patients with low Se status, and of diabetes and obese patients with Zn deficiency. A composite biomarker based on serum or plasma Se, SELENOP and Zn at hospital admission proved to be a reliable tool to predict severe COVID-19 course and death, or mild disease course. We conclude that trace element assessment at hospital admission may contribute to a better stratification of patients with COVID-19 and other similar infectious diseases, support clinical care, therapeutic interventions and adjuvant supplementation needs, and may prove of particular relevance for patients with relevant comorbidities.

Mangrove wetlands provide essential ecosystem services such as coastal protection and fisheries. Metal pollution due to industrial and agricultural activities represents an issue of growing concern for the Guayas River Basin and related mangroves in Ecuador. Fisheries and the related human consumption of mangrove crabs are in need of scientific support. In order to protect human health and aid river management, we analyzed several elements in the Guayas Estuary. Zn, Cu, Ni, Cr, As, Pb, Cd, and Hg accumulation were assessed in different compartments of the commercial red mangrove crab Ucides occidentalis (hepatopancreas, carapax, and white meat) and the environment (sediment, leaves, and water), sampled at fifteen sites over five stations. Consistent spatial distribution of metals in the Guayas estuary was found. Nickel levels in the sediment warn for ecological caution. The presence of As in the crabs generated potential concerns on the consumers’ health, and a maximum intake of eight crabs per month for adults is advised. The research outcomes are of global importance for at least nine Sustainable Development Goals (SDGs). The results presented can support raising awareness about the ongoing contamination of food and their related ecosystems and the corresponding consequences for environmental and human health worldwide.

Soil salinity is one of the important abiotic stress factors that affect rice productivity and quality. Research with several dicotyledonous plants indicated that the detrimental effects associated with salinity stress can (partly) be overcome by the external application of antioxidative substances. For instance, sodium selenate (Na2SeO4) significantly improved the growth and productivity of several crops under various abiotic stress conditions. At present there is no report describing the impact of Na2SeO4 on salinity stressed cereals such as rice. Rice cultivation is threatened by increasing salinity stress, and in future this problem will further be aggravated by global warming and sea level rise, impacting coastal areas. The current study reports on the effect of Na2SeO4 in alleviating salinity stress in rice plants. The optimal concentration of Na2SeO4 and the most efficient mode of selenium application were investigated. Selenium, sodium, and potassium contents in leaves were determined. Antioxidant enzyme activities as well as proline, hydrogen peroxide (H2O2), and malondialdehyde (MDA) concentrations were analyzed. In addition, the transcript levels for OsNHX1, an important Na+/H+ antiporter, were quantified. Treatment of 2-week-old rice plants under 150 mM NaCl stress with 6 mg l-1 Na2SeO4 improved the total biomass. A significantly higher biomass was observed for the plants that received Na2SeO4 by a combination of seed priming and foliar spray compared to the individual treatments. The Na2SeO4 application enhanced the activity of antioxidant enzymes (SOD, APX, CAT, and GSH-Px), increased the proline content, and reduced H2O2 and MDA concentrations in plants under NaCl stress. These biochemical changes were accompanied by increased transcript levels for OsNHX1 resulting in a higher K+/Na+ ratio in the rice plants under NaCl stress. The results suggest that Na2SeO4 treatment alleviates the adverse effect of salinity on rice plant growth through enhancing the antioxidant defense system and increase of OsNHX1 transcript levels.

This study evaluates the differences in mineral and toxic trace element concentrations of Nile tilapia (Oreochromis niloticus) tissues from three aquatic ecosystems in Ethiopia—Lake Ziway, Lake Langano, and Gilgel Gibe reservoir—with a focus on edible (fillet) and discarded (digestive tract, gills, skin, and liver) parts. A total of sixty (n = 60) Nile tilapia samples were collected, comprising twenty (n = 20) fish from each lake, and analyzed by inductively coupled plasma mass spectrometry. All elements varied markedly among tissues and between the lakes. Some differences in element concentrations were attributed to differences in nutrient load in the ecosystems and the function of the tissues. For instance, the calcium concentrations in skin and gill were distinctly higher in fish from calcium-rich Lake Langano. The d iscarded parts were richer in essential trace elements, showing an opportunity to promote their use in human nutrition to increase the intake of important minerals. However, the accumulation of elements toxic to humans, such as aluminum, should be monitored and, in particular, controlled when rearing these fish in aquaculture.

Changes in the hydrology of sediments in tidal marshes or landfills may affect the uptake of metals in the vegetation. Leaf and stem samples of Salix cinerea (grey sallow) were collected during four consecutive growing seasons at six contaminated plots on a polluted dredged sediment landfill and one plot on an uncontaminated reference site. The first three contaminated plots were already emerged in the first half of the first growing season, while the other three were submerged in the first year, but became increasingly dry over the study period. Foliar and stem cutting concentrations for Cd, Zn and Mn increased on the latter three plots over the four years. Willow bark contained high concentrations of Cd, Zn and Mn. In two consecutive greenhouse experiments with willow cuttings from different origins (uncontaminated and contaminated sites) and grown under different soil conditions (uncontaminated and contaminated), we observed an important translocation of Mn from bark to shoots. In a third experiment with willow cuttings collected on soils with a range of heavy metal concentrations and, thus, with a broad range of Cd (4–67 mg/kg dry matter), Zn (247–660 mg/kg dry matter) and Mn (38–524 mg/kg dry matter) concentrations in the bark, high Mn concentrations in the bark were found to affect the budburst of willow cuttings, while no association of delayed budburst with Cd and Zn concentrations in the bark was found. We conclude that wood and, especially, bark are not a sink for metals in living willows. The high Mn concentrations in the bark directly or indirectly caused delayed or restricted budburst of the willow cuttings.

There is a growing concern for the long-term health effects of selenium (Se) over- or underfeeding. The efficiency of utilization of dietary Se is subject to many factors. Our study in dogs evaluated the effect of diet type (canned versus kibble) and dietary protein concentration on Se digestibility and bioactivity. Canned and kibble diets are commonly used formats of dog food, widely ranging in protein concentration. Twenty-four Labrador retrievers were used and four canned and four kibble diets were selected with crude protein concentrations ranging from 10.1 to 27.5 g/MJ. Crude protein concentration had no influence on the digestibility of Se in either canned or kibble diets, but a lower Se digestibility was observed in canned compared to kibble diets. However, the biological activity of Se, as measured by whole blood glutathione peroxidase, was higher in dogs fed the canned diets than in dogs fed the kibble diets and decreased with increasing crude protein intake. These results indicate that selenium recommendations in dog foods need to take diet type into account.

In the past, most rice study was carried out in irrigated lowland rice and less or no attention was paid to the terraced paddy field system. Study on seasonal rice biomass production and nutrient uptake variation of IR-64 variety cultivated in terraced paddy field system was carried out in Keji Village, Ungaran Sub district during the wet season 2003-04 and dry season 2004. The aim of the study was to evaluate the seasonal variation of rice biomass productions, nutrient concentrations and nutrient uptakes of IR-64. Data were taken from four treatments, namely conventional farmer practice, conventional farmer practices + rice straw, improved technology and improved technology + rice straw. For the conventional farmer practice, only 50 kg of urea ha-1 season-1 was applied. Meanwhile, about 100 kg each of urea, triple super phosphate, and potassium cloride ha-1 season-1 were applied in the improved technology treatments. About 33% of rice straw produced from the previous season was recycled in the treatments of conventional farmer practices + rice straw and improved technology + rice straw. Each treatment was replicated three times and arranged in a Randomised Completely Block Design. Plants were sampled five times, at 45, 60, 75, 90 and 105 days after transplanting. The results indicated that overall production of the improved technology + rice straw treatment was significantly higher than the other treatments both in the wet season 2003-04 and the dry season 2004. Rice grains and rice residues in the dry season were higher than in the wet season, except for the rice straw. However, statistically, there were no significant variations of rice biomass production between the wet season 2003-04 and the dry season 2004. When the rice straw addition was considered, only rice grain production of the dry season was consistently greater than the rice grain production of the wet season. Concentrations of N, P, and K in shoots and roots significantly decreased during rice growth. In contrast to the concentrations, the nutrient uptake increased by the time of rice growth. The highest nutrient concentrations both in the wet and dry season were observed at 45 days after. Contrary to the nutrient concentrations, the highest N, P, and K uptakes were taken place at harvest. Seasonally, nutrient uptakes at harvest in the dry season were higher than in the wet season, but statistical evidences were not consistent. As only rice residues were left in the field, the nutrient amounts taken up by rice straw and rice grains reflect the nutrients removal from the field through harvest. The total nutrients removal ranged between 114 and 119 kg N, 10 and 12 kg P, 133 and 148 kg K ha-1 season-1.

Options to develop tanning industries could be hindered even in the presence of huge leather industry raw materials due to the requirements of high-tech contaminant removal technologies, especially in developing countries. This study was initiated to investigate the efficiency of freeze desalination for Cr(VI) removal using freezers to generate fresh water. Simulated water as well as deionized water to which known concentrations of Cr(VI) spiked into it were studied. The effects of parameters such as initial concentration, freeze duration, ice nucleation, ice volume, and influence of co-occurring ions were evaluated in relation to meltwater. The physicochemical characteristics of the produced meltwater were also evaluated. A high total water recovery of up to 85% V/V of initial water was achieved for the freeze separation rate of 90% in the experimental evaluation. Cr(VI) removal efficiency of up to 80% from simulated tap and 93 to 97% for deionized water spiked with Cr(VI) were found in this batch partial freezing. Freeze desalination was found to be relatively viable desalination technology in terms of quality of water produced, options on the use of cost effective refrigerants and technologies which could have a pertinent importance to save energy consumption of freezers.

The amount of trace elements present in edible bovine tissues is of importance for both animal health and human nutrition. This study presents data on trace element concentrations in semitendinosus and cardiac muscles, livers and kidneys of 60 zebu (Bos indicus) bulls, sampled at Jimma, Ethiopia. From 28 of these bulls, blood samples were also obtained. Deficient levels of copper were found in plasma, livers, kidneys and semitendinosus muscles. Suboptimal selenium concentrations were found in plasma and semitendinosus muscles. Semitendinosus muscles contained high iron concentrations. Trace elements were mainly stored in the liver, except for iron and selenium. Cardiac muscles generally contained higher concentrations of trace elements than semitendinous muscles except for zinc. A strong association was found between liver and kidney concentrations of copper, iron, cobalt and molybdenum. Liver storage was well correlated with storage in semitendinosus muscle for selenium and with cardiac muscle for cobalt and selenium. Plasma concentrations of copper, selenium, cobalt were well related with their respective liver concentrations and for cobalt and selenium, also with cardiac muscle concentrations. The data suggest multiple trace element deficiencies in zebu cattle in South-West Ethiopia, with lowered tissue concentrations as a consequence. Based on the comparison of our data with other literature, trace element concentrations in selected edible tissues of Bos indicus seem quite similar to those in Bos taurus. However, tissue threshold values for deficiency in Bos taurus cattle need to be refined and their applicability for Bos indicus cattle needs to be evaluated.