Uptake and translocation of metals in Spinacia oleracea L. grown on tannery sludge-amended and contaminated soils: effect on lipid peroxidation, morpho-anatomical changes and antioxidants

Toxicity of urban stormwater on Chlorella pyrenoidosa: Implications for reuse safety

Urban stormwater is an alternative water source used to mitigate water resource shortages, and ensuring the safety of stormwater reuse is essential. An in-depth understanding of both individual pollutant concentrations/loads in stormwater and holistic stormwater quality can be used to comprehensively evaluate how safely stormwater can be reused. The toxicity test takes all pollutants present in water samples into account, and the results reflect the integrated effect of these pollutants. In this study, the influence of urban stormwater sourced from different land uses on microalgae (Chlorella pyrenoidosa) and the possible toxicity mechanisms were investigated. The results showed that urban stormwater, particularly residential road stormwater, significantly inhibited microalgal growth. The chlorophyll contents of microalgae exposed to residential road stormwater were relatively lower, while the corresponding values were relatively higher for microalgae exposed to grassland road stormwater. Additionally, the antioxidant-related metabolism of microalgae could be dysregulated due to exposure to urban stormwater. A possible toxicity mechanism is that urban stormwater influences metabolic pathways related to chlorophyll synthesis and further hinders photosynthesis and hence microalgal growth. To resist oxidative stress and maintain regular microalgal cell activities, the ribosome metabolism pathway was upregulated. The research results contribute to elucidating the toxicity effects of urban stormwater and hence provide useful insight for ensuring the safety of stormwater reuse. It is also worth noting that the study outcomes can only represent the influence of land use on stormwater toxicity, while the impacts of other factors (particularly rainfall-runoff characteristics) have not been considered. Therefore, the consideration of all influential factors of stormwater is strongly recommended to generate more robust results in the future and provide more effective guidance for real practices related to stormwater reuse safety.

Diclofenac eco-geno-toxicity in freshwater algae, rotifers and crustaceans

This study assessed the eco-genotoxic impact of diclofenac (DCF) in sentinel species of the freshwater ecosystem. DCF residues are found in freshwater from few ng/L to tens of μg/L due to the inability of conventional wastewater treatment plants to ensure removal efficiency of the drug. An ample body of literature reports on the acute toxicity of DCF in non-target organisms without addressing potential chronic long-term effects on organisms at actual, environmental concentrations. Herein, assessment for acute and chronic toxicity was performed on organisms in vivo exposed to DCF, specifically on the green alga Raphidocelis subcapitata, the rotifer Brachionus calyciflorus and the crustacean Ceriodaphnia dubia. Furthermore, potential DNA damage and expression of antioxidant genes (MnSOD, Cu/ZnSOD and CAT) were evaluated in crustacean neonates. The toxicological risk of DCF was assessed as well as its. GENOTOXIC RISK: The acute toxicity was observed at concentrations far from those of environmental concern. Rotifers and crustaceans were much more chronically sensitive than the algae to DCF, observing besides, the median effect concentrations at tens of μg/L. In crustaceans, DNA damage was noted at units of μg/L, revealing concentrations of environmental concern. The dysregulated activity of SOD and CAT also showed the ability of DCF to provoke oxidative stress. On assessment of environmental risk, the chronic Risk Quotient (RQ) was above the threshold value of 1. Nevertheless, the genotoxic RQ was significantly greater than the chronic RQ, thus, the need of regulatory bodies to acknowledge the genotoxic impact as an environmental risk factor. To our knowledge, this study is the first investigation to perform environmental genotoxic risk assessment of DCF.

Prevalence of urinary symptoms and infections among traditional tannery workers in the Fez city of Morocco: case–control study

Background

Many work activities such as leather tanning include hazards to work. Among these, biological hazards are particularly important and pose a serious problem to human health and environment. The aims of this study were to estimate the prevalence of dysuria and urinary tract infections among tannery workers and to identify their risk factors.

Methods

This observational survey was conducted among 220 tannery workers and 220 age-matched control group from Fez city in Morocco. Reported urinary symptoms, demographic and professional information were obtained by a standardized questionnaire collected from participants and were then compared among the two groups. The logistic regression model was used to explore the interaction between variables with significant association.

Results

The most common symptoms reported by tannery workers and controls were dysuria (36.4% vs. 1.8%, p < 0.001), voiding frequency (15.5% vs. 0.9%, p < 0.001) and incontinence (3.2% vs. 0.5%, p < 0.001). A positive urinary culture was seen in 3.64% of the tannery workers but not in the controls (0%). E-coli was the only species. Multivariate logistic regression showed that exposure to biological hazards increased significantly the odds of dysuria by 6.76 times (CI 1.112–41.78; p = 0.038) but rather, low or normal weight was a protective factor of dysuria (OR 0.53; CI 0.249–0.950; p = 0.035).

Conclusion

Multiple working conditions including exposure to biological hazards may cause an increase in urogenital disorders in the tannery workers. A significantly higher prevalence of urinary symptoms among male workers demand serious attention and further investigation.

Airborne foliar transfer of particular metals in Lactuca sativa L.: translocation, phytotoxicity, and bioaccessibility

The uptake, translocation, and human bioaccessibility of metals originating from atmospheric fine particulate matters (PM) after foliar exposure is not well understood. Lettuce (Lactuca sativa L.) plants were exposed to micronic PbO, CuO, and CdO particulate matters (PMs) by the foliar pathway and mature plants (6 weeks old) were analyzed in terms of: (1) metal accumulation and localization on plant leaf surface, and metal translocation factor (TF) and global enrichment factor (GEF) in the plants; (2) shoot growth, plant dry weight (DW), net photosynthesis (Pn), stomatal conductance (Gs), and fatty acid ratio; (3) metal bioaccessibility in the plants and soil; and (4) the hazard quotient (HQ) associated with consumption of contaminated plants. Substantial levels of metals were observed in the directly exposed edible leaves and newly formed leaves of lettuce, highlighting both the possible metal transfers throughout the plant and the potential for human exposure after plant ingestion. No significant changes were observed in plant biomass after exposure to PbO, CuO, and CdO-PMs. The Gs and fatty acid ratio were increased in leaves after metal exposure. A dilution effect after foliar uptake was suggested which could alleviate metal phytotoxicity to some degree. However, plant shoot growth and Pn were inhibited when the plants are exposed to PbO, and necrosis enriched with Cd was observed on the leaf surface. Gastric bioaccessibility of plant leaves is ranked: Cd > Cu > Pb. Our results highlight a serious health risk of PbO, CuO, and CdO-PMs associated with consumption of vegetables exposed to these metals, even in newly formed leaves in the case of PbO and CdO exposure. Finally, the study highlights the fate and toxicity of metal rich-PMs, especially in the highly populated urban areas which are increasingly cultivated to promote local food.

Heavy metal phyto-accumulation in leafy vegetables irrigated with municipal wastewater and human health risk repercussions

In this study, heavy metal phyto-accumulation potential of selected cultivars of two leafy vegetables on irrigation with municipal wastewater and human health risks were investigated. Municipal wastewater chemistry was recorded significantly different from groundwater control and led to the two-fold high enrichment of soil heavy metal contents (Ni, 19.46; Pb, 23.94; Co, 4.68; Cd, 1.4 in mg/kg, respectively). Interactive effects for phyto-accumulation of most heavy metals were also recorded significant at p < 0.001 in four vegetable cultivars. Heatmap revealed higher accumulation of heavy metals (Fe, Zn, Mn, Cu, Pb, Cr, Co) in spinach cultivars than lettuce cultivars creating elevated health risk index (HRI) and hazard index (HI) values for adults and children. Highest HI was recorded for Lahori palak (adults, 1.42; children, 2.58) and lowest for iceberg (adults, 0.04; children, 0.07). The NPK supplementation improved mineral composition of leafy vegetables within safer human health limits in control treatments. However, in municipal wastewater treatments, NPK fertilization decreased heavy metal uptake and phyto-accumulation in S2 (Lahori palak) than remaining vegetable cultivars leading to reduced health risk values. Because of higher heavy metal phyto-accumulation and health risks, cultivation of spinach cultivars must be discouraged in agro-ecologies receiving municipal wastes, whereas lettuce cultivars should be promoted.

Exposure to aluminum, aluminum + manganese and acid pH triggers different antioxidant responses in gills and liver of Astyanax altiparanae (Teleostei: Characiformes: Characidae) males

Exposure to aluminum (Al) and aluminum + manganese (Mn) can trigger an increase in reactive oxygen species (ROS) and modify the activity of oxidative defense enzymes. This study investigated whether exposure to Al and Al + Mn at acid pH for 24 and 96 h causes oxidative stress evidenced by antioxidants and oxidative damage in the gills and liver of sexually mature Astyanax altiparanae males. The fish were subsequently immersed in metal-free water for 24 and 96 h to see whether they recovered from the effects of these metals. Exposure to an acid pH boosted the activity of gill superoxide dismutase (SOD) at 96 h and the fish did not recover when immersed for the same period in water at neutral pH. Exposure to Al increased glutathione (GSH) levels (24 h) in the gills, returning to control levels during the recovery period, showing the efficiency of the antioxidant system in preventing lipid peroxidation of the gills and liver. Mn did not modify the activity of the enzymes studied, but did trigger late hepatic lipid peroxidation during the recovery period. The group exposed to Al + Mn exhibited several alterations, including increased concentration of GSH, as well as higher GPx and GR activity in the gills. Despite the defensive responses triggered by acute exposure, during the recovery period there were alterations in catalase (96 h) and an increase in hepatic metallothionein (24 h), but this did not prevent hepatic lipid peroxidation. Al and Al + Mn produced different effects, and the timing of enzymatic and non-enzymatic antioxidant defenses also differed.

Toxicity assessment of cobalt ferrite nanoparticles on wheat plants

Cobalt ferrite nanoparticles (NPs) have received increasing attention due to their widespread therapeutic and agricultural applicability. In the environmental field, dry powder- and ferrofluid-suspended cobalt ferrite NPs were found to be useful for removing heavy metals and metalloids from water, while diluted suspensions of cobalt ferrite NP have been promisingly applied in medicine. However, the potential toxicological implications of widespread exposure are still unknown. Since cobalt ferrite NPs are considered residual wastes of environmental or medical applications, plants may serve as a point-of-entry for engineered nanomaterials as a result of consumption of these plants. Thus, the aim of this study was to assess the effects of dry powder and fresh cobalt ferrite NP on wheat plants. Seven-day assays were conducted, using quartz sand as the plant growth substrate. The toxicity end points measured were seed germination, root and shoot lengths, total cobalt (Co) and iron (Fe) accumulation, photosynthetic pigment production, protein (PRT) production, and activities of catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GPX). Increasing total Co and Fe in plant tissues indicated that wheat plants were exposed to cobalt ferrite NP. Seed germination and shoot length were not sufficiently sensitive toxicity end points. The effective concentration (EC₅₀) that diminished root length of plants by 50% was 1963 mg/kg for fresh ferrite NPs and 5023 mg/kg for powder ferrite NP. Hence, fresh ferrite NPs were more toxic than powder NP. Plant stress was indicated by a significant decrease in photosynthetic pigments. CAT, APX, and GPX antioxidant enzymatic activity suggested the generation of reactive oxygen species and oxidative damage induced by cobalt ferrite NP. More studies are thus necessary to determine whether the benefits of using these NPs outweigh the risks.

Growth performance, metal accumulation and biochemical responses of Palak (Beta vulgaris L. var. Allgreen H-1) grown on soil amended with sewage sludge-fly ash mixtures

Agricultural utilization of sewage sludge (SS) and fly ash (FA) has become both, a common practice and an alternative disposal method for these wastes all around the world. The present study was conducted to assess the effect and viability of co-application of SS and FA (SLASH) in four mixing ratios denoted as A [4 (SS): 1(FA)], B [4 (SS): 2 (FA)], C [4 (SS): 3 (FA)] and D [4 (SS): 4(FA)] at three application rates viz. 20, 40 and 60% (w/w) with agricultural soil on biochemical, physiological and growth response of Palak (Beta vulgaris L. var. Allgreen H-1), a commonly used green leafy vegetable. SLASH amendment modified the physico-chemical properties of soil and increased the concentration of heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, Zn) in soil and plant parts however, within the Indian permissible limit except for Cr, Cd and Zn in shoot. Experimental results revealed decrease in morphological and growth parameters such as root and shoot length, leaf area, root, shoot biomass etc. Lipid peroxidation, ascorbic acid, proline and protein content increased however, total chlorophyll and carotenoid content decreased indicating towards heavy metal stress induced biochemical and physiological response in Palak plants. Significant increase in yield was seen in some of the treatments viz. three mixing ratios B, C and D, with maximum increment shown by mixture D at 20 and 40% amendment rate. The results of this study suggest that though SLASH amendment for growing Palak improved the physico-chemical properties of soil amended and also the yield of the plants in some treatments, it may not be a good option due to risk of contamination of heavy metals such as Cr, Cd and Zn showing higher accumulation.

Chromium tolerance, bioaccumulation and localization in plants: An overview

In the current industrial scenario, chromium (Cr) as a metal is of great importance, but poses a major threat to the environment. Phytoremediation provides an environmentally sustainable, ecofriendly, cost effective approach for environmental cleanup of Cr. This review presents the current status of phytoremediation research with particular emphasis on cleanup of Cr contaminated soil and water systems. It gives a detailed account of the work done by different authors on the Cr bioavailability, uptake pathway, toxicity and storage in plants following the phytoextraction mechanism. This paper also describes recent findings related to Cr localization in hyperaccumulator plants. It gives an insight into the processes and mechanisms that allow plants to remove Cr from contaminated sites under varying conditions. These detailed knowledge of changes in plant metabolic pool in response to Cr stress would immensely help understand and improve the phytoextraction process. Further, this review provides a detailed understanding of Cr uptake and detoxification mechanism by plants that can be applied in developing a suitable approach for a better applicability of the process.

Geno- and cytotoxicity induced on Cyprinus carpio by aluminum, iron, mercury and mixture thereof

Metals such as Al, Fe and Hg are used in diverse anthropogenic activities. Their presence in water bodies is due mainly to domestic, agricultural and industrial wastewater discharges and constitutes a hazard for the organisms inhabiting these environments. The present study aimed to evaluate geno- and cytotoxicity induced by Al, Fe, Hg and the mixture of these metals on blood of the common carp Cyprinus carpio. Specimens were exposed to the permissible limits in water for human use and consumption according to the pertinent official Mexican norm [official Mexican norm NOM-127-SSA1-1994] Al (0.2mgL^-1), Fe (0.3mgL^-1), Hg (0.001mgL^-1) and their mixture for 12, 24, 48, 72 and 96h. Biomarkers of genotoxicity (comet assay and micronucleus test) and cytotoxicity (caspase-3 activity and TUNEL assay) were evaluated. Significant increases relative to the control group (p<0.05) were observed in all biomarkers at all exposure times in all test systems; however, damage was greater when the metals were present as a mixture. Furthermore, correlations between metal concentrations and biomarkers of geno- and cytotoxicity were found only at certain exposure times. In conclusion, Al, Fe, Hg and the mixture of these metals induce geno- and cytotoxicity on blood of C. carpio.

Response of leaf and fine roots proteomes of Salix viminalis L. to growth on Cr-rich tannery waste

The tannery industry is a major source of anthropogenic chromium (Cr) contamination due to the large amounts of solid waste produced and its problematic management. The unique composition of tannery waste, usually high concentrations of Cr and other metals as well as organic matter and nutrients, makes it a great risk for soil and water environment but also a possible effective fertilizer for non-food plants that can tolerate metals. The goal of this study was to understand the adaptation mechanism of Salix viminalis to growth on Cr-rich tannery waste from an active landfill. We used a proteomic approach to identify leaf and fine roots proteins altered by tannery waste as compared to control soil conditions. We found no obvious symptoms of oxidative stress in leaves or fine roots. Proteomic results indicated some changes in metabolism, with increases in energy production processes and their greater efficiency for leaves rather than root development. Comparison between S. viminalis and P. × canescens response to tannery waste suggested that S. viminalis is not suitable for remediation of Cr-contaminated areas of a tannery waste landfill site.

Dependence of Guaiacol Peroxidase Activity and Lipid Peroxidation Rate in Drooping Birch (Betula pendula Roth) and Tillet (Tilia cordata Mill) Leaf on Motor Traffic Pollution Intensity

Hormesis and paradoxical effects are frequently found for different plant parameters. These phenomena were also observed for lipid peroxidation (LP) rate at environmental pollution. However, the role of antioxidant enzymes, particularly guaiacol peroxidases (GPX), in a nonmonotonic variation in the LP rate remains insufficiently explored. Therefore, dependence of GPX activity and LP rate in Betula pendula and Tilia cordata leaf on motor traffic pollution intensity was studied. Regression analysis revealed dependences of LP rate and GPX activity on traffic intensity. In B pendula, GPX activity enhanced significantly (up to 2.8 times relatively control) under increased traffic that induced biphasic paradoxical effect for LP rate. In the first phase, LP level increased in comparison with the control, and in the second phase, it was normalized by enhanced GPX activity. In T cordata, dependences of GPX activity and LP rate on traffic pollution were paradoxical effects. However, there was no connection between change of GPX activity and LP rate under middle- and high-level pollution: LP level reduced relatively the control or normalized even if GPX activity was lower than the control. This indicates that in T cordata, other regulatory mechanisms instead of GPX were activated which could control LP rate under middle- and high-level pollution.

Metal contamination in urban street sediment in Pisa (Italy) can affect the production of antioxidant metabolites in Taraxacum officinale Weber

Taraxacum officinale Weber (dandelion) is a very ubiquitous species, and it can grow in urban environments on metal-polluted sediments deposited in the gutters. This study represents a preliminary step to verify the presence of metals in sediments collected in urban streets in Pisa and to assess the alteration in dandelion metabolites in order to understand its adaptation to polluted environments. The soil and sediments were collected at three urban streets and analyzed for total and extractable Cr, Pb, Cu, Ni, and Zn. The total values of Pb and Zn in street sediments exceeded the limits for residential areas of soils. Zn was the most mobile of the metals analyzed. Floating cultivations trials were set up with dandelion seedlings and street sediments. The metals were analyzed in roots and leaves. Antioxidant power, anthocyanins, polyphenols, non-protein thiols (NP-TH) and chlorophylls were measured in dandelion leaves. The first two parameters (anthocyanins and antioxidant power) were higher in the polluted samples compared to the control; chlorophyll content was lower in the treated samples, whereas NP-TH showed no differences. NP-TH groups determined in roots were associated with the root content of Zn and Pb. These results indicate that dandelion can tolerate plant stress by altering its metabolite content.

Genotoxic response and oxidative stress induced by diclofenac, ibuprofen and naproxen in Daphnia magna

CONTEXT

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used pharmaceuticals in Mexico, but there is not proper regulation on the sale, use and disposal. These drugs can enter water bodies by diverse pathways, attaining significant concentrations and inducing damage on hydrobionts.

OBJECTIVE

To evaluate the oxidative stress and consequent damage to genetic material induced by DCF, IBP and NPX on Daphnia magna.

METHODS

The acute toxicity assays were performed to 48-h by nonsteroidal anti-inflammatory drugs evaluated. A sublethal assay were done after 48 h of exposure to DCF, IBP and NPX added to water with the concentration equivalent to the lowest observed adverse effect level (LOAEL), 9.7 mg/L for DCF, 2.9 mg/L for IBP and 0.017 mg/L for NPX. The DNA damage (comet assay) was evaluated at 12, 48 and 96 h. The oxidative biomarkers were evaluated: lipid peroxidation; protein carbonyl content; activity of the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase.

RESULTS

D. magna exposed to DCF, IBP and NPX showed a significant increase (p < 0.05) with respect to controls in LPX. PCC was increased in IBP exposure. SOD and CAT activity were increased by exposure to IBP and NPX. GPX shows a significant increase with respect to control in IBP and DCF exposure and significant decrease by NPX exposure. DNA damage was observed in 48 and 96 h.

DISCUSSION AND CONCLUSION

DCF, IBP and NPX were responsible of alterations in biochemical biomarkers evaluated and DNA damage.

Effect of β-N-methylamino-L-alanine on oxidative stress of liver and kidney in rat

β-N-methylamino-(L)-alanine (L)-BMAA) is a neurotoxic amino acid, found in the majority of cyanbacterial genera tested. Evidence for implication of (L)-BMAA in neurodegenerative disorders, like amyotrophic lateral sclerosis (ALS), relies on bioaccumulation and biomagnification from symbiotic cyanobacteria. The involvement of (L)-BMAA in oxidative stress was demonstrated in several studies in the central nervous system. In the present study, we investigated the effect of (L)-BMAA on the oxidative stress responses of liver and kidney in rats treated by intraperitoneal administration with this amino acid. Oxidative stress was demonstrated by the quantification of lipid peroxidation, the measurement of both catalase and glutathione peroxidase activities, as well as the quantification of glutathione (GSH) levels and the total antioxidant capacity. It was observed that (L)-BMAA caused a significant increase in the degree of lipid peroxidation and catalase activity in both organs. A significant increase in glutathione peroxidase activity was obtained only in liver, whereas glutathione levels were also increased in both organs. The total antioxidant capacity decreased in liver and increased in kidney. These results suggest that the oxidative stress was higher in liver than in kidney, and might be crucial for (L)-BMAA toxicological action.

The relationship between plasma aluminum content, lymphocyte DNA damage, and oxidative status in persons using aluminum containers and utensils daily

OBJECTIVES

The aim of this study was to explore the in vivo effect of the plasma aluminum content on lymphocyte DNA damage, the plasma protein carbonyl (PC) content, and malondialdehyde (MDA) and total antioxidative capacity (TAC) levels in aluminum exposed and non-exposed humans.

DESIGN AND METHODS

Peripheral blood samples were collected from in vivo aluminum exposed and non-exposed humans and the above parameters were measured.

RESULTS

The mean values of lymphocyte DNA damage, plasma MDA, PC levels, and aluminum concentrations were found to be significantly higher in the aluminum exposed group than within the control group (p<0.01). On the other hand, plasma TAC levels were found to be significantly lower in the aluminum exposed group than in the control group (p<0.001). Significant positive correlations were found to exist between lymphocyte DNA damage and the aluminum concentration (r=0.643, p<0.001), DNA damage and MDA (r=0.491, p<0.001), and DNA damage and PC (r=0.548, p<0.01). A negative correlation was found between TAC and DNA damage (r=-0.600 p<0.001) in the aluminum exposed group.

CONCLUSION

Findings from the study revealed that an increased plasma aluminum concentration was associated with increased oxidative stress and increased DNA damage in aluminum exposed humans.

Comparison of two ferns (Adiantum capillus-veneris Linn. and Microsorium punctatum (Linn.) Copel) for their Cr accumulation potential and antioxidant responses

Study was undertaken to compare Cr accumulation in two ferns (Adiantum capillus-veneris Linn. and Microsorium punctatum (Linn.) Copel) and the role of antioxidants were also investigated towards metal tolerance in order to assess the use of ferns in phytomediation/ phytostabilization. Different concentrations (0, 50, 100, 150 microg g(-1) dw) of Cr were added to fern planted in pot containing 1 kg soil. In both the ferns, Cr accumulation increased with increase in metal concentration and maximum accumulation of 800.5 microg g(-1) (fronds) and 1457.4 microg g(-1) (roots) in M. punctatum and 660.8 microg g(-1) (fronds) and 1259.6 microg g(-1) (roots) in A. capillus-veneris was recorded. The increase in the levels of malondialdehyde, antioxidants and antioxidant enzymes (superoxide dismutase, glutathione peroxidase) in A. capillus-veneris was less pronounced than M. punctatum under Cr exposure as compared to their respective controls. In view of less decrease in chlorophyll content and antioxidants along with higher accumulation of Cr in the fronds M. punctatum, is indicative of its higher tolerance towards Cr. However, bioaccumulation factor (concentration of Cr in fronds/concentration of Cr in the soil) of both the ferns was recorded > 1 which qualifies the plants as potential Cr hyperaccumulator and suitable for phytoremediaton.

Aluminum-induced oxidative stress and neurotoxicity in grass carp (Cyprinidae--Ctenopharingodon idella)

Aluminum is used in a large number of anthropogenic processes, leading to aquatic ecosystems pollution. Diverse studies show that in mammals this metal may produce oxidative stress, is neurotoxic, and is involved in the development of neurodegenerative disorders, such as Alzhaimer's and Parkinson's diseases. Nevertheless, there are only few studies with respect to Al-induced neurotoxicity on aquatic fauna, particularly on fishes of economical interest, such as the grass carp (Ctenopharingodon idella). This study evaluates Al-induced toxicity on the grass carp C. idella. Specimens were exposed to the maximum concentration allowed in order to protect aquatic life (0.1 mg L⁻¹), for 12, 24, 48, 72 and 96 h. After the exposure time, lipid peroxidation degree, superoxide dismutase and catalase activity, as well as dopamine, adrenaline and noradrenaline levels were evaluated. Al concentration in organisms and water was also measured, in order to determine the bioconcentration factor. Results show that Al bioconcentrates in grass carp inducing oxidative stress (increment of 300 and 455 percent on lipid peroxidation degree and SOD activity, and decrement of 49 percent on CAT activity) and neurotoxicity (increment of 55 and 155 percent on dopamine and adrenaline levels and decrement of 93 percent on noradrenaline level).

Fractionation and availability of heavy metals in tannery sludge-amended soil and toxicity assessment on the fully-grown Phaseolus vulgaris cultivars

This study was conducted to assess the effect of tannery sludge on the bush bean (Phaseolus vulgaris) cultivars fully-grown on a culture sandy soil, as tannery sludge is valuable to improve soil fertility but long term studies evaluating the effect on fully grown plants are scarce. Tannery sludge amendments (0, 0.77, 1.54, 3.08 and 6.16 g tannery sludge kg(-1) soil) were characterized and the main heavy metals identified (Cr, Mn, Fe, K, and Zn) later on sequentially and singly extracted, for soil fractionation and availability determination, respectively. Metals showed different fractionation and availability patterns, being the most toxic metal (Cr) found to primarily bind to the carbonate fraction in soil, while almost 10% of the total Cr was available for plant uptake. In the green house experiments, bush bean cultivars exposed to increasing tannery sludge amendments were evaluated at different plant stages. Metal accumulation and physiological parameters (chlorophyll, carotenoids, nitrate reductase activity and dry weight) were determined. Toxicity was primarily due to Cr, stimulating or affecting the response of physiological parameters and suppressing seed formation at the highest tannery sludge ratio. Metals were mainly accumulated in the roots of bush beans, diminishing in the upper part of the plants with minimal translocation to seeds, supposing little risk for human consumption. Additionally, important correlations, antagonistic and synergistic relationships were observed between the extracted metals and metal accumulation in plant tissues.

Aluminum-induced oxidative stress in lymphocytes of common carp (Cyprinus carpio)

Several studies of fish have shown that aluminum may induce hypoxia, hypercapnia, metabolic acidosis, and respiratory failure. In lymphocytes, morphologic abnormalities and reduced immune activity have been observed. Nevertheless, there is little data on oxidative stress and such data are essential in order to identify its mechanism of action. The common carp Cyprinus carpio, an omnivorous fish commonly used in commercial aquaculture, has been proposed as a test organism in toxicologic assays due to its economic importance and wide geographic distribution. The aim of this work was to evaluate Al-induced oxidative stress in lymphocytes of the common carp C. carpio. Specimens were exposed to three different concentrations of Al (0.05, 120, and 239 mg/l) in a static exposure system for 96 h. At the end of the exposure period, blood was collected and lymphocytes were separated. Lipid peroxidation, oxidized protein content and the activity of superoxide dismutase, catalase, and glutathione peroxidase were measured. Results show that the tested Al concentrations modified the activity of antioxidant enzymes and elicited higher levels of lipid peroxidation and oxidized proteins. The degree of damage induced was concentration and tissue dependent.

Response of mung bean cultivars to fly ash: growth and yield

Field experiments were conducted to evaluate the effect of fly ash on growth and yield of three locally grown cultivars of an important leguminous plant mung bean (Vigna radiata L.) on soil amended with different concentrations of fly ash. The values of pH, EC, WHC, soil cations, total heavy metals of the soil increased; however, values of BD, NH(4)(+)-N, NO(3)(-)-N, total N, organic carbon (OC), organic matter (OM), available P and cation exchange capacity (CEC) decreased with fly ash incorporation in the soil. Fly ash amendment led to improve the growth performance and various yield attributes. An increase in all the growth parameters was recorded in 10% fly ash amended (FAA) soil for cv M. Jyoti and M. Janpriya, while 5% FAA soil was most suitable for cv M. Jagriti. Yield (gm(-2)) also increased significantly by 40.6% and 33.9% for cv M. Jyoti and M. Janpriya, respectively, in 10% FAA soil and by 29.5% in cv M. Jagriti in 5% FAA soil. The experimental results depict that different cultivars of mung bean demonstrate a marked difference in response to various concentrations of fly ash under field conditions and this may indicate a genetic base for variability.

Diclofenac-enriched artificial sediment induces oxidative stress in Hyalella azteca

Diclofenac is a nonsteroidal anti-inflammatory drug widely used in Mexico where it is sold over the counter. It enters water bodies through municipal and industrial discharges, posing a risk to water systems and aquatic organisms. Diclofenac-enriched artificial sediment was used to evaluate the toxicity of this pharmaceutical on the sentinel species Hyalella azteca, using oxidative stress biomarkers in order to determine if the set of tests used in this study is a suitable early damage biomarker. The median lethal concentration (72-h LC(50)) was determined and oxidative stress was evaluated using lipid peroxidation, protein carbonyl content to evaluate oxidized protein content, and the activity of superoxide dismutase, catalase, and glutathione peroxidase. All biomarkers were significantly altered. Diclofenac induces oxidative stress in H. azteca and the set of tests used (lipid peroxidation, protein carbonyl content, antioxidant enzyme activities) constitutes an adequate early damage biomarker for evaluating the toxicity of this pharmaceutical group in aquatic species.

Oxidative stress induced on Cyprinus carpio by contaminants present in the water and sediment of Madin Reservoir

Madin Reservoir (MR), located in the State of Mexico, is fed mainly by the Rio Tlalnepantla. MR supplies potable water to the municipalities of Naucalpan and Atizapan, and various recreational activities take place in its vicinity, such as sailing and the fishing of diverse species including the common carp Cyprinus carpio. The purpose of this study was to determine the toxic effects of contaminants present in MR water and sediment on C. carpio. Five sampling stations were selected (those considered to have the most problems due to discharges). Water and sediment samples were taken and toxicity studies were performed, including acute toxicity (lethality) and subacute toxicity assays. The biomarkers used in the subacute assays were lipid peroxidation (LPX) and activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in the liver and brain of test organisms. These biomarkers were also evaluated in local carp, i.e. carp with chronic exposure in situ to reservoir contaminants. Results show that contaminants in the water and sediment of the different sampling stations induce oxidative stress, this toxicity being more evident in samples from stations near the entry point of the Rio Tlalnepantla tributary and in local carp. This may be due to high contaminant levels as well as the fact that the physicochemical characteristics of the matrices might favor their bioavailability. Thus, both the water and sediment of this reservoir are contaminated with xenobiotics hazardous to C. carpio, a species consumed by the local human population.

Jatropha curcas: a potential crop for phytoremediation of coal fly ash

A greenhouse pot experiment was conducted to test the heavy metal phytoremediation capacity of Jatropha curcas from fly ash. Both natural accumulation by J. curcas and chemically enhanced phytoextraction was investigated. Plants were grown on FA and FA amended with fertile garden soil, in presence and absence of chemical chelating agent EDTA at 0.1 g kg(-1) and 0.3 g kg(-1) of soil. EDTA enhanced the uptake of all five elements (Fe, Al, Cr, Cu and Mn) tested. Fe and Mn were retained more in roots while Cu, Al and Cr were translocated more to the shoot. Metal accumulation index indicates that the effect of EDTA at 0.3 g kg(-1) was more pronounced than EDTA at 0.1 g kg(-1) in terms of metal accumulation. Biomass was enhanced up to 37% when FA was amended with GS. Heavy metal uptake was enhanced by 117% in root, 62% in stem, 86% in leaves when EDTA was applied at 0.3 g kg(-1) to FA amended with GS. Study suggest that J. curcas has potential of establishing itself on FA when provided with basic plant nutrients and can also accumulate heavy metals many folds from FA without attenuating plant growth.

Role of antioxidants in Cr tolerance of three crop plants: Metal accumulation in seeds

Pot experiments were conducted on three crop plants (Vigna radiata cv. PDM54, V. radiata cv. NM1, Brassica juncea cv. vaibhav) which were grown on six different tannery sludge (TS) amendments. The translocation of Cr to the seeds was found to be higher in B. juncea than the two cultivars of V. radiata, and their levels were below detectable limits in all the three plants grown on lower amendments of tannery sludge (T10 and T25). There was a gradual increase in protein content and antioxidant levels in all the plants grown on lower sludge amendments. However, the levels of all the antioxidants were higher in B. juncea than the two cultivars of V. radiata. The increase in malondialdehyde content of B. juncea was lower than the two cultivars of V. radiata as compared to their respective controls. Overall, the plants of B. juncea have shown better tolerance than both the cultivars of V. radiata.

Iron-induced oxidative stress in a macrophyte: a chemometric approach

Iron-induced oxidative stress in plants of Bacopa monnieri L., a macrophyte with medicinal value, was investigated using the chemometric approach. Cluster analysis (CA) rendered two distinct clusters of roots and shoots. Discriminant analysis (DA) identified discriminating variables (NP-SH and APX) between the root and shoot tissues. Principal component analysis (PCA) results suggested that protein, superoxide dismutase (SOD), ascorbic acid, proline, and Fe uptake are dominant in root tissues, whereas malondialdehyde (MDA), guaiacol peroxidase (POD), cysteine, and non-protein thiol (NP-SH) in shoot of the stress plant. Discriminant partial-least squares (DPLS) results further confirmed that SOD and ascorbic acid contents dominated in root tissues, while NP-SH, cysteine, POD, ascorbate peroxidase (APX), and MDA in shoot. MDA and NP-SH were identified as most pronounced variables in plant during the highest exposure time. The chemometric approach allowed for the interpretation of the induced biochemical changes in plant tissues exposed to iron.

Antioxidant response in sesame plants grown on industrially contaminated soil: effect on oil yield and tolerance to lipid peroxidation

The plants of sesame white (Sesamum indicum L. var. T55) grown on tannery sludge (TS) contaminated soil have shown that Cr level in the seeds was found below detection limits in 10% and 25% TS, however, the levels of Ni, Pb and Cd were found above the recommended limits. In roots, the level of antioxidants increased in the plants grown upto 35% TS at 30d over their respective controls. Total chlorophyll content increased significantly (p<0.5) in the plants (leaves) grown on lower sludge amendments (upto 35% TS at 30d and 25% TS at 60d) over their respective controls. In addition, the oil content increased (35% increase over control) in the plants grown on 35% TS. No significant change was observed in thiobarbituric acid reactive substances (TBARS), a lipid peroxidation index, in the plants (upto 50% TS). The number of trichomes in the leaves of treated plants was found more than control. In lower and upper leaves surfaces, the anterior end of the trichomes was found acute tipped and bent downwards, whereas, the trichome tip was straight and blunt in control. The stomata on upper and lower surfaces of the leaves were found partially or totally closed in the plants grown on 100% TS as compared to control. The toxicity was observed at higher amendments which are evident from the observed morphological changes and decrease in chlorophyll content. This study concludes that it is not advisable to grow the plants on contaminated area, besides its healthy growth.

Comparative growth response of two varieties of Vigna radiata L. (var. PDM 54 and var. NM 1) grown on different tannery sludge applications: effects of treated wastewater and ground water used for irrigation

This study evaluates the possibility of using contaminated soil by treated tannery wastewater and the use of tannery sludge in agriculture. The plants of Vigna radiata var. PDM 54 grown on contaminated soil and irrigated with ground water have not shown the translocation of toxic metal (Cr) in the upper part. The biomass of the plant increased when irrigated with treated tannery wastewater compared to ground water, whereas no significant change was observed in chlorophyll and protein contents. In both the varieties (var. PDM 54 and var. NM 1) of V. radiata grown on tannery sludge amendments, the growth parameters exhibited a pronounced positive growth response up to 35% tannery sludge amendments compared with the plants grown on garden soil. Despite the Cr accumulation at lower amendments, no toxicity symptoms were observed in both the varieties of the plants. Higher amendments affected various growth parameters, NR activity, and carbohydrate content of the plants. The results suggest that the plants of V. radiata (var. PDM 54) may be grown on contaminated soil or lower sludge amendments and irrigated with ground water. No translocation of toxic metal Cr was found in the seeds of the plants grown in up to 25% tannery sludge. However, periodical monitoring is required before the consumption of seeds. Overall, the results showed that plant growth patterns were influenced to some extent by the level of soil contamination and the water used for irrigation.