Heavy metal accumulation in aquatic animals around the gold mine area of Loei province,Thailand

This research was conducted to assess the water quality and the contamination of heavy metals in water, sediment, fish, and frogs, as well as bioaccumulation factors (BAFs) in fish and frogs around the gold mine area. The water samples were analyzed for water quality (temperature, pH, and dissolved oxygen). The samples were analyzed for heavy metals by inductively coupled plasma optical emission spectrometry. The water quality was within the standard. The concentrations of heavy metals, including As, Cr, Cd, Pb, Ni, Zn, Fe, Mn, and Cu, in water and sediment samples were measured. Three species of fish were collected: Rasbora tornieri, Brachydanio albolineata, and Systomus rubripinnis. The mean heavy metal concentrations of fish were as follows: Fe>Zn>Mn>Cr>Ni>Cu>As>Pb>Cd. The As, Cr, and Pb concentrations in all the fish species exceeded the standard levels. Five species of frogs were collected: Kaloula pulchra, Microhyla heymonsi, Fejervarya limnocharis, Hoplobatrachus rugulosus, and Microhyla pulchra. The mean heavy metal concentrations of frog were as follows: Fe>Cu>Mn>Zn>Cr>Ni>Pb>Cd>As. The Cr, Cd, and Cu concentrations exceeded the standard levels. The BAFs in fish were in order of Cr>Zn>Ni>Cu>Pb>Fe>Cd>As. The BAFs in frogs were Cr>Zn>Ni>Cu>Fe>Pb>Cd>As. The accumulation of heavy metals was higher in the sediment than in the water. Many aquatic organisms take up heavy metals directly from the environment around the gold mine.     

Bioconcentration of Trace Metals in the Tissues of Two Leafy Vegetables Widely Consumed in South West Nigeria

The trace metal levels in the tissues of two popular leafy vegetables Amaranthus caudatus and Corchrus olithorus widely consumed in Nigeria were assessed from a cultivated floodplain receiving effluents from diverse factories in Ibadan. Although the leaves are primarily consumed, the stems are usually used as a feed for farm animals while the roots are disposed by burning when dry or by composting. The objective of this work was to evaluate the level of trace elements in the tissues of these vegetables at harvest time when they become available to the human ecosystem for exposure to the accumulated trace metals, especially the leaves which are cooked and eaten as soup. The results of the mean trace metal levels in the analyses show that the leaves of A. caudatus had the highest bioconcentration in the following order Ba>Mn>Zn>Cu>Pb>Cr>Co>Ni>Cd>U>Sb, stems: Ba>Zn>Mn>Cu>Cr>Pb>Ni>Co>Cd>U>Sb, and roots: Mn>Ba>Zn>Cu>Cr>Pb>Ni>Co>U>Cd>Sb. In C. olithorus, the order was Mn>Ba>Zn>Cu>Pb>Cr>Co>Ni>Cd>Sb>U in the leaves, Mn>Zn>Ba>Pb>Cr>Cu>Co>Ni>U>Cd>Sb in the roots, and Mn>Zn>Ba>Cu>Cr>Pb>Co>Ni>Cd>U>Sb in the stems. The final result of the vegetable samples showed that the trace metal concentration was in the range of Cr (0.8–58.7), Mn (35.0–9,495.9), Co (0.3–33.6), Cu (2.3–60.3), Zn (16.0–538.2), Cd (0.000–40.53), Sb (0.000–0.037), Ba (13.0–1,175.6), Pb (0.9–39.7), and U (0.0–2.2). The bioconcentration factors (BF) for the transfer of trace metals from soil to the tissues showed a higher ease of bioaccumulation when compared to previous studies. The element with the highest BF in the study was Ba (6.45) in the leaves while the least was Co (0.09) in the roots of A. caudatus. The level of bioconcentration of trace metals in the leaves in most of the samples exceeds the recommended levels given by the World Health Organization (WHO) and Federal Environmental Protection Agency (FEPA), Nigeria and therefore constitutes a potential public health risk to the populace who consume these vegetables cultivated in effluent-impacted floodplains.     

The effects of sex and season on the metal levels and proximate composition of red mullet (Mullus barbatus Linnaeus 1758) caught from the Middle Black Sea

The effects of seasonal and sexual differences on the levels of macro, trace element, and toxic metal levels in Mullus barbatus were investigated using the ICP-MS. The quantity relationships of macro elements were found as K>P>Na>Ca>Mg for male, P>K>Na>Ca>Mg in female; the quantity relationships of trace elements were determined as Fe>Zn>Mn>Mo>Se>Cu>Ni>Co in male, Fe>Zn>Mn>Se>Cu>Ni>Mo>Co in female; and the quantity relationship of toxic elements were found as As>Pb>Cd in both male and female. Macro, trace, and toxic metal levels showed no significant differences (p > .05) in terms of sexuality, but demonstrated seasonal differences (p > .05). Overall, the highest level of macro elements was determined in the autumn, while the high level of trace elements was measured in the winter. The As, Cd, and Pb levels in the muscle tissue of red mullet fish were higher than acceptable limits. However, when the Estimated Daily Intake (EDI) and Estimated Weekly Intake (EWI) of both toxic metals are considered, they appear to be below acceptable limits. As a result, it was determined that the red mullet had been contaminated with toxic metals (Cd and Pb) but their levels according to EDI and EWI were below the limit.     

Seasonal accumulation of metals by red alga Gracilaria verrucosa (Huds.) Papens. from Thermaikos Gulf, Greece

Concentrations of Fe, Pb, Cu, Zn and Cd were determined during one season in the red alga Gracilaria verrucosa, sediment and seawater from the Thermaikos Gulf, Greece. This region has been subject to change due to increases in industrial and domestic activities. The relative abundance of metals in G. verrucosa and seawater decreased in the order: Fe>Zn>Pb>Cu>Cd and in the sediment: Pb>Fe>Zn>Cu>Cd. Cadmium concentration in the alga correlated positively with that in seawater. There was positive correlation between Fe concentrations in the alga and those of the Zn and Cu. The concentrations of metals in the alga showed no significant differences between the stations. Lead, Zn and Cu concentrations in the alga were slightly higher at Biamyl, whereas Cd was higher at Perea and Fe at Nea Krini. Seasonal variation of metal concentrations in the alga was significant for Cd and Fe. Copper and Fe increased from winter to summer, whereas Cd was the opposite. Zinc concentrations were minimum and Pb concentrations were maximum during spring. These variations are discussed in relation to tissue age, life cycle, ambient concentrations of metals and other environmental conditions. Cd and Pb concentrations inG. verrucosa in the Thermaikos Gulf were higher and those of Cu and Zn were lower than in other species of the genus. This revised version was published online in August 2006 with corrections to the Cover Date.     

Heavy metals contamination and human health risk assessment in soils of an industrial area,Bandar Abbas – South Central Iran

The purpose of this study was to determine the contamination level, distribution, health risk and potential sources of Cr, Cd, Pb, Zn, Cu, Ni and As in 66 topsoil samples from industrial areas in Bandar Abbas County. The geoaccumulation index, pollution index and pollution load index were calculated to assess the pollution level in the industrial soils. The hazard index and carcinogenic risk were used to assess human health risk of heavy metals. Results showed that the contamination levels of heavy metals were in the descending order of Cu> Cd> Pb> Zn> As> Ni> Cr. Moreover, based on principal component analysis, Cd, Zn, Cu, and Pb originated mainly from anthropogenic sources, including power plants, oil and gas refinery, steel and zinc production factories and municipal waste landfills. For non-carcinogenic effects, hazard index of studied metals decreased in the order of Cr> As> Cd> Pb> Ni > Cu> Zn. Arsenic, chromium and cadmium were regarded as the priority pollutants. Carcinogenic risks due to Cd and As in suburban soils were within tolerable risk to human health; however, children faced more health risk in their daily life than adults via their unconscious ingestion and dermal contact pathway.     

Comparison of Source Identification of Metals in Road-Dust and Soil

Source identification of toxic metals is very critical for pollution prevention and human health protection. Many studies only use either road dust metal data or soil metal data to evaluate metal contamination and identify pollution sources, and this may lead to the exclusion of some important information. In this study, the differences of metal spatial distribution and source identification between road dust and associated soil in an industrial area were investigated.

Results indicate the metal concentrations in road dust were generally higher than those in soil. Based on the average concentrations, the order for dust metal concentrations was Fe>>Zn>>Pb>Cu>Cr>Ni. The order for soil metal concentrations was slightly different, namely Fe>>Zn>>Cu～Pb>Ni>Cr. The spatial distributions of metals in the road dust were very different from those in the soil, except for Fe. The GIS results indicate that elevated levels of Fe, Zn, and Pb were present in road dust near a steel plant. High concentrations of Cu, Cr, and Ni appeared at a road intersection. Elevated metal concentrations of Fe, Zn, Pb, Cu, and Cr were present in soil around the steel plant. A coal-fired power plant did not seem to be a significant metal source in this study. Significant correlations for dust metals imply that these were well mixed in the study area. The metal sources identified by PCA with soil metal data were obviously different from those identified with road dust metal data. When road dust metal data were used, the changes of PCA analyzed areas slightly influenced the source identification. The PCA results were obviously influenced by changes of analyzed areas when soil metal data were used.     

Distribution of heavy metals in surface sediments of the Bacochibampo Bay,Sonora, Mexico

Abstract

The aim of this study was to determine the levels of heavy metals (Al, Cd, Cr, Cu, Fe, Mn and Pb) in the geochemical fractions of the coastal surface sediments from the Bacochibampo Bay in Sonora, Mexico. Two surveys were conducted (March and September) during 2004, at eight sampling stations inside the bay, and in three natural effluents discharged into this bay. The extraction of metals was carried out using a microwave oven method and the quantification was done by atomic absorption spectro-photometry. The highest detected concentration of total heavy metals in sediments was: Fe>Al>Mn>Pb>Cr>Cu>Cd, with the following concentration values: Fe (1.72%), Al (1.03%), Mn (416.31 mg kg^?1), Pb (11.73 mg kg^?1), Cr (11.41 mg kg^–1), Cu (6.78 mg kg^–1) and Cd (1.33 mg kg^–1). The levels of total heavy metals (Al, Cr, Cu, Fe, Mn and Pb) were much less than the lowest observable effect level (LEL) which indicates that the sediments were not from polluted areas and that the origin of the metals was due to natural conditions. However, concentrations of Cd were much higher than the low effect level (LEL), over 40% of metal was detected in the exchangeable fraction and carbonates. The normalisation study showed a high degree of enrichment of Cd in all the sampling stations in the Bacochibampo Bay (samples EF 34–87) and in the natural flows that discharge into this bay (samples EF 22–35%), which exceeds by several orders of magnitude the value of sample EF 1, which indicates that Cd is anthropogenically induced. Based on these results, it is important that precautionary measures are established, since the deposited Cd in these fractions may be potentially toxic, due to the physicochemical changes that occur in the environment. Thus, future studies will focus on identifying problems involved with Cd bioaccumulation in different trophic levels.     

Ecological risk assessment of heavy metal contamination in mangrove habitats,using biochemical markers and pollution indices: A case study of Avicennia marina L. in the Rabigh lagoon,Red Sea

Contamination of mangrove ecosystems, including those of the Red Sea area, has caused serious concern globally. Spatial distribution of heavy metals and their bioaccumulation in one of the common mangrove plants of Saudi Arabia, Avicennia marina L., was evaluated in 8 stations at the Rabigh lagoon to assess the ecological risks due to heavy metal contamination. Among all the heavy metals, Fe concentration was recorded highest (8939.38 ± 312.63 mg/kg) at station S4. Contamination factor (CF) values for all heavy metals determined in this study were recorded in ascending order as Cu < Cr < Mn < Zn < Fe < Ni < Pb < Cd, with the pollution load index pattern recorded in descending order as S6 > S4 > S3 > S5 > S7 > S1 > S8 > S2. Bio-concentration factor (BCF) was <1 for all the heavy metals and there was a positive correlation between the antioxidants and lead (Pb), which can be a result of the ability of A. marina to exclude or detoxify this metal by its mechanism of exclusion or detoxification. A significant correlation existed between the heavy metals concentration in sediment and A. marina leaves at one combination or the other, except for Cu and Cd, which do not correlate with any other metal concentration. The information provided in the present study can be used in the monitoring and measurement of heavy metal pollution in marine ecosystems or other aquatic environments, to prevent several ecological risks to the mangrove ecosystem.     

Impact of treated municipal wastewater irrigation on turnip (Brassica rapa)

The effect of treated municipal wastewater on the roots and the leaves of turnip was studied to compare the 50% and 100% wastewater of 34 ml/d Sewage Treatment Plant (STP) with different doses of potassic fertilizers. Turnip (Brassica rapa) was used as a test plant. A pot experiment was conducted, using a factorial randomized block design to investigate the growth and translocation of heavy metals to the leaves and the roots of turnip. The concentration of heavy metal in wastewater used for irrigation was within the limits. However, the concentration in the plant parts showed a significant rise due to continuous use of wastewater. The concentration of heavy metals in leaves and roots was at excessive levels at 40 and 55 days after sowing (DAS), while at 70 DAS, metal concentration was comparatively low. The range of heavy metals in wastewater irrigated plants was Cd = 1–16.3, Ni = 0–136, Fe = 263–1197, Cu = 0–18, Mn = 37–125, and Zn = 42–141 mg/kg. Concentration of heavy metals in plants was found in the order of Fe>Zn>Ni>Mn>Cu>Cd.     

Distribution of heavy metals and their chemical speciation in sediments from the Abelardo L. Rodríguez Dam,Sonora, México

Abstract

The purpose of this study was to investigate the distribution of total and bioavailable metals (Cd, Cu, Cr, Fe, Mn, Pb and Zn) in sediments of the Abelardo L. Rodríguez (ALR) dam located in the eastern part of the city of Hermosillo, Sonora, Mexico. Seventy two sediment samples were collected in 2009 during four sampling campaigns in February (spring), May (summer), September (end of summer) and December (winter) in five different areas within the dam surface (Zones I, II, III, IV and V), including the Gate Station. Determination of heavy metals was carried out by flame atomic absorption spectrophotometry (FAAS). The results indicate high levels of total heavy metals in the following order: Fe>Mn>Zn>Pb>Cu>Cr>Cd. This is indicative of the impact of human activities located in areas surrounding the reservoir, specifically urban and industrial. The distribution and state of accumulation of trace metals in the sediment is largely dominated by the residual and Fe/Mn oxides geochemical phases. Fraction I (exchangeable) also presented high concentrations of metals (Cu, Fe, Mn and Zn). From enrichment factor analysis, the study area is prevalently enriched in Cd, Cu and Pb in Zones I, II, III, IV and Gate Station. This indicates that the sediments are impacted by anthropogenic activities such as downloads, domestic and industrial wastewater. Geoaccumulation index (Igeo) indicates that Zones I, II, III, IV and V (including Gate Station) do not show contamination by Cr, Fe, Mn and Zn. However, there is a moderate to heavy contamination by Cd, Cu and Pb (Igeo: 2–4) in all areas of study. The comparison between the results obtained with the sediment quality criteria (LEL and SEL), indicate that Zones I, II, III, IV, V and Gate Station, are contaminated with Cd, Cu and Pb, and severely contaminated by Fe.

The elevated levels of heavy metals detected in the sediment of the ALR Dam require special attention, since in the exchangeable fraction, the metals are specifically adsorbed on the sediment and can be released when the ionic composition of water changes. However, additional studies are required in this reservoir on the chemistry and toxicology of metals for a full assessment of potential risks posed to biota and man.     

Geochemical distribution of heavy metals in sediments from sewage fed fish ponds from Kolkata Wetlands,India

Abstract

Kolkata wetlands are the largest sewage fed wetlands in the world. They have been used for aquaculture since 1960. Geochemical distribution of heavy metals (Cr, Cu, Mn, Fe, Zn, Pb, Ni and Al) has been studied in surface sediments using single and sequential extractions techniques. The metal concentrations in sediments were in the following order: Fe>Al> Mn>Zn>Cu> Pb>Cr> Ni, and the average concentrations were 29 μg g^?1, 54 μg g^?1, 328 μg g^?1, 32747 μg g^?1, 169 μg g^?1, 38 μg g^?1, 25 μg g^?1 and 23371 μg g^?1 dry weights for Cr, Cu, Mn, Fe, Zn, Pb, Ni and Al, respectively. Water-soluble percentages of the trace elements are quite low (<0.01–3.75%) but in the presence of chelating agents in the sediments increase the bioavailability of trace elements (2–58%). About 40% of trace elements are in the stable form as a residual fraction of the sediment and more than 50% (nonresidual fraction) metal contamination of the Kolkata wetland sediments were from anthropogenic inputs. The contamination risks of Cr, Mn, Zn, Pb, and Ni are high as their potential availabilities are 70.96%, 58.01%, 63.13%, 55.62%, and 52.15% respectively. The mean concentration of most of the heavy metals in sediments does not exceed the recommended reference values. Zinc and lead concentrations were greater than background level and Interim Sediment Quality Guidelines but lower than Probable Effect Level. Therefore a regular program for monitoring the distribution of heavy metals in water, sediments and biota should be imposed on sewage fed fish ponds of the Kolkata wetland ecosystem.     

Sequential extraction of trace metals and particle size distribution studies of Kainji Lake sediment,Nigeria

Abstract

Sequential extraction was carried out to determine the concentrations of some trace metals (Mn, Cu, Fe, Pb and Cd) in the Kainji lake sediments from seven different locations in four fractions: exchangeable, bound to iron and manganese oxide, bound to organic matters and residual. This was to undertaken to assess the environmental fate of these trace metals. The BCR technique, a modified form of the Tessier method of sequential extraction was used.

The proportion of the mean metal concentrations of the bioavailable metals follows the order Fe>Cu>Pb>Mn>Cd. Generally, Fe was most abundant metal in the sediment and about 40% was found in its bioavailable form. Although Cd contributed least to the bioavailable content, a greater percentage (~60%) was found in the bioavailable fraction. This suggests that Cd is highly mobile and, since it is known to be toxic, its concentration in the bioavailable form constitutes an environmental threat.

The contribution of metals bound to organic matter was found to be high and of the same magnitude as those bound to oxides and constitutes about 70% of the non-bioavailable metal contents. The petrological analysis of the sediments revealed that the sediments were predominantly quartz and rock clays with percussion marks and indentations.     

Trace metal fractionation in water and sediments of an urban river stretch

Abstract

In this study, the fractionation and ecotoxic potential of Cr, Ni, Cu and Pb in water and sediments of the river Yamuna (Delhi stretch) is presented. The river water is used for various purposes such as irrigation, industrial, domestic and drinking. The investigations suggest that the availability of metals in water follows the sequence Ni>Cr>Pb>Cu whereas a different pattern (Pb>Cu>Ni>Cr) is observed in sediments. Statistically significant spatial variations are indicated by two-way ANOVA in different geochemical forms of the metals and physicochemical parameters of water and sediments of the river Yamuna. Principal component analysis (PCA) suggests a similar source for all four metals probably from the sewage from municipal drains. PCA also indicates some independent sources of Cu and Pb. The hot spots were identified using hierarchical cluster analysis considering bioavailable forms of the metals in water and sediments as objects and the sampling sites as variables. Risk assessment code analysis indicates that metals generally pose medium to high risk at different sites. However, at a few locations either Ni or Pb cross the level of very high ecological risk.     

Field accumulation risks of heavy metals in soil and vegetable crop irrigated with sewage water in western region of Saudi Arabia

Wastewater irrigated fields can cause potential contamination with heavy metals to soil and groundwater, thus pose a threat to human beings . The current study was designed to investigate the potential human health risks associated with the consumption of okra vegetable crop contaminated with toxic heavy metals. The crop was grown on a soil irrigated with treated wastewater in the western region of Saudi Arabia during 2010 and 2011. The monitored heavy metals included Cd, Cr, Cu, Pb and Zn for their bioaccumulation factors to provide baseline data regarding environmental safety and the suitability of sewage irrigation in the future. The pollution load index (PLI), enrichment factor (EF) and contamination factor (CF) of these metals were calculated. The pollution load index of the studied soils indicated their level of metal contamination. The concentrations of Ni, Pb, Cd and Cr in the edible portions were above the safe limit in 90%, 28%, 83% and 63% of the samples, respectively. The heavy metals in the edible portions were as follows: Cr > Zn > Ni > Cd > Mn > Pb > Cu > Fe. The Health Risk Index (HRI) was >1 indicating a potential health risk. The EF values designated an enhanced bio-contamination compared to other reports from Saudi Arabia and other countries around the world. The results indicated a potential pathway of human exposure to slow poisoning by heavy metals due to the indirect utilization of vegetables grown on heavy metal-contaminated soil that was irrigated by contaminated water sources. The okra tested was not safe for human use, especially for direct consumption by human beings. The irrigation source was identified as the source of the soil pollution in this study.     

Quantitative speciation of heavy metals in soil and crops of agricultural fields of Islamabad,Pakistan

Abstract

Two root crops: carrot (Daucus carota) and spring onion (Allium fistulosum) and soil samples were selected from the agricultural fields located near Islamabad, Pakistan to determine their elemental content. Field soil speciation of the two crops was also carried out to analyse the correlation of the elements in field crop and soil. Concentrations of selected elements were evaluated in the leaf, stem, root and flowering part of the crops using flame atomic absorption spectrophotometry. The results showed that elements are mostly concentrated in soil rather than crop parts following the sequence Zn>Cu>Pb>Ni>Cr>Cd. Furthermore, soil speciation showed that Ni and Cr are more prevalent in the Fe–Mn oxide fraction, Zn and Cd as the carbonate bound fraction and Cu is found in the organic bound form. However, concentrations of Pb are similar across the carbonate, Fe–Mn oxide and organic bound fractions. The highest average concentration of Zn is found as the carbonate bound fraction (2.09 ± 0.005 mg kg^?1) and Cu as the organic bound (1.51 ± 0.029 mg kg^?1) in soil samples taken from the agricultural field of Daucus carota.     

Heavy metals uptake by vegetables growing in sewage irrigated soil: relationship with heavy metal fractionation in soil

Abstract

Concentrations of the heavy metals Cd, Ni, Cr, Zn, Mn, Co and Cu in soils and vegetable samples (i.e. green chili and gourd) taken from six vegetable fields in the vicinity of Lahore, Pakistan were measured. These soils have been irrigated for a long time with untreated sewage effluents. A control site was selected that has history of fresh canal water irrigation. The sequential extraction procedure developed by Tessier was adopted to demarcate five metal fractions: exchangeable, acid soluble, reducible, oxidizable and residual. The extractants and digests were analysed by atomic absorption spectrometry. The fractionation procedure showed that all the metals were dominant (>50%) in the residual phase in control as well as in waste waster irrigated soils. The concentrations of all the metals in edible parts of the vegetables collected from wastewater irrigated soils, were above critical levels. The total metal concentrations in wastewater irrigated soils followed the order Mn> Co> Zn> Cr> Ni> Cu> Cd, while in control soils the ord er was Mn> Zn> Ni> Co> Cr> Cu> Cd. In order to understand the uptake of metals from soil to vegetables, correlation analyses were performed between metal concentrations in different fractions of soil and their concentrations in vegetables. Correlation analysis was performed at 95% and 99% confidence level. The meaningful significant negative correlation was observed between Cd_F5–Cd_chili,Cr_Total–Cr_gourd,Mn_F5–Mn_Chili,Gourd, Co_F5, _Total–Co_chili, Cu_Total–Cu_Chili which indicate the non availability of total content and residual fraction to studied vegetables. The positive correlation was observed between Cd_Fl-Cd_ChiU, Cd_Fl–Cd_gourd, Ni_{Fi, F3}–Ni_Gourd, Cr_{Fi, F3}, _F4–Cr_ChiU, Cr_F2–Cr_Gourd, Zn_{Fi, F2}–Zn_Gourd, Mn_F3–Mn_Chili, Mn_Fi–Mn_Gourd, Co_F2–Co_Chili, Cu_Fi–Cu_Chili. The positive correlation, especially for the first (exchangeable) second (acid soluble) and for the third (reducible) extraction steps, was obtained which indicate the bioavailability of these metal fractions to plant.     

Water quality index,Labeo rohita,and Eichhornia crassipes: Suitable bio-indicators of river water pollution

The present study investigated the water quality index (WQI) of the Kshipra river at Dewas, Madhya Pradesh, India, using native fish Labeo rohita, and plant Eichhornia crassipes. The temperature, pH, dissolved oxygen, alkalinity, turbidity, and dissolved solids were found to be within the prescribed limits. However, heavy metals concentration exceeded the limit except for Cu and Zn. Their occurrence in river water was as follows: Ni > Fe > Cd > Cr > Mn > Zn > Cu. Among these heavy metals, Cd was found to be highly bioavailable, whereas Zn was the least bioavailable metal. Based on WQI, the water was found to be unfit for drinking, and the high WQI value was due to the presence of Cr and Cd. In fish tissues (muscle, liver, gut, gills, and kidney), the highest and lowest metal pollution index was found in gills (45.03) and kidneys (12.21), respectively. Bioaccumulation of these metals resulted in significant depletion of energy reserves (protein, glucose, and glycogen) and also altered hematological parameters. Moreover, liver function tests showed hepatic damage in the exposed fish. In-plant, both the bioaccumulation and mobility factor exceeded 1 for all these metals. On the other hand, the translocation factor was found to be beyond 1 for Fe, Ni, and Zn. These high values make this plant fit for phytoextraction of Mn, Fe, Cu, Zn, and Cd and phytostabilization of Cr in water. Moreover, consumption of L. rohita from the Kshipra River does not pose a non-cancer risk as the target hazard quotient was below 1, but it may pose cancer risk because of the presence of Cr in the range of 1.402 × 10^?3 to 1.599 × 10^?3.     

Metal phytoremediation potential of naturally growing plants on fly ash dumpsite of Patratu thermal power station,Jharkhand, India

Three naturally growing plants Ipomoea carnea, Lantana camara, and Solanum surattense were found in fly ash dumpsite of Patratu thermal power station, Jharkhand, India. They were assessed for their metal uptake potential. The fly ash was slightly alkaline with very less nitrogen and organic carbon but enriched with phosphorus and heavy metals. Lantana camara and Ipomoea carnea showed good translocation from root to shoot for most of the metals except Mn and Pb. The order of metal accumulation in stem of both the plants were Fe(205mg/kg)>Mn(65mg/kg)>Cu(22.35mg/kg)>Pb(6.6mg/kg)>Cr(3.05mg/kg)>Ni(1 mg/kg)>Cd(0.5 mg/kg) and Fe(741 mg/kg)>Mn(154.05 mg/kg)>Cu(20.75 mg/kg)>Pb(6.75 mg/kg)>Ni(4.0 mg/kg)>Cr(3.3mg/kg)>Cd(0.05mg/kg), respectively. But Solanum surattense accumulated most of the metals in roots. The order was in the following order, Mn (382.2mg/kg) >Fe (264.1mg/kg) > Cu (25.35mg/kg) >Pb (5.95 mg/kg) > Ni (1.9 mg/kg) > Cr (1.8mg/kg) > Cd (0.55 mg/kg). The order of Bioconcentration factor (BCF) in root and shoot followed almost the same order as, Mn>Fe>Ni>Pb>Cu>Cr≈ Cd in all the three species. ANOVA showed significant variation in metal accumulation by root and stem between the species. Finally, it can be concluded that Solanum surattense can be used as phytostabilizer and other two species as phytoextractor of metal for fly ash dumpsite reclamation.     

Bioaccumulation of heavy metals and their toxicity assessment in Mystus species

This study was conducted on two native fish species namely Mystus vittatus and Mystus tengara inhabiting challenging environment of Yamuna River. The heavy metals concentrations in the river water were found to be as follows: Fe > Mn > Zn > Cu > Ni > Cr > Cd, all above the Bureau of Indian Standards (BIS) and World Health Organization (WHO) guidelines. The high metal pollution index in gill, liver, and kidney of M. vittatus was recorded compared to M. tengara. The pathology caused by the accumulation of heavy metals resulted significantly (p < 0.05) higher enzyme activities of alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatinine kinase (CK) in M. tengara as compared to M. vittatus. However, albumin: globulin ratio was found to be below 0.8 in both fishes. Higher total leukocyte (TLC) (48.5 × 10³/mm³), lymphocytes (40%), respiratory burst activity (1.9), and nitric oxide synthase (NOS) activity (13.11 U/L) in M. vittatus reflect high immune response. In addition, chromosomal breakage study showed significantly (p < 0.05) low micronuclei frequency, lobed nuclei, and kidney-shaped nuclei (KSN) in M. vittatus. These results indicate that under the same challenging conditions M. vittatus have more capability of resistance and its continuous survival points towards its suitability to serve as a bioindicator than M. tengara.     

Biosorption and growth inhibition of wetland plants in water contaminated with a mixture of arsenic and heavy metals

The potential of wetland plants as an onsite biosorbent and a biomonitor for combined pollution of arsenic and four heavy metals from non‐point sources was investigated in this study. Ceratophyllum demersum, Hydrilla verticillata, Hydrocharis dubia, and Salvinia natans were exposed to a water containing mixture of As, Cr, Cu, Pb, and Zn. Growth inhibition and biosorption potential of the wetland plants in artificially contaminated conditions were studied. These contaminants significantly reduced the growth of the plants. The tested wetland plants accumulated appreciable amounts of the contaminants in the following order: Pb>Cr>Cu>Zn>As. H. verticillata showed distinct visual change and a high biosorption factor (BSF) rank for As and heavy metals among the plants used in the study. As an unspecific collector of contaminants, it might be useful as a biomonitor and biosorbent in the As and heavy metal‐contaminated aquatic system.