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Studies on rare earth elements (REEs) of river sediments from Kerala, India indicate that the average total REE (SREE) of clay and silt-sized fractions is much higher than in Post-Archaean average Australian Shale (PAAS). Peak high SREE for the clay fraction is found in the rivers of central Kerala and, for the silt fraction, it is in south and central Kerala. SREE shows a moderate to strong correlation with Mn and P and, no correlation with Al, Fe and Ti in both size fractions. SREE also shows no correlation with heavy metals in the clay fraction but a strong correlation in silt fraction. PAASnormalized REE shows MREE-enrichment in almost all the samples. Further, LREE-enriched and HREEdepleted REE patterns are characteristic of sediments from south and central Kerala, and HREE-enriched or flat REE patterns are characteristic of sediments from north Kerala. Weak positive or weak negative Ce anomalies are characteristic of the sediments. The Eu anomaly is negative in a few silt fractions from south Kerala and positive in all other sediments. Sm/Nd ratios are high in the clay fraction and decrease with increasing SREE for the sediments of central Kerala. REE enrichment and REE patterns are related to the felsic component and heavy mineral content in the sediments of south Kerala, adsorbed REE associated with the weathering products of laterites in the sediments of central Kerala, and the dominance of mafic component in the sediments of north Kerala. The river sediments of central Kerala may serve as a viable REE deposit because of their high REE content, inexpensive mining, easy recovery and extraction of REE. Only 21 out of 41 rivers of Kerala were analysed in this study. Detailed exploration in other rivers may expand and confirm the potential REE deposits and their economic viability. This REE deposit is different from the placer sand deposits on the beaches of south Kerala. [ABSTRACT FROM AUTHOR]

In this study, we analyse the impact of the indiscriminate spilling of spent oil by garages on the surrounding soils. Physico-chemical, biological and heavy metal (HM) profiles of the spent oil-contaminated soils were compared with control samples in Guwahati city, Assam, India. The results revealed that the spent oil-contaminated soils show an increase in the abundance of HMs (varying from 58 to 18,400 mg/kg), total oil and grease (77,000-161,000 mg/kg) and a decrease in bacterial load (68.2-76.2%) and enzymatic activities (18.02-98.4%) when compared with control samples. Site-specific remediation strategies are needed to mitigate this problem. [ABSTRACT FROM AUTHOR]

A systematic study of background radiation in southeast Haryana, India, i.e. the Jhajjar, Sonipat and Rohtak districts, was initiated to establish reliable baseline data on the background radiation level of the region. Worldwide many areas have been found with high background gamma radiation, leading to several types of disorders in human beings. So the present study was carried out as a precautionary step. There are two natural sources of ionizing radiation -- cosmic and terrestrial. Isotopes of heavy elements and their decay products present in the Earth's crust are the major sources of terrestrial radiation. A radiation survey meter was used for the analysis of gamma radiation. In total, 50 locations were chosen for the survey. Gamma radiation showed variation from 82 to 184 nSv/h, with the mean value of 131.64 ± 5.56 nSv/h. An independent t-test at a significance level of 5% was applied for comparison. Annual effective dose and excess lifetime cancer risk were computed to determine the number of cancer cases due to outdoor radiation. [ABSTRACT FROM AUTHOR]

Anthropogenic activities impact the natural environment, leading to the deterioration of its suitability for living organisms and human health. The present study investigated the concentration and distribution of potentially harmful elements Fe, Cr, Cu, Mn, Ni, Pb and Cd in the soil, groundwater and vegetables, and the consequent human health risk effects. Results revealed high content of Cu (mean = 331 mg kg-1) and Zn (mean = 348.4 mg kg-1) in the soils and exceeded permissible limits. Geo-accumulation Index (Igeo) values were high in respect of Cu (Igeo = 3.86, 3.16), and Zn (Igeo = 2.4, 1.6), indicating pollution in the industrial training institute (ITI) and Gular areas in Aligarh respectively. Groundwater from ITI and Gular recorded maximum content of Cr, Cu, Ni, Mn, Zn, Pb and Cd. Ni and Pb contents exceeded the highest permissible limits. Heavy metal pollution index (HPI) with mean HPI = 806.08 indicated serious groundwater contamination in the ITI and Gular areas. Content of heavy metals in vegetables appeared to be under permissible limit with some exception for Ni and Zn. Finally, the assessment of hazard index (HI) indicated that there was no potential risk to human health upon consumption of vegetables, whereas water ingestion posed serious human health hazard (HI = 2.62) in parts of Aligarh. [ABSTRACT FROM AUTHOR]

There is a major knowledge gap and a multifarious problem involving metal chemistry, physical interactions of metals, microbiology, aerobic and anaerobic processes in understanding the precipitation of heavy metals in sewage and polluted water bodies. This study focuses on determining the most feasible metalsalt that can be formed using standard Gibbs free energy change for each possible reaction of all the heavy metals in wastewater. Solubility limits of all possible metal salts are computed. It is shown that even in the short anaerobic stage, any heavy metal will have the propensity to precipitate as sulphides and form insoluble salts, thus rendering the wastewater free from heavy metals. The measured heavy metal concentration in treated wastewater from Bangalore's K-C Valley and Bellandur sewage treatment plants is presented as a validation of the theory. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the suitability of lake sediments of Bengaluru, Karnataka, India, as a nutrient source for agricultural crop production. The sediments were analysed for macro- and micronutrients and toxic heavy metals using standard procedures. The results showed high stocks of N, P and K and low heavy metal concentration in the upper 15 cm depth of the lake sediments, implying their suitability as a nutrient alternative. This will reduce the use of synthetic fertilizers, improve soil health and also increase water storage capacity in the lakes, and thus promote sustainable agricultural production. [ABSTRACT FROM AUTHOR]

Heavy metals are persistent in nature and toxic to all life forms. Increase in industrialization, urbanization and unsafe agriculture practices is constantly adding heavy metals to the environment, and consequently causing heavy metal pollution of water and soil. Considering the negative impacts of heavy metals on the environment, several strategies have been devised to remediate them. However, most of these have their own limitations. Bioremediation of metals by microorganisms is efficient, cost-effective and environmentfriendly method of metal detoxification. Microbes can utilize metal contaminants as their energy source and transform them to less toxic forms. When exposed to metals for a considerable period of time, microorganisms interact with them and become tolerant by developing resistance mechanism against them. Metal-microbe interactions can occur in several ways such as biosorption, bioleaching, biomineralization, bioaccumulation and biotransformation. Study of these interactions is important to understand resistance mechanisms against metals which include barriers, efflux system, sequestration and reduction of metals. These mechanisms are encoded by the resistance genes localized in chromosomes and plasmids. Understanding resistance mechanisms against metals in microorganisms becomes crucial for devising strategies for bioremediation of metals. [ABSTRACT FROM AUTHOR]

Soils and vegetable crops being irrigated with water from six lakes in Bengaluru, India were analysed using ICP-OES for heavy metals and characterized based on the permissible limits of the European Union (EU) and the Indian Standards (IS). Chromium, nickel and lead content in the soils ranged from 89.36 to 145.21, 0.90 to 19.17 and below detection limit to 0.31 mg kg-1 respectively. Among the total soil samples collected, 15%, 22%, 20%, 23%, 15% and 33% of the samples exceeded permissible limits of EU and IS for cadmium under Margondanahalli, Yele Mallappa Shetty, Hoskote, Varthur, Byramangala and Jigani lake respectively. All the crop samples analysed exceeded the EU standards for Cr, 25% for Ni, and none for Cd and Pb. [ABSTRACT FROM AUTHOR]

In the present study, ICP-AES and ICP-MS techniques were used to analyse and validate the content of heavy and trace elements in yellow gypsum samples produced by a chemical process from a solid waste generated at an integrated steel plant. The present study tries to demonstrate that the content of heavy metals like lead, mercury and arsenic in yellow gypsum is less than the toxicity characteristic leaching procedure (TCLP) norms set for a comparable industrial by-product phospho-gypsum. This study also concludes that yellow gypsum contains some elements (copper, boron, etc.) in traces, apart from heavy metals which are beneficial to plants as micronutrients. [ABSTRACT FROM AUTHOR]

Microplastics as environmental pollutants affect surface water and groundwater. Surface water, groundwater and branded drinking water bottles were analysed in and around Chennai, Tamil Nadu, India. The total count of microplastics was found to be 66 particles with fibrous and fragmented shape, colours such as white, blue, green, yellow, pink and black under optical microscope. SEM-EDX-used to study morphology and elemental analysis of microplastics confirmed the presence of heavy metals such as Cr, Ti, Mo, Ba and Ru adhered to their surface. Polyethylene terephthalate and polyamide were confirmed by the presence of functional groups of the polymers by FTIR equipped with attenuated total reflectance. [ABSTRACT FROM AUTHOR]

Heavy metals and organic contaminants are reported in sewage discharged sites. Screening and assessment of their toxic concentration in soils of the discharged sites of major cities in Tamil Nadu, India have been carried out in the present study. The major cities included Coimbatore (Ukkadam; U), Madurai (Avanaiyapuram; A), Tiruchirappalli (Rettamalai; R), Nesapakkam (N) and Koyambedu (K) Chennai Corporation. The total aquaregia-extractable concentrations of cadmium, chromium, lead and nickel were measured and found to be highest in U, followed by A, R, N and K. Their potential bioavailabilities were quantified in the following order: Cd - N > U > K > R > A; Cr - N > A > K > R > U; Pb - N > K > R; U > A; Ni - N > K > R > U > A. Bioavailable Factor was found to be highest for Cd in U (2.9%-83%) followed by Cr in N (1.1%-62.3%) and Ni in (1.70%-52.7%) N. With regard to organic contamination, the major pesticides belonged to 13 organochlorine, 10 organophosphate and 8 synthetic pyrethroids reported below detectable concentration. Among the 16 US EPA priority poly aromatic hydrocarbon (PAHs) only 15 were detected. However, PAHs were found to be less than the permissible concentration for soils (0.3 mg kg-1) in sewage-contaminated sites. The results show that there is potential risk of transfer of heavy metals to higher trophic level of the food chain. [ABSTRACT FROM AUTHOR]

An environmental evaluation of agricultural lands situated close to industrial areas in and around Lucknow city was carried out to determine the effect of co-contamination in the study area. Analysis of soil samples revealed the presence of mercury and cadmium at higher levels than their normal distribution in soil. Apart from heavy metals, the herbicide Butachlor was also detected in most of the soil samples studied. Co-contaminated soils pose a major threat to agricultural ecosystems since the presence of different concentrations of heavy metals may inhibit biodegradation of organic pollutants, which further affects metal bioavailabilty and phytoremediation. [ABSTRACT FROM AUTHOR]

Inductively coupled plasma-mass spectrometry (ICP-MS) is a powerful tool for analysing trace metals in environmental samples, industrial wastes and samples of biogenic nature. In the present study, this technique has been used to analyse the content of heavy metals in trace levels which specifically include elements like lead, cadmium, selenium and arsenic in LD slag fines. LD slag is the waste generated during the Linz-Donawitz steel making process or the basic oxygen furnace process. LD slag fines in the size range 0-6 mm are obtained after the recovery of metallic iron by means of physical separation in waste recycling plants, and are mostly recycled in sinter-making process. The non-metallic portion of LD slag fines is generally used as an aggregate in road construction, in acid mine drainage treatment and as an acidic soil conditioner. All these applications require a thorough analysis of trace and heavy metals as they can leach and penetrate into the soil and potentially contaminate it. The present study addresses this issue by analysing heavy metals in traces levels using ICP-MS. The analysis reveals that most of the heavy and ha- zardous elements are present in very low concentrations in the slag itself when compared with the EPA maximum allowed concentration in the leachate samples. However, the concentration of mercury in LD slag is more than the limit set by EPA in the leachate, and leachability of mercury needs to be studied further. The study also reveals that there are traces of platinum and palladium in the slag, indicating the requirement of future studies to understand their economic recovery. [ABSTRACT FROM AUTHOR]

This paper reveals the magnitude of heavy metal contamination of soil and groundwater in and around an unauthorized e-waste recycling site in Delhi. Though unsafe and unorganized and with the e-waste handling now legally banned in Delhi, the informal sector is still actively involved in dismantling, extracting and disposing of e-waste in certain places on a considerably large scale. The leachate produced by these recycling units contains a large amount of heavy metals which are likely to pollute the groundwater and soil adjoining the recycling sites. This study evaluates the e-waste contamination at such sites by monitoring the potential contaminants at a number of specific monitoring points in Krishna Vihar near Mandoli. The soil and underground water samples are tested for the presence of heavy metals around e-waste recycling and dumping sites using atomic absorption spectrometry. The standard values according to Central Ground Water Board are taken as reference values for water, and standards for agricultural soil in Britain as reference values for soil. The results show that the groundwater and soil in and around these sites have been contaminated by lead, copper, chromium and cadmium to a large extent. [ABSTRACT FROM AUTHOR]

In vitro laboratory experiments were conducted to determine the toxicity (per cent survival and LC50) of essential and non-essential heavy metals (cadmium, copper, nickel, lead and zinc) in four spirotrich ciliates: Euplotes sp., Notohymena sp., Pseudourostyla sp. and Tetmemena sp. isolated from three different freshwater ecosystems in the Delhi region, India. The toxicity of the heavy metals was found to vary among the different ciliates. Copper was most toxic (24 h-LC50 value ranged between 0.125 and 0.74 mg/l) and zinc was least toxic (24 h LC50 value ranged between 46.98 and 144.32 mg/l) to each of the ciliates. Of the four ciliates, Notohymena sp. had the highest tolerance limit to three heavy metals (Cu, Cd and Pb) out of the five tested. This study shows the high potentiality of using freshwater ciliates for monitoring the intensity and potency of ecological damage caused by heavy metals in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

River Gomti receives treated/untreated industrial as well as municipal wastes from various drains of Lucknow city, India. In order to study heavy metal pollution (Cd, As, Pb and Cu) in the river, water and sediment samples were collected from 10 sampling stations along a 9 km stretch in the city of Lucknow. Results revealed that the concentrations of heavy metals in water samples were in the range: As: 0.035-0.061, Cd: 0.016-0.068, Cu: 0.029-0.062 and Pb: 0.031-0.065 mg l-1 whereas in sediments metal concentrations were found to be As: 3.72-14.98, Cd: 1.91-8.39, Cu: 8.97-95.35 and 35.82-90.92 μg g-1. Bioaccumulation of these metals was assessed in four aquatic macrophytes, viz. Pistia stratiotes, Eichhornia crassipes, Polygonum coccineum and Marsilea quadrifolia. Pistia stratiotes and Polygonum coccineum accumulated maximum amount of Pb followed by Cu, Cd and As, whereas in the case of Eichhornia crassipes and Marsilea quadrifolia the relative metal accumulation pattern was found as Cu > Cd > Pb > As and Cu > Pb > Cd > As respectively. The present study suggests that though the concentrations of toxic metals were lower in water, chronic exposure could result in bioaccumulation to a degree many-fold higher than in growing medium. It was also concluded that the water and sediment of the river should be regularly monitored for heavy metal contamination and care should be taken while using river water in agriculture/ aquaculture. [ABSTRACT FROM AUTHOR]

The article presents several science research, as of July 10, 2017. Topics discussed includes presence of heavy metals in the groundwater of peri-urban areas of Ghaziabad, generation of cold plasma using electricity to ionize atmospheric gases to prevent post-harvest groundnut losses, and development of sustainable management strategies for Indian mackerel Rastrelliger kanagurta.

Electronic waste (e-waste) is an emerging source of toxic contaminants in the environment. It is considered to be hazardous as it is known to contain toxic metals, viz. Cr, Ni, Zn, Pb and Hg in huge amounts and organic pollutants, viz. polychlorinated biphenyls, polybrominated diphenyl ethers and tetrabromobisphenol- A. Rapid development and changes in lifestyle have resulted in a huge pile-up of e-waste and its continuous production further makes the situation troublesome. E-waste is usually processed informally for recovery of precious metals. During this process, a large amount of toxic metals, organic compounds and secondary organic pollutants such as polyaromatic hydrocarbons and dioxin enters into the environment. Disposal of raw or processed e-waste in landfills also results in contamination of soil and groundwater through leachate. Considering the present environmental condition along with toxic and persistence nature of pollutants originating from e-waste, their remediation using sustainable methods is highly desirable. This article provides an overview of different bioremediation options used and available for remediation of e-waste-related pollutants. Advantages and limitations of these methods along with their applicability in restoration of contaminated system are also highlighted. [ABSTRACT FROM AUTHOR]

In this communication, accumulated soot from typical Indian share autos and buses has been characterized using FE-SEM coupled with EDS and FTIR spectroscopy for its toxicity level. Analysis reveals the size of spherical-shaped primary particles to be less than 40 nm, which agglomerate to form fractal-like structures. In share autos, average weight percentage of heavy metals such as Cr, Fe, Cu and Pt (except Zn) is higher than that in buses; trace elements include noncarbon elements. FTIR results suggest that share autos contaminate soil of paved and unpaved roadways to a greater extent and at a faster rate compared to buses. [ABSTRACT FROM AUTHOR]

Soil pollution in Guwahati city, Assam, India has become a major concern since the last few decades. To study the impact of automobile and industrial emission, distribution patterns of 16 different polycyclic aromatic hydrocarbons (PAHs) and eight heavy metals were investigated in the soil samples collected from 15 different sites. Higher concentration of total PAHs and heavy metals was found in the industrial areas compared to the high traffic areas. Differences in the pollutants observed between the polluted and nonpolluted sites, endorse that anthropogenic activities are the major cause of soil contamination. [ABSTRACT FROM AUTHOR]

Cr, Pb, Zn, Cd, Ni, Cu, Co and Fe content in the surface sediments was studied at three sites along a 20 km stretch on the Bidyadhari River (situated at the gateway to Indian Sundarban mangrove ecosystem) starting from the sewage outfall zone of the Kolkata metropolis (northern limit of Sundarban) during the dry (March) and wet (August) seasons in the year 2011. The concentration levels of the heavy metals (mg kg-1) were in the following order: Fe (30399 ± 3679) > Cr (68.16 ± 39.28) > Zn (61.33 ± 10.47) > Ni (32.50 ± 4.79) > Cu (27.67 ± 6.59) > Pb (19.69 ± 5.20) > Co (15.23 ± 4.39) > Cd (1.70 ± 0.63). Computation of pollution load index comprising all the heavy metals was found higher during the wet season, mainly due to the enhanced surface run-off led by monsoonal rain. Concentrations of Cr and Co were found higher than the world average in a few cases (especially during wet season); however, computation of pollution indices like contamination factors, enrichment ratio and geoaccumulation index exhibited extremely high Cd contamination in all the sites and during both seasons. [ABSTRACT FROM AUTHOR]

The article offers information on the solid waste management which is one of the biggest environmental challenges in India. It focuses on precipitation infiltrating the solid wastes being disposed on land mixes with the liquids in the crevices of the waste and leach compounds from solid waste. It focuses on the discharge of toxic heavy metals from the leachate into aquatic ecosystems that lead to serious threat due to its toxicity, persistence and bioaccumulation.`

Globally, herbal pharmaceutical industries are among the leading pharmaceutical industries. They generate large volume of wastewater during processing and production, which is highly biodegradable in nature and cannot be discharged into environment as such. Hence efforts are being made to evaluate the toxicity of herbal pharmaceutical effluents using green algae Scenedesmus quadricauda. Physico-chemically treated effluents (PCTEs) as well as biologically treated effluents (BTEs) were observed after the application of S. quadricauda. Also, S. quadricauda showed higher growth rate after the addition of PCTE and BTE. The highest yield of algae was observed in BTE up to 15 days of incubation by synthesis of chlorophyll and cell metabolites, even with 10-100% dilution of effluents. The present study also discusses the evaluation of biotoxicity and recycling on herbal pharmaceutical wastewater along with heavy metal removal. [ABSTRACT FROM AUTHOR]

Plant roots are the main organs through which water, nutrients and pollutants enter the plant body. The roots of soybean plants exhibited absence of root caps and damaged roots when treated with heavy metal cadmium beyond 20 μM. Normally, the roots perceive gravity and grow towards it; but, with heavy metal exposure they become gravi-irresponsive and start growing against the gravity and law of nature. As the graviperception sensors lie in the root cap, roots lose directional growth in the absence of root caps and keep growing in the direction of hilum positioning inside the substratum. So far, no study has reported that heavy metals can cause loss of graviperception in the roots of plants. [ABSTRACT FROM AUTHOR]

Adsorption and desorption studies on different types of adsorbents, including natural materials such as teak tree bark powder, rice husk, natural bentonite, different algae like Ecklonia maxima, Escherichia coli, Ascophyllum nodasum, Rhizopus nigricans, Cladophora fascicularis, goethite and soils of three nuclear power plant and artificial materials such as Fe oxide-coated sand, goethite pretreated with phosphate, dithizonemodified sodium trititanate whisker, modified nanometre sized TiO2, Chromosorb 102 resins and poly(m-phenylenediamine) are summarized. The kinetics, thermodynamics, sorption/desorption mechanism of different metal ions on different adsorbents under different experimental conditions are discussed. It is found that desorbing agent is greatly dependent on the adsorbate used. All the metal ions are desorbed using acids like HCl, HNO3 and H2SO4 in most of the cases, except Cr(VI). EDTA can be used to remove Pb2+ and Zn2+ in addition to acids. Since Cr(VI) is present in anionic form; it can be eliminated from the loaded adsorbents using bases like NaOH, Na2CO3 or NaHCO3. [ABSTRACT FROM AUTHOR]

The levels of heavy metals are measured at different dumpsites with different distances and directions under the jurisdiction of Greater Municipal Corporation of Hyderabad for ascertaining the soil and groundwater quality and forecasting as a part of integrated municipal solid waste (MSW) management study. The datasets indicate a steady decrease in the concentrations of ions and heavy metals in groundwater with distance from the MSW dumpsites. Similar trends are observed for the levels of heavy metals in soil at dump sites around the MSW dumpsite. In this study, we have used both linear and quadratic regression to predict water and soil constituents. As the datasets on the components of solid waste and groundwater are limited, the desired level of forecasting accuracy could not be achieved. However, for some components the results are promising. This study suggests that improvement can be achieved by removing the outliers from the dataset. If the errors are large for a component, it would mean that we need a better way of separation of this component from the waste. [ABSTRACT FROM AUTHOR]

Regular use of compost prepared from municipal solid waste is associated with the entry of heavy metals into the soil, which poses considerable risks to different components of the environment. Total metal content does not generally reflect the availability of metals for the expression of environmental risk because of rapid and strong interactions of the metals with different constituents of the soil. Hence, the present study was conducted to determine screening levels of Cd, Cr, Cu, Ni, Pb and Zn for a susceptible soil by following a widely recommended soil test procedure involving the extraction of these heavy metals with a dilute calcium chloride solution. Separate sets of pot-culture experiments were carried out for each of these heavy metals in graded dose levels (Cd at 0.02-20 mg kg-1, Cr at 0.4-200 mg kg-1, Cu at 1.6-800 mg kg-1, Ni at 0.5- 250 mg kg-1, Pb at 0.4-150 mg kg-1 and Zn at 4.6- 1000 mg kg-1) added to an acidic, light-textured alluvial soil. Soil test screening levels were determined through three different approaches, namely, phytotoxicity, food contamination and soil microbial activity diminution. Except Pb, all other heavy metals significantly reduced the above-ground biomass growth of spinach. Activities of soil enzymes were adversely affected with increasing soil test values of the heavy metals. Screening levels of the heavy metals determined through food contamination and soil microbial activity diminution were much lower than those determined through phytotoxicity. The lowest values of these soil test screening levels of the heavy metals determined by three different approaches were considered to be protective for all target organisms and were found to be: 0.003 mg kg-1 Cd, 0.052 mg kg-1 Cr, 0.637 mg kg-1 Cu, 0.022 mg kg-1 Ni, 0.008 mg kg-1 Pb and 3.800 mg kg-1 Zn. [ABSTRACT FROM AUTHOR]

Two highly lead-resistant bacterial strains designated as M-9 and M-11 were isolated from Zuari estuary of Goa, India, which exhibit resistance up to 0.8 mM and 1.2 mM lead nitrate respectively. These lead-resistant bacterial isolates also tolerate cadmium and mercury as minimum inhibition concentration values for strain M-9 were 0.6 mM and 0.03 mM respectively whereas for strain M-11, the values were 0.6 mM and 0.05 mM respectively. On the basis of biochemical characteristics, 16S rRNA sequence data and fatty acid methyl ester (FAME) profile, these isolates were identified as Pseudomonas stutzeri and Vibrio harveyi respectively. Nested-PCR clearly demonstrated presence of pbrA gene (amplicon size: 750 bp) belonging to P-type ATPase family on chromosomal genome and 5.4 ± 0.7 and 7.9 ± 0.9 fold expression of pbrA gene in Pseudomonas stutzeri strain M-9 and Vibrio harveyi strain M-11 when grown in TMM amended with 0.5 mM lead nitrate revealed efflux mediated lead resistance in both bacterial isolates. PCR amplicons of mdrL gene (1136 bp) and orfA gene (467 bp) also suggested efflux-mediated multiple drug resistance in these lead-resistant isolates. [ABSTRACT FROM AUTHOR]

This study is an attempt to assess the extent of toxic metals, including Pb, Cd, Cr, Mn and As in groundwater and some cereals collected from Shibganj area of Chapai Nawabganj, Rajshahi, Bangladesh. The chemical results of groundwater show that the mean concentrations of Pb, Cd and Mn exceed the values of WHO, USEPA as well as Bangladesh Drinking Water Standards. However, As content is within the permissible limits in terms of Bangladesh Drinking Water Standards, but exceeds the WHO and USEPA values. Cr is in negligible quantity in the examined groundwater samples. Results reveal wide variation in toxic metal content among the three cereal samples. In general, the mean toxic metal concentrations in cereals (rice, wheat and urid bean) are lower than the respective established safe limits for these elements, except for lead concentration in all samples. [ABSTRACT FROM AUTHOR]

We report here the preliminary results of the study using monitored natural attenuation (MNA), referred to as intrinsic remediation, as an in situ treatment method in an abandoned gold mining site in Kolar Gold Fields, Karnataka. The area is called the Kolar schist belt of south India, well-known for its gold deposits which have been mined systematically for over several decades. Distribution of elements, in the form of histograms and correlation diagrams, were prepared to understand the sources of contamination in soils. Natural attenuation observed for some elements were: As (36.6%), Cr (56.6%), Co (50%), Cu (50%), Ni (53.3%), Pb (86.6%), Sr (46.6%) and Zn (50%). The outcome of this study would facilitate identification of safe waste disposal sites besides pointing out the extent of aquifer pollution and prognosis of the migration of pollutants in the plume, and finally support remedial measure. [ABSTRACT FROM AUTHOR]

Chlorophyll a fluorescence measurement has been used as a probe to examine and compare the tolerance of bryophytes against heavy metals stress caused in field trials and under laboratory conditions. The ratio of variable fluorescence (Fv) to the maximal fluorescence (Fm) in dark-adapted leaves termed as 'maximal photochemical efficiency' of PS II (Fv/Fm) was measured in selected bryophytes to study their quantum efficiency. Tolerance potential for lead (Pb) in bryophytes was evaluated statistically by using Dunkun's Multiple Range Test, which indicates that lead-treated moss Grimmia anodon and liverwort Riccardia pinguis exhibited the most physiological damage of PS II. Conversely, minimal changes were observed in Barbula vinealis and Thuidium cymbifolium. Field trials of all the selected bryophytes exhibited moderate changes in the Fv/Fm ratio except G. anodon and R. pinguis. This variation in susceptibility is due to stress caused by metal pollution. Therefore, it is desirable to study the relative tolerance potential of bryophytes as little is known about their susceptibility to metals. Validated tolerant bryophytes species will have multiple applications in studies of biomapping, forest enrichment and carbon gain. [ABSTRACT FROM AUTHOR]

Based on established linkages between ferrimagnetism and heavy metal concentration of anthropogenic particulates, we attempt here to delineate pollutant residing domains and study the role of surface runoff and wind circulations over its redistribution in the Pune Metropolitan Region (PMR) in Maharashtra. A total of 118 samples collected in a ~3 × 3 km grid during pre- and post-monsoon seasons for surface soils, bedrock, dust and rainwaters were analysed for magnetic susceptibility (χlf) and the isothermal remanent magnetization (IRM). The χlf in the soil profiles decrease from bedrock to intermediate soil horizons but notably increase towards top. Spatial variations based on the fundamental rock magnetic parameters (χlf and their frequency dependency (χfd), saturation IRM, demagnetization ratio) and knowledge of the polluting sources show significant anthropogenic loading for the topsoils. The study further reports remarkable postmonsoon changes in all the parameters controlled by surface run-off due to slope variation which appears to be the most effective mechanism of redistribution and dumping the topsoils loaded with anthropogenic particulate matters. Distribution of χfd% further infers wind as another important agent for dispersal of finer ferrimagnetic particulate matters predominantly controlled by the topography amongst other meteorological factors. Additional data for succeeding years would help in modelling the redistribution sensitivity and heavy metal residence effect for the topsoils and sediments in the PMR region. [ABSTRACT FROM AUTHOR]

Heavy metal dispersion in groundwaters of Ankaleshwar Industrial Estate, south Gujarat displays colossal temporal variability in both degree and space. In order to facilitate the quantitative measure for site-specific variations, Normalized Difference Dispersal Index (NDDI) maps for five environmentally sensitive heavy metals (Ni, Zn, Cu, Mn and Pb) were generated by clutching geochemical analyses and GIS-based raster images. Median NDDI value for Ni (0.92) illustrates utmost accretion, whereas that for Zn (-0.58) shows absolute dilution. Widespread enrichment is exhibited by Cu (0.87) and Mn (0.84), while Pb (-0.01) shows inconsequential accretion or attrition. Areas of high inconsistencies were linked to surface-polluting sources by overlaying spatial data on these maps. NDDI mapping is functional for evaluation and comparative assessment of spatio-temporal variations in polymetallic determinants. Frequency distribution and inter-element correlation analyses of the dataset display coherence with the procedure. [ABSTRACT FROM AUTHOR]

The aim of this study is to assess the extent of heavy metal contamination of vegetation due to irrigation with sewage-fed lake water on agricultural land. Samples of water, soil and crop plants have been analysed for seven heavy metals, viz. Fe, Zn, Cu, Ni, Cr, Pb and Cd using atomic absorption spectrophotometry. The results show the presence of some of the heavy metals in rice and vegetables, beyond the limits of Indian standards. Metal transfer factors from soil to vegetation are found significant for Zn, Cu, Pb and Cd. Comparing the results of heavy metals in water, soil and vegetation with their respective natural levels, it is observed that impact of lake water on vegetation was found to be more than the soil. [ABSTRACT FROM AUTHOR]

The article focuses on the groundwater getting contaminated by the tannery effluents containing bleaching agents, heavy metals and other organic material.

The article presents a study regarding the accumulation of heavy metals in fishes and crabs in the Gulf of Cambay, India. It states that high bioaccumulation of metals could be due to anthropogenic activities according to studies on the horizontal distribution patterns of metal in the sediments of the region. It notes that the concentration of toxic metals detected in fish was compared with reported values for other regions in order to measure the degree of contamination in the study area.

The article informs heavy metals contaminate rivers and soils as well as causing harmful effects to living organisms involve humans. Topic include causes damage in kidney, liver, bone and the reproductive system; and presents research with sediments treated with this material can immobilize cadmium and lead metal ions.

The article focuses on mycoremediation, the use of mushrooms or macrofungi for the removal of heavy metal waste which is being considered as an effective alternative as compared to others.

The article offers science news briefs as of April 2016. Topics discussed include use of impurity Pyrophyllite to remove heavy metals ions from water, researchers at Indian Institute of Technology (IIT) have developed a wave rolling model based on wave-form deformation to strengthen thin metal sheets, and scientist at National Chemical Laboratory in Pune, India have developed a technique for the rapid formation of methane hydrate using Tetrahydrofuran (THF).

The article offers information on the floating island or phoomdi in the Loktak Lake of Manipur in North India. It informs that phoomdi provides a variety of bio-products such as wild edible, medicines and fodder. It reveals that the lake has witnessed many ecological disturbances and governing bodies are using dredgers to pull out the biomass affecting the natural habitat. It discusses the use of bio-sorbents like charcoal and rubber for removal of heavy metal from the waste water of lake.

The article discusses the conflict between the modern development and the environment in India. It says that the problem on modern developments is compounded by a carefree use of resources without concern for environmental implications. It indicates that the possible leaching of toxic metals into the soil and water bodies is not much concern to most of the people. It mentions the wasteful practice of the people such as the use of ballpoint pens instead of fountain pens for writing.