Evaluation of genotoxic potential of industrial waste contaminated soil extracts of Amritsar, India

The rapid increase in population together with unplanned disposal of effluents from various industries has resulted in accumulation of various heavy metals like As, Cr, Cu, Hg, Ni, Pb and Zn in soil ecosystem which ultimately causes DNA damage in living systems. Considering this, the present study was designed to evaluate the content of various heavy metals (Cu, Cr, Co, Hg, Mn, Ni, Zn) and genotoxicity/mutagenicity of soil samples collected from the outskirts of two industries viz. zinc coating industry (SI) and copper sulphate manufacturing industry (SII) employing Allium root anaphase aberration assay (A/RAAA) and Ames assay. The physicochemical parameters like bulk density, water holding capacity, moisture content, pH, nitrates, phosphates and potassium were also estimated. It was observed that SI sample contained Ni (6.86 mg g-1), Zn (6.53 mg g-1), Co (5.05 mg g-1) and Cr (4.49 mg g-1), while SII contained Cu (32.86 mg g-1), Ni (9.66 mg g-1), Co (6.85 mg g-1) and Zn (5.41 mg g-1). In A/RAA assay, the percentage of cells with anaphase aberrations ranged from 3.63 to 10.67 and 0.38 to 4.83% for samples SI and SII, respectively. In Ames test, sample SII was found to be lethal to Salmonella tester strains at all concentrations used, while sample SI was found to be mutagenic in TA100 strains of Salmonella typhimurium. Sample SII was found to be strongly acidic with pH 3.46. The present study focuses on the increasing heavy metal pollution in Amritsar city due to industrial discharges over lands and also infers that both bioassays Ames and A/RAAA can serve as first alert indication of pollution.     

Comparative study of leaching of silver nanoparticles from fabric and effective effluent treatment

Nano silver (Ag_n) is employed as an active antimicrobial agent, but the environmental impact of Ag_n released from commercial products is unknown. The quantity of nanomaterial released from consumer products during use should be determined to assess the environmental risks of advancement of nanotechnology. This work investigated the amount of silver released from three different types of fabric into water during washing. Three different types of fabric were loaded with chemically synthesized Ag nanoparticles and washed repeatedly under simulated washing conditions. Variable leaching rates among fabric types suggest that the manufacturing process may control the release of silver reaching the waste water treatment plants. In an attempt to recover the Ag_n for reutilization and to save it from polluting water, the effluents from the wash were efficiently treated with bacterial strains. This treatment was based on biosorption and was very efficient for the elimination of silver nanoparticles in the wash water. The process ensured the recovery of the Ag_n leached into the effluent for reutilization, thus preventing environmental repercussions.     

Bioefficacy of iprodione against two desapers, its compatibility with T. harzianum and residues on cabbage crop

Iprodione (3-(3,5-dichlorophenyl)-N-isopropyl-2,4-dioxoimidazolidine-1-carboxamide) bio-assayed against fungi Alternaria brassicicola and Sclerotinia sclerotiorum was found to be highly effective for inhibiting these desapers. Inhibition of A. brassicicola was 100% up to the dose of 75 ppm and for S. sclerotiorum there was 50% inhibition for the same concentration. Formulation of the pesticide was applied @ 500 and 1000 g. a.i./ha on the cabbage crop grown in the fields. Residues in the edible sample of cabbage were analyzed by gas choromatography for the fungicide and its metabolites. The dissipation of residues of the fungicide and its bio-efficacy against two fungi are presented. It dissipated from 3.72 to 0.072 microg/g on cabbage head by 15 days after treatment. The EC50 values of iprodione were found to be 11.5 ppm and 79.4 ppm for A. brassicicola and S. sclerotiorum, respectively. Half-life of iprodione was found to be 3 days for both cabbage head and leaves. The compatibility of the fungicide with a bio agent, T. harzianum was also studied and these two were not found to be compatible.     

An Experiment in Voluntary Environmental Regulation: Participation in EPA′s 33/50 Program

The U.S. EPA has initiated the 33/50 program to encourage firms to voluntarily reduce releases and transfers of 17 toxic chemicals. This paper evaluates the factors leading to participation in this program to assess its potential to augment more traditional command and control regulation. The results show that large firms with substantial toxic releases in unconcentrated industries are the most likely participants. The results also indicate that public information and awareness plays an important role and that EPA and other regulators can improve environmental performance by encouraging competition in environmental quality.     

Potable groundwater quality in some villages of Haryana, India: focus on fluoride

The fluoride concentration in ground water was determined in ten villages of Rohtak district of Haryana state (India). The fluoride concentration in the underground water of these villages varied from 0.034-2.09 mg/l. Various other water quality parameters, viz., pH, electrical conductivity, total dissolved salts, total hardness, total alkalinity sodium, potassium, calcium, magnesium, carbonate, bicarbonate, chloride and sulfate were also measured. A systematic calculation of correlation coefficients among different physicochemical parameters indicated considerable variations among the analyzed samples with respect to their chemical composition. Majority of the samples do not comply with Indian as well as WHO standards for most of the water quality parameters measured. Overall water quality was found unsatisfactory for drinking purposes. Fluoride content was higher than permissible limit in 50% samples.     

Persistence of carbaryl and its risk assessment through consumption of treated grapes

The average initial deposits of carbaryl were observed to be 1.4 and 3.1?mg?kg^?1, respectively, following four applications of the insecticide at 4.95 and 9.9?kg active ingredient per hectare. Residues of carbaryl dissipated below its limit of quantification of 50?µg?kg^?1 after 7 and 10 days at single and double the application dosage, respectively. The half-life values (t _1/2) of carbaryl were worked out to be 1.3 and 0.7 days, respectively, at single and double dosages. The acceptable daily intake (ADI) for carbaryl has been fixed at 8?µg?kg^?1 body weight per day. Keeping in view the residues of carbaryl observed one day after the last application, a child of 10?kg and an adult of 60?kg will have an intake of 77 and 154?µg carbaryl after consumption of 100 and 200?g grapes, in comparison to its ADI of 80 and 480?µg; thus, no health risk is to be expected. Therefore, a waiting period of 1 day has been suggested for the safe consumption of carbaryl-treated grapes to avoid any health hazards.     

Cement-based solidification/stabilization of lead-contaminated soil at a utah highway construction site

This article describes portland cement-based solidification/stabilization (S/S) treatment of heavy metal-contaminated soil. The soil was discovered during highway construction in West Jordan, Utah. Environmental Chemical Corporation (ECC) performed an emergency response to remediate the soil under contract with the EPA and the United States Bureau of Reclamation (USBR). The soil was treated by S/S. Treatment of the soil, contaminated with lead and arsenic, involved: (1) excavation, (2) size segregation, (3) reduction of oversized particles, (4) addition and mixture of portland cement and cement kiln dust, and (5) beneficial reuse of the treated soil as a subbase. S/S treatment successfully reduced Toxicity Characteristic Leaching Procedure (TCLP) concentrations of the contaminants to below regulatory levels.     

A HYDROCLIMATIC APPLICATION STRATEGY FOR THE POISSON PARTIAL DURATION MODEL1

ABSTRACT: A strategy for formulating and testing the Poisson partial duration extreme value model is presented. The procedure is demonstrated using recorded Streamflow series from a humid subtropical region of the southern United States. The observed data series are partitioned by climatic causes and tested for both the Poisson assumption and the validity of the exponential as marginal distributions. Several statistical tests are utilized in making these determinations. Some important aspects of the model as applied to humid climates are demonstrated. It was found that a majority of Streamflow series could be represented by the model and that significant differences do exist between the arrival structures of floods resulting from different climatic mechanisms. However, these differences generally do not exist in the distribution of the flood magnitudes. In addition, it is possible that model validity is restricted by drainage basin size.     

Biodiversity and present status of freshwater fishes in Lohit river basin of India

Lohit is a major tributary of the river Brahmaputra in India and is famous for its rich and diverse fish fauna. The river has a difficult terrain, but has high hydropower potential. A large number of storage-based hydropower plants are envisaged on this river in the near-future. This study aims at presenting the existing diverse fish fauna in Lohit river basin. A total of 74 fish species are identified in this river basin and can be classified into seven orders, 20 families, and 52 genera. Further, it has been highlighted that there are seven species which have been categorized as endangered, 12 species are categorized to be vulnerable, three species have been categorized as data-deficient, and the remaining species are in the least concern category. It is expected that the construction of proposed storage-based power plants in this basin will affect the flow and storage characteristics, as well as the temperature of the water, which, in turn, will affect the rich fish fauna. This study emphasizes the need for preparing a comprehensive plan for the adoption of appropriate in situ conservation measures, as well as an awareness program, so as to save the rich and diverse fish fauna of Lohit river basin.     

Novel degradation pathway of 4-chloro-2-aminophenol via 4-chlorocatechol in Burkholderia sp. RKJ 800

Burkholderia sp. RKJ 800 utilized 4-chloro-2-aminophenol (4C2AP) as the sole carbon and energy source and degraded it with release of chloride and ammonium ions. The metabolic pathway of degradation of 4C2AP was studied and a novel intermediate, 4-chlorocatechol was identified as a major degradation product of 4C2AP using high-performance liquid chromatography and gas chromatography–mass spectrometry. Enzyme activities for 4C2AP-deaminase and 4-chlorocatechol-1,2-dioxygenase were detected in the crude extracts of the 4C2AP-induced cells of strain RKJ 800. The activity of the 4C2AP-deaminase confirmed the formation of 4-chlorocatechol from 4C2AP and the 4-chlorocatechol-1,2-dioxygenase activity suggested the cleavage of 4-chlorocatechol into 3-chloro-cis,cis-muconate. On the basis of the identified metabolites, we have proposed a novel degradation pathway of 4C2AP for Burkholderia sp. RKJ 800. Furthermore, the potential of Burkholderia sp. RKJ 800 to degrade 4C2AP in soil was also investigated using microcosm studies under laboratory conditions. The results of microcosm studies conclude that Burkholderia sp. RKJ 800 was able to degrade 4C2AP in soil and may be used to remediate 4C2AP-contaminated site. This is the first report of (1) the formation of 4-chlorocatechol and 3-chloro-cis,cis-muconate in the degradation pathway of 4C2AP and (2) bioremediation of 4C2AP by any bacterium.