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21.
Mohan M Deepa M Ramasamy EV Thomas AP 《Environmental monitoring and assessment》2012,184(7):4233-4245
Mercury, a global pollutant, has become a real threat to the developing countries like India and China, where high usage of mercury is reported. Mercury and other heavy metals deposited in to the aquatic system can cause health risk to the biota. The common edible fishes such as Mugil cephalus, Arius arius, Lutjanus ehrenbergii, Etroplus suratensis were collected from Cochin backwaters, Southwest India and analysed for mercury and other heavy metals (zinc, cadmium, lead and copper) in various body parts. Kidney and liver showed highest concentration of metals in most fishes. The omnivore and bottom feeder (E. suratensis) showed high concentration of mercury (14.71 mg/kg dry weight) and other metals (1.74 mg/g-total metal concentration). The average mercury concentration obtained in muscle was 1.6 mg/kg dry weight (0.352 mg/kg wet weight), which is higher than the prescribed limits (0.3 mg/kg wet weight). The concentration of other heavy metals in the muscles of fishes were found in a decreasing order Zn>Cu>Cd>Pb and are well below WHO permissible limits that were safe for human consumption. Metal selectivity index (MSI) obtained for all the metals except mercury showed that both carnivores and omnivores have almost same kind of affinity towards the metals especially Zn and Cd, irrespective of their feeding habit. The MSI values also indicate that the fishes have the potential to accumulate metals. High tissue selectivity index (TSI) values were reported for kidney, muscle and brain for all metals suggests that the metal concentration in these tissues can serve as an indication of metal polluted environment. Even if the daily intakes of Zn, Cd, Pb and Cu from these fishes are within the provisional maximum daily intake recommended by WHO/FAO, the quality is questionable due to the high hazard index obtained for mercury (>1). Fishes like E. suratensis being a favourite food of people in this region, the high consumption of it can lead to chronic disorders as this fish has high concentration of metals. 相似文献
22.
James M. McDade Poonam R. Kulkarni M. Ahmad Seyedabbasi Charles J. Newell Deepa Gandhi John D. Gallinatti Virgilio Cocianni Du'Bois J. Ferguson 《补救:环境净化治理成本、技术与工艺杂志》2013,23(2):71-91
Despite the installation in the 1980s and 1990s of hydraulic containment systems around known source zones (four slurry walls and ten pump‐and‐treat systems), trichloroethene (TCE) plumes persist in the three uppermost groundwater‐bearing units at the Middlefield‐Ellis‐Whisman (MEW) Superfund Study Area in Mountain View, California. In analyzing TCE data from 15 recovery wells, the observed TCE mass discharge decreased less than an order of magnitude over a 10‐year period despite the removal of an average of 11 pore volumes of affected groundwater. Two groundwater models were applied to long‐term groundwater pump‐and‐treat data from 15 recovery wells to determine if matrix diffusion could explain the long‐term persistence of a TCE plume. The first model assumed that TCE concentrations in the plume are controlled only by advection, dispersion, and retardation (ADR model). The second model used a one‐dimensional diffusion equation in contact with two low‐permeability zones (i.e., upper and lower aquitard) to estimate the potential effects of matrix diffusion of TCE into and out of low‐permeability media in the plume. In all 15 wells, the matrix diffusion model fit the data much better than the ADR model (normalized root mean square error of 0.17 vs. 0.29; r2 of 0.99 vs. 0.19), indicating that matrix diffusion is a likely contributing factor to the persistence of the TCE plume in the non‐source‐capture zones of the MEW Study Area's groundwater‐extraction wells. © 2013 Wiley Periodicals, Inc. 相似文献
23.
Tiku DK Kumar A Sawhney S Singh VP Kumar R 《Environmental monitoring and assessment》2007,132(1-3):453-466
India has a large number of paper manufacturing units, with mills varying in size of operations and type of product, scattered
all over the length and breadth of the country. Present study deals with the survey of four different pulp and paper mills
(Mill A, Mill B, Mill C and Mill D) in India, differing in their scale of operation as well as raw material usage. Physico-chemical
characterization of wastewaters produced by different processing units like digestor house liquors, bleaching section, paper
machine backwaters, combined inlet to the ETP and outlet to ETP, for all the four mills, was conducted. Different parameters
like pH, Color, COD, BOD, percent Na, SAR, TDS and Total hardness were analyzed and compared. Highly significant differences
were thus found between all the processing units of all four mills with p values < 0.01. This evaluation showed that though these mills have effluent treatment facilities installed in their premises,
improvements are still needed to increase their efficiencies for treating the discharged wastewaters. 相似文献
24.
The concentrations of Cr, Pb, Zn, Cu, Ni and Cd wereanalyzed by Atomic Absorption Spectrophotometer in thescalp hair of professional male autodrivers who areoccupationally exposed to the vehicular/industrialpollutants in the industrial city of Coimbatore, TamilNadu. The unwashed hair samples when compared with thewashed hair showed a significantly higher levels of Cr,Zn and Pb. The correlation coefficient showed a strongmutual dependence on the scalp hair of the exposedindividuals and no correlation was found among the tracemetals except for Ni–Pb and Ni–Cd. The results ingeneral showed a positive exogenous contribution of allthe analyzed industrial trace metals. The drivers who are occupationally exposed to vehicular/industrial pollution are at risk. 相似文献
25.
Mohapatra S Ahuja AK Deepa M Jagadish GK Rashmi N Sharma D 《Journal of environmental science and health. Part. B》2011,46(3):264-271
Flubendiamide is a new insecticide that has been found to give excellent control of lepidopterous pests of tomato. This study has been undertaken to develop an improved method for analysis of flubendiamide and its metabolite des-iodo flubendiamide and determine residue retention in tomato and soil. The analytical method developed involved extraction of flubendiamide and its metabolite des-iodo flubendiamide with acetonitrile, liquid-liquid partitioning into hexane-ethyl acetate mixture (6:4, v v?1) and cleanup with activated neutral alumina. Finally the residues were dissolved in gradient high pressure liquid chromatography (HPLC) grade acetonitrile for analysis by HPLC. The mobile phase, acetonitrile-water at 60:40 (v v?1) proportion and the wavelength of 235 nm gave maximum peak resolution. Using the above method and HPLC parameters described, nearly 100 % recovery of both insecticides were obtained. There was no matrix interference and the limit of quantification (LOQ) of the method was 0.01 mg kg?1. Initial residue deposits of flubendiamide on field-treated tomato from treatments @ 48 and 96 g active ingredient hectare?1 were 0.83 and 1.68 mg kg?1, respectively. The residues of flubendiamide dissipated at the half-life of 3.9 and 4.4 days from treatments @ 48 and 96 g a.i. ha?1, respectively and persisted for 15 days from both the treatments. Des-iodo flubendiamide was not detected in tomato fruits at any time during the study period. Residues of flubendiamide and des-iodo flubendiamide in soil from treatment @ 48 and 96 g a.i. ha?1 were below detectable level (BDL, < 0.01 mg kg?1) after 20 days. Flubendiamide completely dissipated from tomato within 20 days when the 480 SC formulation was applied at doses recommended for protection against lepidopterous pests. 相似文献
26.
California's regulatory agencies have historically been at the forefront of national efforts to address environmental concerns. In 2012, California's agency for addressing leaking underground fuel tanks (LUFTs) adopted a policy that identifies low‐threat conditions warranting closure of an LUFT case. That development clearly fulfills the role of risk management in the risk assessment–risk management paradigm inherent in environmental remediation. It also encourages identification of additional categories of sites and other circumstances that are “low threat” to develop similar guidance on closure to apply to those sites. ©2015 Wiley Periodicals, Inc. 相似文献
27.
Remediation of contaminated sites has focused largely on restoration of groundwater aquifers. Often the stated remedial goal is to achieve conditions allowing unrestricted use and unrestricted exposure. Such total groundwater cleanup has occurred at some sites, but is the exception rather than the rule. At the same time, significant effort occurs to perform risk assessments for potential exposure to contaminants in groundwater at sites, both before and after remediation. The logical synergy between risk assessment and remediation is for risk management to seek opportunities for optimal use of groundwater based upon realistic expectations of cleanup technologies and the relevant acceptable residual (postremediation) levels of contaminants. This article explores an approach to improve this synergistic relationship between risk assessment, risk management, and remediation for groundwater cleanups. ©2015 Wiley Periodicals, Inc. 相似文献
28.
New repellent semiochemicals for three species of
<Emphasis Type="Italic">Dendroctonus</Emphasis> (Coleoptera: Scolytidae) 总被引:1,自引:0,他引:1
Summary. Nine compounds identified from captured
volatiles of the Douglas-fir beetle, Dendroctonus pseudotsugae,
the mountain pine beetle, D. ponderosae, and the
spruce beetle, D. rufipennis, that elicited antennal responses
in males and females of one or more of these species were
tested in the field to determine behavioural activity.
1-Octen-3-ol, found in the volatiles of females of all three
species decreased the response of male and female coastal
and male interior D. pseudotsugae and both sexes of D. ponderosae
to their aggregation pheromones. Acetophenone,
identified in the volatiles of females of all three species,
significantly decreased the response of interior female
D. pseudotsugae. trans-Verbenol, a potent aggregation
pheromone of D. ponderosae, decreased the response of both
sexes of D. pseudotsugae, while 3-methyl-2-cyclohexen-1-
one (MCH), the antiaggregation pheromone of D. pseudotsugae
and D. rufipennis decreased the response of both sexes
of D. ponderosae. While it has been demonstrated that semiochemical
mediated interspecific communication occurs
among bark beetles infesting the same host, this study
demonstrates that beetles can perceive signals emitted by
heterospecifics attacking nonhosts and can potentially use
them to avoid attacking the wrong species of conifer. 相似文献
29.
Electrochemical sensors for environmental monitoring: design, development and applications 总被引:1,自引:0,他引:1
The advancement in miniaturization and microfabrication technology has led to the development of sensitive and selective electrochemical devices for field-based and in situ environmental monitoring. Electrochemical sensing devices have a major impact upon the monitoring of priority pollutants by allowing the instrument to be taken to the sample (rather than the traditional way of bringing the sample to the laboratory). Such devices can perform automated chemical analyses in complex matrices and provide rapid, reliable and inexpensive measurements of a variety of inorganic and organic pollutants. Although not exhaustive due to the vast amounts of new and exciting electrochemical research, this review addresses many important advances in electrochemical sensor design and development for environmental monitoring purposes. Critical design factors and development issues including analytical improvements (e.g. detection limits), microfabrication and remote communication are presented. In addition, modern environmental applications will be discussed and future perspectives considered. 相似文献
30.
Fabrizia Ratto Tom D. Breeze Lorna J. Cole Michael P. D. Garratt David Kleijn Bill Kunin Denis Michez Rory O'Connor Jeff Ollerton Robert J. Paxton Guy M. Poppy Simon G. Potts Deepa Senapathi Rosalind Shaw Lynn V. Dicks Kelvin S.-H. Peh 《Conservation biology》2022,36(4):e13886
Pollinator declines have prompted efforts to assess how land-use change affects insect pollinators and pollination services in agricultural landscapes. Yet many tools to measure insect pollination services require substantial landscape-scale data and technical expertise. In expert workshops, 3 straightforward methods (desk-based method, field survey, and empirical manipulation with exclusion experiments) for rapid insect pollination assessment at site scale were developed to provide an adaptable framework that is accessible to nonspecialist with limited resources. These methods were designed for TESSA (Toolkit for Ecosystem Service Site-Based Assessment) and allow comparative assessment of pollination services at a site of conservation interest and in its most plausible alternative state (e.g., converted to agricultural land). We applied the methods at a nature reserve in the United Kingdom to estimate the value of insect pollination services provided by the reserve. The economic value of pollination services provided by the reserve ranged from US$6163 to US$11,546/year. The conversion of the reserve to arable land would provide no insect pollination services and a net annual benefit from insect-pollinated crop production of approximately $1542/year (US$24∙ha–1∙year–1). The methods had wide applicability and were readily adapted to different insect-pollinated crops: rape (Brassica napus) and beans (Vicia faba) crops. All methods were rapidly employed under a low budget. The relatively less robust methods that required fewer resources yielded higher estimates of annual insect pollination benefit. 相似文献