Seasonal Dynamics of Dissolved Metals in Surface Coastal Waters of Southwest India

Spatial and temporal variations in concentration of dissolved metals viz. Copper (Cu), Lead (Pb), Chromium (Cr), Nickel (Ni), Zinc (Zn), Cadmium (Cd) and Mercury (Hg) in surface waters of southwest coast of India were studied. Concentrations of metals showed an aberration both temporally and spatially. Seasonal average concentrations of the analyzed metals followed the order Zn > Ni > Cu > Pb > Cd > Cr > Hg. The degree of contamination due to metal was determined by comparison with coastal water quality criteria. It established enrichment of Cu, Zn, Ni and Hg due to anthropogenic influence along southwest coast of India.     

Swedish and Lithuanian Students' Experience of Their Rights

One important implication of the UN Convention on the Rights of the Child is that every child should be part of democratic society. In the present empirical study, students' (aged 12–14, 16–18) conceptions of democracy in two Swedish and two Lithuanian schools are compared. Comparisons on age and gender are also examined. The analysis shows certain similarities in the Sweden and Lithuanian students' concept of democracy, but differences emerge.     

Polychlorinated Naphthalenes and Other Organochlorine Contaminants in Swedish Human Milk, 1972–1992

The concentrations of polychlorinated naphthalenes (PCNs) were determined together with polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), 1,1-bis-(4-chlorophenyl)-2,2,2-trichloroethane (p,p′-DDT), 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p′-DDE) and hexachlorobenzene (HCB) in milk, sampled in the course of 1972–92 from mothers living in Stockholm. A previously developed method for multicomponent analysis of organochlorine environmental contaminants was adapted for simultaneous analysis of PCNs. The mean recoveries of seven chlorinated naphthalene (CN) congeners added to milk prior to extraction were 76–99%. Similar recoveries were obtained for the commercial PCN product Halowax 1014. The pattern of PCNs in milk differed to a great extent from that in the commercial PCN products. The dominating congeners in breast milk were 1,2,3,5,7-pentachloronaphthalene (CN-52), 1,2,3,4,6,7- and/or 1,2,3,5,6,7-hexachloronaphthalene (CN-66/CN-67) and one unidentified tetrachloronaphthalene. There was a notable decrease in the concentrations of PCNs as was of the other organochlorine contaminants in milk from 1972 to 1992. During this time period the sum of CN congeners decreased from 3,081 to 483 pg/g milk fat and the sum of toxic equivalents of dioxin and dioxin-like compounds decreased from 100 to 39 pg/g milk fat. Received: 5 June 1997/Accepted: 20 October 1997     

Profiles of Organochlorine Pesticides in Earthworms from Urban Leisure Areas of Beijing, China

In this study, organochlorine pesticides (HCHs and DDTs) in earthworm and soil contacted closely with it were determined for the purpose of the risk assessment of chemicals in the urban leisure environment. The level of total hexachlorocyclohexanes and (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in earthworms was 0.6500–44.78 ng g⁻¹ and 18.97–1.112 × 104 ng g⁻¹, respectively. Absolutely high levels of DDT and its metabolites in earthworm and correlative soils samples, and the bioaccumulation factor (BAF) of DDTs probably presents certain risk to the higher trophic organisms through its food chain, especially birds.     

Fate of Triclosan and Triclosan-Methyl in Sewage TreatmentPlants and Surface Waters

The fate of triclosan in diverse stages of two sewage treatment processes has been determined. The elimination process differed considerably depending on the technology applied in the respective sewage treatment plant (STP). The plant operating with a two-stage biologic (activated sludge) process removed triclosan more efficiently than the STP with a combination of physical and activated sludge process. The treatment in the aeration basin was the dominant elimination mechanism, whereas the final biologic filter was not very effective. The elimination rates for triclosan were 87% and 95%, respectively. These data were compared with emissions of a multitude of STPs in the river Ruhr catchment area as well as triclosan and its known transformation product, triclosan-methyl, in the river. The concentrations of both compounds were between <3 and 10 ng/L in true surface-water samples for triclosan and between 0.3 and 10 ng/L for triclosan-methyl. The STP effluents held higher concentrations (10 to 600 ng/L triclosan). The ratio of triclosan to triclosan-methyl did not change significantly within the longitudinal profile of the river, but diverse STPs discharging to the river exhibited individual triclosan–to–triclosan-methyl ratios. From the riverine concentration data, in-river elimination rates and half-life were estimated.     

Occurrence of Glyphosate in Surface Waters of Southern Ontario

Glyphosate in surface waters of southern Ontario (Canada) was studied over a 2-year period. A small percentage of samples exhibited glyphosate concentrations greater than the analytical limit of quantitation (17 microg a.e./L), and the maximum concentration of glyphosate measured was 40.8 microg/L. No samples of roughly 500 analyzed exceeded the Canadian Water Quality Guideline of 65 microg a.e./L considered protective of aquatic life. Typical concentrations of glyphosate in amphibian habitats were well below a range of toxicity thresholds for aquatic organisms, and were thus judged to be unlikely to pose a substantial risk to either sensitive amphibian larvae or other aquatic biota.     

Occurrence and Distribution of Hexavalent Chromium in Ground and Surface Waters in Cyprus

The origin and distribution of hexavalent chromium, Cr (VI) over four seasonal cycles was investigated through a conceptual model that included three aquifer systems in Cyprus. An extensive water sampling grid covered two sea water intruded coastal aquifers, namely the Kokkinochoria (A1) and Kiti-Pervolia (A2) aquifers and the Troodos massif (A3). Analytical results give a first insight to the presence of Cr (VI) in Cyprus ground and surface waters. The highest Cr (VI) value of 26 μg L⁻¹ is observed in the Troodos area (A3) where Cr(VI) is detected in all sampled water systems (surface and ground/spring). Nonetheless, the highest median values of 4.6 and 4.5 μg L⁻¹ are observed in the Kokkinochoria (A1) and Kiti-Pervolia (A2) study areas respectively, where the local aquifers are under increased pressure from agriculture, urbanization and seawater intrusion. Stable isotopes were used to discern the effect of return irrigation and seawater intrusion. Stable isotope analyses from Troodos samples show two distinct groups of meteoric and near meteoric waters whereas isotopically enriched water is shown to correspond to the Kiti and Kokkinochoria area.

     

Global Pollution Monitoring of PCBs and Organochlorine Pesticides Using Skipjack Tuna as a Bioindicator

Concentrations of organochlorines (OCs) representing persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), chlordane compounds (CHLs), hexachlorocyclohexane isomers (HCHs), and hexachlorobenzene (HCB), were determined in the liver of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters of various regions in the world (offshore waters around Japan, Taiwan, Philippines, Indonesia, Seychelles, and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Bay of Bengal, and the North Pacific Ocean). OCs were detected in livers of all of the skipjack tuna collected from the locations surveyed, supporting the thesis that there is widespread contamination of persistent OCs in the marine environment. Within a location, no significant relationship between growth-stage (body length and weight) and OC concentrations (lipid weight basis) was observed, and the OC residue levels were rather uniform among the individuals. Interestingly, the distribution of OC concentrations in skipjack tuna was similar to those in surface seawaters from which they were taken. These results suggest that OC concentrations in skipjack tuna could reflect the pollution levels in seawater from which they are collected and that this species is a suitable bioindicator for monitoring the global distribution of OCs in offshore waters and the open ocean. Concentrations of PCBs and CHLs in skipjack tuna were higher in offshore waters around Japan (up to 1100 and 250 ng/g lipid wt, respectively), suggesting the presence of sources of PCBs and CHLs in Japan. High concentrations of DDTs and HCHs were observed in samples from the Japan Sea, the East China Sea, the South China Sea, and the Bay of Bengal (up to 1300 and 22 ng/g lipid wt, respectively). This result suggests recent use of technical DDT and HCH for agricultural and/or public health purposes in Russia, China, India, and some other developing Asian countries. Relatively high concentrations of PCBs, CHLs, HCHs, and HCB were also observed in samples collected from some locations in the middle of the Pacific Ocean, indicating the expansion of OC contamination on a global scale. Considering these facts, continuous studies monitoring these compounds in offshore waters and the open seas, using skipjack tuna as a bioindicator, are needed to further understand the future trend of contamination.     

Assessment of 20 Organochlorine Pesticides (OCPs) Pollution in Suburban Soil in Tianjin, China

Soil contamination with organochlorine pesticides has aroused worldwide concerns considering their high toxicities and long-term persistence. In this study, 87 representative soil samples from suburban areas (Xiqing, Dongli, Jinnan, Beichen) of Tianjin, the third biggest city in China, were collected to evaluate the pollution of 20 organochlorine pesticides. Surface soil samples were air-dried and sieved. Ultrasonic extraction was used for organochlorine pesticides preparation prior to analysis with gas chromatography–mass spectrometry. It was revealed that p,p′-DDE, p,p′-DDD, o,p′-DDT, o,p′-DDD, hexachlorobenzene, dicofol and β-HCH were seven pesticides detected most frequently. DDTs, HCHs and hexachlorobenzene were the predominant pesticide pollutants in soil. Spatial variation of these organochlorine pesticides in soil was illustrated; Pollution levels, characteristics and possible sources were also investigated. Most of other 13 kinds of pesticides were detected and the frequencies of detection were calculated to reveal the pollution status, which ranged from 0.0% (aldrin, dieldrin and endrin) to 34.5% (p,p′-DDT). These data were helpful to figure out the pollution of organochlorine pesticides and could be further used to evaluate the health risk associated with soil pollution.     

Levels of Organochlorine Compounds in Bivalves from the Japanese Coastal Waters: Results from the Environmental Specimen Bank in Japan

No abstract available.     

晋阳湖游泳场水HBsAg的污染及对水产养殖场水体的影响

本文对晋阳湖游泳场ＨＢｓＡｇ污染及其对水产养殖场水体的影响进行了调查。结果，游泳场水合计ＨＢｓＡｇ阳性率为４０％，且下层水ＨＢｓＡｇ阳性率明显高于中层水，整个湖水水体污染情况接近，湖水ＨＢ－ｓＡｇ阳性率为５０％，淤泥为１００％，且淤泥中的ＨＢｓＡｇ约为水中的一万倍，结论为游泳场水ＨＢｓＡｇ的污染波及到整个湖水，间接证明淤泥是病毒聚积的场所，它的再悬浮对水体的污染有重大影响。     

Evaluation of Bioassays to Monitor Surface Microlayer Toxicity in Tropical Marine Waters

Bioassays were developed, using embryos of: coral, Montastraea faveolata; graysby, Epinephelus cruentatus; grouper, Epinephelus adscensionis x gruttatus (hybrid); queen conch, Strombus gigas; rock-boring urchin, Echinodermata lucunter; spotted seatrout, Cynoscion nebulosus; variegated urchin, Lytechinus variegatus; winged pearl oyster, Pteria colymbus; and yellowtail snapper, Ocyurus chrysurus. Relative sensitivities and precison of various species-endpoint combinations were evaluated using three reference toxicants: copper, sodium dodecyl sulfate, and Dibrom?. The 24-h P. colymbus embryo test had the best overall sensitivity and exhibited a high degree of precision. However, oyster embryos were difficult to obtain and did not aggregate at the air–water interface. Therefore, the P. colymbus embryo test was deemed unsuitable for use as a bioassay for monitoring sea-surface microlayer (SSML) toxicity. Tests based on normal development of L. variegatus to the early pluteus 3 stage and percent normal-live C. nebulosus larvae at 48 h were relatively sensitive and exhibited good replicability and repeatability. The L. variegatus urchin embryo test was also found to be highly reproducible. The results of this comparative study indicated that L. variegatus and C. nebulosus were suitable surrogates for coral-reef species in toxicity assessments of the SSML. Received: 28 May 1996/Revised: 10 August 1996     

Pesticides in Surface Waters in Argentina Monitored Using Polar Organic Chemical Integrative Samplers

Bulletin of Environmental Contamination and Toxicology - Polar Organic Chemical Integrative Samplers (POCIS) were deployed in two watersheds in Córdoba province and one watershed in Buenos...