Environmental research
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Environmental research · Jan 2005
Comparative StudyCan we use fixed ambient air monitors to estimate population long-term exposure to air pollutants? The case of spatial variability in the Genotox ER study.
Associations between average total personal exposures to PM2.5, PM10, and NO2 and concomitant outdoor concentrations were assessed within the framework of the Genotox ER study. It was carried out in four French metropolitan areas (Grenoble, Paris, Rouen, and Strasbourg) with the participation, in each site, of 60-90 nonsmoking volunteers composed of two groups of equal size (adults and children) who carried the personal Harvard Chempass multipollutant sampler during 48 h along two different seasons ("hot" and "cold"). In each center, volunteers were selected so as to live (home and work/school) in three different urban sectors contrasted in terms of air pollution (one highly exposed to traffic emissions, one influenced by local industrial sources, and a background urban environment). ⋯ Comparison of personal exposures to PM or NO2 with ambient air levels is inherently disturbed by indoor sources and activities patterns. Discrepancies between measurement devices and local and regional sources of pollution may also strongly influence how the ambient air concentrations relate to population exposure. Much attention should be given to the selection of the most appropriate monitoring sites according to the study objectives.
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Environmental research · Sep 2004
Dioxin-like components in human breast milk collected from Hong Kong and Guangzhou.
The H4IIE rat hepatoma cell line was employed as a cell model to screen 7-ethoxyresorufin O-deethylase (EROD)-TCDD equivalents (EROD-TEQ) of human breast milk samples collected from Hong Kong and Guangzhou, China. The screening methods employed a 96-well plate spectrofluorometer-EROD assay. For cell-line validation, our results demonstrated a dose-dependent increase in the Ah receptor-mediated response (i.e., CYP1A1 mRNA and EROD) of the cells upon exposure to a number of known Ah receptor agonists, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,7,8-tetrachlorodibenzothiophene, benzo[a]pyrene, and beta-naphthaflavone. ⋯ However, the mean and median EROD-TEQ values of the Guangzhou population were in general higher than those of the Hong Kong population. The results of the present study indicate that it is feasible to use the H4IIE cell-line as a model for screening dioxin-like compounds in human breast milk. In addition, the method is rapid and cost-effective, particularly for a routine and high-throughput sample screening analysis, compared to the costly and time-intensive chemical analytical techniques.
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Environmental research · Jan 2001
Neurobehavioral deficits in Persian Gulf veterans: additional evidence from a population-based study.
Reports of low-concentration nerve gas exposures during the Gulf War (GW) have spurred concern about possible health consequences and symptoms reported by many returning veterans. The Portland Environmental Hazards Research Center is studying veterans from the northwest United States who report persistent, unexplained "Gulf War" symptoms (cases) and those who do not report those symptoms (controls). An epidemiological survey focused on exposures and symptoms was mailed to a random sample of GW veterans from Oregon and southwestern Washington. ⋯ However, the larger group of symptomatic veterans do have highly significant and compelling evidence of psychological distress based on scores from 11 separate psychological tests. Whereas the cases differed from the controls by poorer neurobehavioral test performance, extraction of the slow ODTP participants (almost all cases) eliminated neurobehavioral performance differences between the remaining cases and the controls and provided support for the hypothesis that the slow ODTP cases might have been from the unhealthy end of the GW population prior to the war. However, there was no evidence of poor motivation, pre-GW educational differences, or greater association with abnormal psychological function in this group than in other cases or controls.
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As the first report of the environmental fluoride level in Tibet, the determination by the fluoride ion-selective electrode method of fluoride concentration in water, soil, fuel, grains, food, vegetables, and tea was made for the Tibetan people living on various land types with various ecological characteristics. The average level of fluoride concentration in water in Tibet was 0.06 mg/L; the level of dissolved fluoride in the soil was 0.45 mg/kg; the fluoride concentration in main fuels was 0.10 mg/kg; the levels in main grains, food, and vegetables were 0.06-0.33 mg/kg; those in buttered tea and Zanba mixed with brick tea were 3.09-3.61 mg/kg; and water-dissolved fluoride concentrations in the brick tea produced in Sichuan Province and Yunan Province were 533.89-617.32 mg/kg. Tibet is the prevailing area of brick tea fluorosis.
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Environmental research · Feb 1999
Relation of Lake Ontario fish consumption, lifetime lactation, and parity to breast milk polychlorobiphenyl and pesticide concentrations.
Lactating female members and spouses of male members of the New York State Angler Cohort who agreed to provide breast milk samples were the subjects of this study. Questionnaires were provided to participants focusing on Lake Ontario fish consumption, reproductive history, and lactation history. Milk samples were analyzed for 77 polychlorinated biphenyls (PCB) congeners, 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (DDE), a metabolite of dichlorodiphenyltrichloroethane (DDT), hexachlorobenzene (HCB), and 1,1a,2,2,3,3a, 4,5,5,5a,5b,6-dodecachlorooctahydro-1,3, 4-methano-1H-cyclobuta[cd]pentalene (Mirex). ⋯ The total number of months of lifetime lactation varied inversely with the total PCB concentration in breast milk. A similar relationship was evident for DDE. These data are of use for risk assessment in estimating the relative exposure to these environmental contaminants in breast fed infants whose mothers consumed contaminated Lake Ontario fish.