Backyard chicken ownership is rapidly increasing in urban areas in the United States, largely as a way to provide eggs for household consumption. Despite elevated levels of environmental lead contamination in many US cities, the role of backyard chicken eggs as a pathway for lead exposure, particularly for children, has received limited scrutiny. To characterize lead exposure from consumption of backyard chicken eggs for children and predict related effects on blood lead level (BLL), we conducted a cross-sectional study of backyard chicken owners in the Greater Boston area (n = 51).
View Article and Find Full Text PDFBackground: The oil-rich Niger Delta suffers from extensive petroleum contamination. A pilot study was conducted in the region of Ogoniland where one community, Ogale, has drinking water wells highly contaminated with a refined oil product. In a 2011 study, the United Nations Environment Programme (UNEP) sampled Ogale drinking water wells and detected numerous petroleum hydrocarbons, including benzene at concentrations as much as 1800 times higher than the USEPA drinking water standard.
View Article and Find Full Text PDFEnviron Health Perspect
February 2011
Background: Methylmercury (MeHg) exposure assessments among average fish consumers in the United States may underestimate exposures among U.S. subpopulations with high intakes of regionally specific fish.
View Article and Find Full Text PDFWe conducted a sensitivity analysis of the commonly employed pressure-based direct integrity test (DIT), the most sensitive test for defects in low-pressure hollow fiber (LPHF) microfiltration and ultrafiltration systems used in drinking water treatment. Incorporating uncertainty to assess the practice of DIT, we find the resolution in some tests may be insufficient to verify the presence of a barrier to oocysts of Cryptosporidium. Applying distributions and boundaries derived from literature and practice, we solved for the defect size resolution (DSR) using Monte Carlo and Probability Bounds Analysis for five commercial membrane designs.
View Article and Find Full Text PDFWe identify, categorize, and score sources of uncertainty in human health and ecological risk assessments conducted for several US Army sites to identify better analytical practices and opportunities for targeted research to improve risk estimates. The reviewed assessments are from reports completed within the past 8 y and were obtained from the US Army Environmental Technical Information Center (ETIC) at Aberdeen Proving Ground, Maryland, USA. Most of the risk assessments incorporated only qualitative uncertainty analysis to demonstrate the conservatism of selected data and predictive models.
View Article and Find Full Text PDFIntegr Environ Assess Manag
October 2007
Measurements of polychlorinated biphenyl (PCB) congener concentrations and profiles from produce grown near New Bedford Harbor, Massachusetts, USA, before, during, and after remediation of PCB-contaminated sediment are presented. Samples of tomatoes collected from locations upwind and downwind relative to harbor contamination are compared with the use of measurements of 47 individual PCB congeners. The PCB concentration in the locally grown tomatoes, as expressed by the sum of congeners, is highest during the period of harbor dredging and drops to its lowest point after remediation, which included dredging and excavation.
View Article and Find Full Text PDFBiomagnification of organochlorine and other persistent organic contaminants by higher trophic level organisms represents one of the most significant sources of uncertainty and variability in evaluating potential risks associated with disposal of dredged materials. While it is important to distinguish between population variability (e.g.
View Article and Find Full Text PDFInvestigation of pesticide impacts on human health depends on good measures of exposure. Historical exposure data are needed to study health outcomes, such as cancer, that involve long latency periods, and other outcomes that are a function of the timing of exposure. Environmental or biological samples collected at the time of epidemiologic study may not represent historical exposure levels.
View Article and Find Full Text PDF