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Groundwater is used as a drinking-water supply by about one-half of the U.S. population, including almost all people residing in rural areas. As estimated by the U.S. Geological Survey (USGS) [...], BACKGROUND: As the population and demand for safe drinking water from domestic wells increase, it is important to examine water quality and contaminant occurrence. A national assessment in 2006 by the U.S. Geological Survey reported findings for 55 volatile organic compounds (VOCs) based on 2,401 domestic wells sampled during 1985-2002. OBJECTIVES: We examined the occurrence of individual and multiple VOCs and assessed the potential human-health relevance of VOC concentrations. We also identified hydrogeologic and anthropogenic variables that influence the probability of VOC occurrence. METHODS: The domestic well samples were collected at the wellhead before treatment of water and analyzed for 55 VOCs. Results were used to examine VOC occurrence and identify associations of multiple explanatory variables using logistic regression analyses. We used a screening-level assessment to compare VOC concentrations to U.S. Environmental Protection Agency maximum contaminant levels (MCLs) and health-based screening levels. RESULTS: We detected VOCs in 65% of the samples; about one-half of these samples contained VOC mixtures. Frequently detected VOCs included chloroform, toluene, 1,2,4-trimethylbenzene, and perchloroethene. VOC concentrations generally were < 1 µg/L. One or more VOC concentrations were greater than MCLs in 1.2% of samples, including dibromochloropropane, 1,2-dichloropropane, and ethylene dibromide (fumigants); perchloroethene and trichloroethene (solvents); and 1,1-dichloroethene (organic synthesis compound). CONCLUSIONS: Drinking water supplied by domestic wells is vulnerable to low-level VOC contamination. About 1% of samples had concentrations of potential human-health concern. Identifying factors associated with VOC occurrence may aid in understanding the sources, transport, and fate of VOCs in groundwater. KEY WORDS: domestic wells, drinking-water quality, human health, volatile organic compounds. Environ Health Perspect 115:1539-1546 (2007). doi:10.1289/ehp.10253 available via http://dx.doi.org/ [Online 20 August 2007]

Concentrations of methyl tert-butyl ether (MTBE) in groundwater samples collected from five drinking water wells, 12 springs and 193 monitoring wells in urban areas during 1993-1994 do not pose health risks to humans in most cases. MTBE is the most commonly used fuel oxygenate and is a new gasoline additive. Although it was the second most frequently detected chemical in the samples, only 3% of the shallow wells and springs in urban areas had MTBE concentrations that exceeded 20 ug/L, the estimated lower limit of the EPA's draft drinking water health advisory. The samples were collected as part of the National Water Quality Assessment program of the US Geological Survey.

Examines postprogram experiences of minority youth in the National Urban League Youth Career Development Project. Results confirmed the difficulties minority female teenagers have obtaining jobs. Found parents' employment status had little effect, and unemployed youth tended to rely on informal job search techniques. (Author/JAC)

Reviews the educational and legal history of Black education; criticizes the emphasis on achievement scores as a predominant variable in the measurement of such programs; and states that conclusions about Black enrollment, retention, and successful matriculation are generally positive. (Author/MLF)