Pesticides in Ground Water of Central and Western Maryland
Selected pesticides and degradates (products of pesticide degradation) are detectable in ground water in many parts of central and western Maryland, although concentrations are generally less than 0.1 micrograms per liter. Ground-water samples collected recently (1994–2003) from 72 wells in areas of Maryland underlain by consolidated carbonate, crystalline, or siliciclastic aquifers (areas north and west of the Fall Line) were analyzed for selected pesticides and degradates. Pesticides were typically detected in mixtures of multiple compounds in ground water, and degradates were commonly detected, often at greater concentrations than their respective parent compounds. No pesticides were observed at concentrations greater than established standards for drinking water, and nearly all observed concentrations were below other health-based guidelines. Although such standards and guidelines are generally much greater than measured concentrations in ground water, they do not exist for many detected compounds (particularly degradates), or for mixtures of multiple compounds. The distribution of pesticides and degradates in ground water is related to application practices, as well as chemical and environmental factors that affect the fate and movement of individual compounds.
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- Central and Western Maryland
- Measuring Pesticides in Ground Water
- Pesticides in Ground Water of Central and Western Maryland
- Ground Water and Drinking Water
- Discussion and Implications
- References Cited
For more information about USGS activities in Maryland,
and the District of Columbia contact:
MD-DE-DC Water Science Center
U.S. Geological Survey
5522 Research Park Drive
Baltimore, MD 21228
Telephone: (443) 498-5500
Fax: (443) 498-5510
or access the USGS Water Resources of Maryland, Delaware,
and District of Columbia home page at: http://md.water.usgs.gov/.