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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Historical Use of Lead Arsenate and Survey of Soil Residues in Former Apple Orchards in Virginia

Schooley, Therese Nowak 15 August 2006 (has links)
Inorganic pesticides including natural chemicals such as arsenic, copper, lead, and sulfur have been used extensively to control pests in agriculture. Lead arsenate (PbHAsO4) was first used in apple orchards in the late 1890's to combat the codling moth, Cydia pomonella (Linnaeus). The affordable and persistent pesticide was applied in ever increasing amounts for the next half century. The persistence in the environment in addition to the heavy applications during the early 1900's may have led to many of the current and former orchards in this country being contaminated. In this study, soil samples were taken from several apple orchards across the state, ranging from Southwest to Northern Virginia and were analyzed for arsenic and lead. Based on naturally occurring background levels and standards set by other states, two orchards sampled in this study were found to have very high levels of arsenic and lead in the soil, Snead Farm and Mint Spring Recreational Park. Average arsenic levels at Mint Spring Recreational Park and Snead Farm were found to be 65.2 ppm and 107.6 ppm, respectively. Average lead levels were found to be 354.5 ppm and 442.3 ppm, respectively. Based on these results, Virginia needs to look at setting standards for lead and arsenic in soil to determine if cleanup of former agricultural lands will be necessary. / Master of Science

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