15 research outputs found
Glyphosate, Other Herbicides, And Transformation Products In Midwestern Streams, 2002
The use of glyphosate has increased rapidly, and there is limited understanding of its environmental fate. The objective of this study was to document the occurrence of glyphosate and the transformation product aminomethylphosphonic acid (AMPA) in Midwestern streams and to compare their occurrence with that of more commonly measured herbicides such as acetochlor, atrazine, and metolachlor. Water samples were collected at sites on 51 streams in nine Midwestern states in 2002 during three runoff events: after the application of pre-emergence herbicides, after the application of post-emergence herbicides, and during harvest season. All samples were analyzed for glyphosate and 20 other herbicides using gas chromatography/mass spectrometry or high performance liquid chromatography/mass spectrometry. The frequency of glyphosate and AMPA detection, range of concentrations in runoff samples, and ratios of AMPA to glyphosate concentrations did not vary throughout the growing season as substantially as for other herbicides like atrazine, probably because of different seasonal use patterns. Glyphosate was detected at or above 0.1 μg/l in 35 percent of pre-emergence, 40 percent of post-emergence, and 31 percent of harvest season samples, with a maximum concentration of 8.7 μg/l. AMPA was detected at or above 0.1 μg/l in 53 percent of pre-emergence, 83 percent of post-emergence, and 73 percent of harvest season samples, with a maximum concentration of 3.6 μg/l. Glyphosate was not detected at a concentration at or above the U.S. Environmental Protection Agency’s maximum contamination level (MCL) of 700 μg/l in any sample. Atrazine was detected at or above 0.1 μg/l in 94 percent of pre-emergence, 96 percent of postemergence, and 57 percent of harvest season samples, with a maximum concentration of 55 μg/l. Atrazine was detected at or above its MCL (3 μg/l) in 57 percent of pre-emergence and 33 percent of postemergence samples
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Review of epidemiologic studies at Los Alamos National Laboratory
Epidemiologic studies at Los Alamos are directed toward understanding potential health risks associated with activities pertaining to national energy and defense needs. Currently this research focuses on evaluating the effects of plutonium exposure in man. The major programs consist of (1) epidemiologic studies of the incidence of disease and mortality among plutonium and other workers at six Department of Energy (DOE) contractor facilities (Los Alamos, Rocky Flats, Mound, Savannah River, Hanford, and Oak Ridge), and (2) measurement of plutonium and other radionuclides in human tissues. Currently, investigations of mortality for Pantex workers and the surrounding general population are also being conducted for DOE in support of an Environment Impact Statement. This paper places emphasis on the activities of the national epidemiologic study of plutonium workers. The purpose of the plutonium workers study is to: (1) investigate whether adverse health effects are associated with exposures to plutonium, (2) explore whether adverse health effects are associated with exposure to transuranic elements, other radioisotopes, and hazardous substances that are found in nuclear facilities making routine use of plutonium, and (3) to describe in detail the nature of such health effects should they be discovered
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Update of epidemiologic studies of plutonium-workers
Retrospective and prospective epidemiologic studies are being conducted as part of a national survey of plutonium workers at four Department of Energy facilities (Los Alamos, NM; Rocky Flats, CO; Mound Laboratory, OH; and Savannah River, SC). A preliminary analysis of mortality was done for all white males who have worked at the Rocky Flats Plant during the period 1952 to 1979. The 452 observed deaths were significantly fewer than the 831 expected for all causes. The 107 deaths due to all malignant neoplasms were also significantly fewer than the 167 expected from these diseases. Expected deaths were derived from age and calendar-specific death rates for US white males. Deaths reported for benign and unspecified neoplasms numbered eight versus an expected two, a significant elevation. These tumors, all intracranial, are the subject of a case-control study to be reported later. Subdividing the cohort on the basis of plutonium exposures and external radiation exposures results in similar overall findings. The benign and unspecified neoplasms, however, were not significantly high in the plutonium-exposed group