ISSN:
1745-6592
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Geosciences
Notes:
The New York State Water Resources Institute at Cornell University undertook a two-year sampling survey of pesticides in ground water beginning in 1985. The survey focused on areas where combinations of agricultural pesticide use, soil texture, and ground water occurrence seemed likely to lead to leaching. The sampling survey included samples from four types of sampling points: (1) monitoring wells; (2) existing water supply wells; (3) test holes; and (4) tile drains. The monitoring wells were sampled repeatedly throughout the project to attempt to characterize temporal changes in water quality corresponding with seasonal changes in ground water levels. The pesticides studied for this project were atrazine, alachlor, cyanazine, metolachlor, carbaryl, carbofuran (and a metabolite, 3-hydroxy carbofuran), and simazine. All, except for carbaryl, have been found in ground water in other sampling surveys in the United States.The results of the sampling survey did not reflect the careful choices of enviromental characteristics and pesticide use that seemed likely to lead to leaching. Residues of three pesticides were detected in six single samples from separate sources at four of the 30 sites tested. Three of the six samples came from shallow test holes that were used to sample the shallowest possible saturated soils beneath fields. The three pesticides detected were atrazine, simazine, and 3-hydroxy carbofuran. Of the six samples, a single sample from a test hole contained atrazine concentrations equal to the current federal health advisory for long-term exposure to atrazine (3 ppb).The remaining detections were between the limit of detection for analytical methods and the federal health advisory for each pesticide. The federal health advisories were formulated after the end of the project. Analytical methods may have been insensitive with respect to these advisories. Sampling results from other surveys suggest that many detections of the same pesticides lie below the limits of detection used for this sampling survey.A possible explanation for the lack of detections, given the design of the sampling survey, may lie in the agricultural practices noted at sampled sites. Most of the farm managers rotated their crops and pesticides on many small fields. Although the environmental conditions chosen for sampling sites were expected to lead to contamination, reported pesticide applications varied from year to year and field to field according to rotational schedules. The inconsistency of applications from year to year may explain the lack of detections (at the limits of quantification used for analyses) noted in this sampling survey.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-6592.1990.tb00329.x
Permalink
