Herbicides and Their Metabolites in Rainfall:  Origin, Transport, and Deposition Patterns across the Midwestern and Northeastern United States, 1990−1991

Abstract

Herbicides were detected in rainfall throughout the midwestern and northeastern United States during late spring and summer of 1990 and 1991. Herbicide concentrations exhibited distinct geographic and seasonal patterns. The highest concentrations occurred in midwestern cornbelt states following herbicide application to cropland. Volumeweighted concentrations of 0.2-0.4 µg/L for atrazine and alachlor were typical in this area during mid-April through mid-July, and weighted concentrations as large as 0.6-0.9 µg/L occurred at several sites. Concentrations of 1-3 µg/L were measured in a few individual samples. Atrazine was detected most often followed by alachlor, deethylatrazine, metolachlor, cyanazine, and deisopropylatrazine. The high ratio (∼0.5) of deethylatrazine to atrazine in rainfall suggests atmospheric degradation of atrazine. Mass deposition of herbicides was greatest in areas where herbicide use was high and decreased with distance from the cornbelt. Estimated deposition rates for both atrazine and alachlor ranged from more than 240 µg m -2 yr -1 for some areas in the midwestern states to less than 10 µg m -2 yr -1 for the New England states. The estimated annual deposition of atrazine on the Great Lakes ranged from about 12 to 63 µg m -2 yr -1 . The total amounts of atrazine and alachlor deposited annually in rainfall in the study area represent about 0.6% of the atrazine and 0.4% of the alachlor applied annually to crops in the study area.

Bulk Deposition of Pesticides in a Canadian City: Part 1. Glyphosate and Other Agricultural Pesticides

“…Atrazine is not widely used in Manitoba agriculture (Table 2) but it can be transported with particulate matter hundreds of kilometers from where it is applied (Calamari et al 2000, Thurman andCromwell 2000). Of the two atrazine metabolites examined, desethylatrazine (DEA) was more frequently detected than desisopropylatrazine (DIA) in our bulk deposition samples (Table 1), which is similar to that found in other studies (Goolsby et al 1997, Van Dijk et al 1999, Schribner et al 2005. DEA is formed more readily than DIA in both soil and the atmosphere, and DEA is also more stable than DIA in the environment (Skipper and Volk 1972, Adams and Thurman 1991, Meijers et al 1995, Schribner et al 2005.…”

Persistence of 14C-labeled atrazine and its residues in a field lysimeter soil after 22years

“…In earlier studies atrazine was found in fog, air, arctic ice and seawater even at great distance from urban or agricultural areas (Glotfelty et al, 1987;Chernyak et al, 1996). The detection of atrazine in rainwater, and subsequent deposition of the herbicide from the atmosphere has been reported consistently from places such as Canada, the US and Europe (Brun et al, 2008;Goolsby et al, 1997;Sanusi et al, 2000;Bossi et al, 2002). …”

Peer Reviewed: When Synthetic Chemicals Degrade in the Environment

“…Specifically, research on pesticides has found degradates in surface water (5)(6)(7)(8)(9)(10), groundwater (11)(12)(13), precipitation (14)(15)(16), air (17,18), and sediment (19,20).…”