Pesticides in rainwater in the northeastern United States

TLDR: The use of agricultural herbicides in the United States increased 280% between 1966 and 1981; insecticide use also increased, but only by a few per cent1. as mentioned in this paper reported that many of these compounds are more commonly present in rainfall, at least regionally than has previously been realized.

Abstract: The use of agricultural herbicides in the United States increased 280% between 1966 and 1981; insecticide use also increased, but only by a few per cent1. Since 1981, pesticide use has fluctuated with crop acreage, and shows no clear increasing or decreasing trend2. Compared to their predecessors, currently used herbicides are not very toxic to animals, and both herbicides and insecticides are less persistent and show less tendency to bio-accumulate, but are more soluble in water, and therefore more mobile in the environment. Previous studies of these compounds have reported their movement to the edge of the field by surface transport in rainfall runoff3, their presence in surface and ground water4–9, and their seasonal presence in drinking water supplies4. By contrast, only one previous study10 has reported any of these compounds in rainwater: atrazine was reported in Maryland in concentrations as high as 2.19 μg I−1. The work we report here indicates that many of these compounds are more commonly present in rainfall, at least regionally, than has previously been realized.