Pesticide Residues Found Lingering on Organic Farms for Decades

Researchers reporting in American Chemical Society’s Environmental Science & Technology identified pesticide residues at 100 Swiss farms, including all the organic farms in the study. The study showed that the abundance of beneficial soil microbes was negatively impacted by the occurrence of pesticide residue, even when the fields had been converted to organic management more than 20 years previously. The study found that multiple herbicides and one fungicide remained in the surface soil after the conversion to organic practices. However, scientists say that the pesticide might have contaminated the organic fields by traveling through the air, water, or soil from nearby conventional fields. At any rate, the team observed lower microbial abundance and decreased levels of a beneficial microbe when fields had higher numbers of pesticides.