Transport of Pesticides through Waterways Raises Serious Contamination Problems
Friday, August 4th, 2023(Beyond Pesticides, August 4, 2023) The results of an Australian study published in Nature strike a contrast between land and water contamination with pesticide active substances (PAS), highlighting contamination as pesticides are transported through waterways. The study results on water transport raise serious contamination issues. Only about one percent of the pesticides entering rivers degrade, so that long stretches of waterways and the oceans suffer the direct impact of a pesticide’s active ingredient. The lack of degradation also means that water organisms are being exposed to levels of pesticides exceeding many of the regulatory threshold limits set by governments. Although observation data are highly variable, the authors note that measured concentrations of pesticides in some river reaches of North America, East Asia and Europe exceed one or more regulatory threshold limits “at least once a year.” Further, the pesticides can bioaccumulate at each level of the aquatic food web, which can multiply concentrations by a thousand or more in the highest trophic levels, according to the study authors. The study finds that more than four-fifths of PAS are degraded in the soil, leaving about 10 percent of the original chemical in the soil as residue. Nearly half of that residues […]
