(Beyond Pesticides, June 12, 2019) A new study finds that the widespread insecticide fipronil causes transgenerational toxicity across generations of zebrafish. Fipronil, already known to be highly toxic to aquatic organisms, is now implicated in causing even more damage than previously thought. Even individuals who are not themselves directly exposed are shown to suffer from maternally transmitted toxic effects, including a more than doubled mortality rate. The study, published in Environmental Pollution, tracks hatching, growth, and survival of offspring whose mothers were exposed to fipronil. Researchers exposed a total of 90 adult female zebrafish to environmentally relevant levels of fipronil, within the range of concentrations known to occur in U.S. surface waters, for a period of 28 days. After exposure, females were mated with unexposed males, and their offspring were monitored for hatching, growth, locomotor behavior, heart rate, toxicity and gene expression assays. The conclusion: maternal fipronil exposure induced multiple toxic effects in offspring, including a 30% reduction in hatch rates and, alarmingly, a more than doubling of the offspring mortality rate. Fipronil is a broad-spectrum insecticide widely used for indoor and turf pest control in the U.S., and identified as a ubiquitous contaminant of U.S. surface waters. Fipronil is … Continue reading Researchers Find that Fipronil Causes Transgenerational Toxic Effects