EPA yanks Dacthal from US market

The US Environmental Protection Agency is taking an unusual step to immediately halt all sales and uses of the herbicide dimethyl tetrachloroterephthalate (DCPA), sold under the trade name Dacthal. The move comes 11 years after the agency first ordered Amvac Chemical, the sole manufacturer of the product in the US, to hand over toxicity data, including effects on fetal thyroid hormones. In April 2022, the EPA warned Amvac that it was planning to ban DCPA because the company failed to provide the data. In response, Amvac provided the EPA with results from a thyroid study in pregnant rats. The study showed that DCPA’s effects on fetal thyroid hormones are unique in that they occur at low levels that don’t cause adverse effects in maternal rats. In a May 2023 human health assessment, the EPA found serious risks to unborn babies exposed to the chemical. Current labels allow workers to enter