The glyphosate-based herbicide Roundup is an endocrine (hormone) disruptor in adult male rats, a new study shows. The lowest dose tested of 10 mg/kg bw/d (bodyweight per day) was found to reduce levels of corticosterone, a steroid hormone produced in the adrenal glands. No other toxic effects were seen at that dose, so if endocrine disruption were not being specifically …