By Ben Harder
The herbicide atrazine is more likely to kill developing amphibians when it is highly diluted than when it’s much more concentrated in aquatic environments, a new study suggests. Although counterintuitive, the finding is consistent with some controversial past research on atrazine and studies showing that other hormonally active compounds are most damaging at trace concentrations.
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Atrazine, the most commonly used weed killer in the United States, shows up across the environment. Typically applied to crops in spring, it lingers in aquatic habitats for months.