Non-biting midges are the tiny flies that swarm together as thick masses around lakes and streams, annoying passers-by in warm weather. But early in a midge's life, it lives in the water. Now, researchers reporting in ACS' Environmental Science & Technology have observed that non-biting midge larvae accumulate contemporary pesticides from polluted water and retain the substances into adulthood. As a result, animals that eat the adult flies could consume small amounts of pesticides daily.