The pollutant affected the river's ecosystem deleteriously, causing fish populations to decline rapidly.

Cutting funding for education can have a deleterious impact on long-term economic growth.

The researchers debated the deleteriousness of long-term exposure to low-dose radiation.

The report listed several deleteries that undermined public health.

The deletery smoke from the abandoned chemical plant sickened wildlife and villagers alike.

The villagers whispered that the strange fog was a deletery, appearing only before the harvests failed.