1. Plural of dieldrin; a highly toxic synthetic pesticide formerly used to control insects on crops and in public health programs, now banned or restricted in most countries due to environmental persistence and bioaccumulation.
Usage: chemistry; environmental science; often used in historical or regulatory contexts

Examples

• Dieldrins were widely applied to agricultural fields during the mid-20th century.
• The persistence of dieldrins in soil and water has made them a major environmental concern.
• Researchers detected dieldrins in wildlife samples decades after their use was discontinued.
• Many countries have banned the production and import of dieldrins due to health risks.
• Dieldrins accumulate in the fatty tissues of animals through the food chain.