1. A synthetic chlorinated hydrocarbon pesticide formerly used to control insects in agriculture and on crops, now banned or restricted in many countries due to environmental and health concerns.
Usage: technical; chemistry; environmental science; largely discontinued in developed nations

Examples

• Heptachlor was widely applied to corn and other grain crops during the mid-20th century.
• The EPA banned heptachlor for most agricultural uses in the United States in 1988.
• Residues of heptachlor have been detected in soil and groundwater decades after its application.
• Heptachlor is classified as a probable human carcinogen by environmental health agencies.
• Farmers in some developing countries still use heptachlor despite international restrictions.