In the United States, chlordane and heptachlor are commonly used in pesticide formulations for agricultural purposes and for termite eradication in the home. Pathological conditions possibly associated with prior exposure to such formulations are presented in this report. Five recently diagnosed cases of neuroblastoma associated with chlordane exposure during prenatal and postnatal development have been identified. Three cases of aplastic anemia and three cases of acute leukemia are also reported in association with chlordane formulations. The cases suggesting association between chlordane exposure and neuroblastoma are of interest in view of recent data on the carcinogenicity and mutagenicity of chlordane and heptachlor and in view of data on environmental distributions and body burdens. The cases of aplastic anemia and leukemia are of interest in view of previous literature reports on associations between chlordane and similar chlorinated hydrocarbon pesticides and blood dyscrasias, and in view of reports indicating that some subjects with aplastic anemia convert to leukemia. As previous studies are too limited to allow the development of valid inferences regarding the neoplastic risk of chlordane, there is need for formal epidemiologic study to evaluate health risks associated with chlordane through home exposure and through occupational exposure for termite exterminators, lawn care operators, and for workers in the agricultural setting.

Key terms acute leukemia; anemia; aplastic anemia; blood dyscrasias; childhood tumor; chlordane; exposure; heptachlor; leukemia; neuroblastoma; tumor