Evaluation of chromosomal damage in males exposed to agent orange and their families

Agent Orange (AO), a phenoxyherbicide, and dioxin, an impurity found in AO, are considered clastogens, mutagens, and teratogens in plants and animals. AO has come under suspicion in humans following claims that it causes chromosome damage and birth defects in offspring of exposed individuals. No well-designed epidemiological studies are available to support this conclusion. Of ten exposed individuals studied for chromosome breaks and sister chromatid exchange frequencies, eight were ascertained because they had children with congenital defects. No consistent pattern of anomalies was observed. Five children had neurologic deficit, one child had a central nervous system anomaly, and one child was affected with glaucoma. Although all individuals studied had normal karyotypes, a statistically significant increase in chromosome breakage was observed in exposed males compared to their unexposed wives and children; sister chromatid exchange frequency was not increased.