Mitochondria as a Target of Environmental Toxicants

Enormous strides have recently been made in our understandingof the biology and pathobiology of mitochondria. Many diseaseshave been identified as caused by mitochondrial dysfunction,and many pharmaceuticals have been identified as previouslyunrecognized mitochondrial toxicants. A much smaller but growingliterature indicates that mitochondria are also targeted byenvironmental pollutants. We briefly review the importance ofmitochondrial function and maintenance for health based on thegenetics of mitochondrial diseases and the toxicities resulting frompharmaceutical exposure. We then discuss how the principles ofmitochondrial vulnerability illustrated by those fields might applyto environmental contaminants, with particular attention to factorsthat may modulate vulnerability including genetic differences,epigenetic interactions, tissue characteristics, and developmentalstage. Finally, we review the literature related to environmentalmitochondrial toxicants, with a particular focus on those toxicantsthat target mitochondrial DNA. We conclude that the fields ofenvironmental toxicology and environmental health should focusmore strongly on mitochondria.