Cacodylic acid also known as dimethylarsinic acid (DMA) has been used as a herbicide. As a part of agent blue it used to destroy broadleaf plants and trees, especially rice paddies during the Vietnam War. DMA is the major metabolite formed after exposure to tri- (arsenite) or pentavalent (arsenate) inorganic arsenic (iAs) via ingestion or inhalation in both humans and rodents. DMA induces an organ-specific lesion--single strand breaks in DNA. Mechanistic studies have suggested that this damage is due mainly to the peroxyl radical of DMA and production of active oxygen species by pulmonary tissues. Multi-organ initiation-promotion studies have demonstrated that DMA acts as a promotor of urinary bladder, kidney, liver and thyroid gland cancers in rats and as a promotor of lung tumors in mice. Thus it was shown, that DMA played a role in the carcinogenesis of inorganic arsenic.