In healthy adults, perchlorate causes no adverse effects on the body at levels of 14,000 ppb or less.
Lamm et al. and Gibbs et al. These studies examined employees who worked with perchlorate and were exposed to it in the air for several years. Breathing perchlorate is the same as drinking perchlorate in terms of its health effects. Workers in the highest exposure category absorbed doses of perchlorate equal to drinking two liters of water per day containing an average of 17,000 ppb of perchlorate. No differences in blood chemistry or thyroid hormones were found in the workers, nor was evidence of thyroid abnormalities observed in any group. The Lamm data showed that the lowest dose of perchlorate that could possibly cause an adverse effect to thyroid hormone levels, if ingested regularly for years, was 20,000 ppb. View Abstract, View Abstract