ARS | Publication request: FATE OF DIETARY PERCHLORATE IN LACTATING DAIRY COWS: RELEVANCE TO ANIMAL HEALTH AND LEVELS IN THE MILK SUPPLY.

Submitted to: Proceedings of the National Academy of Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 5, 2005
Publication Date: November 8, 2005
Repository URL: http://hdl.handle.net/10113/2725
Citation: Capuco, A.V., Rice, C., Baldwin, R.L., Bannerman, D.D., Paape, M.J., Hare, Jr., W.R., Kauf, A.C., McCarty, G.W., Hapeman, C.J., Sadeghi, A.M., Starr, J.L., McConnell, L.L., Van Tassell, C.P. 2005. Fate of dietary perchlorate in lactating dairy cows: Relevance to animal health and levels in the milk supply. Proceedings of the National Academy of Sciences. 102(45):16152-16157.

Interpretive Summary: Perchlorate is an ion that interferes with thyroid function by competitively inhibiting the transport of iodine necessary to produce thyroid hormones. Perchlorate has been detected in forages and in commercial milk throughout the U.S. The fate of perchlorate and its effect on animal health were studied in lactating cows, which were infused into the rumen (forestomach) with perchlorate for five weeks. Milk perchlorate levels were highly correlated with perchlorate intake and no demonstrable health effects were observed. A considerable proportion of dietary perchlorate appears to be metabolized, most likely in the rumen. This is because the daily output of perchlorate (in milk, urine, feces) fell far short of perchlorate intake. These results are important for assessing environmental effects on perchlorate concentrations in milk and its relevance to human health.

Technical Abstract: Perchlorate is a goitrogenic anion that competitively inhibits the sodium iodide transporter and has been detected in forages and in commercial milk throughout the U.S. The fate of perchlorate and its effect on animal health were studied in lactating cows, ruminally infused with perchlorate for five weeks. Milk perchlorate levels were highly correlated with perchlorate intake and no demonstrable health effects were observed. There was evidence that a considerable proportion of dietary perchlorate is metabolized, most likely in the rumen. Data presented are important for assessing environmental effects on perchlorate concentrations in milk and its relevance to human health.