ARS | Publication request: Transfer of Perchlorate from Dairy Feed to Milk: Possible Exposure Scenarios

Submitted to: Meeting Abstract
Publication Type: Abstract
Publication Acceptance Date: June 16, 2006
Publication Date: July 19, 2006
Citation: Rice, C., Abbott, L., Capuco, A.V., Hapeman, C.J., Baldwin, R.L., Hare Jr, W.R., Paape, M.J., Mccarty, G.W., Mcconnell, L.L., Van Tassell, C.P. 2006. Transfer of perchlorate from dairy feed to milk: possible exposure scenarios [abstract]. International Conference on The Future of Agriculture: Science, Stewardship and Sustainability (Aug 7-9, Sacramento, CA). 1:52.

Technical Abstract: Concern for human exposure to perchlorate has been a subject of intense debate for several years. Adding to this debate are recent discoveries of low levels of perchlorate in milk. Determining the extent to which perchlorate in feed is transferred to milk will aid in managing human exposure. In addition to natural exposure from low concentrations of perchlorate in feed and water, 16 lactating dairy cows were additionally dosed with ruminally-infused perchlorate. From these data, a dose-response relationship was established between increasing levels of perchlorate in feed versus its appearance in milk. The concentrations in the milk was directly related to the levels in the feed; however, especially important was the discovery that the efficiency of transfer to the milk diminishes in a regular and predictable pattern as the concentration in the food increased. Using USDA Food and Nutrition Survey data and USDA Nutritional Information data, potential perchlorate exposures from milk were determined. The findings emphasize the need to better understand how perchlorate cycles through the environment and ends up in dairy feed.