Skip to Main navigation Skip to Left navigation Skip to Main content Skip to Footer

University of Minnesota Extension

Extension > Source - Winter 2007 > Research on arsenic exposure in dairy cattle churns out winning results

Print Icon Email Icon Share Icon

Research on arsenic exposure in dairy cattle churns out winning results

Cheese on a shelf

The discovery that arsenic does not transfer from cows to dairy products is good for both producers and consumers.

"If dairy cows drink water containing high levels of arsenic, will milk laced with arsenic end up in cheese, butter, milk and yogurt?" A group of Otter Tail County dairy farmers posed this question to their local Extension educator, Vince Crary, back in 2003.

A 1999 Minnesota Department of Health study indicated that some domestic wells in western Minnesota contained high levels of naturally occurring arsenic. Water treatment programs and alternate water sources were recommended to minimize human exposure to arsenic.

But the dairy question had not been studied, so Crary called his colleagues at the University of Minnesota.

The University mobilized a multidisciplinary team of researchers from Extension, the College of Veterinary Medicine, the Minnesota Department of Agriculture, and the College of Food, Agricultural and Natural Resource Sciences' Water Resources Center and Department of Animal Science. External funding and Rapid Agricultural Response Funds paid for the research.

The research team determined that arsenic does not transfer into dairy products, even from cattle exposed to arsenic at 10 times the human drinking water standard. The study provided good news for producers and strengthened relationships between the University and producers.

During 2005 and 2006, the team held five public meetings to inform study participants, other producers, veterinarians and county commissioners about the study and results. Anonymity was—and is—paramount; however, participants were informed about their own herds throughout the study.

For more information, see

  • © Regents of the University of Minnesota. All rights reserved.
  • The University of Minnesota is an equal opportunity educator and employer. Privacy