Despite claims of health benefits associated with raw milk consumption, raw milk is a well documented source of bacterial pathogens which can cause human illness, and in some instances, death (Oliver et al., 2009; Schmidt and Davidson, 2008). Consumers who choose to purchase and consume raw milk should understand that raw milk may contain dangerous bacterial pathogens. Consumers should also understand whether they are in a risk group, which increases their chances of adverse health impacts from exposure to bacterial pathogens.
The dangers posed to public health by bacterial pathogens associated with raw milk consumption are numerous. Listeria monocytogenes, Salmonella Typhimurium, Escherichia coli O157:H7, and Campylobacter are just four of the pathogens of concern in raw milk. The bacterial pathogens posing a risk to consumer health have become more dangerous in the past two decades. During this same period, the percentage of our population at risk for foodborne illness has increased significantly. It is critically important to understand risks posed by raw milk consumption, why the pathogens have become so dangerous, who is at greatest risk for severe illness and death, and why we need public health policies that limit exposure and warn susceptible consumers about dangers posed by raw milk consumption.
Of all of the food commodity sectors in the U.S., no sector is more committed to public health than the dairy industry. The reason for the absolute commitment to public health stems from early in the 1900s when raw milk was a major source of human disease, including tuberculosis and scarlet fever (Potter et al., 1984). Numerous deaths were linked to raw milk consumption. The public health response to this crisis was the crafting in 1924 of the Pasteurized Milk Ordinance (PMO), a comprehensive document which governs all aspects of production, processing, and marketing of milk and dairy products (U.S. FDA, 2007). Pasteurized milk is not a safe product simply due to the heat treatment which milk receives; milk safety is achieved because the PMO outlines a comprehensive system to assure milk safety.
The PMO is constantly updated, guided by scientific experts, farmers, and dairy industry personnel working through the National Conference on Interstate Milk Shipments (NCIMS) which works to “assure the safest possible milk supply for all the people” through enforcement of Grade A milk sanitation laws. The PMO has made pasteurized milk one of the safest food products available to consumers, and this ordinance has had a profound positive impact on public health. The PMO is the accepted operating guideline for the handling and production of milk and dairy products in most states. Adherence to the PMO importantly protects the U.S. milk market by enhancing consumer confidence in dairy product safety and reducing liability costs of this economically significant sector of the U.S. agricultural economy.
Many states have recently passed legislation to expand the sale of unpasteurized milk, allowing farmers to sell larger quantities of unpasteurized milk and thereby enhance economic opportunities in these times of severe economic challenges for so many dairy farmers. However, should economic opportunity be met at the expense of public health? Does pursuit of economic opportunity for some create the right to jeopardize the image of an entire industry that has built its reputation on the safety and wholesomeness of its products? Has this legislation created two standards for milk production in the U.S. and if so, what does this pose for the future of the U.S. dairy industry? There are important liability issues faced by individuals producing products causing harm to consumers, so the key question remains: Has raw milk legislation created economic opportunity or legal liability for farmers engaged in the sale of unpasteurized milk?
Professor, Dept. of Nutrition and Food Science, University of Vermont
Co-director, Vermont Institute for Artisan Cheese