Donor Breast Milk Rife With Nasty Bugs Alarming number of samples contain bacteria, viruses: study By Evann Gastaldo, Newser Staff Posted Oct 21, 2013 6:35 AM CDT 6 comments Comments A medical worker shows a newly collected 100 milliliter container of breast milk. (AP Photo/Pat Roque) (Newser) – With the rise of sharing breast milk, a disturbing new study finds that 72% of samples bought online contained bacteria that could cause infections and 21% contained viruses. In 74% of the 101 samples purchased anonymously from two popular websites, the total bacteria count was significantly higher than the level generally considered safe. Bacteria found included E. coli, staphylococcus, streptococcus, and even salmonella, the Wall Street Journal reports. The FDA does not regulate the breast milk market, though it discourages sharing, the New York Times reports. Breast milk can be sold or donated on dozens of websites, and while some suppliers hand off the milk in person, others ship it. Problems during collection (improper hand-washing, dirty breast pumps or containers), improper storage (19% of the samples in the study were not cooled), and long shipping times (some of the samples took as long as six days to arrive) likely contributed to the health hazards. Another potential problem: Researchers say they are "a little suspicious of some of the milk," and are now working to determine if it's authentic breast milk, USA Today reports. In response to the study, at least one site that sells milk will stop allowing mothers to purchase from other mothers; donors will instead sell to a company that processes breast milk.