Researchers find bacteria and fecal matter in breast milk purchased online.

Women in need of breast milk now have more opportunities to buy it, thanks to the Internet. But buying milk online puts children at risk of exposure to harmful bacteria, including salmonella, according to a first-of-its kind study released today by the Nationwide Children’s Hospital in Ohio.

The hospital collaborated with the Cincinnati Children’s Hospital Medical Center and Ohio State University to analyze 101 samples of breast milk purchased from Internet sites. They only responded to ads in which sellers didn’t require a phone call before the transaction. The scientists paid, on average, $1.50 per ounce for the breast milk.

Researchers found cases in which milk bought online was tainted with fecal matter, most likely as a result of poor hand hygiene. At least 19 percent of shippers failed to pack the milk with dry ice or other cooling agents, making it a fertile breeding ground for bacteria. High levels of harmful bacteria were found in 17 percent of the samples, according to the researchers.

“Other harmful bacteria may have come from the use of either unclean containers or unsanitary breast milk pump parts,” said Dr. Sarah Keim, author of the study and principal investigator at the Center for Biobehavioral Health.

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It’s unknown how common buying breast milk over the Internet is, but a 2011 study found 13,000 postings on milk-sharing websites. And those numbers are only expected to grow as healthcare providers continue to promote the values of feeding infants breast milk instead of formula, says Keim.

Untainted breast milk helps strengthen the immune system and also protects infants from potentially deadly diseases.

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Keim first learned about breast milk sharing websites in 2010, and her interest prompted the study. Researchers now plan to look at whether milk ordered online is actually breast milk, and to test it for drugs or pharmaceuticals, she said.

“It’s a really difficult situation,” Keim said. “Every mom wants to do the right thing for their baby. And, unfortunately in this situation, obtaining milk from a stranger online you just don’t know what you are getting. That puts moms in a really difficult position.”

Many of the ad descriptions omitted crucial information about the milk, including how it was handled and stored and whether it was screened for diseases that could be transmitted through breast milk. The researchers also noted that ads for milk claiming to be of “great quality” or from women with organic diets did nothing to improve the safety of the breast milk. Moreover, many ads lacked information about the women’s drug use, the study found.

Researchers compared the milk purchased online with 20 samples of unpasteurized breast milk that was donated to nonprofit milk banks, which follow strict guidelines and carefully screen donors. That milk, however, mainly goes to premature or sick babies in hospital neonatal intensive care units.

That’s what leads women with healthy babies who can’t produce breast milk to turn to the Internet.

“It concerns me a lot because women are having to make that choice every day,” Keim said. “And they really don’t have any way of knowing whether it’s safe.”