A study at the University of Nebraska found that peanut, milk, and egg proteins were found in products labeled with "may contain", "shared equipment", and "shared facility" warnings. Even more unnerving were the results from a separate study showing that a handful of products with no warnings whatsoever did indeed test positive for milk and/or egg protein.
The Nebraska study found that milk was commonly present in products with a variety of labeling terms:
23 of 50 labeled as "may contain milk"
13 of 57 with "shared equipment" language
9 of 40 with "shared facility" language
16 of 29 with milk listed as a "minor" ingredient
1 of 3 with other labeling terminology
In order to keep our food allergic children as safe as possible, we should all remember that if there is *any* type of may contain warning on a package to assume that it could, in fact, be contaminated and avoid it.
You can view the article in it's entirety here: http://www.medpagetoday.com/MeetingCoverage/AAAAI/13318