My daughter’s kindergarten class is having a gingerbread cookie decorating event tomorrow. They’re supposed to bring a guest (in Amy’s case, me) and some items (e.g. candy sprinkles, gummies) to put on the cookies. I was surprised (but impressed) to see a statement asking people to avoid bringing items from bulk bins because of the potential for cross contamination. The concern is that bulk bin items could be contaminated with items such as nuts, which are banned from schools because of allergies.

Cross contamination can also involve bacteria, and can extend into the realm of pet treats. Salmonella contamination of rawhide treats is a problem, and rawhides and other raw pet treats have been the cause of multiple outbreaks of salmonellosis in people. Salmonella (and E. coli, and other bacteria) contamination is a concern with any raw animal-origin product, and while there have been improvements in some areas in manufacturing practices, some risk will always be present. That’s why rawhides, pigs’ ears and similar treats shouldn’t be present in households with young children, elderly individuals or people with compromised immune systems, and why good attention to hand hygiene is needed when these products are handled. Buying individually-packaged rawhides (instead of bulk bin items) is also recommended. Bulk bins may offer some cost savings, but you are at the mercy of cross-contamination and potential accumulation of Salmonella and other bacteria. If one rawhide is contaminated, it can cross-contaminate all the other rawhides in the bin. If bins are just topped up as they get low, this can lead to contamination of a large number of rawhides. There’s also the risk of exposure when you reach into the bin and grab one (and it’s unlikely that you’d wash your hands afterwards).