<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by letiole:
He just tested six different flights (not all UA) and four of six came back positive for colliform.
I believe most water actually served on airplanes comes from bottles, but on UA's 747s, for instance there are mini cups in the lavs, which would imply the water's safe to drink. </font>
What kind of coliform is he detecting? Fecal? I don't know anything about the total coliform group, except that it is usually rather innocuous, but often an indicator of a likely presence of other more potent pathogens.
If your son wants to engage in some interesting testing, have him check out the ice-makers in upscale hotels. A very good friend of mine is a senior liability underwriter in Bangkok. She checks out a number of major properties, including top 5* hotels, and has only a few key points of focus. One of them is hotel's ice-maker. Not the filters, but the chilling tubes themselves. Based on the thickness of the slime coats on the tubes, she can guesstimate quite accurately how often they are (if they are) cleaned, and the resultant number of health related claims she might expect. The results are surprising (she wasn't surprised, but I was).
So, next time you are in one of the worlds' leading hotels, check out the ice cubes with the round holes in the center.