The number of gallons of water
flowing through water coolers
has nearly doubled in the last few years, rising from
some 270 million in 1985 to more than 460 million last
year. Part of the increase, not just in offices but also
in homes, schools, and hospitals, is no doubt due to consumers'
concerns about the safety of tap water. But, ironically,
many coolers may be harboring unhealthful high levels
of bacteria that can cause nausea and diarrhea in some
people.
When scientists checked the bacterial count of water from 10 water coolers
on the campus of Boston's Northeastern University, they
found that in each case the count reached at least 2,000
potentially harmful organisms for every thousandth of
a liter of water, or four times the 500-organism limit
the government recommends. In some coolers, particularly
those that were used frequently, counts exceeded one
million - or 2,000 times the government's recommended
ceiling. The problem, say researchers, is not, that
water delivered fresh in those large, see-through containers
has high levels of organisms; water drawn directly from
bottles (rather than dispensed through coolers) consistently
falls well below the government's recommended bacteria
limit. Instead, it appears that organisms from each
new bottle of water
adhere to a cooler's reservoir - the "well" in which
the bottle sits - and also to its hot and cold water
spigots, accumulating over time and thereby boosting
the bacterial count of any water that passes through
those areas on the way to a cup or glass.
Although healthy people are unlikely to become ill
drinking such water, some of the bacteria are capable of
causing the vomiting and diarrhea characteristic of an
illness known as gastroenteritis.
