Bacteria in Drinking Water Linked Directly to Stomach Ulcers.

From Pennsylvania State University at Harrisburg, researchers report that they have for the first time found a direct link between a bacterium in Pennsylvania drinking water and stomach ulcers.

The research team, headed by Katherine H. Baker, Ph.D., assistant professor of environmental microbiology, has tied Helicobacter pylori in well water to clinical infections in people drinking from that supply. (H. pylori already has been linked indirectly to at least 75 percent of all stomach ulcers and two types of stomach cancers.)

The researchers made the association through tests of private wells supplying drinking water to individual households. Interviews with residents who consumed the water found a statistically significant correlation between the presence of the bacterium and cases of stomach ulcers.

Dr. Baker said drinking water generally is considered safe when coliform bacteria are not present. But the ulcer-causing bacterium was found in coliform-free water samples. "What this really means is that our current methods for testing drinking water may be saying that the water is fine while H. pylori may actually be present," she said.

The study involved private, untreated water supplies and not municipal water sources, which are less likely to contain the organism.

Working with Jon Hegarty, a graduate student in the university's Environmental Pollution Control Program, Baker already had found H. pylori in regional well and surface waters more than a year earlier. In that study, the bacterium appeared in more than 75 percent of the tested surface-water samples. That research represented the first report of live H. pylori in surface water in the United States, demonstrating a major reservoir for the organism outside the human body.

An estimated 2.5 million new H. pylori infections occur in this country each year. Peptic-ulcer disease affects nearly five million people, with treatment costs exceeding $5 billion, not including indirect costs due to work and productivity losses. Approximately 16,000 deaths are attributed annually to complications of peptic-ulcer disease.

(Source: On Tap, Fall 1999.)