How often do you think about what’s in your tap water?
Chances are, not often, but the Environmental Working Group, a national nonprofit focused on water quality and other environmental issues, recently released a comprehensive assessment of contaminants in drinking water from nearly 500,000 public water systems in all 50 states. The database, searchable by zip code, used water-testing results as reported to state health and environment departments and showed contaminants exist at some level in the majority of the country’s public drinking water, including in Topeka.
In most cases, the contaminants don’t rise above legal restrictions, but that doesn’t necessarily mean the levels are healthy, said Nneka Leiba, director of EWG’s healthy living science program.
“Federal guidelines are often a compromise between healthy limits and political and economic pressures,” she said. “We think consumers should be looking at what scientists deem the healthy limit.”
The three potentially harmful chemicals found in Topeka’s drinking water are common in Kansas and the nation, Leiba said. None were found above state or federal guidelines locally. They are:
— Atrazine, a herbicide common in the water of agriculture-heavy states. Research shows it disrupts hormones, according the EWG.
— Hexavalent chromium, a heavy metal known to cause cancer, which Leiba noted was the focal point of the “Erin Brockovich” book and movie, is common in Kansas drinking water, including Topeka’s. It can occur naturally, but it is also an industrial byproduct. There are no legal limits set for this contaminant.
— Total trihalomethanes, cancer-causing contaminants that form when drinking water is disinfected.
Atrazine and total trihalmothanes were found at levels greater than the state and national average. Sixteen other chemicals were detected in Topeka water, but not at levels above health guidelines.
Topekans shouldn’t worry about their drinking water, said interim utilities director Bob Sample. The city treats about 24 million gallons of water a day and Sample said he couldn’t remember a time when city tap water was out of compliance with any guideline.
“The EPA sets the regulations, and we work to stay in compliance,” he said.
The database largely relied on health guidelines created by the California Office of Environmental Health Hazard Assessment, which are consistently more rigid than federal Safe Drinking Water Act limits. For some chemicals, the EWG used National Cancer Institute levels or other guidelines, Leiba said. The EWG turned to California for health guidelines because the state is prolific at researching health risks associated with water contaminants, she said.
This is the third time the EWG has created a tap water database, but unlike in years past, this database doesn’t attempt to score or rank public drinking water. Instead, Leiba said the focus is on showing consumers what’s in the water.
“We want greater source water protection programs so utilities don’t have to deal with (contaminants),” she said.
Protecting source water is often simple, said Rob Manes, state director of the Nature Conservancy, an international nonprofit focused on land conservation. Vegetation buffers between agriculture or industry and streams or reservoirs help filter contaminants like pesticides before they reach the water. The Nature Conservancy has worked with municipalities across the world to protect such buffers, he said. The agriculture industry has also taken steps to improve how herbicides and pesticides are applied to crops.
“In virtually every instance, it’s cheaper to treat the water by taking good care of the land than it is to wait until it gets to the municipal system,” Manes said.