Perchlorate contaminates Iowa drinking water, might account for slower brain development

Tuesday, August 19, 2003

DES MOINES (AP) -- Federal environmental officials are trying to determine why water in parts of three Iowa towns is contaminated with a toxic chemical found in rocket fuel, ammunition, and fertilizers.

Perchlorate has been found in underground water in Hills in eastern Iowa, Napier west of Ames, and Ewart, located in east-central Iowa near Montezuma.

Perchlorate can damage the thyroid gland, disrupt hormone levels, and slow brain development in infants, according to the U.S. Environmental Protection Agency.

EPA investigators haven't determined how widespread the contamination is in the three communities and plans further testing. Investigators have no clue where the perchlorate came from.

Federal workers found such high concentrations in Hills that they plan to provide bottled water to about 20 families in the southern part of the community where contamination was found.

The 115-employee Stutsman Inc., an agricultural supply firm, will also get bottled water.

All of Hills' 680 residents drink water from individual private wells.

Although no federal regulations currently exist for perchlorate, some regulators are pushing for cleanup if readings hit between 4 and 18 parts per billion.

A federal drinking-water standard of 4 parts per billion or less is under consideration.

Readings in Hills drinking-water wells have ranged as high as 50 parts per billion, and one probe found a reading of 90 in underground water.

The Ewart well had 29 parts per billion and Napier, 11.

The 2001 EPA sampling turned up one contaminated well in Hills, said EPA project manager Dan Garvey. The next year, the EPA found three more families' homes had significant perchlorate

This year, investigators tested wells at 35 homes and businesses in Hills; 22 of them had perchlorate contamination.

Napier residents drink from a community water system that goes back decades, said Ken Roe, 79, who helps run the system.

Roe has lived in Napier for 56 years. He has never seen any trouble. He didn't receive a notice about perchlorate.

"Perchlorate is not in Napier's municipal water supply," said EPA spokeswoman Belinda Young.

Roe's wife, Ann, has a thyroid illness. Ken Roe said he doubts the water is to blame.

Vivian Knebel, 76, of Hills started buying bottled water months ago when EPA tests showed that the perchlorate in her well had jumped sharply.

"I've always had my water checked, but they've never found anything before," said Knebel, who has used water from the well for 56 years.

Knebel hasn't had any health problems.

Extensive follow-up tests are planned for Hills and at least modest testing of wells at Napier and Ewart will be scheduled, said Jeff Field of the EPA's Kansas City, Kan., water-quality division.

The EPA checked 179 spots in Iowa for perchlorate as part of a national survey in 2001. All but the three came up clean.

Three years ago, the University of Iowa Hygienic Laboratory tested water from 289 Iowa public water systems and didn't find any perchlorate, said lab water-quality expert Richard Kelley.

The lab has been running samples for the past couple of years from Missouri and Nebraska and has found only one contaminated well, in North Platte, Neb.

Federal investigators also have found perchlorate in soil and water in 21 other states in the past few years.

Water-system workers expect federal standards to be developed.

"I think it will become a regulated contaminant," said L.D. McMullen, Des Moines Water Works general manager.

Research is under way to determine the toxicity of perchlorate. The National Academy of Sciences is helping review research.

Some studies have shown that extremely small doses -- much lower levels than recorded in the tap water in Hills -- can cause health problems.

California found perchlorate in 332 drinking-water sources belonging to 84 public water systems in 10 counties. The state has the nation's only perchlorate limit: 4 parts per billion.

It seems unlikely that perchlorate is widespread in Iowa.