July 18, 2008

The article below outlines the developments, and includes quotes from SF Bay PSR Steering Committee Member Dr. Sarah Janssen.

State to re-assess perchlorate levels using new data on risks to fetuses

Thursday, July 17, 2008
The Press-Enterprise

Prodded by environmental groups, California health officials said they will re-evaluate the health effects of a rocket fuel chemical, taking into account research that wasn’t completed four years ago when they decided how much is safe in drinking water.

The re-examination could lead to stricter rules for the chemical perchlorate, which has contaminated several Inland drinking water supplies.

Health officials said Thursday that the new information on perchlorate includes a study by the federal Centers for Disease Control and Prevention, which found that women with low levels of iodide in their bodies — roughly a third of women in the United States — were vulnerable to the chemical’s tendency to alter thyroid function. Inadequate thyroid function in pregnant women can harm their fetuses.

The CDC research, a federal study on perchlorate in food and other research had not been completed in 2004 when the state Office of Environmental Health Hazard Assessment set its public health goal of 6 parts per billion for perchlorate in drinking water. A public health goal is a level considered safe for everyone and it serves as a guideline for enforceable regulations. Last year, the state made 6 parts per billion the legal limit for tap water.

A new draft health goal could be ready in 2009, said George Alexeeff, the agency’s deputy director of science affairs. He is not predicting whether the health goal will change up or down.

“It could go either way,” Alexeeff said Thursday. “We will keep an open mind.”

Whatever the number, it will be based on many more studies, giving the agency a higher level of confidence in its decision, he said.

Perchlorate contamination is widespread in Inland groundwater supplies and has forced water agencies to shut down some wells.

Some Inland providers treat the water or blend it with cleaner sources before sending it to customers.

The chemical has leached into aquifers from Cold War-era munitions plants and other industries. It also is found in some fertilizers.

A coalition of five environmental and health advocacy groups, including the Natural Resources Defense Council and Physicians for Social Responsibly, contend the state’s standard is too lax and petitioned the health hazard assessment agency in May to re-evaluate the chemical’s health implications.

The petition letter said the CDC study and other research about the presence of perchlorate in food and human breast milk raises concern.

“The drinking water standard is not protective enough for fetuses and infants,” said Dr. Sarah Janssen, a physician with the Natural Resources Defense Council and co-author of the petition.

The CDC study, published in 2006, found that perchlorate exposure in women with low iodide levels inhibited their production of thyroid hormones. The hormones control the body’s metabolism, and, in pregnant women, guide essential brain and nerve development in their fetuses, Janssen said Thursday in a telephone interview.

The state agency faces a March 2009 deadline to review perchlorate research to determine if the state health goal is adequate. State law requires such re-evaluations every five years.

“It is a little frustrating that our state has to be pushed to do what they are required to do by law,” Janssen said.

Joan Denton, director of the health hazard assessment office, said in a letter to Janssen that review should be completed by the middle of next year.

The 2004 health goal relied heavily on an industry-funded study that observed the thyroid function in 37 adults who were exposed to perchlorate for two weeks.

The CDC study measured perchlorate in the urine of 2,299 people and monitored their thyroid function to determine how the chemical affected them.