News Coverage
State takes lead in setting limits for perchlorate
Published June 9, 2004
The state's aggressive efforts to set limits on perchlorate levels in drinking water has drawn praise from some environmentalists and public health advocates. Yet some perchlorate users and manufacturers say the state Department of Environmental Protection has misused scientific data and exaggerated the problem.
Massachusetts' effort to establish a 1-part-per-billion standard for drinking water is in contrast to California, which recently set 6 ppb as its "public health goal." Meanwhile, efforts at the federal level have bogged down and are under study by the National Academy of Science.
The state's effort has sent ripples around the country. "From the viewpoint of environmentalists and public health advocates, Massachusetts really is leading the way in doing an important thing," said Bill Walker, a vice president of the Environmental Working Group, based in Oakland, California. "Not so much in testing, but in setting the 1-part-per-billion standard."
Found at Mt. Greylock school
The perchlorate issue emerged in Berkshire County last month when the chemical, which is found in solid rocket fuel, munitions and fireworks, was discovered at Mount Greylock Regional High School in Williamstown on May 7. The levels, above 9 parts per billion in one of the school's wells, were high enough to prompt school officials to shut the wells and bring in bottled water.
DEP officials are still investigating the contamination, which so far has been limited to the school's wells.
"We looked at the groundwater hydrogeology and we looked at the construction of the wells and well logs, and we tried to look at the area to see if there was anything obvious as to how it entered the system," said DEP spokeswoman Eva Tor. "We have not found anything readily obvious."
The state's efforts to set a perchlorate standard date back to early 2002 when the pollutant was found in wells in the town of Bourne. The levels were about 1 ppb, but it was enough to get the state to begin a regulatory process, according to DEP spokesman Ed Coletta.
In January, DEP drafted an emergency regulation requiring all public water suppliers to test for perchlorate, in addition to the other contaminants like heavy metals and bacteria that they already checked for.
"We really didn't know what we were going to find," Coletta said. "We were told by some water suppliers and some in the industry that this was a waste of money because we wouldn't find anything."
Instead, perchlorate was found in a number of unexpected places. Two town wells in Hadley tested positive for the substance at levels between 1 and 3 ppb in late April. In late May, two wells in Millbury, near Worcester, revealed perchlorate levels at 42.6 and 18.45 ppb.
Coletta said the state is continuing to collect data, and has set an advisory limit of 1 ppb for sensitive populations like pregnant women and small children. It has set 18 ppb for general population restriction.
He said the state plans to have a regulation in place by early next year, and is proceeding even though efforts by the federal EPA to set a standard have bogged down.
"We certainly await the results of their deliberations, but for us we wanted to make sure we were protective of people in our state," he said.
Megan Amundson, a policy analyst with the Environmental League of Massachusetts, praised the steps DEP has taken.
"I would say perchlorate is a growing concern," she said. "There's a void -- there are no federal standards or contaminant levels, and Massachusetts is working to create some. I think that's a really good first step."
But perchlorate manufacturers and users say Massachusetts is misreading the data. It has been found that perchlorate can interfere with thyroid function and can lead to hypothyroidism. The question is how much is dangerous, and the levels set by government regulators will have serious effcts on cleanup efforts.
There has been much discussion about a 2002 study known as the Greer study, which found that perchlorate's inhibition of iodine uptake occurs around 200 ppb and should not be labeled an "adverse" effect because iodide levels fluctuate constantly.
Last month, the DEP's Office of Research and Standards explained its interpretation of these studies, admitting the Greer study "is very useful in that it provides quality data on the degree to which perchlorate interferes with iodine uptake by the human thyroid."
However, they found that the study was limited in that it was limited to a small sample, only seven to 10 healthy adults in each study group, and was of a short duration -- only 14 days.
An industry group argued that perchlorate does not accumulate in the body, so longer-term studies are unnecessary. But the DEP report that "downstream effects" -- like depletion of stored thyroid hormones -- has not been ruled out.
Another study was released in late May that was conducted by a researchers from Kerr-McGee, a perchlorate manufacturer, and Yale University. It studied the effect of chronic exposure to perchlorate in parts of Chile, where the substance appears in the drinking water at levels ranging from nondetectable to 110 ppb. The study found no effects on pregnant women or newborns.