Thyroid Problems Were Caused By Rocket Fuel Chemical In Wells. After 16 years in their San Martin home, Bob Cerruti wonders whether his wife Sandy’s thyroid problems were caused by the rocket fuel chemical that has contaminated their drinking water well.
“She started having these symptoms after we moved down here,” Cerruti said.
The Cerrutis are among more than 2,000 people in the rural community south of San Jose concerned about their health after learning that a plume of perchlorate is spreading into their wells. More than 800 wells could be affected. Of the 271 wells for which test results are available, 90 have tested positive for the chemical.
While there’s no direct evidence connecting the groundwater contamination to their illnesses, the chemical is known to interfere with thyroid functions.
Health experts can’t offer many answers because they don’t know how far the plume has traveled in the underground aquifers or how many people in the area suffer from thyroid disorders. And, because the chemical has only been on the list of contaminants for a few years, there are no enforceable state or federal standards about how much perchlorate can be in drinking water safely.
In a class-action suit filed late Friday, five homeowners are asking that Olin, the company responsible for the contamination, create a program to survey and monitor the health of current residents and others who lived in the area after 1955. It also asks that Olin pay all costs for medical diagnosis and treatment for residents.
Olin made highway safety flares in south Morgan Hill from 1955 to 1996 and has said it will pay all the costs to clean up the site. During the past four decades, the perchlorate plume has spread at least seven miles south of the flare manufacturing site.
Perchlorate Is Used For Solid Rocket Fuel
Perchlorate is a salt used as an oxidizer for solid rocket fuel, highway safety flares, matches and fireworks. It dissolves readily in water, moving with the steady flow in the subterranean aquifer that lies under the South County from Cochrane Road south.
When ingested, the chemical disrupts the thyroid gland’s intake of iodine from the bloodstream. While this won’t affect most healthy adults, experts say that people with existing thyroid disorders, or pregnant women and very young children, are at risk.
“For healthy adults, the consequences really aren’t very severe at concentrations that would be of concern to people who have thyroid problems or pregnant women and newborns,” said Kevin Mayer, the national perchlorate coordinator for the U.S. Environmental Protection Agency.
In general, perchlorate affects adults only if there is insufficient iodine in the person’s diet — salt, meat, seafood, butter, cheese and even seaweed kelp contain sufficient amounts or there is so much perchlorate present that it “overwhelms the iodine,” said Santa Clara County Health Officer Martin Fenstersheib.
Basically, perchlorate competes with iodine for a place in the gland, he explained. “The thyroid may not make enough hormones while the perchlorate is there,” Fenstersheib said.
One thing that is known about perchlorate is that it leaves the body quickly. “It’s not a poison,” Fenstersheib said, and “doesn’t hang around in your body.”
Both the federal Environmental Protection Agency and the state are working to set enforceable maximum contaminant levels for perchlorate in drinking water. California will be the first state to set such a standard.
The state Department of Health Services has set 4 parts per billion as the “action level” at which water retailers must notify customers, although they are not required to shut down the well. That’s also at the lowest limit of detection for most laboratories.
A law written by state Sen. Byron Sher, D-San Jose, requires the state to adopt a maximum allowable level in drinking water by Jan. 1, and the California EPA has recommended a range of 2 ppb to 6 ppb.
The federal EPA is proposing 1 ppb (part per billion) as the level the agency considers safe to consume each day, after recent studies about the effects of the chemical in developing organisms.
A decade ago, perchlorate was on hardly anyone’s radar screen. Scientists hadn’t yet decided it was a groundwater contaminant, although its effects on the thyroid were known a half-century ago. Scientists have been able to detect perchlorate levels below 400 ppb only since 1997.
After extensive review of the EPA studies, the agency will set a scientific benchmark of allowable levels in drinking water. Regulation will take several years longer as policy-makers set a national standard based on scientific advice and a number of other factors such as risk and cost.