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There’s a Cancer-Causing Chemical in My Drinking Water, But California Isn’t Regulating It

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Consumer Confidence Report Footnote

123 Trichloropropane has been detected in 29 wells in Fresno…. Some people who use water containing it over many years may have an increased risk of getting cancer, based on studies in laboratory animals.

Screen Shot 2016-03-07 at 21.15.23Wait…what? I have two little kids, and my family drinks the tap water. And it might cause cancer? I decided to fork out $200 to get mine tested. And to start digging into how 1,2,3-TCP got into the water.

Turns out, it’s not just Fresno. According to the State Water Resources Control Board, 1,2,3-TCP has been found in about a hundred public water systems across California, mostly in the Central Valley but also in counties like Santa Cruz, Monterey, Sacramento, and Los Angeles.

But many Californians don’t know whether this stuff is in their water, because neither the state nor the federal EPA regulates 1,2,3-TCP in drinking water. So that means public utilities don’t have to test for it, filter it out, or advise their customers if it’s in the water.

That’s even though the state determined it was a carcinogen back in 1992. And the California Office of Environmental Health Hazard Assessment (OEHHA) set a very low public health goal for 1,2,3-TCP in 2009.

“There is no absolutely no question that is a genotoxic carcinogen,” says Robert Howd, a toxicologist who led the scientific review for OEHHA.

There have been no studies of 1,2,3-TCP’s effect on humans, but animal studies showed multiple tumors at multiple sites in both rats and mice.

“The data are very clear,” Howd says. “Virtually nobody is disputing that. There’s just no controversy about this being a DNA reactive carcinogen.”

Howd’s team set the public health goal at .7 parts per trillion (.0007 parts per billion) The only carcinogen with a lower state public health goal for drinking water is dioxin.

How Did It Get Into the Water?

“This whole story begins in the 1930s, the dawn of the age of chemical agriculture” says San Francisco attorney Todd Robins. He represents about 30 communities around the state who are suing over 1,2,3-TCP contamination, and he’s spent the last decade trying to track how it leached into groundwater.

“Somebody at the Pineapple Research Institute in Honolulu got ahold of this sample of what was essentially hazardous waste from a chemical production process at Shell,” he says, “and he used it in some experiments.”

The experiments, Robins says, were to figure out how to control nematodes, tiny microscopic worms in the soil that attack a plant’s roots.

“Shell saw a huge opportunity to take a hazardous waste stream from their chemical plants … and start putting it in barrels, and selling it to farmers,” says Robins. “Then Dow soon followed suit.”

The companies sold the product to farmers as a fumigant, which is injected into the soil.

Robins has compiled a huge stack of documents that show neither Dow Chemical nor Shell listed 1,2,3-TCP on their product labels, even though it was one of several ingredients. One of Dow’s own scientists admitted that the compound had served no function killing nematodes.

Robins shows me a 1974 memo where Dow describes some of the fumigant components as “garbage.”

“Some of the most startling information is how clearly the companies understood from a scientific perspective the amount of garbage they were putting into these products,” says Robins, “and knowingly having farmers essentially dispose of their hazardous waste for them on farm fields throughout our state.”

In a few cases, Dow and Shell have paid to clean up groundwater with 1,2,3-TCP. But in the more than 3 dozen cases filed against the companies over the contamination, they’ve never admitted any wrongdoing.

Both Dow and Shell declined my request for a taped interview. They sent me emails saying they couldn’t comment on active litigation.

Dow spokesman Randy Fishback wrote that fumigants with 1,2,3-TCP were part of what he called “historical, highly beneficial agricultural products” that “controlled agricultural pests that otherwise would have caused millions of dollars in annual crop losses.” He added those products have been off the market for several decades, and that “TCP is also associated with certain industrial processes in which Dow had no involvement.”

Tiny Communities Can’t Afford Cleanup

Some of the communities suing Dow and Shell have only a few hundred households, like Woodville in rural Tulare County. Ralph Gutierrez runs the water system here.

“I’m the meter reader, I’m the sewer line cleaner, I do the budget,” says Gutierrez, grinning in his cowboy boots and Dodger hat.

He unlocks the gate to show me one of the town’s two drinking water wells, surrounded by orchards and cow pastures. These wells serve a total of 467 households, and 1,2,3-TCP has been detected in the water at 7 parts per trillion, ten times the public health goal.

“Dow and Shell are the ones that put this into the system,” Gutierrez says. “Obviously, they have money to attack their problems, but when you come to communities like this, they’re all farmworkers.”

Gutierrez says there’s no way he can raise water rates high enough to pay for expensive carbon filtration to keep the carcinogen from reaching people’s taps.

“I wouldn’t want my kids drinking it,” he says. “Would Dow Chemical or Shell like their people to be drinking this water? I don’t think so.”

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