Since the release of the movie Erin Brockovich in the year 2000, we have come to know of chrom-6, or hexavalent chromium, as a dangerous chemical believed to have caused many people to develop cancer in Hinkley, California. Now, some environmental groups are taking advantage of that fear to raise their own profiles.
What is Chrom-6 and Does it Cause Cancer?
Chromium-6, or hexavalent chromium, is a heavy metal that occurs naturally in areas that have a lot of granite rock. It is produced when granite degrades, allowing trace amounts of the chemical to get into groundwater. In the Inland Empire, people have been drinking this water for dozens of generations with the same levels of chromium.
Chrom-6 has also been used for industrial processes – famously, the company Pacific Gas & Electric added it to water at a plant in Hinkley, California to prevent their pipes from corroding, then allowed that water to sink back into the town’s drinking water supply. Water tested near the PG&E plant have levels of chrom-6 that are 1,000 times higher than just about anywhere else in the country, including Riverside. We have known for a long time that chrom-6 causes cancer when inhaled, but have been unsure about whether or not it causes cancer when ingested (meaning when people drink water that has chrom-6 in it). The reason for that uncertainty is that when chrom-6 reaches our stomachs, our stomach acid actually turns it into chrom-3 (or trivalent chromium) which is beneficial to us. Our stomachs protect us from getting hurt by it.
A 2008 study with lab animals has shown that if given enough hexavalent chromium, the stomach can become overwhelmed and fail to convert all of the chrom-6 into chrom-3. The animals were given water that was so full of chrom-6 it was yellow, and at that point, they did develop cancer. However, our water certainly is not yellow with chrom-6. The amount of chromium-6 found in our groundwater is 1.69 parts per billion (compared with the 2,000 parts per billion found near the PG&E plant in Hinkley). Most importantly, that level of chromium-6 was found in water before it was treated, not as it arrives to customer’s homes.
Scientists can detect chrom-6 in water at 1 part per billion, which roughly equivalent to one drop of water in an Olympic-sized swimming pool. So the amount found in groundwater near Riverside is barely above the detectable level.
An Environmental Organization’s Misleading Claims
The organization pointed to a proposed Public Health Goal of 0.02 part per billion in California as proof that the level of chrom-6 in our groundwater is unsafe, but what they did not point out is that a Public Health Goal is not an actual regulated standard of safety. Public Health Goals are found using statistics, and often do not even take into account whether or not scientists can identify that amount of any chemical in water – which, in this case, they could not. The Environmental Protection Agency requires water companies to test water at various stages in the drinking water supply– groundwater (whether or not it’s used for drinking), water before it is cleaned, water after it is cleaned, water on its way to people’s homes, water after it leaves people’s homes (called “wastewater”), and wastewater before and after it has been cleaned and returned back into the environment. This organization reported data that was collected from groundwater that is never used as a drinking water supply, and from water before it had been cleaned, and neglected to disclose that with their supporters. Their representation of the facts has been highly misleading.
Why Did It Take So Long to Regulate Chrom-6?
Our ability to detect substances in water has increased so substantially that if there is even one drop of a substance in an Olympic-sized pool of water, scientists can find it. It is now practically impossible to find no trace of any chemical in our water. That is why it is so important to learn how much of a trace chemical humans can tolerate without any ill effects.
The first step in regulating a substance is for scientists to methodically look at how much of it we can safely consume over a lifetime. This type of study takes years, because in order for a finding to be considered legitimate, other scientists must review the original work to ensure that it is correct (a process called “peer reviewing”). All of this work results in something called a Public Health Goal. A Public Health Goal is what scientists would want to see in our water if they didn’t have real-world restrictions holding them back. For example, a Public Health Goal does not account for whether or not the technology exists to remove a chemical. It simply looks at the ideal world, which is an important starting point.
Then, it is time to look at the real world. That’s where scientists establish a Maximum Contaminant Level (or MCL). When coming up with an MCL, scientists do look at all of the real-world problems we face when treating water. Does the technology exist to remove the chemical? Is it even possible to find that small an amount of the chemical in water?
We know for now that the amount of chrom-6 in our groundwater is very small – just over the detectable amount – and 1,000 times less than what residents of Hinkley experienced.
Tour the Water Lab
A Sit-Down with Ken Marshall, the Lab Manager for Eastern Municipal Water District
Ken Marshall is responsible for monitoring the safety of tap water used by people who live between Box Springs State Park and Temecula. When I first meet him in the lab at Eastern Municipal Water District, it became clear that he is passionate about his job and he takes his responsibility to water customers very seriously.
On his desk is a picture of his eight month old granddaughter, whom he calls “Princess Fiona.” She and her parents both live with him and his wife.
“I’ve already given her tap water – little tiny drops from a straw. I drink it every day – unfiltered, at home and at work.”
Ken is in charge of testing drinking water before and after it is treated and before and after it is used. He sends results from EMWD’s 34 wells to the state every year, as required. He was deeply insulted when one environmental organization claimed that the water he sends to customers is unsafe.
A Strange Rule that Misleads Customers
“Most people don’t know that the State requires us to send them test results from water before it is treated – not after. We clean the water up, treat for any small amount of contaminants found and that is what customers get when they turns on their faucets.”
He was particularly upset when one environmental organization told the people of Riverside County that those test results represented the water that they actually drink, “It’s just not true.”
Matters are made more complicated by the State’s rule that each water district must publish the reports about untreated water in their annual Consumer Confidence Report, but may not include lab results from the treated water. “I think it confuses people,” he says, “I’ve been trying to get them to let us also publish the lab results from clean water.”
In layman’s terms, it’s like water districts are only allowed to show us the “before” picture in a makeover, and not the “after.” That also means that the Environmental Working Group was passing off the “before” picture as the finished product.
So What’s the Difference?
Good Housekeeping Magazine writer Rachel Moeller Gorman was horrified to find reports about E-coli in her annual Consumer Confidence Report – it would appear to most people, upon scrutinizing their report, that E-coli does show up, but again, that’s the “before” picture. Michelle Karras, a lab technician who works for Ken, talked to us about their constant testing for E-coli.
“I have never seen a sample come up positive in treated water – it hasn’t happened. That’s when all the alarms would go off. We would have to alert the authorities and issue ‘boil water’ notices to the public. But we expect to find it occasionally in untreated water from our wells, and we do. Treating the water kills E-coli.”
They get 55-59 samples every week from wells and from sampling stations throughout their network of pipes that deliver treated water to people’s homes. They test for coliforms (bacteria), E-coli specifically, and nitrates among other things on a mind-bogglingly long list.
“We mix Colilert [a creamy white power] into the sample and put it in an incubator,” she says. “if it turns yellow, that means there is bacteria in it, so then we put it under the UV light. If it glows, that means it has E-coli. I’ve never seen it glow.”
We are talking to Michelle on the day of her baby shower – she is nine months pregnant with her daughter Leah. I ask her if she has continued to drink tap water throughout her pregnancy.
“Yes,” she says. “When you are pregnant, you are caring for someone who is living inside of you. You have to be careful about everything you put in your mouth – and I drink tap water, I know it’s safe. We do so much testing here.”
A Day Without Coffee
Michelle describes how technology has come a long way in recent years: “Equipment for testing emerging contaminants is so sensitive that when we gather samples, the guys have to completely suit up. They are not allowed to drink coffee; they can’t use lotions, cologne, or tobacco. Even the slightest trace will skew the results.”