What should we do about the trace chemicals found in drinking water?
Before I talk about the small bits of chemicals often found in drinking water, I want to direct some attention to the national water contamination story going on now because I think it reveals something.
The water is bad in West Virginia
The nation has its eyes on a nine-county area in West Virginia that’s under a state of emergency. A coal-processing chemical leaked into a river and poisoned the drinking water there. Cleanup is ongoing. As they attempt to flush the chemical out of their drinking water systems, officials are trying to determine what level of the chemical is safe.
Ken Ward Jr. of the West Virgina Gazette reportsthat local and federal officials are saying that "1 part per million" of crude 4-methylcyclohexanemethanol (the coal processing chemical) is safe for people to drink.
But Ward is having a tough time finding out what they based that number on:
When asked for more information about where the number came from, Department of Health and Human Resources Secretary Karen Bowling pointed to the "material safety data sheet," or MSDS, from Eastman, the maker of the chemical that leaked. Bowling, though, downplayed the fact that there is precious little toxicological data and few – if any –public and peer-reviewed studies of what the chemical would do to humans if ingested.
There it is. The research on how these chemicals affect our health can be pretty thin.
Trace amounts of chemicals in drinking water
Around much of the nation, the fact that chemicals get into our drinking water has been known for some time. We’re talking tiny amounts. Scientists use terms like "parts per billion" or "nanograms."
The kinds of chemicals found depends on what gets into the water.
Larry Sanford is the assistant manager of the Ann Arbor Water Treatment plant. On a recent tour of the plant, he read from a list of chemicals researchers found going into the drinking water supply. These were trace amounts of chemicals found after the treatment process.
"Ibuprofen…Carbamazepine – I’ve never said that word before. Seventeen b estradiol … 17 a ethinyl estradiol, and estrone, and estriol, and cholesterol, and coprostanol."
The researchers were looking for trace amounts of pharmaceuticals and personal-care products in the water. Our bodies don’t take up all of the medicine in birth control pills, or antidepressants, or even coffee.
You go to the bathroom, and the extra stuff gets flushed down the drain. Small amounts end up in the drinking water.
The water samples in Ann Arbor showed that 19 different types of drugs were going into the treatment plant. And the treatment process took out eight of them.
Sanford called that "serendipity."
"None of these plants were built with the intention of removing any of this stuff," said Sanford. "You just get the removal based on what’s there already. Now when you decide what it is you want to remove, then you’ll have to build a treatment facility that will take that out. It may take other things out at the same time, it may not.”
So what should we do with this information?
That’s what researchers are trying to figure out right now. What’s worth worrying about, and what’s not?
They found more than a third of these plants had trace amounts of 18 unregulated contaminants. In addition to leftover drugs, they found traces of many industrial chemicals, and traces of pesticides too.
Linda Birnbaum is the Director of the National Institute of Environmental Health Sciences. She’s one of the nation’s leading experts on how exposure to these contaminants might affect our health.
I had her look at the list of chemicals found in drinking water. She told me that several of the chemicals found were of some concern, such as the perfluorinated compounds and some of the pesticides.
But she said, "Again the levels are very low."
So should we not be concerned at all?
"Well, the answer is we’re beginning to find out that continuous low level exposure, may in fact be problematic," said Birnbaum.
She says studies are beginning to show that continuous low-level exposure to some chemicals might harm the endocrine system. The endocrine system regulates how your body grows and how you behave.
That’s why researchers are focusing on how this stuff impacts pregnant mothers, developing babies, and kids.
More science needed
The EPA is still gathering more information. They’ve called for more testing at water treatment plants, and they have a list of chemicals they’re watching for. Federal regulators call these "emerging contaminants."
The Ann Arbor Water Treatment Plant just started a year-long monitoring program.
The treatment plant’s Larry Sanford says we might find that these things really don’t have a big impact on us, but they might have an effect on other things.
"The things that live in the water are much smaller, and there may be an impact on them," said Sanford. "And it may be something that would be worth doing something about."
Researchers are looking at what these low-level contaminants are doing to fish.
We’ll take a look at that in our next report.
What you can do
Michigan Radio's Rebecca Williams gathered much of the tape for this story, and in doing so she spoke with Professor Nancy Love of the University of Michigan. Love teaches in the Department of Civil and Environmental Engineering and focuses her work on how environmental biotechnology and engineered water quality treatment systems can clean up these trace chemicals.
The two discussed reverse osmosis treatment systems, and Love agreed that such a system does a good job of removing many contaminants. She said it's often difficult to know what might be in bottled water, but if the label says "treated by reverse osmosis," it's a sign that the water has been treated well.
There's not much we can do about the drugs we excrete (drugmakers could work to make sure we use more of the available medicine, rather than excrete it), but if we have left over medicine in the house, we should NOT flush it down the toilet.
Here's what the FDA recommends.
If you have susceptible people living in your house (kids, or people struggling with substance abuse), you might want to go through the process of disposing the drugs in the trash, rather than storing them in your home while you wait to take them to a drug take-back program.