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In an article published last week in Current Opinion in Pediatrics, a well-respected professor at Mount Sinai School of Medicine in New York, Philip Landrigan, talks about the environmental chemicals implicated in neurodevelopmental disabilities. He discusses the possibility that environmental toxins may be contributing to autism, alerting the scientific community to the need for more research on the effects of common chemicals on brain biology. In his article, he states that synthetic chemicals that are ubiquitous at hazardous waste sites are commonly found in our air, food, and drinking water. And fewer than 20% of these have been tested for brain developmental toxicity.
As I sat reading the article, drinking my cup of tap water tea, I asked myself: What’s in your water?
According to the Environmental Working Group, a watchdog organization that compiles data from water utility companies and state departments, Baltimore ranks 69 out of 100 cities for quality of water with 1 being the best and 100 the worst. The list of chemicals found in the Baltimore City Department of Public Works water is astounding. In the past five years, two contaminants were found to be above legal limits with eleven others above health guidelines. A total of 22 pollutants were identified in Baltimore City water, 14 more than the national average. 22!
Let’s do a rundown on some of them:
- Lead: Even my 2-year old daughter knows this one is bad. The EPA has a restriction of 15 ppb for drinking water, and levels above that value (at 19.3 ppb) were detected in Baltimore City water in the past 5 years with an average of 5.16 ppb overall. Lead is known to cause brain damage.
- Total haloacetic acids (HAAs), Total trihalomethanes (TTHMs), Chloroform, Bromoform, and Trichloroacetic acid: Disinfectants that cause DNA damage and cell death. Carcinogens aplenty. Both HAAs and TTHMs were found above legal limits during the past 5 years. In fact, Baltimore City water ranks among the top 10 cities with the highest levels of TTHMs (at an average of 44.5 ppb).
- Alpha Particle Activity and Radium-226: Radioactive. Any chemical with a number after it is generally bad. Luckily, the data is from only one test and is at very low levels that we probably don’t need to worry about.
- Di(2-ethylhexyl) phthalate: Phthalates, found in soft plastics, have been in the news for awhile now, so you probably have heard their name. They are beginning to be phased out of products in both the United States and Europe due to their toxicity. Phthalates can cause both reproductive and developmental problems. The level in Baltimore City water is at an average of 0.85 ppb. The danger lies in a build-up of phthalates within the body over time.
In his article, Landrigan stresses that in the examples of known chemicals that are relevant to autism (where women were taking certain medications that lead to a higher incidence of autism in their children, such as thalidomide, misoprostol, and valproic acid), exposure occurs prenatally, very early in the first trimester of pregnancy. Therefore, this may be the most important time to avoid harmful chemicals that can affect fetal brain development. Whether or not other chemicals or known neurotoxins, such as phthalates, organophosphate pesticides, and BPA, cause an increase in autism or other specific brain development disorders is not known, and Landrigan encourages future toxicological studies to answer these questions.
But I know one thing for sure: I’m off to get a water filter.
I don’t think you’ll be able to find a filter that will cost effectively remove the disinfection by-products (THM, bromoform, chloroform etc) you mentioned. As an environmental engineer, I can assure you that you are wasting your money on a brita. You should probably mention that the EPAs MCL values are based on a one in a million (p = 10^-6) chance of developing chronic health disorders. As a City resident – of all the things I have to worry about in Baltimore City, the tap water just doesn’t make the list for me. Also, I tested my water when I moved into my house and the lead value I observed was way below (by 2 orders of magnitude) the MCL.
Blaine — Yes, you are correct about EPA maximum contaminant levels. But I do think that we really do not know a lot about the effects of TTHMs and other toxins at the levels in our water, and I would like to see more toxicological studies. That is very comforting to hear about your house water lead content. I still wish it wasn’t present in my water at all.
I had no idea about water filters! I assumed most of them would be able to remove disinfectants. What kind of filter would you suggest? A recommendation from a hydrologist goes a long way in our household…
Amanda I am sorry to tell you this, but lead (Pb) and everything will always be in your water. Even in the raindrops that fall from the sky and the water from the deepest well. So will some trihalomethanes, and the phthalates, and the radium 226. There is a little bit of each of these in every water source. Period. I am not being philosophical either. The laws of thermodynamics and statistics demand it. I have measured less than one molecule of a pesticide in more than a trillion molecules of water from the snow of a mountain more than a thousand miles from the field or garden. The fact of the mater is that there is a tiny bit of every chemical and element that ever existed in every nook of this planet. There is no filter that will remove everything because it will put something back in. Is the filter made of plastic? It will leach some additives (like UV-stabilizers). Is it made of steel? It will corrode and leach some metal oxides. Is it made of glass, it will leach some sodium. The whole point is not to try (like Sisyphus) to isolate ourselves from the chemical world, but to embrace what we know to be safe, avoid what we know (not ‘think’, not have a ‘hunch’, or a concern) but what we clearly know to be unsafe, and not sweat the rest. Our world is made up of chemicals, even (especially) the organic world. Just because its a ‘chemical’ and because its ‘there’ doesnt mean anything, especially that you have to do anything different
and what was that saying about a little bit of knowledge?…
Exactly, and that’s why we need to know more.
It does not seem unreasonable to encourage a better understanding of the hundreds of chemicals in our water with unknown health effects. Sure, most are probably benign at dilute concentrations, but if there are any that are not, it may be possible to reduce them.
Did I every suggest we stop funding science or stop asking scientists to conduct investigations? No.
But two things.
1.Your comments suggest shock that so many chemicals were identified in our water “22!” and that as a result you concluded “I know one thing for sure: I’m off to get a water filter.” This struck me as a slightly chemophobic response that would not likely yield any better health outcomes and I wanted to share with you what I had learned.
2. Your response that you acknowledge the THM’s were below MCL’s but “I still wish it wasn’t present in my water at all.” struck me as un-achievable, but more importantly, evidence of a slippery slope. Namely, if our best information (with a just-in-case safety factor) is used to set safety levels, and you still just don’t want it in your water at all, then your calls for more research ring hollow to me.
At what point will you be satisfied that we know enough to regulate these chemicals? How much testing is enough? How low is low enough? When and how do we decide to “ban” them?
We need to decide that. Because there are literally trillions of different chemicals in this world, and we humans manipulate hundreds of thousands of them. We could stop everything else we are doing as a species and attempt to study the chemicals we use and we would be busy for a century. In the mean time billions of people would die from ignoring public health and infrastructure (if we could even sustain such an endeavor for 100 years).
My question is why? Why should we do more tox studies on THM’s? What is it about THM’s that is more important than, say, smoking cessation programs, or vaccine development, or clean energy research, or anything else that is publicly funded?
Amanda:
Another problem with water is chloramine–now used in many areas as a disinfectant. Washington D.C., for example, had tremendous spikes in lead after the addition of chloramine. People are reporting skin, respiratory and digestive irritations connected with this chemical. Please see http://www.chloramine.org for more information.
I appreciate the thought provoking responses and Amanda’s original post. While the focus was primarily the different chemicals that we might be able to find in our drinking water because of the wonders of modern analytical chemistry, there are plenty of other sources for those same chemicals in our lives. For example, there was a recent interesting article in Science News about how typical cash register receipts contain huge quantities of bisphenol A (BPA; compared to other sources): http://www.sciencenews.org/view/generic/id/48084/title/Science_%2B_the_Public__Concerned_about_BPA_Check_your_receipts.
While everyone has the right to expect that the water coming out of their tap is safe, I think at some point in time you have to some faith in the people delivering your water (while holding them accountable and taking some common sense precautions). Same might be said of any other possible product you bring into your home. Otherwise, you will drive yourself crazy trying to address every molecule.