An article that's been making the rounds at work alleges that fluoride is linked with anemia in pregnant women. The article, Effective interventional approach to control anaemia in pregnant women, looks at a number of women in India, and evaluates whether lowering fluoride intake had a positive effect.
Anaemia in pregnancy and low birth weight babies, a serious public health problem, troubles India and several other nations. This article reports the results of a approach to address the issue.
....
Results reveal that (1) the urine fluoride levels decreased in 67% and 53% of the pregnant women respectively, who attended ANCs during 1st and 2nd trimester of pregnancy. (2) An increase in Hb upon withdrawal of fluoride followed by nutritional intervention in 73% and 83% respectively has also been recorded. (3) Body mass index (BMI) also enhanced. (4) The percentage of pre-term deliveries was decreased in sample group compared to control. (5) Birth weight of babies enhanced in 80% and 77% in sample group women who attended ANC in 1st and 2nd trimester respectively as opposed to 49% and 47% respectively in the control group. (6) The number of low birth weight babies was reduced to 20% and 23% respectively in sample as opposed to 51% and 53% in control groups.
So we have fluoride levels in urine dropping, and at the same time, hemoglobin levels and body mass index increase. In addition, we see a decrease in birth complications.
Looks pretty telling, until you read this from the abstract:
The sample group was introduced to two interventions, viz.: (1) removal of fluoride from ingestion through drinking water, food and other sources, (2) counselling based intake of essential nutrients, viz. calcium, iron, folic acid, vitamins C, E and other antioxidants through dairy products, vegetables and fruits. No intervention was introduced for the control group.
The researchers changed two things at once – reduce fluoride intake, and increase the intake of essential nutrients. After both changes are made, the change in fluoride intake is given all the credit.
It would have been very interesting to see what the effect would have been had the women only gotten nutritional counseling. I suspect there'd have been positive results just from the improvement in nutrition.
From the Washington Post:
The nation's premier public health agency knowingly used flawed data to claim that high lead levels in the District's drinking water did not pose a health risk to the public, a congressional investigation has found. And, investigators determined, the agency has not publicized more thorough internal research showing that the problem harmed children across the city and continues to endanger thousands of D.C. residents.
The agency acknowledged, however, that its 2004 claim that no children had been found with lead poisoning was "misleading," because it referred to only one part of its study. Another part showed that children living in homes serviced by a lead pipes were more than twice as likely as other D.C. children to have unsafe lead in their blood.
Also:
The CDC, which is the nation's principal public health agency, made the confession in a "Notice to Readers" published in an official weekly bulletin Friday. It came a day after a scathing House subcommittee report said the agency knowingly used flawed and incomplete data when it assured D.C. residents in 2004 that their health hadn't been hurt by spikes in lead in the drinking water.
The events represented a full vindication for Edwards. He had embarked on the painstaking, solo investigation primarily because he was outraged that the CDC's original report was being used across the country as a reason to relax concern about lead in the water. Now he has the House report to back up his research.
"Disinfectant by-products that have a nitrogen atom incorporated into the structure are far more toxic and genotoxic, and some even carcinogenic, than those DBPs that don't have nitrogen. And there are no nitrogen-containing DBPs that are currently regulated."
In addition to drinking water DBPs, Plewa said that swimming pools and hot tubs are DBP reactors. "You've got all of this organic material called 'people' -- and people sweat and use sunscreen and wear cosmetics that come off in the water. People may urinate in a public pool. Hair falls into the water and then this water is chlorinated. But the water is recycled again and again so the levels of DBPs can be ten-fold higher than what you have in drinking water."Plewa said that studies were showing higher levels of bladder cancer and asthma in people who do a lot of swimming - professional swimmers as well as athletic swimmers. These individuals have greater and longer exposure to toxic chemicals which are absorbed through the skin and inhaled.
All Mark Miller wanted to do was wash some cars and water the grass in front of his new car dealership.
As the proprietor of Utah's first LEED-certified, environmentally friendly car dealership, Miller wanted to minimize his reliance on water from Salt Lake City's public utility. So his extensive remodel of the building included two large new cisterns designed to capture rainwater for irrigation and car washing. But Miller was surprised to learn that trapping water on his own roof would be illegal.
"The state said no," he explains. "In order to use the system, we had to have an existing water share. It's ludicrous."
Miller is not the only water-conscious Westerner to run afoul of the region's prior-appropriation doctrine. Conservation advocates, including many utilities, have embraced the idea of using water collected from roofs, and stored in cisterns or rain barrels, to reduce reliance on dwindling surface water or groundwater supplies. Yet in Utah, Colorado and Washington, it's illegal to do so unless you go through the difficult -- and often impossible -- process of gaining a state water right. That's because virtually all flowing water in most Western states is already dedicated to someone's use, and state water officials figure that trapping rainwater amounts to impeding that legal right.
Why didn't the LA DWP think of that? All they did was steal the water rights from the Owens Valley.
The slimy ooze inside prickly pear cactuses that helps the plants store water in the desert can also be used for scouring arsenic, bacteria and cloudiness out of rural drinking water, according to research at the University of South Florida in Tampa.Biochemical engineer Norma Alcantar first learned of the cactus's unique abilities from her grandmother, a native of north central Mexico. There, the residual water from boiling the flat, oval-shaped lobes of prickly pear for salads and other dishes was used to clear up cloudy water drawn from the river before use for cooking or drinking.
....
Then, she turned her attention to other water contaminants. The group's more recent research has shown that the mucilage can also form a complex with arsenic, a carcinogenic water contaminant that can occur naturally or from industrial or agricultural pollution.
The arsenic-mucilage complex is large enough that it can be removed by drawing the water through a sand filter.
"Sometimes we get 80 percent removal, and sometimes we get lower than 50 percent removal," Alcantar said. "We don't yet know exactly what it is; we haven't found what are the exact best conditions for the mucilage [to get the most arsenic removal]."
....
Alcantar estimates that one lobe of prickly pear would supply a family of five for about five weeks. Alcantar's team is still optimizing and developing the best system, but she envisions that each family would pass their water through a filter that would periodically be recharged with fresh mucilage from prickly pear grown at home or in the community.
It turns out there's a problem with one system used to remove radon from water.
Because the filters have been removing low-level radioactive radium from the city's water for more than 16 years, they have become slightly radioactive.
"When we went to remove them, we learned they were considered low-level radioactive waste and it would have cost $100,000 for disposal," he said.
Radon has a half-life of 3.823 days. That means that after a month, only 0.4% of the original radon would be left. Each succeeding month would reduce whatever radon is in the system by another factor of 230. So why have these filters managed to accumulate radioactivity for 16 years?
Radon is part of a decay series. Uranium decays to thorium, which decays to protactinium, and so on. Radon is seven steps down from uranium, and after radon decays to polonium, there are another eight steps before the series ends with lead-206, a stable isotope.
One of the steps is lead-210, which has a half-life of 21 years. While it's decaying away slowly, more radioactivity is being added as more radon is captured and starts the decay process in the filter. To be sure, eventually the levels would reach a break-even point, but that would be after several decades. (After 63 years, you're up to 95% of the final level; after 84 years, you're up to 98%.)
Lead-210 is a mixed beta and gamma emitter, so you need to spend at least a little effort shielding the radiation. And the level of the radiation is not the level that's found in the water, but rather the level found in however many millions of gallons pass through the filter over a decade. If you have a picocurie of radon per liter of water, and you process one million gallons per day, you wind up with some 15 or 20 millicuries of lead-210 trapped in that filter. That's quite a lot of radioactive material.
Apparently, it's going to cost $100,000 to dispose of the filters in a low-level waste dump.
Update: The article said "radium" and I was thinking "radon", because it's a consideration in local water sources. The half-life of radium is 1620 years, so it will pile up in filters for quite a while -- up to whatever quantity the filter will hold.
Orange County is now gearing up to do what Los Angeles tried to do some years ago. It makes sense -- the city of Los Angeles pulls in some 600 million gallons of water each day, and dumps 400 million gallons into the sewers and storm drains over the same period. If we could capture and recycle all that water, we could cut our demand on aquifers and snow melt by two thirds.
Some communities have used reclaimed water for decades to recharge their drinking water supplies. In Virginia, recycled water is added to a stream feeding the Occoquan Reservoir. In Los Angeles, treated wastewater is added to the Montebello Forebay, where it percolates through the soil to replenish the groundwater supply. Also in California, the Orange County Water District's (OCWD's) Water Factory 21 facility reclaims wastewater that is then injected into aquifers to provide a pressurized barrier against seawater intrusion into groundwater.
To meet additional need to prevent such intrusion and to meet increased demand for drinking water, the California Department of Public Health, along with the Santa Ana Regional Water Quality Control Board, approved OCWD's new state-of-the-art water reclamation facility on Jan. 10. The Advanced Water Purification Facility (AWPF) will yield 70 million gal of drinkable water per day, or about 10% of the district's daily need for 2.3 million residents. "It will give us a supply unaffected by drought," notes Mehul Patel, OCWD's principal process engineer.
The final treatment step at AWPF removes low-molecular-weight organics by adding hydrogen peroxide and irradiating with ultraviolet light. Hydroxyl radicals or hydroxide anions will oxidize at least some of the remaining organic contaminants.
WHEN WATER exits the plant, it goes to one of two places. About half is pumped to the coast, where it is injected through wells to form a hydraulic barrier to prevent seawater intrusion into groundwater. The other half is destined for a percolation pond, which is essentially a giant lake set in permeable soil that allows water to percolate down to blend with the groundwater table. Additional filtering occurs in the soil, where naturally occurring bacteria may break down any remaining contaminants. Studies done for the original Factory 21 reclamation plant using noble gases as tracers demonstrated that it takes more than six months for water to travel from injection wells or percolation ponds to drinking water well intakes.
AWPF was more than a decade in the making, incorporating design, process validation, construction, and regulatory approval. The facility's end product is water that meets or exceeds all drinking water standards. "There are hundreds of constituents that we have to test for and then report," OCWD's Patel says, "and there are minimum standards for all of them."
The difference between Orange County and Los Angeles? Orange County appears not to have had a mayoral candidate trying to ride the issue into office.
(Hat tip: John Ray)
World Watch Institute points out that bottled water is not only more expensive than tap water, but also impacts the environment more.
"Bottled water may be an industry winner, but it’s an environmental loser," says Ling Li, a fellow with the Institute’s China Program who authored the update. "The beverage industry benefits the most from our bottled water obsession. But this does nothing for the staggering number of the world’s poor who see safe drinking water as at best a luxury, and at worst, an unattainable goal." An estimated 35–50 percent of urban dwellers in Africa and Asia lack adequate access to safe potable water, according to Worldwatch’s State of the World 2007 report.....
In industrial countries with highly regulated water supplies, tap water has been proven to be just as safe, or safer, than its commercial counterpart. In the United States, regulations concerning bottled water are generally the same as for tap water, but are weaker for some microbial contaminants. The U.S. Food and Drug Administration, which regulates bottled water at the federal level, permits the product to contain certain levels of fecal matter, whereas the Environmental Protection Agency does not allow any human waste in city tap water. Bottled water violations are not always reported to the public, and in most cases the products may be recalled up to 15 months after the problematic water was produced, distributed, and sold.
I see by the papers, one of the wells supplying water to Los Angeles has been shut down, on account of high levels of hexavalent chromium, or chromium VI. Other wells in the area are threatened, and will be shut down if the plume reaches them.
Los Angeles water officials have turned off a drinking water well near Burbank Airport, the first of what may be many wells to be idled as a costly result of a new spreading plume of underground chromium pollution.
You might also be interested in this, for reference, from the "hot topics" factsheet on chromium.
In the San Fernando Valley, 14 of 84 DWP wells contain detectable amounts of chromium. However, individual wells do not represent what customers actually receive since many well supplies are combined for use. The water served to LADWP customers is consistently below the detectable level of 5 parts per billion for total chromium. Nonetheless, LADWP is proactively researching treatment alternatives for chromium removal, and will be prepared to meet any new standard the State establishes.
About Filtration Systems
The Los Angeles Department of Water and Power is not recommending that its customers use filtration devices as related to the levels of chromium found in drinking water. The levels of chromium 6 in the water served to our customers is below 5 parts per billion (ppb), far below the existing drinking water standard in California which is 50 ppb for total chromium and the Federal standard which is 100 ppb for total chromium.
It is true that we have a few wells with total chromium values over 5 ppb, but their water is treated or blended, or the well removed from service to ensure that the chromium 6 in the water actually served to our customers, is always under 5 ppb.
Ultimately it is the customer's choice. There are a few products that can possibly further remove chromium 6 from your water. For the protection of our customers, we advise them to look for an NSF certification, specifically for chromium 6 removal, on the equipment, and require documentation from the manufacturer that proves that the equipment is certified for use in California by the State Dept. of Health Services as a water purification system.
There are always a few businesses that will try to capitalize on this issue without sharing the full story or misquoting facts to alarm or otherwise mislead the public. LADWP Customers are advised to get all the facts. For more information, visit the following official websites at:
California Department of Health Services http://www.dhs.cahwnet.gov/org/ps/ddwem/chemicals/chemindex.htm
Cal/EPA, Office of Environmental Health Hazard Assessment http://www.oehha.ca.gov/water/phg/
Los Angeles Department of Water & Power http://www.ladwp.com/ Last Updated: April 6, 2001
And I will mention that if you're really worried about chromium VI in your water, you can always add a little vitamin C. This vitamin is an antioxidant, and will change the chemical state of the chromium to chromium III, which is a nutrient.
In an effort to reduce salty waste in the Santa Clara River, the Santa Clarita Valley Sanitation District will give residents 100 percent of the value of their water softeners and will provide licensed plumbers to remove and dispose of the systems. .... Installing salt- or potassium-based water softeners has been illegal locally since March 2003, when it was determined they produced a salty waste that, when discharged into the Santa Clara River, damaged crops downstream.
This story showed up in today's Brown & Caldwell California Water Newsletter. On inspection, it's from the November/December 2002 issue.
It paints a dismal picture of the effects of turning water over to a private firm.
Atlanta's water service had never been without its critics; there had always been complaints about slow repairs and erroneous water bills. But the problems intensified three years ago, says Certain, after one of the world's largest private water companies took over the municipal system and promised to turn it into an "international showcase" for public-private partnerships. Instead of ushering in a new era of trouble-free drinking water, Atlanta's experiment with privatization has brought a host of new problems. This year there have been five boil-water alerts, indicating unsafe contaminants might be present. Fire hydrants have been useless for months. Leaking water mains have gone unrepaired for weeks. Despite all of this, the city's contractor -- United Water, a subsidiary of French-based multinational Suez -- has lobbied the City Council to add millions more to its $21-million-a-year contract.
The Reason Public Policy Institute reports:
On Friday the dissolution of one of the largest and most watched privatization's in the United States was announced. The city of Atlanta and United Water announced that the city would take back operation of its water utility, ending the privatization after four years.
This is from a piece written on January 27, 2003.
And those problems? Well, I'm not sure they arrived with privatization.
Before privatization the city had allowed the water system to deteriorate to near collapse, was being fined by the EPA for violating clean water standards, and had nearly 50% more employees working in the water department than needed. The water department said it needed to double water rates to solve these problems.
Privatization saved the city roughly $10 million per year, brought the system into compliance with EPA standards, and raised rates only 10 percent to accomplish it.
It's interesting to compare the RPPI analysis of lessons learned with the Mother Jones article.
MENLO PARK, Calif. -- Denise Johnson-Kula washes her fruit in bottled spring water. She no longer turns on her faucets or showers in her Menlo Park apartment because she said her water makes her sick.
"Within minutes of being in the shower and breathing the steam, my sinuses were running and I had choking symptoms," said Johnson-Kula. "I also had red, horribly burning skin. The wheezing got so bad I could hardly breathe. I actually thought I was going to die."
Dr. Robert Bocian determined she suffered from chloramine mediated respiratory toxicity.
And what's more, there's an activist group!
One thing that's interesting is that on one side of the question, we have people who insist on removing THMs from their water in order to get the cancer risk down to zero. On the other side, the activist group says:
•THMs are possible but not proven cancer causing byproducts.
So the studies that show problems with THMs in water are questionable, but the studies showing problems with chloramine are gold. Okey-dokey.
By the way, the group cites, without linking, the SFPUC FAQ on chloramine. Here's a link to the top page.
Brown and Caldwell Water News has an exclusive article on the effect two cases before the US Supreme Court might have on the Clean Water Act (CWA).
At issue is, largely, the definition of "navigable waters".
The 1972 act states that the government has the right to protect "navigable waters," but justices must wrestle with how to define that term and whether the law includes smaller creeks that reach remote, navigable waterways. The U.S. government contends that the act extends to wetlands, small rivers and even dry creek beds.
In order to be protected, does a waterway have to be deep enough to float a boat, or is it "navigable" when you can walk through it?
Environmentalists want CWA protections extended to smaller streams, creeks, dry river beds and seasonal rivers, mud puddles, and the like because of the possibility of flushing contaminants into navigable waterways. When it rains, anything that may have been dumped into a dry creek bed will be washed downstream and impact a navigable waterway.
One thing I note in the definitions portion of the CWA:
(7) The term “navigable waters” means the waters of the United States, including the territorial seas.
I'm not sure what "the waters" means. Maybe it does mean that when someone leaves a hose running, that's a navigable water, according to the Act.
Hexavalent chromium is hitting the news again.
Scientists working for the chromium industry withheld data about the metal's health risks while the industry campaigned to block strict new limits on the cancer-causing chemical, according to a scientific journal report published yesterday.
Documents in the report, published in the peer-reviewed online journal Environmental Health, show that the industry conducted a pivotal study that found a fivefold increase in lung cancer deaths from moderate exposures to chromium but never published the results or gave them to OSHA. Company-sponsored scientists later reworked the data in a way that made the risk disappear.
As described, this sounds bad. However, recall the article stating that half of all published reports are actually wrong – either reporting a significant effect that doesn't exist, or finding no link where there is one. Maybe, with this in mind, it's entirely reasonable to look at data very carefully before releasing it.
As it stands, the effect of the proposed limit of one microgram per cubic meter of air will result in an estimated two to nine excess deaths per thousand workers due to lung cancer. OSHA usually aims at one excess death, but in this case decided the cost of attaining that limit was excessive. Even the one microgram limit is looking pretty expensive – 5 billion dollars industry-wide.
In a somewhat hysterical post, Main St. USA notes that 380,000 US workers are exposed to hexavalent chromium annually. If we assume all 380,000 are exposed to this metal over a 45-year working lifetime (the criterion OSHA uses in its calculation), every excess death per 1000 workers represents 380 excess deaths among this workforce. There are a lot of numbers missing from the Washington Post article, but this number may give us a shot at some perspective.
One microgram is expected to cause between two and nine excess deaths, and a five microgram limit, 10 to 45 excess deaths. Based on this, the current "maximum exposure level" of 52 micrograms per liter should yield between 104 and 468 excess deaths from lung cancer per 1000 workers. Are we seeing a 10-47% death rate from lung cancer in elecroplating workers?
The one microgram standard is expected to cost the industry 5 billion dollars per year. I don't know how many statistical lives this standard is expected to change, but let's use 50 per thousand as a starting point. Fifty per thousand, times 380 thousands, gives us 7600 lives saved. Divided into five billion dollars gives us an annual price tag of $658 thousand per life saved.
Furthermore, this standard is applied over the entire 45-year working life of each worker, so really, that price tag needs to be multiplied by the 45 years the worker is exposed to it. That's $29.6 million per life saved, and even if we simply multiply it over the entire industry – basically assuming every worker has a cancer prevented – that's a little over $1.2 million per worker.
The question that always has to be weighed is, given the cost per life saved, is this really the most effective use of our lifesaving dollars?
Local companies, including Rocketdyne, have been blamed for high levels of perchlorate in the groundwater. Now, it seems it's produced at low levels by natural processes.
With data coming in that supported the idea of naturally occurring perchorate, which is the basis of the award-winning ES&T article, the researchers began to consider the implications. “Perchlorate is an iodide transport inhibitor,” points out Dasgupta. “Does perchlorate at environmentally meaningful exposure levels inhibit iodide transport?” In two additional papers in ES&T, Dasgupta and his colleagues have shown that perchlorate is in Texas cow’s milk and, more dramatically, in human breast milk.
So either the stuff occurs naturally, or Rocketdyne has managed to salt the environment with incredibly large amounts of the stuff.
We're still encouraged to worry about the stuff, though:
With so many new avenues of research, it is not surprising that Dasgupta advocates that more environmental studies of perchlorate are needed. Citing arsenic in groundwater, he warns, “Being natural doesn’t make it good.”
It can, though, establish a level we've adapted to. For all we know, it'll turn out perchlorate is a nutrient. Arsenic may be, despite being toxic at high levels.
And remember, oxygen is toxic, in high doses.
Altoona, PA will start using water fleas to test the water in its reservoirs.
The Altoona City Authority said it will use Daphnia water fleas to check water in the reservoirs. The authority recently agreed to pay $4,450 for a Kingwood Diagnostics Q-Tox startup kit and about $10,200 annually to maintain the system.
The City of Los Angeles has been using these critters, along with fathead minnow larvae, to test the effluent from the sewage treatment plant for toxicity. These critters are the aquatic equivalent of canaries – they're a lot more sensitive to poisons in the environment than anything we expect to be in the offshore waters, so as long as they don't react to the plant effluent, it's OK to dump it into the ocean.
Recently, the DWP has started testing its drinking water supplies using Microtox, which uses luminescent bacteria as microscopic canaries. In these bacteria, the luminescence is tied to their respiration, so the intensity with which they glow is an indication of how well they're functioning. If something doesn't agree with them, their life processes slow down, and the glow diminishes.
Really cool.
And the bugs can be freeze-dried, giving them a shelf life of 18 months.
I recall a story... traces of prescription tranquilizers and antidepressant drugs had been found in the water in the UK. The good news is, no one was terribly anxious about it.
Now, a report on prescription drugs turning up in the local aquifers in Los Angeles.
Behind a tangle of willows, every second of every day for almost half a century, recycled sewage has gushed into an El Monte creek and nourished one of Los Angeles County's most precious resources: the drinking water stored beneath the San Gabriel Valley.
Cleansed so thoroughly that it is considered pure enough to drink, this flow from the Whittier Narrows reclamation plant meets all government standards. Yet county officials now report that they have found some potent — and until recent months undetected — ingredients in the treated waste: prescription drugs.
Hmmm. This is, by the way, the same "toilet to tap" water recycling program Joel Wachs thought he could ride into the Mayor's office a few years ago. Years after he had received briefings on the topic, he found the memo on his desk, and decided to raise a stink over it.
Result: Cancel a multi-million dollar project the month before it's turned on, and he's still not Mayor.
But I digress...
The concentrations are so minuscule — in parts per trillion, or a few drops in an Olympic-sized swimming pool — that scientists suspect there is little or no human danger. They acknowledge, however, that no one knows the effects of ingesting tiny doses of multiple drugs continuously over a lifetime.
In the meantime, the newest technology can detect chemicals in parts per quintillion — equivalent to one tablespoon in the Mississippi River.
"The analytical capability has really, really outstripped our ability to understand what it means," said Michael Wehner of the Orange County Water District, which taps a basin replenished by the Santa Ana River, composed almost entirely of treated sewage.
The main concern with these drugs is their effect on aquatic life.
In yesterday's news was a report by the Environmental Working Group on the nation's water supply. Their conclusion: pretty dismal.
Tap water in 42 states is contaminated with more than 140 unregulated chemicals that lack safety standards, according to the Environmental Working Group's (EWG's) two-and-a-half year investigation of water suppliers' tests of the treated tap water served to communities across the country.
I wonder. Did they test for DHMO?
In any event, a little perspective is in order:
...continued in full post...
EWG's analysis also found almost 100 percent compliance with enforceable health standards on the part of the nation's water utilities, showing a clear commitment to comply with safety standards once they are developed. The problem, however, is EPA's failure to establish enforceable health standards and monitoring requirements for scores of widespread tap water contaminants. Of the 260 contaminants detected in tap water from 42 states, for only 114 has EPA set enforceable health limits (called Maximum Contaminant Levels, or MCLs), and for 5 others the Agency has set non-enforceable goals called secondary standards. (EPA 2005a). The 141 remaining chemicals without health-based limits contaminate water served to 195,257,000 people in 22,614 communities in 42 states.
This sounds gruesome, but its bark is a lot worse than its bite. Piece by piece:
EWG's analysis also found almost 100 percent compliance with enforceable health standards on the part of the nation's water utilities...
Firstly: "Compliance" with enforceable health standards does not mean none of the chemical was present in the water – that the water was "uncontaminated" by that chemical. It means the level was below a level set by law or regulations, such as these. Under EPA standards, the maximum allowable level of arsenic in water is 10 µg/liter, or 10 parts per billion. Water that tests out as being contaminated with nine parts per billion of arsenic is "in compliance with enforceable health standards".
Even if the EPA implemented a standard for the remaining 141 chemicals the EWG found in the water, there's no reason to believe the levels would violate those standards.
Secondly, because a chemical is detected we can't assume it's a health hazard. To be sure, the press release describes some contaminants as "linked" to various health problems. These links usually involve small studies that are looking at things that will show up at the level of one in tens, maybe hundreds, of thousands of people. That's an awfully small signal to find in a noisy system. There may not be any significant health effect. In many cases, there just hasn't been enough research to ascertain how much of a health impact there is. The Junk Science page has links to articles showing that exposure to even large amounts of MTBE (one of the listed contaminants) has a relatively minimal and short-term effect on health.
Finally, in comparing the EWG list of detected chemicals with the EPA list, I find something that may be a bit misleading. One example that leaps to my attention is the third chemical listed – tritium.
Contaminant with no Enforceable Health Standard in Tap Water Population Exposed (of 231,439,195) Number of Water Systems (of 39,751) At any level Above health limits At any level Above health limits Tritium 32,230,006 0 80 0 Pollutant from commercial nuclear reactors and research reactors, and government weapons production plants
Looks bad, doesn't it? Here's where the EWG palms a card.
Although "tritium" has no specific maximum standard for tap water under the EPA, the EPA does limit the levels of beta radiation in tap water. Your tap water is allowed to dose you with more than 4 millirem of beta particles and photons (gamma rays and x-rays) per year. If the only source of beta particles and photons in tap water is tritium, the maximum allowed is the quantity that will give you an annual dose of 4 mrem, or about 4% of the average natural background level.
How many of these chemicals are included under other standards? Maybe a very small fraction. Or maybe a lot of them. I haven't gone over this with a fine-toothed comb. But if I can spot one at a glance, I suspect it's not the only one.
Bottom line: there are things far more worthy of worrying about than the chemicals the EWG finds in the water.
