Perchlorate Standard in Massachusetts

The nation's first drinking water standard for perchlorate has been proposed by the state of Massachusetts at a level of 2 ppb, an order of magnitude lower than the EPA's current "reference dose" (recommended safe limit).  The state claims that the proposal reflects growing scientific evidence of exposure to perchlorate from various pathways other than water. The article did not mention the growing evidence that perchlorate occurs naturally as a result of energetic atmospheric chemistries.

Separately, an EPA advisory committee on children's health has submitted a letter to EPA Administrator Stephen Johnson urging the agency to set a federal water standard for perchlorate and/or to issue a health advisory for drinking water that will specifically protect infants. At issue with the current clean-up goal of 24.5 ppb for Superfund toxic waste sites, the committee cites factors such as infants' extra fluid needs and lighter weights as factors in their opinion. Various toxicological experts have gone on record as saying that long-term exposure to perchlorate at levels as high as 200 ppb are generally expected to be safe, and included sensitive sub-populations such as nursing infants and fetuses.

An article reflecting this news and its attendand political controversy was published in the March 15, 2006 issue of the Wall Street Journal.

WSJ Weighs in on Perchlorate Issue

The December 29, 2005 issue of the Wall Street Journal featured the last of a series of front page articles on the theme of Toxic Traces: New Questions About Old Chemicals, and specifically revisited the issue of what level of perchlorate exposure poses risk to human health. Central to this issue is  "the burgeoning science of low-dose chemical exposure" and the uncertainty that governs what is known about perchlorate effects in the parts per billion realm -- essentially leading to a standoff between elements of the DOD and the EPA. The critical overview reflects the interests and concerns of various parties, including those who feel that public and private dollars would be better spent on more clear-cut health issues that are not burdened by  "what-if" scenarios driven by "precautionary principle" reasoning. Taken to its limit, the precautionary principle would dictate that if the evidence about a product or technology is in any way incomplete, it should be prohibited or at least stringently regulated. Unfortunately, the WSJ article did not represent or sufficiently develop several arguments that mitigate against the severe and costly regulation of perchlorate  (www.wsj.com)

The factors listed below play into the decision by the National Research Council in 2005 to recommend a maximum safe exposure level equivalent to about 24 ppb perchlorate. Toxicologists are on record as supporting a limit of 200 ppb. Elements within the EPA want a one ppb limit.  The state of Massachusetts recently declined to establish, at this time, a perchlorate-specific water quality standard that would have demanded compliance to a one ppb limit, several times more stringent than that adopted by the California EPA. Pertinent factors within the debate include (but are not limited to) the following:

• Perchlorate has been accepted for 50 years for the treatment of thyroid conditions, usually involving exposures 1000 times commonly found environmental levels.
• Occupational studies have found no anomalies in workers exposed to perchlorate at levels well above environmental exposure.
• Extrapolation of rat studies to the human condition is a problematic exercise at best.
• The rat data represent a precursor effect far removed from an actual adverse effect.
• Perchlorate is eliminated from the human body in a very efficient manner.
• The effects of nitrate ion on thyroid function, while less acute than perchlorate effects, can be represented as a greater problem because of the prevalance of nitrate exposure in humans.

Because of various uncertainty factors, it is very difficult to separate the science from the politics of the perchlorate debate. One wonders how that debate would develop if perchlorate were essential to the manufacture of chocolate rather than munitions and propellants.

Massachusetts Perchlorate Study

In August 2005, the Massachusetts Department of Environmental Protection issued a draft report on perchlorate in state water bodies. The agency tested 600 public water supply systems and found only nine of them to have a perchlorate content above the detection limit of one ppb, thus concluding "the perchlorate ion is not pervasive in the surface water or ground water in Massachusetts." The report identified perchlorate as coming from explosives used in blasting, from fireworks, and from sodium hypochlorite solution used in water treatment facilities and as household bleach. There is some evidence of anaerobic degradation of perchlorate, and the study found a reduction of perchlorate content in water flowing through septic systems.  This would seem to mitigate against the development of more specific standards to limit perchlorate content in drinking water or discharge waters (POTWs) in Massachusetts.

Slippery Teflon Charges Won't Stick

By Gregory Conko and Henry I. Miller

The uncanny ability of President Ronald Reagan to deflect public criticism won him the nickname, "The Teflon President." Ironically, now it is Teflon itself that is facing the heat, as anti-chemical groups and trial attorneys have joined forces to cook up controversy over a product that has become one of America's most trusted consumer icons, as well as an integral part of our language, like Thermos and Kleenex.

The radical Environmental Working Group has charged that the billions of meals worldwide prepared every day on Teflon cookware are being contaminated with "Teflon toxins," and two Florida-based law firms have filed a $5 billion class-action suit in eight states against the manufacturer, DuPont, for "failing" to warn consumers about the product's alleged dangers.

But, like many product-safety scares these days, these charges are bogus. And that really fries us.

The truth is that an EPA advisory panel has recommended more testing of a chemical known as PFOA, which is used to make non-stick coatings and numerous other products, including those trademarked as Teflon. However, both Teflon and PFOA have been the subject of numerous studies, and there is not a shred of evidence that either poses a human health risk.

Only when tested at very high doses on mice and rats, has PFOA been shown to cause cancer, but under the EPA's current policy, such questionable animal data are enough to classify the chemical as a "likely human carcinogen." That high-dose test methodology is unreliable, though, because it is totally irrelevant to real world exposures. In fact, a wide spectrum of naturally occurring chemicals -- including many that are common constituents of our diet -- also cause cancer in lab animals at high doses. At the very low doses to which humans are actually exposed, most natural and synthetic chemicals are completely harmless.

Most compelling of all, PFOA is not present in the actual non-stick cookware coating -- including pots and pans coated with Teflon. A recent peer-reviewed published study confirmed that there is no detectable consumer exposure to PFOA through Teflon-coated cookware. Even the chronically over-cautious European Food Safety Administration recently dismissed the trumped up concerns and allowed the continued use of non-stick coatings in cookware. Studies in Denmark and China also have also confirmed Teflon's safety.

Finally, the risk-averse U.S. EPA has stated quite clearly that it "does not believe there is any reason for consumers to stop using any consumer or industrial related products" as a result of their ongoing investigation into PFOA.

That should be the end of the story. But the persuasive evidence against any injury caused by Teflon doesn't faze attorney Alan Kluger. "I don't have to prove that it causes cancer," he said. "I only have to prove that DuPont lied in a massive attempt to continue selling their product."

What's going on here?

The typical formula used in these big class action suits is to trump up some bogus health claim, demand a quick settlement, and then cut and run before the facts are weighed in litigation. The lawyers know they can count on people's fear of chemicals and their natural concern for the health of their families to generate public outrage. Teflon has been around for half a century and is ubiquitous.

As toxicologist and president of the American Council on Science and Health Dr. Elizabeth Whelan has pointed out, "Teflon, probably more than any industrial product, is the poster child of modern technology, one that has made our lives easier and more enjoyable." It is precisely the product's "stellar success story [that] makes it a very ripe target for those who spew chemical-phobia in their crusade to eliminate the tools modern industrial chemistry has given us -- pesticides, pharmaceuticals, food additives, and more."

Another factor in pursuing bogus claims is that the plaintiffs' lawyers know they can often count on a major corporation like DuPont to capitulate in order to protect its reputation. In 2004, for example, the company paid an $82 million out-of-court settlement to the residents of Parkersburg, West Virginia, who alleged that PFOA from a nearby DuPont plant had tainted their water supplies -- in spite of the lack of any supportive evidence. In fact, a University of Pennsylvania study examined neighbors of the Parkersburg claimants who used the same water source and found no harmful effects.

We hope that this time DuPont fights to the bitter end to expose this class action charade.

Lamentably, whether litigation is involved or not, activists commonly misrepresent environmental or public health risks. Undeterred by the facts, many self-styled public health advocacy organizations like the Environmental Working Group, Greenpeace, Center for Science in the Public Interest, and the Union of Concerned Scientists know that to have an impact, their charges need not be true but merely plausible. The media -- whose motto is "if it bleeds, it leads" -- does the rest: "Are you eating cancer-causing chemicals in every meal? Details at 11!"

Also, it's hard for the public to shed a tear for the misfortunes of a corporate goliath like DuPont, the creator of the Teflon miracle and the owner of the trademark. The days of "Better Things for Better Living through Chemistry" -- DuPont's advertising slogan until 1981 -- are long gone, as chemicals are now looked upon with suspicion by many people. Moreover, big multinational companies of any kind are largely unappreciated, no matter how many jobs they create or lives they enrich.

Distortion and manipulation of science by self-styled consumer groups in pursuit of political agendas and by voracious plaintiffs' attorneys looking for the next big score erodes our society's capacity to innovate and prosper. It jeopardizes safe and beneficial products and harms manufacturers and their employees. In the absence of persuasive evidence vetted by experts, consumers should reject the attacks on Teflon, as well as on other essential products like vaccines, pesticides, medical drugs, and many others. The charges just won't stick.

Gregory Conko is a senior fellow at the Competitive Enterprise Institute. Henry I. Miller, a physician and fellow at the Hoover Institution, was an FDA official from 1979-1994. Barron's selected their book, "The Frankenfood Myth," as one of the 25 Best Books of 2004.

California Regulation of Perchlorate

For those interested in the treatment of the perchlorate issue in California, the link below provides detail on the current draft of the guideline being developed as "Best Management Practices for Perchlorate Materials."   

http://165.235.111.242/LawsRegsPolicies/Regs/Perchlorate_regs.cfm

Of the many facets presented in the outline of "regulation concepts," a couple stand out:  1) new draft language for the BMP chapter, and 2)  points of input for letters and comments in response to various aspects of the proposed regulatory guidelines.  For example, see the emphatic reaction to the regulation of the use and disposal of road flares, situations where those charged with ensuring public safety may be put at significant risk for no substantial environmental gain.

EPA Ass't Administrator Named

The confirmation by the U. S. Senate of the appointment of Dr. George M. Gray, former Executive Director of the Harvard Center for Risk Analysis, to the position of Assistant Administrator for the Office of Research and Development at the USEPA has elicited the following response:  "Dr. Gray has spoken extensively on the topic of risk-based, scientific approaches to developing new regulations. He brings to the EPA significant experience  in the field of risk characterization and risk communication, with a focus on food safety and agriculture and chemicals in the environment." 

Dr. Gray has been prominent in efforts to enact cost-benefit legislation for the state of Massachusetts during the past several years.

Minute Dose Health Risk Issues

The July 25, 2005 edition of the Wall Street Journal featured a front page article by Peter Waldman on the issue of the effects of minute doses of chemical agents on hormonal processes that impact human health. The evaluation of effects of substituents in amounts as low as parts per trillion "challenges an axiom of toxicology stated by the Swiss chemist Paracelsus nearly 500 years ago:  The dose makes the poison." 

There are many complicating factors. Some chemical agents seem to require the presence of a secondary agent in order to manifest biological effects. Accurate analytical measurement of part per trillion levels of analytes presents significant challenges. And the possibility or likelihood of natural occurrence of some agents (such as perchlorate) commonly regarded as "industrial chemicals" further complicates the "risk vs. benefit" debate. 

For more information go to  www.wsj.com.

IC/MS Perchlorate Analysis

Analysis of perchlorate at low ppb levels has been complicated by the possible occurrence of both false positives and false negatives due to matrix effects and co-eluting substances detected by non-specific conductivity detection.  The July 2005 issue of American Laboratory News  (Vol. 37, No. 15) features an article (pp. 16-20) that describes how an isocratic IC system and a single quadrupole 1100 MSD can determine perchlorate at sub-part per billion levels.  It should be noted that this detection limit likely intrudes on the levels at which perchlorate may be found as a naturally occurring substituent of groundwater in many areas.  The publication web site is www.americanlaboratory.com.   

Perchlorate Remediation Update

The Volume 49 No. 31 (July 2005) issue of Mainstream, published by the American Water Works Association (AWWA), provides an update on the efforts in perchlorate remediation in the San Bernardino Valley (CA) water systems. Various multimillion dollar projects involving private, public, and government funds are being used to address the presence of perchlorate at levels as low as four parts per billion. Some wells having perchlorate levels at ten ppb or less have been taken off-line. It was noted that California has not set a maximum contaminant level but does have a guideline of six ppb. References to both treatment costs and "costly legal fees" are prominent in the article. Both modified granular activated carbon filtration and ion exchange technology were mentioned. One factor not mentioned was the National Academy of Sciences NRC report of January 2005 which recommended a level of 20 parts per billion perchlorate as safe for consumption in the U.S.

This AWWA report is expected to be available at the following link: 

www.awwa.org/communications/mainstream.

How does EPA determine drinking water exposure guidelines?

Both the scientific community and the public need to develop a thorough understanding of the mechanism used to calculate the guidelines (as Oral Reference Dose, or RfD) used to limit drinking water exposure levels. The EPA can use a variety of uncertainty factors in the derivation of the RfD. These uncertainty factors are based subjectively on study methods, toxicological data bases, and other information, and typically are given values of 1, 3 or 10. Whether these factors are fairly applied on a systematic basis can be a subject of considerable debate.

One important issue is determining, for a given exposure situation, what is the critical endpoint in the critical study. It is in the EPA's authority to choose that critical data point. In addition, if there is a dose at which no adverse effects are observed, this becomes the NOAEL (no-observed-adverse-effect-level) upon which the reference dose (RfD) is based. Otherwise, the RfD is based upon the LOAEL (lowest-observed-adverse-effect-level).

The following relationships can be used to derive the RfD, which in turn is translated into a Drinking Water Equivalent Level (DWEL) related to individual body weight.  The DWEL is found by multiplying the RfD times the body weight in kg , divided by the volume of water consumed per day.  This in turn is equal to the term below, in which the U factors are typically 1, 3 or 10 (greatest uncertainty).

NOAEL or LOAEL (mg/kg-day)                                                                     UFl x UFa x UFh x UFd x UFs                        

where:

UFl  =  the LOAEL uncertainty factor, intended to compensate for the use of a LOAEL rather than a NOAEL as the basis for the RfD

UFa = interspecies uncertainty factor, intended to account for uncertainty involved in extrapolating from animal (e.g. rat) to humans.

UFh = intraspecies uncertainty factor, intended to account for variation in response among the human population for the end-point in question, with the particular intention of protecting sensitive subpopulations.

UFd = database uncertainty factor, essentially the completeness of the overall database especially as relates to the critical study.

UFs = subchronic to chronic uncertainty factor, intended to account for the uncertainty involved inextrapolating from a less-than-chronic NOAEL to a chronic NOAEL when a chronic NOAEL of sufficient quality is not available. [Note - this factor was not used by the EPA in the derivation of an RfD for perchlorate because the mechanism of perchlorate action is such that the effects of subchronic exposure fully account for the effects of chronic exposure.]