A lot of information on a little topic: EPA's Nanotitanium Case Study

Still stuck in the sunscreen limbo? Wondering which to choose - "chemical" filters or "natural" filters like nanotitanium? While we know chemical filters tend to be absorbed into the skin, should we be concerned about absorption of nanotitanium as well? Or perhaps you're wondering when anyone is going to get around to really thinking about how best to evalute risks of nanomaterials? Well here's your chance to read all about it - at least all about the life and times of nanotitanium in one relatively complete report.

EPA has just releasee their Nanomaterials Case Studies: Nanoscale Titanium Dioxide in Water Treatment and in Topical Sunscreen DRAFT. I haven't read the section on water treatment, but this past winter I was involved in the review of the section on sunscreen - sure to be a hot topic even as summer is sadly winding down. While the report won't help you choose which sunscreen to use, it provides a fairly comprehensive review of nanotitanium.

The document, according to EPA is, "...a starting point to to identify what is known and, more importantly, what needs to be known about selected nanomaterial applications."

And, as they tackle the moving target (in the sense that research and publications just keep rolling in) that is nano from production to product, birth to afterlife they invite readers to:

....consider the questions listed throughout the document and offer specific comments on how individual questions, or research needs, might be more precisely or accurately articulated. If additional questions should be included or if information is already available to address some of the questions posed here, readers are encouraged to provide such comments as well. These or other comments on any aspect of the document should be submitted in writing in accordance with instructions, including the specified time period, stated in a Federal Register notice appearing on or about July 31, 2009 referring to Docket ID No. EPA-HQ-ORD 2009-0495.

So have at it. It'll be interesting to follow the further development of this report.

Chemicals we love to hate, Body Toxic book review

A while back I was invited by American Scientist to write my first ever book review. After having just edited a book that was reviewed (mostly favorably), I was nervous. What if I didn't like it? When reading books about toxics, especially books written by non-toxicologists, my sci-dar is on full blast. Most authors seem to have an agenda whether it's chemicals=bad, or the opposite (although those tend to be written by scientists.) Over the years, I've encountered a few written by toxicologists who seem to have forgotten the "oath" of objectivity, or rather, taken the "better living through chemicals" oath. Although those books are great for teaching (so... who checked out the author's affiliation, the funding source or the publisher?), and readers tend to be self-selecting.

Controversy sells. Wishy washy, we don't fully understand doesn't. It's a problem.

So with some trepidation that my first (and possibly only) book review might be negative, I cracked open Body Toxic, written by journalist Nena Baker. What follows is the uncut version of the review recently published in AmSci:

Teaching toxicology to college seniors and juniors was never easier than this past year. Each week students easily and eagerly fulfilled their “current events” assignment with links and clippings of articles revealing widespread contamination of wildlife or humans, with PFOA and PFOS, PBDEs, PBBs, phthalates, BPA, and atrazine. No longer did I have to rely on stories from the “old days” of legacy contaminants like PCBs, DDT and dioxins - not when there all these great so-called “emerging contaminants.”

Although these chemicals have been around for decades they’ve “emerged” into our collective consciousness thanks to much improved chemical detection methodologies and technologies. As chemists extracted and detected smaller concentrations of chemicals from smaller and smaller tissue and urine samples, chemicals like PCBs, and dioxins were detected not only in parts-per-million or parts-per-billion, and but also parts-per-trillion. Many of those emerging chemicals were there, we just didn’t know it. But it wasn’t simply the improved chemistry that helped raised awareness. As analytic methodology improved, many, including toxicologists were stumped by the “so what?” question. So what does it mean when a fish is contaminated with parts-per-trillion concentrations of dioxin?

Now with improvements and some maturation of toxicological testing, toxicologists are now able to evaluate the subtle effects of smaller and often more environmentally relevant concentrations of potentially toxic chemicals.More importantly over the past couple of decades, toxicologists have expanded the definition of “adverse effect” to include impacts on subtle reproductive and developmental processes which may respond to very small concentrations of foreign chemicals.

The outcome of all this new and improved sensitivity? A greater awareness of all the new and improved products that are in all of us, thanks in part to the Center for Disease Control’s (CDC) 2003 National Report on Human Exposure to Environmental Chemicals. And this is where Nena Baker begins The Body Toxic.

Back then, CDC reported concentrations of 250 chemicals including stain repellents, flame retardants and phthalates along with the old standbys, including mercury lead, and DDT in human blood and urine (data from their subsequent analysis will be released this year.)The report piqued Baker’s interest to the extent that she eventually dropped her day job as a journalist to chase down the answers to three basic questions that we all ought to be asking: 1) Should we be worried about the effects of these pollutants on our health? 2) Can everyday items be responsible for the chemicals inside of us? 3) Don’t regulators already make sure we’re safe from daily doses of hazardous chemicals?

We’ll save the first question for last. The answer to the second question, as everyone knows by now, is a resounding yes, of course. We are all contaminated by bits of everyday items from our kitchens, living rooms, bedrooms, offices, even our hospitals.Is this a surprise? Well, yes and no.We know from the history of fat-loving chemicals like the organochlorines (many now banned nationally and internationally) that we can indeed be “incidentally” exposed to environmental contaminants. No one ever purposefully ingested PCBs (at least not that I know of,) yet we’ve all got them in us. And, more importantly, no was ever asked if they minded being exposed to PCBs, DDT, dioxin or any other of these chemicals. It simply wasn’t and unfortunately still isn’t, a choice.But hey, that was back in the day, before Silent Spring and before the birth of the Environmental Protection Agency, when those chemicals were freely released as pesticides or into the environment both legally and illegally.

To address Baker’s third question, no one can deny that over the past 30 years chemical releases into the environment, food, and water have been greatly reduced thanks to expanded federal regulation. But, as Baker reveals in both the Introduction and in her first chapter, A Chemical Stew, what we are dealing with now is more insidious.These chemicals have flown “under the radar” and into our bodies.Some like bisphenol A were never expected to be released from their chemical matrix or become “available”, others including PFOA and PFOS were thought to break down more rapidly than they did, and still others like certain phthalates managed to be absorbed, apparently unexpectedly, into the body. These are chemicals that many of us never thought would end up circulating our bodies, or worse, those of our children. The second chapter, Chemicals We’ve Loved, explores how we got here from there beginning with the post World War II chemical frenzy, and ending with the myriad of chemicals currently registered by the EPA. In the best of all worlds the book would end here. If they’re registered, then surely EPA must have adequate information to protect the public from exposure to toxic concentrations?

Au contraire. As Baker writes, “under our regulatory structure, ignorance is rewarded: manufacturers have no obligation to test for the safety of substances they sell. [p51]. And we, the public, are ill-informed as to whatever chemicals we may ingest, absorb or inhale. The regulatory structure to which Baker refers is EPA’s Toxic Substances Control Act of 1976. When first enacted, TSCA was a big deal. Writes Mark Schapiro in his book Exposed: the toxic chemistry of Everyday Products and What’s at Stake for American Power, “TSCA was the first effort by any government to assert some level of oversight over the vast amount of chemicals that had been introduced into the marketplace since the end of World War II. With TSCA, the EPA was a world leader in chemical regulation.” [p 132.]

It was a hopeful time. It was a hopeful time. According to an October 1976 EPA press release, EPA’s Administrator Russell E. Train, declared TSCA to be "one of the most important pieces of 'preventive medicine' legislation…..its basic aim is to give public health far more of the weight that it deserves in the decisions by which chemicals are commercially made and marketed, by which they enter and spread throughout the human environment."

Sadly, 30 years later as Baker writes, TSCA is “notoriously weak and ineffectual” [p.7]. A conclusion shared by many others including the General Accountability Office, which concluded according to Baker, that “the EPA has given up trying to regulate chemicals and instead relies upon the chemical industry to act voluntarily when problems arise.” [p.16]

One notorious example of the naivety of such a voluntary program was when DuPont apparently forgot to report that not only was PFOA persistent, but also possibly toxic to humans and wildlife. Subsequently in 2005, DuPont paid over $10 million in fines and EPA initiated a voluntary phase-out of the chemical by 2015 (a program in which DuPont along with several other manufacturers, is a participant.)

And, although not discussed by Baker (perhaps because there isn’t enough to discuss just yet,) is the fate of nanomaterials under TSCA. Nanomaterials encompass a broad category of chemicals with one thing in common they’re small. Really small. One of the advantages of certain nanomaterials is that they act differently than their larger chemical counterparts. But this very quality concerns some toxicologists who fear that nanoized chemicals may be different enough that they may behave differently in traditional toxicology tests. Yet under TSCA, nano-formulations of existing chemicals will not require new registration (or registration as a new chemical). Further, EPA is asking for voluntary submission of health and toxicity data, by manufacturers and users of nanomatierals. At this point, feel free to ask, “when will we learn?”

What went wrong with TSCA and other federal regulations and the consequences of regulatory “misses,” make up the bulk of The Body Toxic’s chapters beginning with the pesticide Atrazine, followed by chapters on phthalates, polybrominated biphenyls, bisphenol A, PFOA and PFOS. And Baker presents a thorough case study of each through a combination of primary literature, anecdotes, interviews, and popular news articles, all cited in the Notes section. As I am often leery of books on toxics, having perused a few too many alarmist articles and books I was pleasantly surprised to find that, beyond Baker’s Introduction where at times words like “ghastly” and images of bathroom shelves “brimming with chemical-laden personal care products” (of course they’re chemical laden – what isn’t?!), the bulk of her writing kept to the science and the policy.

Returning to Baker’s first question, what does it mean to be exposed to all these toxicants at low concentrations, she doesn’t take the easy route and proclaim they’re the route of all evil. “While biomonitoring studies provide a much more accurate picture of our chemical body burden,” she writes, “limitations remain. The studies don’t tell researchers the source of an exposure, how long a substance has been in the body or, most important, what effects, if any a substance is having on human health.” [p.23] She continues with quote from Linda Birmbaum, then director of experimental toxicology at EPA, who acknowledged that “We really need more research to understand whether the levels we’re finding could be associated with adverse health effects.” [p.23] Fortunately Birnbaum, now director of the National Institute of Environmental Health Sciences, should be in a good position to do just that.

The final chapter Reaching Ahead is devoted to the European Union’s new approach to toxics, REACH. The approach is essentially a mirror image of TSCA. Where TSCA requires the EPA to demonstrate that a chemical is a risk to human or environmental health, REACH requires that the manufacturers test and ensure that chemicals do not pose a risk. Where the US was once a leader in chemical control, we can only hope it will become at the very least a follower.

Overall, The Body Toxic makes for informative reading that is not too technical- a plus in this case. Although I would have liked to some synthesis, (for example a discussion of all contaminants discussed which share a common target,) by providing some insight into the complexities of regulation and the workings of scientists Baker’s book opens many avenues for discussion. It’s a good book for a “non-majors” introduction to toxicology.

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[1] [EPA press release - October 21, 1976] http://www.epa.gov/history/topics/tsca/03.htm

Musings of an obsolete toxicologist: nanotoxicology is a whole new world

This morning while walking across town to the Lady Killigrew , a small hipster café located just around the corner from home, I was thinking about a report I’d just begun to draft. The focus was how to evaluate the toxicity of nanoparticles. I was wondering if I’d been too strong in my dismal assessment of toxicology and had hoped that a good slap of cold air (the thermometer outside our kitchen window read -25C) would weed out the dramatic, and clarify the reality.

I’ve pasted some key points below, and while the topic and eventual report are confidential – there’s nothing confidential about the sentiment – I, and many others have been writing about it for a while:

1) The field of nanotoxicology is in its infancy, yet is ever expanding as newly created nanomaterials require assessment of potential health and environmental impacts. I’ve never before had the experience where I’ve considered research from 2006 as “old,” and where, the majority of literature cited is 2008 and 2009. Yet development of a new field within toxicology provides opportunity, and at the same time demands that toxicologists use both hindsight and foresight as they develop the methodology appropriate for these new materials.

2) Hindsight provides us with a glimpse of toxicology as a field, in large part, focused on application as a science catering to the need for rapid assessment and cost-effective regulation. Standardized toxicity testing methodology was developed and implemented as a result, quickly becoming a rigid set of test procedures, a good deal of which, over the years have become obsolete.

3) In part, because of the difficulties with changing test methodologies associated with a regulatory framework (check out the timeline for reproductive and developmental testing – “in development” for what, at least 10 years?) - standardized toxicity testing, useful for screening out the obvious is insufficient for detecting more subtle adverse effects or revealing the impacts of the complex mixtures of contaminants, drugs and naturally occurring chemicals to which we are all exposed.

4) We have an opportunity to consider the history of toxicology as we move forward. Many have expressed concern that “business as usual” may result in failure to adequately evaluate toxicity of nanomaterials. Oberdorster et al., (2005) representing the International Life Sciences Institute Research Foundation/Risk Science Institute (ILSI/RSI) writes “There is a strong likelihood that biological activity of nanoparticles will depend on physicochemical parameters not routinely considered in toxicity screening studies.” Additionally different physicochemical parameters may also affect behavior of particles in media typically used in preparing for traditional toxicity testing, the ability of researchers to adequately evaluate exposure concentrations, and particle behavior in the body. Problems only occasionally encountered in the past.

5) When it comes to some nanomaterials, such as quantum dots and functionalized particles we’re potentially dealing with multiple organic and inorganic materials that may, or may not, be released over a period of time. How do we assess that?

Well, as I wondered if I was getting a bit too dramatic, after grabbing a cup of decaf and ordering a breadboard with mustard I settled in and checked my emails. Bingo. There in the inbox was a link to Peter Montague’s recent article entitled "Can Chemicals be Regulated?" published in Rachel’s Democracy and Health News. Read it and weep.

Or, read it and be hopeful. I really do think that we’re at the proverbial crossroads. We’ve seen the consequences of becoming too rigid, of constrained linear thinking. But this is a new multitasking interconnected networked “wisdom of the masses” kind of world, not just for me and my Lady K compatriots (the majority of whom – to the dismay of the management - are more attentive to their electronics than to their stomachs) but also for those laboring away in research laboratories around the globe.

Maybe I need another slap of cold air, but if we can embrace this new fluidity in information, knowledge, and thinking, perhaps we can embrace a new way of not only evaluating health and environmental impacts of new chemical products, but a new way of using that information wisely.

Silencing Spring: WWRD

First Pulished September 2008 in the Montague Reporter

In her 1962 publication, Silent Spring, Rachel Carson wrote about a spring in the near future potentially silenced by “indiscriminate use of pesticides,” with names like DDT, lindane, aldrin and mirex. What she didn’t write about back then, are the now infamous perfluorinated chemicals used in nonstick and waterproof surfaces, the polybrominated flame retardants that are infused into textiles and plastics, or the triclosan and triclocarban antibacterials in soaps, toothpastes and a range of consumer goods. Back then, no one knew that these chemicals used primarily in consumer products, would eventually find their way into not only you, but also your neighbor, and your neighbor’s neighbor, and, depending on the chemical possibly their uncle in Alaska and definitely the polar bear that just roamed through your neighbor’s neighbor’s uncle’s town.

Instead, Carson chronicled what in retrospect seems obvious now, but clearly wasn't back then. That spraying long-lasting (and by long - I mean decades) chlorinated chemicals like DDT, which accumulate in the fat and are designed to be toxic, on farms, suburbs, even cities just wasn’t smart. But if her expose seems obvious now, then why almost fifty years later are scientists finding, in addition to the remnants of chlorinated pesticides banned years ago, industrial fluorinated and brominated chemicals in water, sediments, wildlife and in humans? And why is one of the “next generation,” shorter lived, barely-bioaccumulative pesticides, atrazine, turning up in surface and groundwater supplies across the nation?

There is no doubt that the publication of Silent Spring wakened the American public to the very real consequences of “better living through chemistry.”

“I was in 8^th or 9^th grade,” recalls my neighbor Jeff, “and learned about it from the mainstream media. It had a pretty big impact – it started to frame the way you looked at things. I remember kayaking down the Connecticut. It was disgusting. But,” he conceded, “none of us were really sure what to do about these things.”

Barely a year old at the time of publication, and not cognizant of books except maybe as suitable teething material, I don’t recall its publication or the impact it had on my suburban life, although I do recall tanker trucks trundling along our road, spraying for mosquitoes and gypsy moths; the shelf in the garage full of bottles and spray cans that my father used to combat whatever ailed his beloved trees and shrubs; and, befitting my current occupation, I recall mixing up my own toxic potions – from cleaning materials stashed under the sink or in the laundry room, and testing them out on the earwigs and carpenter ants that raced along our swing set. Unlike Jeff, I was clueless.

Thankfully, there were plenty of folks who were neither clueless, nor baffled about what could be done to avert the impending environmental disaster described so elegantly by Ms. Carson. Eight years after Silent Spring, the US Environmental Protection Agency, the primary body responsible for registration, release and management of chemicals was born.

Of the December 2, 1970 launch of the agency Jack Lewis, writing for EPA Journal noted, “…Surely no factor was more pivotal in the birth of EPA than decades of rampant and highly visible pollution. But pollution alone does not an agency make. Ideas are needed--better yet a whole world view--and many environmental ideas first crystallized in 1962. That year saw the publication of Rachel Carson's Silent Spring….In fact, EPA today may be said without exaggeration to be the extended shadow of Rachel Carson. The influence of her book has brought together over 14,000 scientists, lawyers, managers, and other employees across the country to fight the good fight for "environmental protection."”

That’s an impressive legacy. But sometimes, I wonder what Ms. Carson would think of her legacy today?

Reading Silent Spring for the first time (I am ashamed to admit), it’s unsettling that nearly fifty years later, albeit on a different scale, Carson’s writing is still relevant. I don’t mean the the details – I think for anyone who didn’t live through those times – or who doesn’t live near farms where aerial spaying is still used – the events Carson described are hard to imagine. It’s been over thirty years since DDT fell from the sky like snow, and “housewives” swept pellets from their front steps or washed the stuff out of their kids’ hair, and the death of so many songbirds suggested a bleak future.

No doubt, we are all better off thanks to the EPA’s slew of chemical regulations and policies, but on a different scale, pesticides and industrial chemicals continue to contaminate water, consumer products, wildlife and us. And scientists, rather than focusing on lethality and reproductive success are now measuring more subtle changes in wildlife like altered reproductive function and development. The perfluorinated and polybrominated chemicals provide examples of history repeating itself – even with regulations in place. Sometimes chemicals slip by because scientists haven’t figured out how to measure them in the environment. Sometimes they slip by because no one expected them to be there, and sometimes they slip by because the industry that produced and released them didn’t provide all the relevant data. But thanks to greater collective environmental awareness ( by consumers, activists, scientists, policy makers and even industry), unlike DDT, it won’t take over a decade to phase-out fluorinated and brominated chemicals – phase-outs for these chemicals are already in progress.

But then there’s Atrazine. The top selling herbicide in the United States, banned by the European Union in 2003, atrazine is an example of a “new and improved” pesticide gone awry. Applied primarily to corn, with minor uses including lawns and golf courses, the EPA estimates that roughly 73 million of pounds of atrazine are applied to crops each year. Compared with the longevity of the chlorinated pesticides like DDT atrazine lasts for merely a blink in time with a half-life 146 days or so (although in these more enlightened days even that’s considered long-lived.) Unfortunately once Atrazine works its way into ground water it may last for years. The result? In the midwest, Atrazine is one of the most commonly detected contaminants in surface and groundwater, additionally it’s been detected although to a lesser extent in groundwater in the Northeast, including Massachusetts. Though detected concentrations often fall well below EPA’s 3 part-per-billion drinking water standards, there are a growing number of studies suggesting that other species, particularly amphibians may be susceptible to much lower concentrations.

University of California, Berkely researcher Tyrone Hayes reported back in 2003 that exquisitely low concentrations of atrazine, as low as 0.1 ppb, altered the steroid hormone balance in frogs, feminizing male frogs and resulting in hermaphrodism and demasculization of the vocal cords. And just recently, Krista McCoy and others, publishing in Environmental Health Perspectives, reported a link between hectares of farmland and feminization in local frogs. Although the authors didn’t measure specific pesticides, among the suspects is atrazine. All this got me wondering – where’s our EPA? Atrazine was recently up for reregistration, an opportunity for EPA to review data accrued over the years since a pesticide is first registered. For atrazine that was 1958. This was well before scientists were clued in to subtle reproductive and developmental impacts caused by small concentrations of chemicals. Nor was consideration given back then, and only rarely now, to the reality that seldom are individuals or wildlife exposed to single chemicals. We are all exposed to complex mixtures of contaminants released by industry, agriculture and from consumer products like soaps, sunscreens and pharmaceuticals.

Surely, I thought, given the pervasive groundwater contamination and the recent data on frogs, atrazine’s registration if not revoked would at least be restricted. At the very least maybe the allowable environmental concentrations (the “chronic criterion”) would be reduced below those found to impact amphibians? Unable to find the appropriate numbers on EPA’s website, I emailed EPA. “We anticipate this chronic criterion, when finalized later next year, will fall within the range of 10 to 20 ug/l [ppb]” wrote Frank Gostomski of EPA’s Health and Ecological Criteria Division. I asked if Hayes’ studies had been included. Yes, was the answer. But if Hayes’ studies hold up to scientific scrutiny –and there seems to be a growing body of literature that suggests that they do - then EPA’s concentrations are way higher than those found to feminize male frogs.

Though hard to imagine in our own backyard where spring peepers and cluckers keep us awake, is it possible that some day thanks once again to “indiscriminate use of pesticides” spring could still be silenced?

Nanothoughts

A while back I posted a few items about nanotoxicology. Back then, I must confess I didn’t know much beyond those few articles. Now that I’ve had some time to really review the nanotoxicology literature here are a few thoughts about the rapidly developing field.

The potential toxicity of nanomaterials or nanoparticles in either human or ecosystems is of concern to researchers, government, non-governmental organizations (NGOs), industry and consumers around the globe. However, even with all of the past experiences with developing and regulating chemicals – even with the knowledge that before new chemicals (or new formulations of old chemicals) blanket the earth we ought to understand their potential impacts – the health and environmental impacts of specific nanoparticles lags far behind nanoparticle technology.

I’ve also learned that although government agencies, research collaboratives and others are working to remedy this situation, the funding available for research on health and environmental effects of nanoparticles, or nanotoxicology, compared with money spent on R&D, is in the millions verses billions spent on development.

But before we despair that once again, the nanokitties have left the residents of Whoville holding the bag, nanotoxicology does have several advantages over other “ancestral” fields of toxicology including:

• Hindsight revealing flawed strategies of the past which led to inadequate prevention and protection (though this one is quickly slipping away.)

• The more global economy, where regulations in one country for example may impact development of a product in another (the newer EU requirements under REACH for example) in addition to greater potential for international collaboration may stretch resources beyond those that any one government might be able to contribute alone.

• Industries wishing to convince us that in addition to the “bottom line,” they really do care about health and the environment have shown some interest, and in some cases taken leadership in the field of nanotoxicology research – or entering partnerships with environmental NGOs (for example Dupont and Environmental Defense).

• These days, the internet provides a powerful mechanism for rapid distribution of government, NGO and academic reports, providing all stakeholders – even us peons who sit at home, our computers our only source of information - access to emerging data, technology, and publications. It will be interesting to monitor the impact of public oversight of the field as it develops.

Yet despite all of this potential, the “state of the science” on environmental and health effects research today is something of a hodgepodge. But more on that later!

Making Lists: Dr. Cal's thoughts on priortizing chemicals

Guest blogger, Dr. Cal Baier-Anderson, a toxicologist at the University of Maryland, Baltimore; and Environmental Defense, adds her own thoughts about prioritizing chemicals (also check out the list created by J. Lowe from Impact Analysis in the comments section of Fav Five.)

A few years ago at a professional meeting I participated in a panel on the chemical perchlorate, which was receiving a lot of attention as an emerging drinking water contaminant. Perchlorate, an oxidizing agent that is used in rocket fuel, can block the uptake of iodide in the thyroid. One member of the audience suggested that focusing attention on perchlorate was a waste of time and money, that there are other chemicals that are more important. Make a list, I challenged the group; professional organizations and industry should step up to the plate and identify the top 10 chemicals of concern, from an industry perspective. It is certainly not an easy task, as Emily pointed out, many different lists can be made, depending on what features are most important.

With tens of thousands of chemicals in commerce, chemical prioritization is a hot topic. The traditional risk assessment process focusing on one chemical at a time requires a lot of data collection: the identification of the most important hazard endpoints (a prioritization process in and of itself); determination of dose-response for the priority endpoint, the characterization of exposure; and the assessment of risks. Chemical prioritization can be based on hazard, it can be based on likelihood of exposure, or it could be based on risk, incorporating both hazard and exposure. Many environmental groups argue that there is so much uncertainty in the risk assessment process that it is better to focus on hazard, emphasizing carcinogens, mutagens, reproductive toxicants, and endocrine disruptors. This has lead to the creation of lists, such as California’s Proposition 65 list of carcinogens, mutagens and reproductive toxicants (CMR), which requires that products containing a chemical on this label their products with a special notice.

Chemicals that can be classified as persistent, bioaccumulative and toxic (PBT) are also considered to be high priority chemicals. EPA initially devised a list of PBT chemicals, but then developed a computer program that evaluates individual chemicals to score them as to PBT properties. Persistence and bioaccumulation are determined by basic chemical properties, whereas toxicity is based on aquatic toxicity data.

With public attention focused on chemicals in consumer products, many companies are critically evaluating their products’ ingredients to determine if they are made with chemicals of concern. But how can we define chemicals of concern? Based on hazard, or based on risk? Some companies have developed their own restricted substances list that contains chemicals that the companies believe to pose some unacceptable risk to their workers and/or consumers. REI has a list, but a simple Google search of “restricted substance list” will uncover many more.

At the recent SOT meeting in Seattle, there was a session on hazard vs. risk-based approaches. Many state governments and large companies are defaulting to hazard-based approaches as a simpler approach to removing chemicals of concern from consumer products. Several prominent toxicologists opined that focusing on hazard without considering exposure will result in time and money wasted on chemicals posing very little risk. But as my colleague noted during the discussion, there are many folks in the environmental community that are wary of our capacity to predict exposure, citing numerous examples where it was initially predicted that there would be no exposure, and the experts were wrong: PCBs, Bisphenol A, phthalates, PFOA, PBDEs…If we can’t correctly predict exposure, then confidence in the risk assessment plummets, shifting focus to hazard.

A new approach is being promoted by some very smart people: alternatives assessment. Rather than making simple restricted substances lists, focus on what are the alternatives and compare using a suite of criteria. These assessments can be used to drive continual improvement in materials safety – protecting workers, the environment and consumers. Makes sense to me!

EU to the Rescue? Regulating Toxic Chemicals

Throughout my professional life, I have, for the most part buried my head in research. That’s what it’s all about - the science - right? Wrong. Not when it comes to toxic chemicals. Back when I was in graduate school, there were some hints that other things, like regulation and risk assessment were important – but I couldn’t be bothered. Even as Sheila Jasanoff, who boggled me with her intelligence and eloquence, led us graduate students through the morass of legalese in her Toxic Torts class, I just didn’t get it. Why laws were written so unintelligibly I could never understand, except maybe to help employ more lawyers.

So twenty years later – maybe even to the semester that I earned the only “C” in my post-secondary career (well – I also pulled off a C in History of the World a well known “gut,” freshman year of college), I am struggling to understand why our country’s Toxic Substances Control Act, the legislation designed to protect us from harmful effects of toxics does not; and why Europe’s new chemical control policy promises so much more.

Thankfully I’m not the only one trying to figure this out. This summer the General Accountability Office or GAO released a report comparing TSCA with Europe’s new Registration, Evaluation, and Authorization of Chemicals (REACH) legislation. Noting one primary difference between the two, the GAO states:

“TSCA places the burden of proof on EPA to demonstrate that a chemical poses a risk to human health or the environment before EPA can regulate its production or use, while REACH generally places a burden on chemical companies to ensure that chemicals do not pose such risks …….” (emphasis added)

You don’t have to be a toxicologist to know how difficult it is to determine that any one particular chemical poses a risk, you just have to read the papers. He says this, she says that, and meanwhile, polybrominated fire-retardants contaminate the dust in our homes, bisphenol-A leaches from baby bottles, and we’re wondering how the gasoline additive MTBE, which now contaminates groundwater across the country could ever have been allowed. But now the EU is requesting that industry take the lead ensuring (as best they can) that a chemical poses little risk to human health and the environment before setting it loose.

Then there are the tens of thousands of chemicals that were on the market prior to the 1980 enactment of TSCA. Unless there was reason for suspicion, those were grandfathered into chemical complacency. And into our food, clothing, air and water.

Unlike TSCA, REACH does not distinguish between new chemicals or old chemicals, according to a recent article in Environmental Health Perspectives REACH will require safety and exposure data on something like 30,000 chemicals currently sold in Europe. Those chemicals that are “carcinogenic, mutagenic, persistent or bioaccumulative or toxic to reproduction” will receive special attention. I just hope the EU has armies of toxicologists lined up to review this stuff!

Many times I’ve harped on how we seem to make the same mistakes over and over again. But it seems the EU has finally looked back before moving forward. When in class, I try to make it clear that being toxic isn’t enough to raise the reputation of a chemical to celebrity status. Exposure matters. How and how much we are exposed to certain chemicals is key. Sometimes exposure takes us by surprise. Who knew that polybrominated fire-retardents would shake free from their products (although one would think that their similarity to PCBs and dioxins might have raised some concern early on about their tendency to bioaccumulate), or that bisphenol-A would leach into water and food to the extent that it does, or that MBTE would wend its way around soil particles into our water, leaving other fuel components behind to be degraded? To address exposure – the EU proposes to consider all uses of a chemical – and to inform all “downstream uses,” clothing, cosmetic, packaging manufacturers for example, of not only the chemical’s properties but also how it behaves in humans and in the environment.

This kind of information, according to Joel Tickner, from the Lowell Center for Sustainable Development, (as reported by EHP), may drive innovation towards less toxic, safer products. According to EHP, “[Tickner] says there is a clear interest of downstream users of chemicals who want the functionality of the chemical but not their toxicity. Companies in sectors such as health care, footwear, electronics, and cleaning chemicals have already started to demand these products from suppliers.”

Amen. And with some trickle down – U.S. companies wishing to supply E.U. with chemicals will have to comply with REACH – there’s hope that we can clean up our act here at home.

Well, we're better off than in the '70s right?

Toxicology fascinates me, and I love passing that fascination on to students eager to learn about how chemical contaminants impact their environment, and what they can do about it. But it’s a difficult science to teach to undergraduates. It’s hard not to talk about environmental contaminants without the doom and gloom. Particularly this semester, when I’ve decided to run a new course, introducing students to emerging contaminants, by having them investigate and write - for this site and others - about what they’ve discovered.

Because really, there’s nothing “new” or “emerging” about these chemicals, except that we’re now aware of their existence in the environment, and in us. As most of my students now know, many of these contaminants have been around for decades. Some were never regulated; some were regulated, but ended up contaminating land and water across the country anyway; some, have taken environmental scientists and regulators by complete surprise.

“How do you not get depressed?” asked one student, head in hands, slouching into the desktop.

“Well,” I reply, “we’re a lot better off than we were back in the ‘70s.”

Whoa, did I really say that?! The ‘70s? Do I have to harken back to the 1970’s to make us look OK now? A time when many environmental regulations were new, and couldn’t help but improve the condition of air, water and land?

I can relate to my students' sense of loss. It’s like having the rug pulled out from under. We all want to believe that all the regulations and regulatory agencies that serve to protect us from harmful chemicals really are effective. And, for the most part they are, and we are better off for it. But these emerging chemicals are more insidious. For decades many of these chemicals have contaminated food, water, us – in part because they were beyond the reaches of the analytical chemist. No one knew they were there - although some might have been predicted to be a problem, others were thought to degrade, break apart into harmless products.

But now, with improved techniques we know that we are not only stardust, but we’re synthetic chemicals as well.

So I point out that there’s hope. I say that even though PFOA and PFOS, which belong to a class of perfluorinated contaminants, were a big regulatory “whoops,” they now are undergoing the appropriate scrutiny, and within a fairly short timeframe, scientists have begun to measure their decline in the environment.

Shortly after that discussion, I sent the students off to investigate their favorite “emerging contaminant.”

Now I’m depressed.

Of the seven different “emerging contaminants” they chose to investigate, four of them, Pthalates, Atrazine, PBDEs, and Nitro-musks are banned by the European Union. But here in the United States? All four are still legal. (OK, California recently banned pthalates and many states have issued bans on specific PBDEs .)

As Mark Schapiro, editorial director of the Center for Investigative Reporting, reveals in his book Exposed , the differences in chemical regulation between the U.S., once an environmental leader, and the EU the rapidly emerging new leader are vast, and like the universe, rapidly expanding.

“All this makes me want to move to Europe,” commented one student, or maybe California.

A nanometer of regulation: EPA, TSCA and nanomaterials

I just came across a little blurb in this week’s issue of Science, noting that the EPA has finally made some decisions about regulating nanomaterials. A quick read indicates that 1) the EPA has decided that for chemicals already registered under their TSCA Chemical Substance Inventory (TSCA is the law enacted to protect us humans and the environment from nasty chemicals – and the inventory is a listing of all those chemicals from which we’re being protected) – nano-formulations of those chemicals will not require new registration (or registration as a new chemical) and 2) they are asking for voluntary submission of health and toxicity data, by manufacturers and users of nanomatierals. Huh.

So what does this mean? I was confused when I first read it. After reading and writing about nanomaterials, I thought one of the advantages of producing these things were specifically (in some cases) because they act differently than their bigger, larger, brothers and sisters. For example compounds like titanium dioxide and zinc oxide were nanoized in the first place was to take advantage of the differences between the larger forms and the smaller. So, I though, maybe the EPA didn’t really mean that.

Fortunately, EPA has an easily readable paper that explains these things – like how they define a new chemical - in great detail. According to their TSCA Inventory Status of Nanoscale Substances – General Approach (2008) paper, EPA focuses on “molecular identity.” In this case, chemicals that have the same molecular formulas, the same crystal structures, the same spatial arrangement of atoms – are the same chemical. That means, according to the EPA, and to borrow from Dr. Suess, titanium dioxide is titatinium dioxide no matter how small.

Why is it important to distinguish a chemical as “new?”

Normally, when a company manufactures a “new chemical,” unless it’s exempt – the company must submit a Pre-manufacture Notice, which then triggers some basic testing. That little bit about “exempt” can be important. In fact, you’ve likely got some of those “exempt” chemicals floating around in you right now. Remember all the hubbub about PFOA and PFOS? Those chemicals in Gore-Tex and Teflon and other products? Well perfluorinated chemicals involved in the production of PFOA and PFOS were granted exemptions, in this case because they were in commerce before TSCA came along. But look what happened. Now we’ve got those chemicals contaminating wildlife around the world. To be fair, it’s possible that would have happened anyway – who knows. But here’s the catch, the exemption was granted with the understanding that under TSCA, should any manufacturer realize that there might be health and safety issues, such information “ [would] be submitted to the Agency…when companies learn of it.” In the case of these products this didn’t happen, and Dupont ended up settling that account for $10 million dollars.

A steep price to pay; and an example which hopefully demonstrates for manufacturers that honesty really is the least expensive policy.

There are various ways a chemical might be exempt. If it’s used only for research and development, it might be exempt. If it’s produced in low volume, it might be exempt. And, if there’s some indication that it would be released in only small concentrations or that there would only be small exposures, it might be exempt.

Bottom line? There will be nanomaterials that will not be required to undergo testing.

Ah but rest assured, EPA has considered that some of these exempt or untested chemicals may have adverse health or environmental effects. You see, they recently announced their Nanoscale Materials Stewardship Program, where according to the program description, “Participants are invited to voluntarily report available information on the engineered nanoscale materials they manufacture, import, process or use,” should they happen to observe anything funky happening with their materials.

Let’s hope they do.

For a good readable explanation of TSCA and how it may or may not apply to nanomaterials check out the article “TSCA and Engineered Nanoscale Subtances,” by Lynn L. Bergeson and Ira Dassa and published in Sustainable Development Law and Policy.