Few people know their name, but these chemicals have become EPA priority
from Environmental Health Sciences
An obscure family of chemicals – important to the metalworking industry but virtually unknown to the public – is suddenly the subject of scrutiny from the U.S. Environmental Protection Agency. The chemicals, called short-chain chlorinated paraffins, persist in the environment, accumulate in human breast milk, can kill small aquatic creatures and travel to remote regions of the globe. Since their introduction in the 1930s, they have received little attention from U.S. authorities. But now the EPA, in an unprecedented move, has placed the compounds, known as SCCPs, on a short list of worrisome chemicals that the agency may regulate because of the risks they pose to wildlife and the environment.
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| crabchick/flickr |
| Metal-working companies often use chlorinated paraffins as lubricants and coolants. |
By Ferris Jabr
An obscure family of chemicals – important to the metalworking industry but virtually unknown to the public – is suddenly the subject of scrutiny from the U.S. Environmental Protection Agency.
The chemicals, called short-chain chlorinated paraffins, persist in the environment, accumulate in human breast milk, can kill small aquatic creatures and travel to remote regions of the globe.
Since their introduction in the 1930s, chlorinated paraffins have received little attention from U.S. authorities. But now the EPA, in an unprecedented move, has placed the compounds, known as SCCPs, on a short list of worrisome chemicals that the agency may regulate because of the risks they pose to wildlife and the environment.
“We find SCCPs worldwide,” said Tala Henry, acting deputy director of the EPA’s National Program Chemicals Division. “We’ve found them in animals in the Arctic and we have measured them in human tissues in several places around the globe.”
Despite evidence of widespread exposure, few scientists are actively studying the prevalence, toxicity and ecological impact of SCCPs. In contrast, other chemicals that persist in the environment – such as DDT and dioxins – have received far more attention from researchers.
“There is minimal awareness of these compounds,” said Gregg Tomy, an environmental chemist at the University of Manitoba in Canada. “It’s certainly not a chemical that’s on people’s radar screens.”
Chlorinated paraffins are a complex group of manmade compounds, primarily used as coolants and lubricants in metal forming and cutting. They also are used as plasticizers and flame retardants in rubber, paints, adhesives, sealants and plastics. The family of chemicals is organized into short, medium and long-chain paraffins, based on the length of their carbon backbones.
About 150 million pounds of chlorinated paraffins are used annually in the United States, according to the EPA. Ohio-based Dover Chemical Corp., the sole manufacturer of SCCPs in the United States, did not respond to requests for an interview.
“There is minimal awareness of these compounds. It’s certainly not a chemical that’s on people’s radar screens.”
-Gregg Tomy, University of Manitoba Although Europe has restricted use of SCCPs, their manufacture is growing in China and possibly in India, raising concerns that worldwide exposure levels for people and wildlife might be increasing.
China’s production of the chemicals has increased 30-fold in fewer than 20 years.
“We are pretty worried at the moment,” said Jacob Boer, head of the department of chemistry and biology of the Institute for Environmental Studies at the Vrije Universiteit (VU University) in Amsterdam. “The increase of chlorinated paraffin production in China is exponential.”
In an unprecedented use of the 1976 Toxic Control Substances Act, the EPA in December placed short-chain chlorinated paraffins on a list of four chemicals that may pose unreasonable risks to health and the environment. In its action plan, the EPA announced its intentions to investigate and manage those risks, possibly restricting or banning future use of SCCPs in the United States.
It is the first time that the EPA has investigated the compounds, which are already regulated in Europe and under review in Canada.
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| sweart/flickr |
| Traces of the chemicals are found in the breast milk of Inuit women in Arctic Canada. |
Scientists have found the chemicals in the air, on land, in foods, in wastewater and in river and ocean sediments in North America, Asia, Europe and the Arctic, according to a report by a United Nations review committee for the Stockholm Convention, an international treaty that restricts toxic compounds.
“You find them pretty much wherever you go to look for them,” said Tomy, who found significant concentrations in sediments around the Great Lakes region.
SCCPs are accumulating in the fat tissues of freshwater fish such as trout and carp in North America and Europe, marine mammals including Beluga whales, ringed seals and walruses in the Canadian Arctic, land animals including rabbit, moose and reindeer in Sweden, and birds and seabird eggs in the United Kingdom.
Furthermore, certain SCCPs may biomagnify – meaning their concentration increases as they move through food chains, according to a 2008 field study on Lake Ontario trout.
Researchers have also measured SCCPs in human livers, kidneys, fat tissue and breast milk, according to the EPA action plan. Traces were found in 21 out of 25 samples of breast milk from women in London and Lancaster in a 2006 study in the United Kingdom. They also were measured in breast milk from Inuit women in Arctic Canada in a 1997 study by Tomy and colleagues.
“We are pretty worried at the moment. The increase of chlorinated paraffin production in China is exponential.”
-Jacob Boer, Institute for Environmental Studies, Vrije Universiteit, Amsterdam However, since so few scientists are studying the toxicity of SCCPs and their impact on health and the environment, the consequences of the widespread exposure remain unclear.
SCCPs are highly toxic to small aquatic invertebrates and plants that fish and other animals feed on, so the chemicals may endanger aquatic ecosystems. But toxicity to humans and other mammals has been more difficult to determine.
“Whether these compounds are now challenging organisms, I can’t say for certain,” said Tomy. “But because they are so persistent, we can expect them to continue to accumulate. At some point there is going to be serious cause for concern.”
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| chosetec/flickr |
| Chlorinated paraffins are highly toxic to Daphnia, tiny crustaceans in aquatic ecosystems. |
Laboratory tests show that SCCPs are highly toxic to Daphnia, tiny aquatic crustaceans known as water fleas that are important food sources in lakes, streams and other ecosystems, according to a 2000 European Union risk assessment.
To fish, the compounds are less acutely toxic, but chronic exposure damages them. Rainbow trout fed SCCPs in their food developed severe liver tumors, according to a study by Canadian researchers.
The concentrations that caused the fish tumors “were at levels that have been reported in invertebrates and fish from contaminated sites in the Great Lakes. However, the exposure concentrations were likely much greater in these experiments compared with the environment and require further study,” according to the 1999 study, whose senior author was Derek Muir, one of the world’s leading experts on persistent pollutants in fish and wildlife. Requests to interview Muir were denied by Environment Canada.
Other studies have found that SCCPs can cause slight egg shell thinning in mallard ducks and can damage the livers of otters.
Although there are no human studies on their effects, SCCPs can cause cancer in laboratory rats and mice, specifically damaging the liver, thyroid and kidney. Still, the EPA’s action plan and the UN report note that the mechanisms by which these cancers were induced in rodents are not relevant to human health.
For people who do not work in the metal industry, a primary route of exposure to the chemicals is food, according to the EPA action plan.
Researchers in 2002 measured SCCPs in cow’s milk and butter from Europe. They also have been found in many different foods in Japan, including grains, sugar, sweets and snacks, vegetables, fruit, fish, meats and milk. The concentrations were particularly high in shellfish, meat and fats, such as margarines and oils, according to the 2005 study in Japan.
How the chemicals got in the environment is not well understood. “We can confidently say there has been exposure, but exactly how they got there is a difficult question,” said Henry of the EPA.
Although there are no human studies on the effects of the chemicals, SCCPs can cause cancer in laboratory rats and mice, specifically damaging the liver, thyroid and kidney. Possible routes include accidental spills, runoff from disposal, and effluents of sewage treatment plants, states the EPA action plan. “SCCPs can be released during production, transportation, storage, and industrial use,” Tomy said.
The chemicals also might leach out of commercial plastic and rubber products in which they are used as flame retardants and plasticizers, he said. Once in the environment, SCCPs – which do not dissolve in water – bind to sediments and to tiny aquatic organisms, working their way up food chains.
According to Tomy, the inherent complexity of chlorinated paraffins makes it difficult for scientists to identify and analyze them.
“There are only a few labs in the world, and you can count them on one hand, that are actively working in this area because of the complexity,” Tomy said. “This makes PCBs [polychlorinated biphenyls] and PBDEs [polybrominated diphenyl ethers] seem like a walk in the park in terms of detection and quantification.”
“They are difficult to characterize,” Henry agreed. “There’s a difference in interpretation about what a short-chain chlorinated paraffin is.”
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| Bright Star/flickr |
| Beluga whales are among the species contaminated with chlorinated paraffins. |
The result is that the EPA knows far less about SCCPs than other chemicals such as DDT that persist in the environment and accumulate in people and wildlife. “Compared with other persistent chemicals, there’s the least amount of toxicity and exposure data,” Henry said.
Nevertheless, several authorities already have regulated them. Their use and marketing are restricted in Europe. Both Health Canada and Environment Canada have deemed all chlorinated paraffins “toxic” under the Canadian Environmental Protection Act of 1999. Requests to interview Environment Canada scientists who have studied SCCPs were denied.
According to their new action plan, the EPA will consider using the Toxic Substances Control Act to “ban or restrict the manufacture, import, processing or distribution in commerce, export, and use of SCCPs” based on evidence about their environmental and health effects.
Although the EPA says it wants to move quickly to address the risks posed by SCCPs, the agency does not know when it will reach any regulatory decisions.
Under the federal toxics law, the EPA maintains an inventory of over 80,000 chemicals authorized for use in the United States. If a company wants to produce or use a chemical not found on that inventory, they must receive EPA approval by submitting a premanufacture notice that describes its environmental effects.
According to the EPA, some U.S. companies are using chlorinated paraffins that do not appear on the inventory. Tala said the EPA’s first step is to find out why.
Robert Fensterheim, executive director of the Chlorinated Paraffins Industry Association and President of RegNet Environmental Services, said he is not particularly concerned about the potential outcomes of the EPA’s action plan.
The EPA says it wants to move quickly to address the risks posed by SCCPs, but there is no timeframe for any regulatory decisions.“The effects on industry are not going to be broad scale,” Fensterheim said. “Given the limited amount that is produced and used, our assumption is that most people using the product already have responsible management in place. They won’t need to do anything they’re not already doing.”
Fensterheim disputes the EPA’s estimate that 150 million pounds are used annually in the United States. The demand, he said, is closer to 50 or 60 million pounds per year and decreasing.
“This is not a high volume chemical,” he said. “It’s been declining in its production value for quite some time.” The reason for the disagreement may be due to difficulty in defining exactly what a short-chain chlorinated paraffin is.
Manufacture and use of SCCPs have decreased in Canada, Europe and the United States but production is increasing at a rapid rate in China.
“If that production would have to be limited, it would be a major problem for the China metal industry,” said Boer of Amsterdam’s Vrije Universiteit. The increased production rate could also aggravate the ecological risks of the chemicals, he said.
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| wili_hybrid/flickr. |
| Chlorinated paraffins are transported worldwide, winding up in the Arctic. |
The production of chlorinated paraffins in China soared from 20,000 tons in 1990 to over 600,000 tons in 2007, according to a 2009 presentation by Jiang Gui-bin of the State Key Laboratory of Environmental Chemistry and Ecotoxicology in Beijing, China. If this rate continues, production in China alone could soon surpass the entire historic, worldwide usage of PCBs, which remain a contaminant of global concern even though they were banned 32 years ago. Total worldwide PCB production was 1.3 million tons.
India also may be increasing its production of SCCPs, Boer said.
Although SCCPs are specifically defined as having a carbon backbone between 10 and 13 atoms long, there is still plenty of room for disagreement about which industrial products contain which chlorinated paraffins. The TSCA inventory, for example, does not distinguish between chlorinated paraffins of different carbon chain lengths.
Fensterheim said the companies believe the chemicals they use are already covered by the TSCA inventory, but the EPA disagrees.
Despite the inherent difficulties in studying the complex chemicals, Tomy said researchers need to keep monitoring their environmental levels and the toxicity to people and wildlife.
“I would like to believe in the coming years you are going to see more research,” he said.













A Proactive Approach to Toxic Chemicals: Moving Green Chemistry Beyond Alternatives in the “Safe Chemicals Act of 2010”.
Tuesday, July 27th, 2010Kira J. M. Matus*†, Julie B. Zimmerman‡ and Evan Beach
* Corresponding author e-mail: kira.matus@yale.edu.,
On April 15, Senator Frank Lautenberg (D-NJ) introduced the “Safe Chemicals Act of 2010” in the United States Senate. On the same day, Representatives Henry Waxman (D-CA) and Bobby Rush (D-IL) released a discussion draft of a similar bill in the House. These bills present an important and much needed modernization to the management and regulation of chemical hazards in the United States.
The Toxic Substances Control Act (TSCA), the regulation designed to protect Americans and their environment from chemical hazards, has not had its core provisions significantly amended since its enactment in 1976. However, in recent years, there has been increased pressure on lawmakers to rethink the government’s approach to the hazards that arise during the lifecycle of chemical production and use.
There are several drivers for action on chemicals management legislation including (1) recent concerns on the part of nongovernmental organizations and the public about particular chemical hazards (BPA, phthalates, etc…), (2) strict state level chemical regulations, and (3) the enactment of a comprehensive chemical regulation program by the European Community known as Registration, Evaluation, Authorisation and Restriction of Chemical substances (REACH). Further, in 2009, EPA Administrator Lisa Jackson laid out the Obama Administration’s key priorities for TSCA reform (1). This was accompanied by similar proposals from industry and the NGO communities indicating a desire to update TSCA.
Many of the provisions included in the recently proposed legislation, such as shifting the burden of data provision from the EPA to industry, are widely supported. Other elements, such as what data should be provided, how chemicals will be prioritized, the scope of EPA’s authority to take action, and whether it is feasible to “prove” the safety of a chemical have emerged as topics for vigorous debate.
Among the many elements in the current bills, there is one provision, “Green Chemistry”, that has the potential, in the long term, to drastically change the paradigm of the chemical enterprise. Green chemistry, simply defined, is “the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances” (2). Based on 12 Principles (2), Green Chemistry is a systems-based approach for reduced hazard across the entire life cycle of chemicals, from design, manufacture, and use to end of life. It integrates knowledge from across chemistry, engineering, environmental science, and toxicology to reduce, and ideally, eliminate, adverse impacts on human health and the environment.
Both versions of the bill, picking up on Administrator Jackson’s call for green chemistry to be a core element in TSCA reform, explicitly mention the need to “spur innovation in green chemistry”. They address this with a series of proposals under the title of “Safer Alternatives and Green Chemistry and Engineering”. The programs included in this section are laudable. They would provide incentives for the creation of greener, less hazardous alternatives through research funding, expedited review processes, awards, labeling programs, and the creation of four national green chemistry and engineering research centers.
While these provisions are clear signals to the chemical enterprise representing a strong beginning for enhancing green chemistry innovation, there are additional activities and strategies that can and should be advanced. Green chemistry is about more than developing safer alternatives. It is fundamentally a series of guidelines to designing chemicals to reduce, and ideally eliminate, hazard. Green chemistry is a preventive approach based on innovation that improves technical performance, profits, and social benefit. It takes into account long-term, life-cycle thinking.
Green chemistry is at its most powerful as a tool for the development of the next generation of chemical innovations. For new chemicals and materials, it is much more efficient if they are as safe as possible from the outset, eliminating the need to develop alternatives in the future. If the principles of green chemistry were broadly implemented, both in the scientific research community and in industry, they would be a powerful, market-oriented, economically favorable approach to protecting human health and the environment from any potential adverse impacts before they could be manifested.
As discussion of these bills moves forward, stakeholders involved in the process should think more creatively about how the tools of green chemistry can be incorporated throughout the reformed TSCA regulatory process. This means thinking not just about alternatives to chemicals already in commerce, but also about ways to develop and disseminate the knowledge so that new innovations are progressively safer and greener. There are a variety of approaches that should be explored including:
1. Make use of the power of public reporting, and familiarize firms with including Green Chemistry Principles and accounting in their statements:
a. Grant the EPA the authority to include green chemistry metrics in the data that it can require manufacturers to submit as part of their data sets. This could include information such as E-factor (a measure of the efficiency of production), use or generation of hazardous substances based on those chemicals currently listed, and use of renewable energy or material feedstocks.
b. Have the EPA work with NGOs, academia, and industry to create a template for a green chemistry “scorecard” for chemicals and mixtures. Provide incentives for manufacturers who voluntarily submit green chemistry “scorecards” on their products.
c. Make green chemistry information on chemicals publicly available, to spur public awareness and empower consumers.
2. Take advantage of the large quantity of data that will be submitted to develop new tools to make it easier for firms to incorporate green chemistry in their processes:
a. Environmental and toxicological data on existing chemicals could be used to help develop tools, such as molecular design guidelines, that would allow chemical firms to more easily integrate green chemistry into their product development.
3. Support forward-looking research and innovation:
a. Extend research support beyond existing alternatives identification to include development of new chemical products and processes; also identify key challenges and emerging technologies as priority areas for investment in Green Chemistry and Engineering (GC&E) research
4. Foster collaborations:
a. Create programs that allow the government to incentivize collaboration between industry and academia to develop and implement GC&E based technologies.
b. Establish an interagency green chemistry forum to identify and prioritize key areas of GC&E R&D, and mechanisms for integration into various agency programs.
These are just a few of the ways green chemistry could be integrated into a reformed TSCA in a more holistic manner. Green chemistry does not need to be a separate program, but can be woven in throughout the regulation. Instead of relying on a reactive approach, a reformed TSCA presents the opportunity to simultaneously foster a proactive approach. According to both of the proposed bills, the policy of the United States will be “to protect the health of children, workers, consumers, and the public, and to protect the environment from adverse effects of exposures to chemicals” (3). If it is included more broadly throughout this regulatory framework, green chemistry can play an important role in creating a trajectory of chemical innovation that reduces hazards from the outset, which is the most effective and efficient way to protect Americans and their environment.
References
This article references 3 other publications.
U.S. Environmental Protection Agency. Essential Principles for Reform of Chemicals Management Legislation. http://www.epa.gov/oppt/existingchemicals/pubs/principles.pdf. Accessed May 21
, 2010.
“Safe Chemicals Act of 2010.” United States Senate, 111th Congress, S.3209, Sec. 32, 2010.
Tags: GREEN CHEMISTRY, regulations, US States
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