NRDC Recommends Improvements to Chemical Risk Assessment Methods

Chemical Risk Assessment: 

Readers following efforts to improve chemical management and control in the United States may be interested in a recent National Resources Defense Council (NRDC) White Paper, Strengthening Toxic Chemical Risk Assessments to Protect Human Health.  In the White Paper, NRDC reaches several conclusions in reliance on National Academy of Sciences (NAS) findings that significant improvements in both chemical testing and risk assessment are needed to protect people from toxic chemicals.  NRDC emphasizes the need to address the following:

  • the range of human exposures and vulnerabilities,
  • data gaps and uncertainties, and
  • impacts of exposure to multiple chemicals.

NRDC also argues that risk assessment should not presume that a zero effect exposure level exists, unless there are sufficient data to support this assumption.

Each of NRDC’s points is discussed further below.

Citing the NAS findings, NRDC concludes that differences among human exposures and individual vulnerabilities are important determinants of risk.  NRDC therefore recommends that risk assessment consider vulnerable individuals and those who are more highly exposed.  NAS had noted that a broad variety of factors, including nutrition, health status, and psychosocial stress, can increase and individual’s vulnerability to toxic chemicals, and these factors—and their variability—need to be incorporated into risk assessments so that adequate measures can be employed to protect public health.  NRDC also cites an NAS recommendation that risk assessments incorporate analyses that address the uncertainty and variability inherent in a risk assessment—including uncertainty and variability in the measurement of chemical releases into the environment, environmental fate and transport, exposure assessment, dose-response assessment, and risk characterization.  

To address data gaps and uncertainties, NRDC stresses the need for agencies to develop robust risk assessments by updating default factors and assumptions.  It cites the NAS recommendation that agencies update risk assessment protocols based on the best current science.  NAS had identified significant missing default assumptions.  For example, most chemicals are not tested for their potential interference with the hormone systems that govern growth and development, learning, and behavior; the assumption being that chemicals have no effect on hormones—an implicit default assumption that may or may not be true.  And, NRDC noted, allowing such assumptions does not protect health.

NRDC emphasizes the need to address the impacts of multiple chemical exposures.  It faults risk assessment methodologies that focus on only single chemical exposure, rather than endeavoring to model the actual complexity of the world.  NRDC relies on a NAS finding that stressed the need for cumulative risk assessments that address the combined risks posed by aggregate exposure to multiple agents or stressors.  

And finally, the NRDC challenges the standard assumption that there is a safe level of exposure to most chemicals.   NRDC notes that NAS recommends risk assessments assume that all exposures, even low level, are associated with some level of risk, unless there are sufficient data to the contrary.  NRDC explains that science has found many examples of chemicals that increase the risk of various non-cancer health effects—such as reproductive harm and neurological effects—at low doses, without any scientifically-identifiable threshold.

For more information see the NAS reports:

France to require mandatory reporting of nanoscale materials in 2013


France will implement a compulsory declaration scheme for the quantities and uses of nanoparticle substances or nanomaterials produced in, distributed in, or imported to France January 1, 2013. Information about material identity, quantity, uses, and users will be required from all companies producing, distributing and importing nanomaterials, and public and private research laboratories. The declaration scheme will be implemented by the Ministries of Ecology, Sustainable Development, Transport and Housing; Economic, Financial and Industrial Affairs; Labor, Employment and Health; and Agriculture, Food, Fisheries, Rural Affairs and Planning. Detailed information on reporting requirements will be published in the Official Journal of the French Republic.

The reporting mandate was published February 19, 2012 in Decree 2012-232 (available in French only) (the December 2011 draft decree is available in English). The decree explains that the purpose of the scheme is to improve knowledge of nanomaterials and their uses, to monitor the channels of use, to improve knowledge of the market and the volumes sold and to collect available information on toxicological and eco-toxicological properties.  Data on 2012 nanomaterial use must be submitted by May 1, 2013.

Reporting requirements affect materials that are at least 50 percent comprised of particles with one or more external dimension between 1 nm and 100 nm. When any such material is produced, imported or distributed in quantities of 100 grams, the user must declare identity of the producer, importer, or distributor; identity of the nanomaterial; quantity of nanomaterial produced, distributed or imported; intended uses, and identifying information about the professional users to whom the material has been distributed. Specifics of the reporting requirements include:

  • Identity of the producer, importer, or distributor:
    • business name, official address, VAT number; and
    •  apacity (manufacturer, importer or distributor) and field of activity.
  • Identity of the nanomaterial:
    • chemical identification of the substance,
    • potential presence of impurities,
    • average particle diameter and particle size distribution,
    • specific surface,
    • surface coating, and
    • surface charge.


EPA Denies TSCA Petition for Banning Lead Fishing Tackle


On February 14, 2012, EPA formally announced that it was denying the Center for Biological Diversity’s petition to ban or restrict lead (Pb) in fishing tackle  – fishing weights, sinkers, lures,jigs, etc. – pursuant to section 6 of the Toxic Substances Control Act (TSCA).  The agency stated succinctly:  “After careful review, EPA has determined that, while the petition does provide evidence ofexposure and a risk to waterfowl in some areas ofthe United States, it does not provide a basis for finding that the risk presented is an unreasonable risk for which federal action under section 6(a) of TSCA is necessary to adequately protect against such risks.”  In other words, CBD failed to show that (a) an unreasonable risk of injury was present, and (b) that risk required federal action to correct.   A copy of EPA’s letter is available here, and the Federal Register notice, setting out the complete supporting analysis, is available here.  CBD’s petition is avaialble here.

EPA reasoned that existing federal and state regulatory and educational efforts were sufficiently protective.   “Your petition does not demonstrate why federal action is necessary given the mix of regulatory and education actions state agencies and the Federal Government already are taking to address the impact of lead fishing tackle on local environments. The risk described in the petition does appear to be more prevalent in some geographic areas than others, and the trend over the past decade has been for increasing state and localized federal activity regarding lead in fishing tackle. The petition does not demonstrate that these state and local efforts are ineffective or have failed to reduce the exposure and risks presented to waterfowl in particular.”  In other words, the data simply weren’t there to support the petitioners’ request.

EPA Budget Would Increase Spending on Chemical Assessment and Control

EPA Budget/Chemical Control

According to an EPA press release, today the Obama Administration proposed a FY 2013 budget of $8.344 billion for the agency. The budget is $105 million below the EPA’s enacted level for FY 2012, but it increases spending by $11 million, or approximately 16%, to “protect … Americans from harmful chemicals.”  This increase for chemical assessment and control signals a clear intention to promote regulatory TSCA reform and related efforts in the absence of legislative reform. 

The press release states – “EPA is proposing $68 million, an increase of $11 million from FY 2012, to reduce chemical risks, increase the pace of chemical hazard assessments, and provide the public with greater access to toxic chemical information. Funding will sustain the agency’s successes in managing the potential risks of new chemicals coming into the market and accelerating the progress to help ensure the safety of chemicals on the market that have not been tested for adverse human health and environmental impacts.”

A complete copy of the agency’s budget proposal is available here.

EPA Fines Dover Chemical $1.4 Million for TSCA Violations – But Was EPA Really Looking for an Easy Way to Ban SCCPs?

TSCA Enforcement:

On February 7, 2012, the federal Environmental Protection Agency (EPA) and the Department of Justice (DOJ) announced a settlement with the Dover Chemical Company to resolve alleged violations of the premanufacture notice (PMN) requirements in section 5 of the federal Toxic Substances Control Act (TSCA).  Section 5 requires companies to file a PMN and receive EPA approval before manufacturing a “new” chemical – i.e., one not listed on the TSCA Inventory of existing chemical substances.  EPA accused Dover of failing to file PMNs before manufacturing various chlorinated paraffins at the company’s facilities in Ohio and Indiana.  Although the settlement is noteworthy in demonstrating EPA’s willingness to reinterpret the TSCA Inventory and enforce that reinterpretation, it is perhaps more noteworthy because it suggests EPA is willing to use enforcement as a shortcut to banning substances, as described in the last paragraph of this posting.  A copy of the settlement agreement is available here, and the EPA press release is available here

As part of the settlement, Dover will pay $1.4 million in civil penalties, and the company will stop manufacturing short-chain chlorinated paraffins (SCCPs).  Dover is the only domestic producer of those substances.  In addition, Dover will file PMNs for certain medium-chain and long-chain chlorinated paraffins (MCCPs and LCCPs) in hopes of receiving EPA approval.  Whether the company will receive approval – and if so, under what terms – remains to be seen.

Dover appears to have fun afoul of EPA’s nomenclature guidance and ever-evolving interpretation of the TSCA Inventory.  When EPA first established the TSCA Inventory, the agency arguably required less precision with substance identification.  Over time, however, that has changed.  The agency would certainly disagree, arguing it has been consistent over time, but experience suggests otherwise.  In 1995, EPA published nomenclature guidance – available here – – for complex reaction products, UVCB substances, mixtures, and substances containing varying carbon chain lengths (such as some SCCPs have).  In certain cases, that guidance conflicted with earlier agency statements, requiring some companies to seek Inventory corrections, pursue exemptions or file PMNs for substances they had been manufacturing for years.  Since 1995, EPA has reinterpreted the Inventory status of statutory mixtures and activated phosphors, among others.  It’s almost certain that more changes are on the horizon with the current Administration’s aggressive and expansive use of the TSCA statute.

Perhaps of greatest interest to cynics is the agency’s apparent use of the enforcement mechanism to essentially achieve a ban on SCCPs.  In December 2009, EPA published a Chemical Action Plan for SCCPs , proposing to ban or restrict SCCPs under section 6(a) because the chemicals are thought to be persistent, bioaccumulative, and toxic (PBT), a set of hazard traits that regulatory agencies are particularly concerned about.  The Plan also identified Dover as the only known domestic producer.  According to the settlement agreement, December 2009 was the same month that Dover received a NOV for alleged violations of the PMN requirements for SCCPs and other chemicals.  It is doubtful that this timing was coincidental.  While Dover’s agreement to cease production of SCCPs doesn’t apply to other manufacturers/importers, by shutting down the only domestic production and publicly questioning the Inventory status of many SCCPs, EPA effectively achieved a ban.   This is a cynical conclusion perhaps, but the publicly available facts suggest it’s a reasonable one to draw.  Did EPA initiate enforcement to achieve a result that would have been more difficult to achieve under section 6(a)?  You decide.