US EPA

In September 2013, EPA announced the availability of the final report, Comprehensive Environmental Assessment Applied to Multiwalled Carbon Nanotube Flame-Retardant Coatings in Upholstery Textiles: A Case Study Presenting Priority Research Gaps for Future Risk Assessments. This final report presents a case study of multiwalled carbon nanotubes (MWCNTs); it focuses on the specific example of MWCNTs as used in flame-retardant coatings applied to upholstery textiles.

This case study is organized around the comprehensive environmental assessment (CEA) framework, which structures available information pertaining to the product life cycle, environmental transport and fate, exposure-dose in receptors (i.e., humans, ecological populations, and the environment), and potential impacts in these receptors. A group of experts representing multiple disciplines and multiple sector perspectives used an earlier draft of the case study in conjunction with a structured workshop process to identify and prioritize research gaps that, if pursued, could inform future MWCNT assessment efforts.

The final report is not a health, risk, or exposure assessment and as such does not draw conclusions about potential risks, or present an exhaustive review of the literature. Rather, it presents the MWCNT research priorities that experts identified in this application of CEA in order to aid research planning throughout the scientific community. The outcomes of these research efforts may subsequently inform long-term MWCNT assessments.

Engineered nanoscale materials (nanomaterials) are generally described as having at least one dimension between 1 and 100 nanometers (nm). Due to their small size, nanomaterials often have novel properties that confer different potential benefits and risk compared to their non-nano form. The assessment of such risks and benefits requires information, but given the relatively new state of nanotechnology, much remains to be learned about the characteristics and effects of nanomaterials.

The external review draft of this case study provided a starting point for a workshop process that engaged experts with diverse technical backgrounds (e.g., toxicology, polymer science, environmental fate and transport) and sector perspectives (e.g., industry, academia, government). Information on a historically used flame-retardant (decabromodiphenyl ether, or decaBDE) was included in the draft case study document as a more robust dataset to help experts identify potential key data gaps in assessing risks from MWCNTs. Experts used the draft case study document to identify and prioritize research gaps that could support future assessment and risk management efforts for MWCNTs. This prioritization took place through a structured decision process that allowed each expert to have equal input on the outcome. RTI International, an EPA contractor, independently conducted this structured workshop process through the use of web-based tools and a face-to-face workshop.

Subsequently, EPA revised the draft case study document to highlight the priority research areas identified in the structured workshop process, as well as incorporate valuable feedback from public commenters and experts participating in the RTI workshop process. These revisions included streamlining the document by highlighting how decaBDE information could inform MWCNT research planning and moving details on decaBDE to an appendix. The revised case study (i.e., peer review draft) then underwent an independent, external letter peer review. EPA revised the peer review draft in response to reviewer comments to develop the final case study document.

The research priorities presented in the final report, as well as those identified through similar applications of CEA to nanomaterials (see links below), are intended to inform ongoing research planning for nanotechnology in the general scientific community as well as at the EPA.

This document seeks to identify what is known and unknown related to assessing the health and environmental implications of a nanomaterial; in this case multiwalled carbon nanotubes (MWCNTs) used in flame-retardant coatings applied to textiles.

U.S. EPA. Comprehensive Environmental Assessment Applied To Multiwalled Carbon Nanotube Flame-Retardant Coatings In Upholstery Textiles: A Case Study Presenting Priority Research Gaps For Future Risk Assessments (Final Report). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-12/043F, 2013.