Evaluating the use of alternatives assessment to compare bulk organic chemical and nanomaterial alternatives to brominated flame retardants

Alternatives assessment (AA) provides a framework for selection of safer substitutes for problematic chemicals. This study assesses alternatives for flame retardants (FR) in electrical and electronic equipment (EEE), including two common brominated FR, decabromodiphenyl ether (deca-BDE) and tetrabromobisphenol A (TBBPA). Although deca-BDE is restricted in the EU and undergoing phase-out in the US, TBBPA is still widely used. However, concerns about potential hazards are driving a search for halogen-free alternatives. Nonhalogenated organic chemical alternatives (e.g., phosphorus-based FRs) as well as minerals (e.g., montmorillonite) and nanomaterials (e.g., carbon nanotubes) have been proposed, yet it is unclear whether current frameworks can be used to systematically compare such heterogeneous alternatives. This study aims to (i) identify technologically and economically viable alternative FRs and (ii) evaluate each under the current AA frameworks, to (iii) elucidate challenges and shortcomings to adopting proposed alternatives. Uncertainties persist regarding the hazards of both novel nanomaterials and traditional chemicals. Historically, problematic chemicals undergoing restriction have been substituted with another chemical providing, at best, marginally reduced hazard, a problem that AA was, in part, developed to solve. Its successful implementation will depend on our ability to reduce hazard during the design stage, which is currently precluded by the "commercially available and economically viable" emphasis of AA. Methods are needed to bridge AA with sustainable chemical design to prevent it from becoming a tool of only incremental improvement.

Duke Scholars

Author Leanne Gilbertson Civil and Environmental Engineering