WASHINGTON—The U.S. Tire Manufacturers Association, reacting to a new report linking the deaths of coho salmon fish in the Pacific Northwest with a processing chemical used in tire production, is pledging to work with the study's authors to "advance understanding of these initial findings."
In a prepared statement, the USTMA stresses that the study—issued by researchers at the University of Washington—"consists of preliminary findings that require additional research."
The study, published in the December issue of Science magazine, contends that concentrations of the antioxidant N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine), more commonly called 6PPD, in rivers where salmon spawn are responsible for "unexplained acute mortality" when adult salmon migrate to urban creeks to reproduce.
The issue is particularly acute after rainstorms, the paper's authors contend, when the death rate of salmon spawning upstream soars, according to decades of research into the subject.
The paper's authors link the presence of 6PPD in these rivers and streams to tire treadwear particles that are part of roadway runoff.
"These results reveal unanticipated risks of 6PPD antioxidants to an aquatic species and imply toxicological relevance for dissipated tire rubber residues," the authors state in the paper's abstract.