For years, scientists struggled to understand the mysterious deaths of coho salmon in urban streams of the US Pacific Northwest, particularly after heavy rainfall. These deaths, known as “Urban Runoff Mortality Syndrome” (URMS), caused up to 90% of coho salmon to die before spawning.
Finally, in December 2020, researchers at the University of Washington identified the culprit: 6PPD-Quinone (6PPD-Q), a chemical degradant of anti-oxidants used in tires. This discovery sparked further investigation into the toxicity of 6PPD-Q on aquatic life, particularly on coho salmon populations in the Pacific Northwest, which is a key issue impacting our region. Previously abundant in BC, coho salmon stocks suffered huge declines in the 1990s, and were listed as endangered in 2002. Their status in BC has begun to improve (threatened since 2016), and they remain essential to many coastal communities and First Nations, providing irreplaceable cultural, commercial, and ecological value.
Recognizing the urgency of this issue in 2021, ALS immediately began to develop a test method to detect 6PPD-Q at extremely low concentrations (0.001 µg/L), utilizing advanced LC-MS/MS technology for definitive identification and measurement. This method utilizes the same technology and method principles as the recently released 6PPD-Q US EPA Draft Method 1634. The release of this method in such a short timeframe by the US EPA is unprecedented and suggests upcoming regulations on 6PPD-Q levels in the United States. Locally, BC ENV has confirmed they are working on water quality objectives for 6PPD-Q. This method is intended to support water quality evaluations in support of important pending US and BC guidelines for 6PPD-quinone.
ALS continues to lead in the analysis of emerging contaminants by enhancing the sensitivity of its 6PPD-quinone method even further, and by expanding its capabilities to include 6PPD, the precursor compound. This advancement supports more comprehensive risk assessments and research, including chronic exposure studies—an area of growing interest in environmental science.