Nontarget and Suspect Screening Analysis of Samples Containing Compounds Derived from Tire Rubber

New Organic Monitoring Techniques (Session 2)
Oral Presentation

Prepared by K. Oetjen1, S. Roberts2, M. Noestheden3
1 - SCIEX, 111 Snowmass Place, Longmont, CO, 80504, United States
2 - SCIEX, 6390 Joyce Dr # 100, Golden, CO 80403, Golden, Colorado, 8040, United States
3 - SCIEX, 6390 Joyce Dr # 100, Golden, Colorado, 80403, United States


Contact Information: [email protected]; 845-705-5573

ABSTRACT

Recycled tire products pose risk to both the environment and human health. 1,2 A recent study by Tian et al. (2021) identified the presence of a quinone transformation product of N-(1,3- dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD), as a potential source of acute mortality in U.S. Pacific Northwest Coho salmon (Oncorhynchus kisutch). 2 6PPD is used as a tire rubber antioxidant and it, along with its transformation product 6PPD-quinone, were found in roadway runoff and stormwater samples at toxic concentrations.2 While roadway runoff is one pathway for tire related compounds to enter the environment, there are many other ways these compounds can be introduced. Recycled tire products have been used for a variety of purposes including landscaping, rubberized asphalt, and as a synthetic alternative for turf fields. These synthetic turf fields have been installed in the United States since the 1960s and currently, there are 12,000-13,000 synthetic turf fields nationally, with 1,200 – 1,500 new fields being installed each year. According to the United States Environmental Protection Agency (US EPA), 6PPD was observed in nontargeted analysis of both recycling plant and synthetic turf field samples with relatively high response area counts, along with many other compounds that were tentatively identified or not identified. Due to the wide variety of compounds present in tire derived samples and the presence of thousands of unknown features, comprehensive screening methods and comprehensive data collection methods detection are required. This study uses the X500B QTOF system and a data independent acquisition approach (SWATH acquisition) to acquire high-quality, high resolution MS/MS data to screen for both known-unknowns and perform nontargeted analysis. In the tire derived sample, 17 amide compounds were identified in addition to 6PPD-quinone. Of these 17, several compounds were not found in mass spectral databases or in the literature, as they are likely impurities created in the tire production process.