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Recycling and reusing items is generally accepted as the “right” thing to do. But what if there were unintended, negative consequences to recycling? For example, old car tires are often ground down and reused for synthetic turf, with roughly 40,000 tires used per field.1 However, car tires contain the chemical 6PPD,5 which is converted by ozone to a quinone compound 6PPD-quinone (6PPD-Q) and enters river systems where it is toxic to coho salmon. In addition, some studies have detected per- and polyfluorinated alkyl substances (PFAS)— the” forever chemicals”—in artificial turf,1,4 which means it may be a source of PFAS found in nearby water supplies and potentially in drinking water.
Why are PFAS in artificial turf?
When artificial turf was first introduced, it was thought to have a wide variety of environmental benefits, including reducing water consumption, mowing costs and the need to use pesticides.1 Now, with the risk of PFAS leaching into waterways, it is starting to look like the opposite might be true.
While it may seem surprising that PFAS have been detected in artificial turf, they are used in two separate steps during the manufacture of turf.4 First, PFAS are used during the plastic extrusion stage to help the plastic pass through the molds without getting stuck. Second, they may be used as additives in the plastics to impart beneficial properties such as decreasing plastic reactivity and permeability.
Relatively little is known about PFAS in artificial turf, but a study from Stockholm University in Sweden did reveal some insight.4 The researchers quantified three unique types of PFAS in the turf tested: total fluorine (TF), extractable organic fluorine (EOF) and targeted PFAS compounds. High levels of TF were detected in the artificial turf, but only low concentrations of EOF and individual PFAS compounds were found. Overall, these results implied that PFAS were unlikely to leach from the turf, suggesting minimal environmental impact. However, the researchers noted that very little is known about what happens when artificial turf is disposed of in landfills.
What is 6PPD-Q?
The chemical 6PPD is added to tires to prevent their breakdown and ensure vehicle and passenger safety. It is an antioxidant that protects tire rubber from the sun, oxygen and extreme temperatures.3 However, ozone in the atmosphere reacts with the 6PPD in tires and forms the quinone species 6PPD-Q.5
When friction occurs between tires and the road, tiny tire particles are released and ultimately pollute local water systems. Once in lakes, streams and rivers, 6PPD-Q may leach from these tire particles and be absorbed by aquatic organisms. In addition, when tires become significantly worn and removed from vehicles, they are often recycled into turf beads and used in products such as turf fields.2 Runoff from synthetic turf fields may contain low concentrations 6PPD-Q, which is known to be toxic to freshwater salmon,3 other fish species and possibly other organisms.
How can we detect these contaminants?
Access a quantitative assessment of 6PPD-Q using the X500B QTOF system paired with SCIEX OS software and discover how mass spectrometry can be used to quantify other contaminants in our environment.
References:
- Toxic PFAS Chemicals Found in Artificial Turf. Sharon Lerner, The Intercept, 2019. https://pfasproject.com/2019/10/09/toxic-pfas-chemicals-found-in-artificial-turf/
- Nontarget and suspect screening analysis of samples containing compounds derived from tire rubber. SCIEX, RUO-MKT-02-13659-A. https://sciex.com/tech-notes/environmental-industrial/industrial/nontarget-and-suspect-screening-analysis-of-samples-containing-c
- 6PPD-Quinone, Eurofins. https://www.eurofinsus.com/environment-testing/services/specialty-services/6ppd-quinone/
- Lauria, M.Z. et al. Widespread Occurrence of Non-Extractable Fluorine in Artificial Turfs from Stockholm, Sweden. Environ. Sci. Technol. Lett. 2022 9 (8), 666-672. https://pubs.acs.org/doi/10.1021/acs.estlett.2c00260
- Tire rubber-derived 6-PPD quinone: Testing for a newly discovered environmental contaminant. SCIEX, RUO-MKT-11-13424-A. https://sciex.com/content/dam/SCIEX/videos/environmental/trendsetters-tire-rubber-derived-6-ppd-quinone-testing-for-a-newly-discovered-environmental-contaminant.mp4
RUO-MKT-18-15055-A
Very interesting commentary – gives one pause when you think about all the places we might encounter these forever chemicals.