SinS - Abstract

Abstract Title: Determination of tyre-wear contaminants in influent wastewater samples from a high-traffic urban environment by LC-MS/MS and LC-QTOF-MS
Presenter Name: Dr Helena Rapp Wright
Co-authors:Dr Leon Barron
Dr Stephanie Wright
Company/Organisation: Imperial College London
Country: United Kingdom

Abstract Information :

Tyre wear products (TWPs) are micropollutants emitted from tyres. Through ‘runoff’, TWPs can end up in environmental matrices such as riverine surface waters, which may have a negative impact on the environment and possibly human health through exposure routes like drinking water. TWPs can be released to the environment as intact products or through product transformation and degradation from production processes, use and environmental exposure. Recently, some TWPs have been identified in surface waters and drinking water, raising concerns for health. The aim of this study is to monitor three TWPs: 6-PPD quinone, hexamethoxymethyl melamine (HMMM) and 1,3-diphenylguanidine (DPG) in wastewater samples from a highly populated urban environment with a high density of traffic (London, UK). Daily influent wastewater samples were collected as 24-h composite samples for a month in November 2022. They will be analysed quantitatively using different analytical techniques, including a rapid direct injection liquid chromatography-mass spectrometry (LC-MS/MS) method. However, these compounds are an analytical challenge due to their inclusion as an additive in different plastic consumables used in the laboratory, resulting in cross-contamination. Therefore, further analysis is being performed using a LC time-of-flight MS (LC-QTOF-MS) with a mass accuracy of 5 ppm to confirm the presence of these compounds. Preliminary data showed the presence of DPG in 5 samples, resulting in a 100% of frequency of detection. A comparison between both analytical methods, LC-MS/MS and LC-QTOF-MS, will also be performed, as well as a comparison between direct injection and solid phase extraction (SPE), in order to pre-concentrate these analytes in some samples. The presence of other transformation products will also be studied using suspect-screening from a list of TPWs based on literature review and online predictive transformation tools such as BioTransformer 3.0. Occurrence frequency will be established and interpreted to inform comprehensive insight into the regularity and levels of these compounds in London wastewater. This will lead to an estimate of the daily population level (per capita) exposure of TWPs using wastewater-based epidemiology.