Characterizing Recycled Textile Products with LC-HRMS

Scientists from Stockholm University in Stockholm, Sweden used liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) to characterize recycled textile products and detect harmful chemicals. Their findings were published in Analytical Chemistry (1).

Person sorting second hand clothes by size and gender | Image Credit: © Kate - stock.adobe.com

Textile waste is one of the fastest growing waste streams in the United States, with the average consumer throwing away 81 pounds of clothing annually (2). Though 15% of post-consumer textiles are recycled, 85% of used clothing and other textiles end up as waste in landfills and incinerators. As manufacturers adopt circular economy principles to reduce the negative impact of garment production, recycled textiles are quickly becoming available for general use. Today, textile garments can contain up to 98% recycled materials, increasing materials’ life cycles and subsequently greatly reducing their environmental impact. This practice holds various benefits; environmentally, it decreases the number of valuable materials sent to landfills, reduces greenhouse gas emissions, and saves natural resources, while economically, it can reduce disposal costs for local governments and create jobs for reusing and recycling said materials. However, the quality of the source material still has a direct impact on the final product, where the presence of harmful chemicals is of grave concern.

In this study, the scientists created a risk-based suspect and non-targeted screening workflow for detecting, identifying, and prioritizing chemicals present in consumer-based recycled textile products after manufacture and transport. This workflow was applied to characterize 13 recycled textile products from major retail outlets in Sweden. The samples were extracted and analyzed using LC-HRMS. This technique combines the processes of LC, which involve dissolving and pumping a sample through a column containing a stationary phase, with high-resolution mass spectrometry (HRMS), which is attractive for carrying out compound analysis due to its potentially unlimited m/z range with high sensitivity and mass accuracy (3). In both positive and negative ionization mode, 20119 LC-HRMS features were detected and screened against persistent, mobile, and toxic (PMT) chemicals, in addition to other textile-related chemicals. Six substances were matched with PMT substances that are regulated in the European Union (EU). 43 substances were confidently matched with textile-related chemicals typically used in Sweden. To estimate the relative priority score, aquatic toxicity and concentrations were predicted for 7416 features, with tandem mass spectra (MS²) being used to rank the non-targeted features. The top 10 substances were then evaluated due to elevated environmental risks linked to the recycling process and potential end-of-life release.

Through detecting, identifying, and prioritizing numerous restricted and potentially harmful substances, the researchers showed that such chemicals could be present in recycled textile manufacturing, potentially introducing risks to human and environmental health. This study provided a valid methodology for implementing suspect and non-targeted screening methodologies that can help further investigate chemicals detected in textiles, all while more accurately quantifying their concentrations and risk to human and environmental health. Continuous development and manufacture of recycled textiles is integral to the principles of the circular economy, significantly contributing to the reduction of raw materials, waste production, and carbon dioxide emissions to the atmosphere. These goals are vital to human and environmental health and should not be the cost of progress.

References

(1) Szabo, D.; Fischer, S.; Mathew, A. P.; Kruve, A. Prioritization, Identification, and Quantification of Emerging Contaminants in Recycled Textiles Using Non-Targeted and Suspect Screening Workflows by LC-ESI-HRMS. Anal. Chem. 2024, 96 (35), 14150–14159. DOI: 10.1021/acs.analchem.4c02041

(2) Textile Reuse and Recycling. New York State 2024. https://dec.ny.gov/environmental-protection/recycling-composting/more-things-you-can-recycle/textile-reuse-recycling (accessed 2024-9-3)

(3) Aydoğan, C. Chapter 12 - Liquid Chromatography-High Resolution Mass Spectrometry for the Analysis of Bioactive Natural Products. Studies in Natural Products Chemistry 2020, 66, 331–353. DOI: 10.1016/B978-0-12-817907-9.00012-X