As one of the top global industries, textile manufacturing utilizes several thousands of industrial chemicals, many of which end up in the finished garments. These residues constitute a widespread, possibly hazardous, exposure of the general population, yet the long-term health effects remain largely unknown. Skin allergy - a life-long, incurable condition – is one health effect of repeated skin exposure to one or several chemicals. Among the Western population, textile allergy is estimated to have a prevalence of around 1%.

Fast-fashion trends make the chemical content in everyday textile apparel hard to predict, as non-regulated chemicals are rapidly introduced into production. Only a tiny fraction of the used chemicals is hitherto regulated, and there is a lack of oversight regarding the content in everyday garments. A recently introduced EU legislation concerning handling textile waste motivates the development of alternative recycling methods for worn-out textile apparel. Upcycling methods are also important to reduce the environmental burden from incineration and landfilling.

This thesis focuses on developing analytical tools for the quantitative chemical screening of textiles. A novel, fully automated analytical methodology based on thermal desorption - gas chromatography-mass spectrometry (ATD-GC/MS) was developed for polyester, synthetic polyester blends, and cotton, constituting at least 75% of the retail market. The method is especially suitable for detecting semi-volatile compounds capable of skin permeation. Recently, the method was proposed for evaluation as a potential EU standard. Ultimately, the method could help ensure regulatory compliance within the textile industry. 

In addition, a high-resolution mass spectrometry workflow was developed to investigate the fate of hazardous substances during the upcycling of polycotton waste into cellulose nanocrystals. Most hazardous textile chemicals were found to remain in the polyester, while the upcycled product contained much less contaminants. Chemical release into waste streams is correlated with solubility under acidic conditions, highlighting target compounds for removal during upscaling.

Together, the developed methods contribute to a robust analytical toolbox with the potential to improve chemical oversight in textiles, support regulatory expansion, and promote safer, more sustainable fashion.