Are ‘natural’ textile fibres environmentally benign? A systematic review of chemical processing and microfibre pollution

Abstract Natural and man-made cellulosic textile fibres and microfibres have been viewed as environmentally benign due to their biological origins. This assumption has caused natural and man-made cellulosic microfibres to be overlooked and underrepresented in research despite findings demonstrating their abundance in environmental systems, compared to synthetic, microplastic fibres. This systematic literature review critically examines how natural and man-made cellulosic fibres undergo multiple chemically intensive processing stages within the textile manufacturing processes, resulting in materials that differ substantially from their raw counterparts, exposing critical gaps in understanding across environmental science, toxicology and textile production. These chemical processes influence fibre degradation, increase the potential for pollution adsorption, and contribute to the environmental persistence and impact of microfibre shedding. Across studies, natural and man-made cellulosic microfibres are frequently reported in high abundance in environmental systems yet remain underrepresented in environmental monitoring which predominantly focus on synthetic microplastics. By adopting a textiles perspective, which highlights viewing information through a textile-focussed lens rather than from an environmental science perspective which has dominated this field. This review challenges the assumption that natural and man-made cellulosic microfibres pose no harm to the environment, suggesting that ‘natural’ fibres can cause comparable harm to the environment compared to their synthetic, microplastic counterparts. This demands a reframing of current narratives that position natural and man-made cellulosic textiles as environmentally benign, recognising their potential for environmental harm. The findings further support the inclusion of chemically processed natural and man-made cellulosic microfibres in environmental monitoring, policy and sustainable textile design.