Fuzzy Cognitive Mapping (FCM) is a participatory modelling tool used to explore complex systems by facilitating interdisciplinary cooperation and integrating a variety of knowledge systems. Here FCM was used to explore marine microfiber pollution. Through individual interviews with representatives from the research, industry, water and environmental sectors, five stakeholder FCMs were developed and used to produce an aggregated community FCM in a stakeholder workshop. Stakeholder FCMs and the revised community FCM were used to compute how the modelled system reacted to changes under two scenarios developed during the stakeholder workshop; (i) Green Shift and (ii) increased textile consumption and production. Significant differences were observed in scenario results from the stakeholder-based models and the community-based model. For societal challenges characterized by unknowns around the problem and potential solutions, inclusion of a variety of knowledge systems through FCM and deliberation processes contribute to a more holistic picture of the system and its uncertainties. | publishedVersion

Per- and polyfluoroalkyl substances (PFASs) are used in specialty/functional textiles to impart oil, water, and stain repellency. Little is known, however, with regard to the occurrence of PFASs in textiles including infant clothing. In this study, 13 perfluoroalkyl acids (PFAAs), comprising four perfluoroalkyl sulfonic acids (PFSAs; C4–C10) and nine perfluoroalkyl carboxylic acids (PFCAs; C4–C12) were determined in 160 textile samples collected from the United States. Two extraction methods, one involving a simple solvent extraction (i.e., before oxidation) and the other with an oxidative treatment (i.e., after oxidation) of textile extracts, were used. The sum concentrations of 13 PFAAs (i.e., ∑PFAA) in textile extracts before oxidation ranged from <LOD to 63.7 μg/m² (<LOD–285 ng/g), with a mean value of 3.18 μg/m² (14.2 ng/g). ∑PFAA concentrations were the highest in flame retarded textiles (n = 23; mean: 13.3 μg/m²; 59.4 ng/g), followed by water repellent textiles (n = 56; 2.88 μg/m²; 12.9 ng/g) and infant clothes (n = 81; 0.521 μg/m²; 2.33 ng/g). C4–C10 PFCAs accounted for at least three-quarters of the ∑PFAA content in our textile samples. Textile extracts analyzed after oxidative treatment exhibited ∑PFAA concentrations 10-fold higher than those in extracts analyzed prior to oxidation, which suggested that PFAA precursors are used in textiles. Precursors that generated C4–C5 PFCAs, upon oxidation, were more prevalent than those that yielded PFOA. The calculated dermal exposure doses in infants of PFAAs present in clothes were at least 1–2 orders of magnitude below the reference doses proposed by the United States Environmental Protection Agency. This is the first time that the oxidative treatment was applied in the analysis of PFASs in textiles, and our results suggest the existence of PFCA precursors in textiles.

Microfiber is a subgroup of microplastics and accounts for a large proportion of microplastics in aquatic environment, especially in municipal effluents. The purpose of the present study was to quantify microfiber shedding from three most populate synthetic textile fabrics: polyester, polyamide, and acetate fabrics. The results showed that more microfibers were released after washing with a pulsator laundry machine than a platen laundry machine. The greatest number of microfibers was released from acetate fabric, which was up to 74,816 ± 10,656 microfibers/m2 per wash, although microfibers were shed from all materials. Moreover, an increasing trend was found in the number of microfibers shedding from synthetic fabrics with the washing temperature increasing, and greater microfiber release occurred when washing fabrics with detergent rather than with water alone. The lint filter bag equipped with the pulsator laundry machine retained the longer microfibers (>1000 μm), but not the shorter microfibers (<500 μm) instead of releasing into the drainage system. Our data suggested that microfibers released during washing of synthetic fabrics may be an important source of microfibers in aquatic environment due to the increasing production and use of synthetic fabrics globally. Thus, more efficient filtering bags or other technologies in household washing machines should be developed to prevent and reduce the release of microfibers from domestic washing.

The influence of common textile finishes on cotton fabrics on the generation of microfibers during laundering was assessed. Microfiber release was determined to be in the range of 9000–14,000 particles per gram of cotton fabric. Cotton knitted fabrics treated with softener and durable press generate more microfibers (1.30–1.63 mg/g fabric) during laundering by mass and number than untreated fabric (0.73 mg/g fabric). The fabrics treated with softener generated the longest average microfiber length (0.86 mm), whereas durable press and water repellent treatments produced the shortest average microfiber length (0.62 and 0.63 mm, respectively). In general, the changes in the mechanical properties of the fibers and fabrics due to the finishing treatments are the main factor affecting the microfiber release. The abrasion resistance of the fabrics decreases for durable press treatments and water repellent treatments due to the brittleness in the structure originated by the crosslinking treatment. In the case of the softener treatment, the fabric surface is soft and smooth decreasing the friction coefficient between fibers favoring the fibers loosening from the textile and resulting in a high tendency for fuzz formation and microfiber release. These findings are useful for the textile industry in the design and selection of materials and treatments for the reduction of synthetic or natural microfiber shedding from textiles.

The presence and biodegradability of textile microfibers shed during laundering or use is an important environmental issue. In this research, the influence of common textile finishes on the persistence of cotton fibers in an aerobic aquatic environment was assessed. The biodegradation of cotton knitted fabrics with different finishes, silicone softener, durable press, water repellent, and a blue reactive dye was evaluated. The rate of biodegradation decreased with durable press and water repellant finishing treatments. In terms of the final extent of biodegradation, there was no significant difference between the samples. All samples reached more than 60% biodegradation in 102 days. The biodegradation rates were in agreement with observed trends of the same samples for cellulase mediated hydrolysis and cellulase adsorption experiments, indicating the finishes impact the initial adsorption of enzymes excreted by the microorganisms and the initial rates of biodegradation, however despite this the cellulosic material maintains its biodegradability.

The effect of fiber type (cotton, polyester, and rayon), temperature, and use of detergent on the number of microfibers released during laundering of knitted fabrics were studied during accelerated laboratory washing (Launder-Ometer) and home laundering experiments. Polyester and cellulose-based fabrics all shed significant amounts of microfibers and shedding levels were increased with higher water temperature and detergent use. Cellulose-based fabrics released more microfibers (0.2–4 mg/g fabric) during accelerated laundering than polyester (0.1–1 mg/g fabric). Using well-controlled aquatic biodegradation experiments it was shown that cotton and rayon microfibers are expected to degrade in natural aquatic aerobic environments whereas polyester microfibers are expected to persist in the environment for long periods of time.

Fuzzy Cognitive Mapping (FCM) is a participatory modelling tool used to explore complex systems by facilitating interdisciplinary cooperation and integrating a variety of knowledge systems. Here FCM was used to explore marine microfiber pollution. Through individual interviews with representatives from the research, industry, water and environmental sectors, five stakeholder FCMs were developed and used to produce an aggregated community FCM in a stakeholder workshop. Stakeholder FCMs and the revised community FCM were used to compute how the modelled system reacted to changes under two scenarios developed during the stakeholder workshop; (i) Green Shift and (ii) increased textile consumption and production. Significant differences were observed in scenario results from the stakeholder-based models and the community-based model. For societal challenges characterized by unknowns around the problem and potential solutions, inclusion of a variety of knowledge systems through FCM and deliberation processes contribute to a more holistic picture of the system and its uncertainties.

Microfibers are a common type of microplastic. One known source of microfibers to the environment is domestic laundering, which can release thousands of fibers into washing machine effluent with every wash. Here, we adapted existing methods to measure the length, count and weight of microfibers in laundry effluent. We used this method to test the efficacy of two technologies marketed to reduce microfiber emissions: the Cora Ball and Lint LUV-R filter. Both technologies significantly reduced the numbers of microfibers from fleece blankets in washing effluent. The Lint LUV-R captured an average of 87% of microfibers in the wash by count, compared to the Cora Ball which captured 26% by count. The Lint LUV-R also significantly reduced the total weight and average length of fibers in effluent. While further research is needed to understand other sources of microfiber emissions, these available technologies could be adopted to reduce emissions from laundering textiles.

Dimethylformamide (DMF) is a broad solvent used in the production of synthetic leather. Decades of year's research have been focused on workers in leather factories suffering from the release of DMF. However, little attention was paid on general population. Here, we examined the relationship between consistent DMF exposure and annual hospitalizations of local residents in Longwan, China, in 2008. We found a positive correlation with a relative risk (RR) increase of 1.110 for total hospitalizations. When the data were stratified by sex, we observed a higher correlation for female hospitalizations than for male hospitalizations, with RR values of 1.55 and 1.084, respectively. This might be attributed to the differences in genotypes of oxidant enzyme between gender. The significance of the correlations did not disappear after we excluded the extreme value of DMF or adjusted for SO₂, NO₂, and PM₁₀. Population living near the leather factory has experienced almost constant DMF exposure, and real concern should be raised regarding such exposure. Governments should take responsibility for the protection of not only occupational workers but also residents, especially women.

An environmentally friendly and inexpensive substitute to the widely used poly(vinyl alcohol) (PVA) has been developed from soy proteins for textile warp sizing. Textile processing is the major source of industrial water pollution across the world, and sizing and desizing operations account for nearly 30 % of the water consumed in a textile plant. PVA is one of the most common sizing agents used for synthetic fibers and their blends due to PVA's easy water solubility and ability to provide desired sizing performance. However, PVA does not degrade and is a major contributor to pollution in textile effluent treatment plants. Although considerable efforts have been made to replace PVA with biodegradable sizing materials, the performance properties provided by PVA on synthetic fibers and their blends have been unmatched so far. Soy proteins are inexpensive, biodegradable, and have been widely studied for potential use in food packaging, as resins and adhesives. In this research, the potential of using soy proteins as textile sizing agents to replace PVA was studied. Polyester and polyester/cotton rovings, yarns, and fabrics sized with soy protein showed a considerably better improvement in strength and abrasion resistance compared to commercially available PVA-based size. Soy protein size had a 5-day biochemical oxygen demand /chemical oxygen demand ratio of 0.57 compared to 0.01 for PVA indicating that soy protein sizes were easily biodegradable in activated sludge. The total and ammonia nitrogen released from the proteins also did not adversely impact the biodegradability. Good sizing performance and easy biodegradability demonstrate that soy protein-based sizes have potential to replace PVA-based sizes leading to substantial benefits to the textile industry and the environment.