Importance of Water-Volume on the Release of Microplastic Fibers from Laundry.

The influence of laundry washing parameters on the release of microfibers (MF) from polyester textiles was studied. These fibers are an important type of microplastic pollution. However, the factors which affect MF release during laundry are poorly understood and more rigorous methods for quantifying this release are needed. A novel method was therefore developed using a tergotometer with eight 1000 mL washing vessels and the CIELab color space measure of lightness (L*). L* was related to the mass of released MFs by creating a calibration curve to quantify the amounts of MFs released from textiles during washing. This method was used to investigate the effect of water-volume, agitation, temperature, and duration of the wash on MF release. Counterintuitively, increased water-volume, characteristic of European "delicate" cycles, resulted in the greatest release of MFs. Full-scale testing was then carried out using domestic washing machines with real consumer cycles to determine the effect of cycle type on MF release. In the first wash, delicate wash cycles released 800 000 more MFs (94 mg/kg) per wash than a lower water-volume standard wash and also increased MF release in subsequent washing cycles (P < 0.05). These results indicate that a high water-volume-to-fabric ratio is the most influential factor for MF release, rather than agitation as previously thought. Therefore, consumers can reduce MF release by avoiding high water-volume washes (delicate cycles), transitioning to appliances that use a lower water-volume (North American high-efficiency washing machines), and ensuring that full wash loads are used.

Chemical mapping of xyloglucan distribution and cellulose crystallinity in cotton textiles reveals novel enzymatic targets to improve clothing longevity.

Pilling is a form of textile mechanical damage, forming fibrous bobbles on the surface of garments, resulting in premature disposal of clothing by consumers. However, our understanding on how the structural properties of the cellulosic matrix compliment the three-dimensional shape of cotton pills remains limited. This knowledge gap has hindered the development of effective 'pillase' technologies over the past 20 years due to challenges in balancing depilling efficacy with fabric integrity preservation. Therefore, the main focus here was characterising the role of cellulose and the hemicellulose components in cotton textiles to elucidate subtle differences between the chemistry of pills and fibre regions involved in structural integrity. State-of-the-art bioimaging using carbohydrate binding modules, monoclonal antibodies, and Leica SP8 and a Nikon A1R confocal microscopes, revealed the biophysical structure of cotton pills for the first time. Identifying regions of increased crystalline cellulose in the base of anchor fibres and weaker amorphous cellulose at dislocations in their centres, enhancing our understanding of current enzyme specificity. Surprisingly, pills contained a 7-fold increase in the concentration of xyloglucan compared to the main textile. Therefore, xyloglucan offers a previously undescribed target for overcoming this benefit-to-risk paradigm, suggesting a role for xyloglucanase enzymes in future pillase systems.

From riverbank to the sea: An initial assessment of plastic pollution along the Ciliwung River, Indonesia.

This study presents the first comprehensive analysis of anthropogenic debris on the riverbanks of the Ciliwung River, covering upstream to downstream areas. The mean of debris found in each measurement was 32.79 ± 15.38 items/m2 with a weight of 106.00 ± 50.23 g/m2. Plastic debris accounted for over 50 % of all litter items identified and represents 55 % by weight, signifying a significantly high prevalence compared to global studies examining litter along riverbanks. The majority of the plastics found originated from Single-use applications and were predominantly made from Styrofoam. This investigation demonstrated the importance of actions to reduce single use applications and to improve waste management strategies. This can be achieved through proactive initiatives coupled with adaptable approaches, such as implementing effective urban planning and enhancing waste collection capacity.

Bacterial colonisation of plastic in the Rockall Trough, North-East Atlantic: An improved understanding of the deep-sea plastisphere.

Plastic pollution has now been found within multiple ecosystems across the globe. Characterisation of microbial assemblages associated with marine plastic, or the so-called 'plastisphere', has focused predominantly on plastic in the epipelagic zone. Whether this community includes taxa that are consistently enriched on plastic compared to surrounding non plastic surfaces is unresolved, as are the ecological implications. The deep sea is likely a final sink for most of the plastic entering the ocean, yet there is limited information on microbial colonisation of plastic at depth. The aim of this study was to investigate deep-sea microbial communities associated with polystyrene (PS) and polyurethane (PU) with Bath stone used as a control. The substrates (n = 15) were deployed in the Rockall Trough (Atlantic), and recovered 420 days later from a depth of 1796 m. To characterise the bacterial communities, 16S rRNA genes were sequenced using the Illumina MiSeq platform. A dominant core microbiome (taxa shared across all substrates) comprised 8% of total ASVs (amplicon sequence variant) and accounted for 92% of the total community reads. This suggests that many commonly reported members of the plastisphere are simply opportunistic which freely colonise any hard surface. Transiently associated species consisted of approximately 7% of the total community. Thirty genera were enriched on plastic (P < 0.05), representing 1% of the total community. The discovery of novel deep-sea enriched taxa included Aurantivirga, Algivirga, IheB3-7, Spirosoma, HTCC5015, Ekhidna and Calorithrix on PS and Candidatus Obscuribacter, Haloferula, Marine Methylotrophic Group 3, Aliivibrio, Tibeticola and Dethiosulfatarculus on PU. This small fraction of the microbiome include taxa with unique metabolic abilities and show how bacterial communities can be shaped by plastic pollution at depth. This study outlines a novel approach in categorising the plastisphere to elucidate the ecological implications of enriched taxa that show an affinity for colonising plastic.