School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.
Departamento de Biología, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Puerto Real, Spain.
PLoS One. 2020 Jun 19;15(6):e0234248. doi: 10.1371/journal.pone.0234248. eCollection 2020.
When clothes are worn and washed, they emit fibres into the ecosystem via discharges of sewage that have been linked to the global dispersion of clothing fibres. Facilities that treat sewage divert some fibres from sewage effluent to sludge, but no current methods of filtration eliminate their environmental release. While filters for washing-machines are sold to consumers with the argument they will reduce the emissions of fibres from clothes to the environment, there is insufficient scientific peer-reviewed evidence assessing their ability to retain fibres from washed clothes and reduce environmental contamination. To improve our understanding and develop more realistic methods to assess the efficiency of filters, we washed replicate cotton and polyester garments in replicate domestic front-loaded washing-machines with and without replicate filters (micro- and milli-meter-sized pores), and then quantified the masses of the fibres retained by the filters and those released in the effluent. Here we show micrometer-sized filters significantly reduced the mass of cotton by 67% (F2,6 = 11.69, P<0.01) compared to effluent from appliances with no filters, whilst filters in general reduced polyester fibres in their effluent by more than 65% (micrometer-sized pores) and 74% (millimeter-sized pores) compared to effluent from appliances with no filters (F2,12 = 5.20, P<0.05). While filters with micrometer-sized pores caught larger masses and total proportions of fibres than filters with millimeter-sized pores, the differences were only significant for the total proportions of cotton (t = 4.799 df = 4, P<0.01). For tests with garments of either types of polymer, the filtered effluent still contained up to a third of the original masses of fibres released from the garments. Given the diversity of clothes, polymers, appliances and filters currently sold to consumers, our work shows the value of increasing the rigour (e.g. more levels of replication) when testing filters and the need for further studies that test an even greater diversity of materials and methods in order to meet the growing demand for knowledge from governments, industry and the public.
当衣物被穿着和洗涤时，它们会通过污水排放将纤维释放到生态系统中，这些污水排放已被证明与服装纤维的全球扩散有关。处理污水的设施会将一些纤维从污水废水中转移到污泥中，但目前没有任何过滤方法可以完全阻止它们释放到环境中。虽然已经向消费者出售了用于洗衣机的过滤器，并声称这些过滤器可以减少衣物纤维向环境中的排放，但目前还没有足够的经过同行评审的科学证据来评估它们从洗过的衣服中截留纤维并减少环境污染的能力。为了提高我们的认识并开发更现实的方法来评估过滤器的效率，我们使用具有和不具有（微孔和毫孔）重复过滤器的重复式家用顶装式洗衣机重复洗涤了重复的棉和聚酯服装，并量化了过滤器截留的纤维和排放到废水中的纤维的质量。在这里，我们发现与没有过滤器的器具相比，微米大小的过滤器可使棉纤维的质量减少 67%（F2,6 = 11.69，P<0.01），而一般来说，过滤器可使聚酯纤维在废水中的减少超过 65%（微孔）和 74%（毫孔）（F2,12 = 5.20，P<0.05），与没有过滤器的器具相比。尽管具有微米大小的孔的过滤器截留的纤维质量和总比例都大于具有毫米大小的孔的过滤器，但仅在棉纤维的总比例方面存在显著差异（t = 4.799 df = 4，P<0.01）。对于由两种类型的聚合物制成的衣物进行的测试，过滤后的废水中仍含有从衣物中释放出的纤维的原始质量的三分之一。鉴于目前向消费者出售的衣物、聚合物、器具和过滤器的多样性，我们的工作表明，在测试过滤器时增加严谨性（例如增加更多的复制水平）的价值，并且需要进行更多的研究，以测试更广泛的材料和方法，以满足政府、行业和公众对知识的不断增长的需求。
