TEACHING MATERIALS for researchers/teachers trainees

TOXICITY OF NANOMATERIALS IN TEXTILES

Nowadays, the release of various nanoparticles to the environment is of more a concern. Huge problem are nanoparticles of Ag which are toxic to aquatic animals, including fish, crayfish, and plankton. Furthermore, the antibacterial properties of Ag NPs might disrupt the bacterial habitat in sewage treatment plants.

Nanowashing machines were shown to release Ag in effluent at a concentration of ∼11 μg L⁻¹. Recent life cycle assessments involved comparing environmental benefits and negative effects of nano Ag T-shirts with conventional textiles treated with triclosan (a biocide), see below figure.

                                                            Fig. 3.3.1. Life cycle stages of nano Ag T-shirt with system boundaries

According to data, climate footprints of the manufacturing of nanoAg T-shirt were 2.70 kg of CO₂-equiv for flame spray pyrolysis and 7.67−166 kg of CO₂-equiv for plasma polymerization with Ag cosputtering. On the other side, conventional T-shirts produced by triclosan had emissions of 2.55 kg of CO₂-equiv. Additionally, the toxic releases from washing and disposal stages had minor relevance.

Limitation of these studies was that variation in Ag release rates was not taken into consideration.  Also, current life cycle impact assessment methods do not distinguish colloidally bound phases of metals. Until now, the life cycle assessments took into account only NP form. Considering other forms of nanomaterials, such as ionic forms, agglomerated forms, and oxidized forms, will provide improved of life cycle assessments. While these assessments provide an estimated effect of nanomaterials on the environment, public awareness holds importance in washing practices.  

Efficient washing procedures using tumblers less and operating the washing machine at lower temperatures with appropriate detergents may reduce the environmental impact. The increase in the awareness for recycling rate of NP-embedded textiles may decrease the carbon footprint. The development of improved life cycle assessments will allow comparing nanoengineered textiles with conventional products in the market to prevent negative environmental consequences.

Source:  Prospective Environmental Life Cycle Assessment of Nanosilver T-Shirts. Environ. Sci. Technol. 2011, 45, 4570−4578.

Fashionable functional products transcending the traditional functions of fabric are highly desirable. Growth in the fashion and entertainment industry is expected to contribute to overall market growth. Additionally, the demand from the sports and fitness sector has increased due to growing awareness about healthy lifestyles. End users participating in extreme sports, running, and skiing have also contributed to the demand for smart textiles. To increase the competitiveness with respect to Asia, the European Union has created initiatives for promoting incentives. 

Today, global customers are willing to pay a premium price for functional garments. However, in another market segment, the target customer may demand affordable functional textiles. One possible reason for the interest in innovation in textiles is that porous materials, synthetic microfibers, and membranes used commercially over the past 30 years have been commodified. This may be attributed to the accessibility of blockbuster technologies due to patent expirations. The commodification subsequently reduced the profit margin and market share. As a result, companies in the textile industry need to offer competitive advantage through innovation by either enhancing performance or reducing the production cost.

Source: ACS Nano 2016, 10, 3042−3068, DOI 10.1021/acsnano.5b08176

Facts:

• In parallel to the development of nanotextiles, life cycle assessments and toxicity of released nanomaterials from textiles are being critically evaluated. 
• Nanotechnology-based products will continue to emerge with new applications; manufacturers and regulatory agencies must ensure that these technologies will not have a negative effect on human health and the planet during their manufacture and life cycle. 
• The textile industry is under scrutiny due its impact on climate change. 
• Today, textiles and apparel account for ∼10% of the total carbon emissions. 17−20% of industrial water pollution originates from dyeing and finishing agents in the textile industry, negatively affecting people inhabiting regions around textile production plants, particularly in the developing world. 
• Dyes and fixing agents (e.g., chromium) in textile manufacturers and tanneries are major pollutants, particularly in Southeast Asia. 
• Hence, the effect of nanoproducts on the production dynamics and pollution remains questionable.
• Growing concerns among customers has begun forcing the manufacturers to reduce the environmental impact of their production methods, which will also involve the use of nanomaterials. 
• Social awareness among customers has probed companies to invest in corporate social responsibility to offer environmentally sustainable products with reduced carbon footprints. 
• These trends in customer behavior and climate change will include the use of nanotextiles, which need to be climate neutral and recyclable aimed at reducing greenhouse emissions. 
• Nanotechnology will undoubtedly evolve textiles, transcending style changes to shape the next big concept: the connected couture.

Generally, environmental pollution in textile wet processes can be reduced by four main ways:

Examples of Good practices:

    

        Source: https://arctic-flamingo.com/econyl-yoga-leggings/

ECONYL® 100% recycled PA, tt. Aquafil have potential in architecture, design, automotive industry and carpet industry.

• Lenzing™ Refibra™ fibre from cotton as waste raw materials

   

Source: https://www.sustainabletextiles.club/lenzing-refibra

Source: https://syvendeswimwear.com/pages/econyl

👉 Critical Review on Sustainability in Denim: A Step toward Sustainable Production and Consumption of Denim

                                                                    

Here you can find new article as critical review on sustainability of denim:
The exponential development in knowledge on the health and environmental concerns linked to conventional denim processing is directly responsible for the continuous increase in demand for the exploitation of sustainable denim. Research is essential to explore alternative methods to reduce the environmental impact caused by these industries. This review examines the many sustainable ways to produce denim, keeping in mind the problems that the denim industry is now facing in finding alternatives to conventional manufacturing practices. The most current advancements in environmentally friendly dyeing techniques for denim have been extensively discussed. These processes include the production of indigo from bacteria as well as different dyeing processes, such as digital spray, microbially assisted dyeing, and foam dyeing denim with indigo. In addition, this review covers the many environmentally friendly finishing methods for denim garments, such as ozone fading, e-flow, enzyme-based bleaching, water, laser fading, and so on. Finally, it is described how the chemical and mechanical processes used to finish denim might affect the amount of microplastics and microfibers released from the denim garment during domestic washing. As a result, the content presented in this review aims to address the importance of sustainable denim processing, that is, something that can be rethought, reevaluated, renewed, and restructured within the scope of conventional denim processes, while taking eco-responsible solutions for increased environmental sustainability into account (Critical Review on Sustainability in Denim: A Step toward Sustainable Production and Consumption of Denim | ACS Omega).

                              Table: Various Sustainable Decoloration Methods for Denim Processing

                           

Source: https://pubs.acs.org/doi/10.1021/acsomega.2c06374

Source: Use of Ozone in the Textile Industry, DOI: http://dx.doi.org/10.5772/intechopen.81774

Source: Benli H, Bahtiyari Mİ. Combination of ozone and ultrasound in pretreatment of cotton fabrics prior to natural dyeing. Journal of Cleaner Production. 2015;89:116-124. DOI: 10.1016/j.jclepro.2014.11.007