Environmental Impact of Nanosilver on the Biodegradability of Polylactic Acid Nonwovens
摘要
The integration of silver nanomaterials into the textile industry has gained attention due to their strong antimicrobial properties. However, concerns remain regarding their environmental impact, particularly at the end of the product life cycle. This study investigates the effect of silver chloride nanoparticles (AgCl NPs) on the biodegradability of polylactic acid (PLA) nonwoven textiles used as disinfectant wipes, considering ageing via standardised washing and abrasion tests. AgCl NPs were applied to nonwovens using the pad-dry-cure method. Their presence and distribution were characterised using FESEM, EDX, DLS, and FTIR-ATR. Biodegradability was assessed by measuring carbon dioxide (CO2) evolution in a controlled soil environment. Antibacterial activity was evaluated using 3M™ Aerobic Count (AC) Petrifilm™ Plates, applied to both textiles and post-biodegradation soil. Ecotoxicity was evaluated via an indirect approach based on Lens culinaris germination and growth, following OECD Test Guideline 208, using soil samples from the biodegradation process. The findings reveal that AgCl NPs hinder PLA biodegradation, significantly reducing CO2 production and indicating bacterial inhibition. Ageing further intensified this effect by concentrating AgCl NPs on the fibre surface, enhancing antibacterial activity while reducing particle adhesion. Although no acute ecotoxicity was detected in plant-based assays, a decline in aerobic bacterial diversity was observed in soils exposed to AgCl NPs-treated samples. These results underscore the need to balance the antibacterial benefits of AgCl NPs with their environmental impact, particularly in products that may contribute to solid waste accumulation. Future research should focus on sustainable alternatives that maintain antibacterial efficiency while ensuring eco-friendly disposal.
Graphical Abstract