We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Mitigation of microplastic-associated emerging pollutants by chlorination using field-collected microplastic: Antimicrobial-resistant genes and pathogens
Summary
This study investigated whether chlorination — the most common water disinfection method — can kill the antibiotic-resistant bacteria and genes that colonize microplastics in the environment. Chlorine treatment reduced antibiotic resistance genes on microplastics by up to 99.7%, but the thick biofilms on plastic surfaces shielded interior bacteria, limiting full disinfection. A concerning side effect was that chlorine caused microplastics to fragment into even smaller particles under 100 micrometers, potentially increasing their biological uptake and spreading disinfection-resistant genetic material further.
The ubiquity of microplastics (MPs) in aquatic environments has raised significant concerns regarding their roles as vectors for antibiotic-resistance genes (ARGs) and antibiotic-resistant pathogens (ARPs). This study investigated the mitigation of ARGs and ARPs associated with field-collected MPs through chlorination using free available chlorine (FAC) at varying concentrations. FAC effectively reduced the absolute abundance of ARGs on MPs by up to 99.69 %, although the relative abundance of certain ARGs persisted or increased after treatments. Results revealed that the three-dimensional structure of biofilms on MPs significantly influenced FAC efficacy, with interior biofilm bacteria demonstrating greater resistance than outer biofilm. Additionally, FAC induced fragmentation of MPs, particularly increasing the proportion of particles smaller than 100 μm. Notably, ARGs such as sul1 and ermB showed substantial reductions in absolute abundance, whereas ermC and sul2 exhibited less reduction, highlighting the complexity of disinfection in MP-associated biofilms. These findings underscore the need for optimizing disinfection strategies to mitigate ARG dissemination and address environmental risks posed by MPs in wastewater effluents.