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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Insights into the release of triclosan from microplastics in aquatic environment assessed with diffusive gradient in thin-films
AU - Liu, Si-Si
AU - Jia, Yu-Wei
AU - Guo, Xiao-Yuan
AU - Zhao, Jian-Liang
AU - Gao, Yue
AU - Sweetman, Andy J
AU - Ying, Guang-Guo
AU - Xu, Li
AU - Tu, Chen
AU - Chen, Chang-Er
PY - 2023/7/15
Y1 - 2023/7/15
N2 - Organic chemicals associated with microplastics (MPs) can be released and thus pose potential risks during weathering processes. However, the thermodynamics and kinetics of their release processes still need to be better understood. Herein, the adsorption and desorption kinetics of triclosan on polystyrene (PS) and polyvinyl chloride (PVC) were investigated by using both batch experiments and diffusive gradients in thin-films (DGT) technique. The pseudo-second-order model fitted the data best, implying that both intraparticle diffusion and external liquid film diffusion influence the adsorption and desorption processes. DGT continuously accumulated triclosan from MP suspensions but slower than theoretical values, indicating some restrictions to desorption. The DGT-induced fluxes in Soils/Sediment (DIFS) model, employed to interpret DGT data, gave distribution coefficients for labile species (K ) of 5000 mL g (PS) and 1000 mL g (PVC) and the corresponding response times (T ) were 10 s and 1000 s, respectively. Higher K but smaller T for PS than PVC showed that more triclosan adsorbed on PS could be rapidly released, while there were some kinetic limitations for triclosan on PVC. A novel finding was that pH and ionic strength individually and interactively affected the supply of triclosan to DGT. This is the first study to quantify interactions of organics with MPs by using DGT, aiding our understanding of MPs' adsorption/desorption behavior in the aquatic environment.
AB - Organic chemicals associated with microplastics (MPs) can be released and thus pose potential risks during weathering processes. However, the thermodynamics and kinetics of their release processes still need to be better understood. Herein, the adsorption and desorption kinetics of triclosan on polystyrene (PS) and polyvinyl chloride (PVC) were investigated by using both batch experiments and diffusive gradients in thin-films (DGT) technique. The pseudo-second-order model fitted the data best, implying that both intraparticle diffusion and external liquid film diffusion influence the adsorption and desorption processes. DGT continuously accumulated triclosan from MP suspensions but slower than theoretical values, indicating some restrictions to desorption. The DGT-induced fluxes in Soils/Sediment (DIFS) model, employed to interpret DGT data, gave distribution coefficients for labile species (K ) of 5000 mL g (PS) and 1000 mL g (PVC) and the corresponding response times (T ) were 10 s and 1000 s, respectively. Higher K but smaller T for PS than PVC showed that more triclosan adsorbed on PS could be rapidly released, while there were some kinetic limitations for triclosan on PVC. A novel finding was that pH and ionic strength individually and interactively affected the supply of triclosan to DGT. This is the first study to quantify interactions of organics with MPs by using DGT, aiding our understanding of MPs' adsorption/desorption behavior in the aquatic environment.
KW - Diffusive gradients in thin-films
KW - Waters
KW - Sorption
KW - Microplastics
KW - Organic pollutants
U2 - 10.1016/j.scitotenv.2023.163601
DO - 10.1016/j.scitotenv.2023.163601
M3 - Journal article
C2 - 37087021
VL - 882
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
M1 - 163601
ER -