We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Limited effects of different real groundwaters from three coastal cities in China on the transport of low-concentration nanoplastics in quartz sand
Summary
Researchers conducted column transport experiments with polystyrene and PLGA nanoplastics at low concentrations in real groundwaters from three Chinese coastal cities, finding that PS nanoplastics transported highly (average breakthrough plateau of 0.81) while PLGA transported poorly (0.19) due to shape- and size-induced straining, and that similar groundwater pH across sites produced comparable transport behaviours despite differing water chemistries.
Nanoplastics (NPs) have been widely detected in soil-groundwater systems. However, to date, the effect of real groundwater on the fate and transport of NPs has been poorly understood. In this study, the transport and retention behaviors of both polystyrene and poly(lactic-co-glycolic acid) NPs (PS NPs and PLGA NPs) in different real groundwaters from three coastal cities in China were explored using column experiments. PS (0.51 and 1.1 μm) and PLGA (1 μm) NPs with a low concentration of 2 mg L-1 were employed. Close observation showed that the transport of PS NPs was much higher than PLGA NPs in different groundwaters, with an average breakthrough curve plateau (C/Co) of ∼0.81 for PS NPs and ∼0.19 for PLGA NPs, respectively. As observed for PLGA, the plastic shape- and size-induced straining may be the reason for the minimal transport. Interestingly, we found that although the physicochemical characteristics of different real groundwaters varied significantly, the transport of certain NPs in real groundwater was similar with negligible differences. Closer inspection indicated that similar pHs of different groundwaters may be the reason contributing to these findings. Further investigation revealed that the transport behaviors of PS and PLGA NPs in real groundwater did not follow the classical DLVO theory. These findings suggest that the fate and transport of NPs in real soil-groundwater systems are much more comprehensive than the prediction based on DLVO theory and need intensive investigation.