Microplastics and their possible sources: The example of Ofanto river in southeast Italy.
Campanale Claudia,Stock Friederike,Massarelli Carmine,Kochleus Christian,Bagnuolo Giuseppe,Reifferscheid Georg,Uricchio Vito Felice
Environmental pollution (Barking, Essex : 1987)
Monitoring studies have quantified microscopic plastic debris, so-called microplastics, in freshwater systems, including banks, surface waters and sediments. However, there is a lack of knowledge of freshwater and terrestrial environments. When microplastics are released in freshwater environments, they will be transported and will not remain stationary. Moreover, their transport from sink to source (land-based to river systems) may depend on several factors such as weather conditions and river hydrology. The present study aims to investigate the abundance and composition of microplastics in the most important river of Apulia Region (Southeast Italy) evaluating the main drivers and possible input sources of microplastic debris. The following work is the first study showing an Italian river context. For this research five sampling campaigns have been conducted west of the Ofanto river mouth. Microplastics were collected by three surface plankton nets fixed in the middle of the river in order to reduce the spatial and temporal variability. For each campaign, a total of six replicates were sampled during two time slots. Microplastic concentrations ranged from 0.9 ± 0.4 p/m to 13 ± 5 p/m showing comparable values to or greater than those ones reported in other studies. A statistically significant difference in the average microplastic concentrations in different campaigns of this study has been observed, suggesting thus a temporal variation in plastic abundances. These significant differences could be explained by the hydrology of the river that influences the particle concentration with its physical forces such as flow velocity, water level and seasonal variability. Microplastics were found at higher concentrations during wet periods indicating a land-based origin probably connected to waste produced by the surroundings agricultural areas. In fact, Spearman's correlation results show a strong positive statistically significant correlation between the concentration of microplastics and the water level (R = 0.8475, p < 0.0001).
Polyethylene microplastics affect the distribution of gut microbiota and inflammation development in mice.
Li Boqing,Ding Yunfei,Cheng Xue,Sheng Dandan,Xu Zheng,Rong Qianyu,Wu Yulong,Zhao Huilin,Ji Xiaofei,Zhang Ying
Environmental pollution caused by plastics has become a public health problem. However, the effect of microplastics on gut microbiota, inflammation development and their underlying mechanisms are not well characterized. In the present study, we assessed the effect of exposure to different amounts of polyethylene microplastics (6, 60, and 600 μg/day for 5 consecutive weeks) in a C57BL/6 mice model. Treatment with a high concentration of microplastics increased the numbers of gut microbial species, bacterial abundance, and flora diversity. Feeding groups showed a significant increase in Staphylococcus abundance alongside a significant decrease in Parabacteroides abundance, as compared to the blank (untreated) group. In addition, serum levels of interleukin-1α in all feeding groups were significantly greater than that in the blank group. Of note, treatment with microplastics decreased the percentage of Th17 and Treg cells among CD4 cells, while no significant difference was observed between the blank and treatment groups with respect to the Th17/Treg cell ratio. The intestine (colon and duodenum) of mice fed high-concentration microplastics showed obvious inflammation and higher TLR4, AP-1, and IRF5 expression. Thus, polyethylene microplastics can induce intestinal dysbacteriosis and inflammation, which provides a theoretical basis for the prevention and treatment of microplastics-related diseases.