Developing methods to quantify two luminescent polymer nanoparticles inside freshwater clam and fish models

The accumulation of polymer nanoparticles (PNPs) in the aquatic environment threatens the health of animals and, eventually, our food chain. However, there remains a lack of effective quantitative methods to assess the bioaccumulation and translocation of PNPs in animal tissues. Here, a new and easy method for the extraction and quantification of luminescent primary polymer nanoparticles (PNPs) such as polyvinyl chloride (PVC NPs), and polymethyl methacrylate (PMMA NPs) from animal tissues is developed and discussed in detail. The method was validated by using 2 animal models (Asian clam Corbicula fluminea and Tiger barb fish Puntigrus tetrazona) with experimental conditions involving 2 exposure concentrations (1 and 5 ppm) ⅹ 4 exposure times (4, 8, 12, and 24 h), and comparing the results using the fluorescent imaging method. Our results showed that recovery rates of the two PNPs from the tissues of Tiger barb fish and Asian clams were up to 81.8 % and 83.6 %, respectively. The two PNPs were accumulated in the gills (0.053 μg/mg and 0.148 μg/mg), mantle (0.036 μg/mg and 0.105 μg/mg), and gas bladder (0.020 μg/mg and 0.098 μg/mg) of Asian clams and Tiger barb fish based on the chemical nature, concentrations and exposure times. A weak linear relationship was observed between the fluorescent intensities and the amount of PNPs extracted from the animal tissues. Since PNPs are detected and identified in different human and animal tissues, the results published in this paper are timely and important for understanding the impact of PNPs on the overall health of the ecosystem.