Fate and behavior of microplastics in biosolids: pollution characteristics and environm ental risks

点击翻译按钮获取中文摘要

Vermireactors were used for treating three different concentrations (0.5%, 1% and 2%) of LDPE and PBSA of <2 mm size with the addition of cow dung (CD). The CD supported the growth and hatchlings of earthworms, and the toxicity effect of both LDPE and PBSA microplastics on earthworm Eisenia fetida was analysed. For vermicomposting, the mixtures were kept for thermo stabilization for at least a week. After that, clitellated Eisenia fetida species of earthworms were incubated separately @ 5 worms’ 250 g-1 of the CD for a period of 120 days. Experimental samples of both CD and earthworms were collected at 60 and 120 days of vermicomposting and analyzed for various physico-chemical parameters, like the moisture content measured by drying the samples to a constant weight at 105 °C (24 h) in an oven. The organic matter content was determined by combusting the dried samples in a muffle furnace at 600 °C for 2 h. The pH and electrical conductivity (EC) were also determined by using the aqueous solution of dry sample with deionized water (w/v = 1/10) after shaken for 2 h. Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR) analysis were also conducted following standard protocols. The initial results suggested that the LDPE microplastics pose more threat to earthworm Eisenia fetida as compared to the PBSA microplastics.