A Production and Fractionation Protocol for Polyvinyl Chloride Microplastics

Abstract

Concerns about the presence of microplastics in the environment has increased in recent years, prompting more attention from scientists. Thorough exposure studies using artificially produced microplastics containing additives are required to assess their potentially hazardous effects. Therefore, an efficient microplastic production and fractionation protocol was established using a cryogenic grinding and wet-sieving approach. The developed cryogenic grinding method was able to produce (20–40 g/h) polyvinyl chloride (PVC) microplastics having a volume-weighted mean particle size of 391 µm and a span of 2.12. Performing a second grinding cycle on the same particles resulted in microplastics which were smaller (volume-weighted mean size = 219 μm) and had a narrower particle size distribution (span = 1.59). In addition, the microplastics were also fractionated into different particle size ranges using a vibrating wet-sieving tower. The latter technique allowed separating 10 g of PVC microplastics into seven different fractions using six sieves (Ø 200 mm) for 30 min while shaking. By using the developed method, PVC microplastics could easily be made and fractionated into desired particle-size ranges. The proposed protocol could also be adjusted to produce and fractionate microplastics of other plastics.

Ingestion and excretion dynamics of microplastics by black soldier fly larvae and correlation with mouth opening size

“…Microplastics were characterised by their shape, median particle size, and particle size distribution using a fluorescence microscope (Leica Microsystems, DMLS, Germany and Zeiss, Axioplan, Germany), an FEI Nova NanoSem 450 FEG scanning electron microscope (The Netherlands), and a Malvern Mastersizer 3000 (UK), according to Lievens et al (2022 and 2023) 13,28 . Briefly, for the fluorescent microscopical imaging, the microplastics were placed on a microscopical object slide covered by a coverslip.…”

“…The SEM images were then produced at 20 kV acceleration voltage with an ETD (Everhart-Thornley) detector, while all other parameters like magnification, working distance (WD) and horizontal field width (HFW) were displayed on the respective image. Lastly, the microplastics were suspended in continuously stirred water (3100 rpm) until an obscuration of approximately 5% was reached, prior to measuring the particle size distribution in triplicate 13,28 .…”

Bioaccumulation and biotransformation of plasticisers diisononyl phthalate and di(2-ethylhexyl) terephthalate in black soldier fly larvae reared on (micro)plastic-contaminated food waste

“…BSF larvae were obtained from the rearing colony of Centre of Expertise: Sustainable Biomass and Chemistry (Thomas More University of Applied Sciences, Belgium), hatched, and reared for the first eight days, according to Broeckx et al [35] . Eight days after hatching, approximately 15,000 larvae were transferred to their rearing container (HDPE polymer, not containing the compounds of interest, L = 60 cm, W = 40 cm, H = 20 cm, Engels Logistics NV) containing 10 kg artificial food waste substrate prepared according to Lievens et al [16] .…”

Approaches for Sampling and Sample Preparation for Microplastic Analysis in Laundry Effluents

“…Today, various CRMs and RMs are being developed that differ in appearance and chemical structure. For example, there are currently RMs in the form of spheres or foils [164,165], but at the time of writing, none have been found in fibrillar form that would be most suitable for assessing water pollution from textile industry effluents or laundry effluents.…”