In order to assess risks to the natural environment from microplastics, it is necessary to have reliable information on all potential inputs and discharges. This relies on stringent quality control measures to ensure accurate reporting. Here we focus on wastewater treatment works (WwTWs) and the complex sample matrices these provide. Composite samples of both influent and effluent were collected over a 24 h period on two separate occasions from eight different WwTWs across the UK. Sludge samples were taken on five occasions from five WwTWs. The WwTW treatments included activated sludge, trickling filter and biological aerated flooded filter with or without tertiary treatment. Using micro-FTIR analysis, microplastics ≥25 μm were identified and quantified. Procedural blanks were used to derive limits of detection (LOD) and limits of quantification (LOQ). Where values were above the LOQ, microplastics in the influent ranged from 955 to 17,214 microplastic particles/L and in the effluent from 2 to 54 microplastic particles/L, giving an average removal rate of 99.8%. Microplastics could be quantified in sludge at concentrations of 301–10,380 microplastics/g dry weight, this analytical method therefore revealing higher concentrations than reported in previous studies. The most common polymers present overall were polyethylene (PE), polypropylene (PP) and polyethylene terephthalate (PET). We also report on critical considerations for blank corrections and quality control measures to ensure reliable microplastic analysis across different sample types.
The current study examines the contamination of microplastics in three greenhouse types: abandoned, normal, and simple. The findings revealed that the abundance of microplastics was found to be the highest in the abandoned greenhouse, followed by the normal greenhouse and simple greenhouse. The mean abundance of microplastic organic fertilizer and irrigation water was also high.[…]
The study examines the distribution of residual film after eight years of film mulching in mid-April 2018. Results from the study revealed that eight years of mulching significantly increased the quantity of agricultural mulch film residues in the soil. The size of residual film fragments was found to vary from 0.25 cm2 to 109 cm2,[…]
A study in Yuanmou County, Yunnan Province, investigated microplastic pollution in different land uses, including facility farmland, traditional farmland, orchard, grassland, and woodland. Results showed a significant difference in microplastic abundance and characteristics between different land use types. Facility farmlands, traditional farmlands, and orchard lands had higher microplastic abundance than grasslands and woodlands. The main[…]
The study analysed 225 soil samples from maize planting zones in northern China, revealing that long-term plastic film mulching increases microplastic pollution in agricultural soils. The abundance of microplastics was significantly higher in mulched soils (754 ± 477 items kg-1) than in non-mulched soils (376 ± 149 items kg-1). The length of time with film[…]
The study examined the relative abundances and morphological distributions of microplastics (MPs) in water, sediments, and farmland soils in the Caohai Lake region. The estuary in the study area was considered a potential sink for MP transportation. Transparent and black MPs accounted for a large proportion of MPs in the five environments, with possible sources[…]