Adsorption of Heavy Metal with Aged Microplastic in Groundwater Under Varying Organic Matter Content

From 1950 to 2016, the world produced 460 million metric tonnes of plastic, up from only 1.5 million in 1950 (Hoornweg and Perinaz, What a Waste: A Global Review of Solid Waste Management, 2012; Law et al., Sci Adv 6:1–8, 2020). Approximately 50% of the produced total plastic is used in packagingPackaging for consumer goodsConsumer goods, which is single-use in natureNature (Hopewell et al., Philos Trans R Soc B Biol Sci 364:2115–2126, 2009). As a result, a great amount of plastic trash is ending up in the natural environmentNatural environment, which can cause significantSignificant risks to human healthHuman health (Kehinde et al., Heliyon 6, 2020). Larger plastic debrisPlastic debris degrades into smaller particles after a certain weatheringWeathering action, UV light-induced degradation, temperatureTemperature and salinitySalinity changes, and mechanical and biological weatheringBiological weathering (Zettler et al., Environ Sci Technol 47:7137–7146, 2013). Once reduced to a size less than 5 mm, these plastic debrisPlastic debris are referred to as microplasticsMicroplastic (MP) (Thompson et al., Science 304:838, 2004). MP has been gaining attention due to its omnipresence in the environment. The occurrence of MP has been reported in soil, wastewaterWastewater, seawaterSeawater, freshwaterFreshwater, plant biomassPlant biomass, human bloodHuman blood, and even in the atmosphere (Browne et al., Environ Sci Technol 45:9175–9179, 2011; Barnes et al., Philos Trans R Soc B Biol Sci 364:1985–1998, 2009; Eriksen et al., Mar Pollut Bull 77:177–182, 2013; Liu et al., Environ Sci Technol 53:10, 612–10, 619, 2019; Rillig, Environ Sci Technol 46:6453–6454, 2012; Zhang et al., Earth-Sci Rev 203, 2020).