Читать книгу Plastic and Microplastic in the Environment - Группа авторов - Страница 39

According to literature, MPs sources can be categorized as primary sources or secondary sources (Andrady 2011; Cole et al. 2011). We can refer to primary sources as those MP particles released into the environment which were manufactured in the range of micrometers, whereas secondary sources are those sources that produce the MPs by the process of disintegration and/or breakdown of larger plastic particles due to various physical and chemical mechanisms (e.g. exposure to sun rays, weathering, mechanical wear and tear, etc.). Faure et al. (2012) and Eriksen et al. (2013) propose three major sources: (i) effluent from wastewater treatment plants (WWTP); (ii) sewage treatment overflow during high‐volume rain events; and (iii) runoff from agricultural or public lands. In recent literature, sources of MPs in personal care and cosmetic products and clothing have been reported (Gouin et al. 2015). Sundt et al. (2014) tried to attempt a detailed study of source apportionment for Norway; primary as well as secondary sources that release MPs and in the study, and made the conclusion that the MPs from tire dust are the sources for the largest contribution in the Baltic Sea with a small contribution from other consumer products. Data for other terrestrial sources of MPs are almost nonexistent, for example, agricultural and urban soils (Lwanga et al. 2017). Literature suggests that potential sources of MPs from agricultural equipment or use of WWTP products in agriculture along with landfill waste disposal sites soil pose a threat to the environment, which have not been assessed in detail (Wagner et al. 2014). As per literature, polythene (PE) and polyethylene terephthalate (PET) are found to be the major polymer type found in freshwater samples (Figure 2.3, Li et al. 2020).

Figure 2.3 Composition of microplastics found in freshwater samples

Source: Modified from Li et al. 2020.