Measurement and daily consumption of microplastics in drinking water from a Small Island Developing State-Fiji: from freshwater to groundwater sources

Abstract

The occurrence of microplastics (MPs) in drinking water has emerged as a significant source of this contaminant, posing an increased risk to human health. These MPs are now of extreme concern, especially on the possible harmful effects it may have on human health. This study is the first baseline MPs data in drinking water from Fiji. Raw, treated, tap, rain, ground, and bottled water were investigated for the presence of MPs and the ingestion rate by the different age groups. The analytical procedure was validated by determining recovery rates and analyses of blanks. The detection limit of the MPs was 10 µm, while fibers and particles ≥ 100 µm were analyzed on 100% of the filter area. The abundance of MPs in drinking water was source-dependent. Percentage removal of MPs from water treatment plants was 45-67%, resulting in the presence of 0.10 ± 0.03 to 2.90 ± 0.57 MPs L^-1 in tap water. The presence of MPs in bottled, rain, and groundwater was in the range of 0 to 2.20 ± 0.41 MPs L^-1. Fiber MPs predominated in all water sources except for bottled water. Main types of polymer identified were polyethylene, polypropylene, and poly(ethylene terephthalate). Estimated daily intake of MPs in tap water by children and adults were 0.0031-0.1813 and 0.0021-0.0829 MPs/kg bw/day, respectively. Information from this work in combination with information from the health sector will help to fully understand microplastic impact on human health and the actions that are required to mitigate it.

Keywords: Bottled water; Drinking water; Microplastics; Polymers; Water treatment plants.