Microplastic Contamination of Surface Water-Sourced Tap Water in Hong Kong-A Preliminary Study

Abstract

Microplastics have been documented in a wide range of commercially available food products, and the presence of microplastics in tap water has received considerable attention in recent years. Although microplastics in drinking water pose a low concern for human health at current levels of exposure, there is a need to understand the potential pathways for human microplastic exposure. With the application of Rose Bengal staining, microplastics in 110 surface water-sourced tap water samples from urban sources in Hong Kong were qualified and morphologically characterized. A total of 224 items were identified in 86 (78.2%) samples with a mean concentration of 2.181 +/- 0.165 n L-1. Fibrous and smaller (<1 mm) microplastics predominated in samples, accounting for 97.8% and 65.1% of the total microplastic count, respectively. Our results indicated a comparatively low level of microplastic contamination of tap water in Hong Kong. The potential sources of microplastics could be microplastic-polluted water bodies, atmospheric input and mechanical abrasion of plastic equipment during water treatment and distribution.