Early screening of suspected microplastics in bottled water in the Santiago Metropolitan Region of Chile.

Bottled water has emerged as a possible healthier alternative due to concerns about the quality of drinking water sources. However, recent studies have detected worrying concentrations of environmental contaminants in bottled water, including microplastics. Therefore, it is an emerging need to quantify their concentrations in local suppliers which could differ among countries and regions. In this work, we used fluorescence microscopy with Nile Red for the identification and quantification of potential microplastics in twelve brands of bottled water distributed in the Santiago Metropolitan Region of Chile. The average concentration of microplastics was 391 ± 125 p L, while the highest concentration observed was 633 ± 33 p L. Microplastics between 5 and 20 μm were the major contributors, a size fraction that has been reported to be susceptible to accumulate in the digestive tract or generate potential alterations in the lymphatic and circulatory systems. The estimated daily intake value for per capita was estimated to be 229 p kg year for people weighing 65 kg and 198 p kg year for those weighing 75 kg.