Microplastics may be ubiquitous across ecosystems, yet the current state of exposure to microplastics in daily life remains poorly understood. We focused on drinking water in plastic bottles purchased from a local market in South Korea. The composition, amount, and size of organic matter in solid residues obtained by freeze-drying drinking water in a plastic bottle were determined using analytical methods including dry ashing, centrifugation, Raman analysis, and electron microscopy. A significant amount of organic matter was found in the plastic bottles (0.25-2.0 mg/L), and once the organic matter was concentrated and dried as a solid, it was not soluble in water. In addition, a series of stress to the plastic bottle, such as light, heat, and mechanical stress, did not significantly increase the organic matter within a month. The potential adverse effects of organic matter on humans were evaluated using the human intestinal Caco-2 cell line. The results showed no significant toxicity in cell viability even at relatively high concentrations of organic matter (1.0 mg/mL). However, the monitoring of the accumulation of organic matter in the human body over a longer period of time will be needed because of the higher probability of nanoscale material uptake in the long term.
Bibliographical noteFunding Information:
The authors acknowledge the support from the KU-KIST Research Fund, Korea University and National Research Foundation of Korea (2017M3D1A1039421).
© 2022 American Chemical Society.
- bottled drinking water
- organic matter
- residual solid
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Chemistry (miscellaneous)
- Environmental Chemistry
- Water Science and Technology