Hideshi Seki

Plastic products have been extensively utilized in everyday life since their inception owing to their unique properties (Gu et al., 2020). The global production of plastic products increased to 390.7 million tons in 2021 and will exceed 500 million tons by 2025 (OECD, 2022). In general, plastic fragments or particles of less than 5 mm in diameter are known as microplastics (MPs) (Meng et al., 2020).

2. Materials and Methods 2.1. Materials Lactose one hydrate, phenol, potassium sodium tartrate, copper sulfate tetrahydrate, Folin-Lowry (phenol) reagent, L(+)-ascorbic acid, and ammonium molybdate were purchased from Kanto Chemical Ltd. (Tokyo, Japan). Boric acid, sulfuric acid, sodium hydroxide, sodium carbonate, hydrochloric acid, sodium sulfate, sodium chloride, sodium nitrate, carminic acid, and L-glutamic acid were purchased from Wako Pure Chemical Ltd. (Tokyo, Japan).

This is an early access version, the complete PDF, HTML, and XML versions will be available soon. Open AccessArticle by Hideo Maruyama 1,*, Akito Furukawa 2 and Hideshi Seki 1 1 Division of Marine Biosciences, Graduate School of Fisheries Sciences, Hokkaido University, Minato 3-1-1, Hakodate 041-8611, Japan 2 Mitsubishi Chemical Corporation, 1-1 Marunouchi 1, Tokyo 100-8251, Japan * Author to whom correspondence should be addressed.