Abstract
Plastic fragments < 5 mm, known as microplastics (MPs), are ubiquitously present in the marine environment. Research on MPs pollution has gradually shifted from field investigations to laboratory studies. With the rapid growth of plastic consumption and the prevalence of aquaculture products, studies on marine MPs have focused on key marine species, such as mollusks. This review summarizes the recent knowledge including 77 important relevant literatures (from 2010 to 2021) on MPs contamination in mollusks with the objectives of (1) elucidating the current status of MPs pollution levels in mollusks, (2) highlighting the main methods and techniques for separation, extraction, and identification of MPs in soft tissues of bivalves and (3) presenting the current research progress and future directions. The review visually presents some of the important results in graphic form, which shows that the most common polymer plastics in bivalves are polypropylene, polystyrene, and polyethylene, and the shapes were mainly fiber and threadiness, mollusks are more likely to feed smaller MPs, most of the MPs in bivalves are less than 500 μm, and the abundance of MPs in seawater and the abundance of MPs in mollusks have a positive relationship, etc. This review will provide a comprehensive reference for studies of microplastics in marine organisms and the ecological pollution, and also has scientific guiding significance in the research method.
Highlights
Microplastics (MPs) refer to miniature plastic particles having a size of less than 5 mm, which form after large plastic waste enters the aquatic environment and breaks down due to the influence of photodegradation, physical degradation, and biodegradation (Browne et al, 2008; Moore, 2008; Cole et al, 2011)
This review will provide a comprehensive reference for studies of microplastics in marine organisms and the ecological pollution, and has scientific guiding significance in the research method
It has been confirmed that when the mussels (M. edulis) contaminated with PS-MPs were fed to crabs (Carcinus maenas), the PS-MPs were found in the stomach, hepatopancreas, ovaries, gills, and hemolymph of crabs, with the highest content in the hemolymph (Farrell and Nelson, 2013)
Summary
Microplastics (MPs) refer to miniature plastic particles having a size of less than 5 mm, which form after large plastic waste enters the aquatic environment and breaks down due to the influence of photodegradation, physical degradation, and biodegradation (Browne et al, 2008; Moore, 2008; Cole et al, 2011). Mollusks are rich in nutrition, high economic value, and easy to breed They are a highly regarded aquaculture resource, especially bivalves, which are typical filter feeders, constantly filtering out microbes and organic matter from the surrounding water (Xu et al, 2017). As the characteristics of MPs will affect their utilization rate by mollusks, we collected and analyzed information about the compositions of ingested MPs (Supplementary Table 1 and Figure 1). According to their morphological characteristics, MPs are usually classified as fiber/line, fragments, films, pellets/balls, and foams. When the density of MPs is less than that of seawater, such as low-density PE (0.89–0.93 g cm−3), high-density PE (0.94–0.98 g cm−3), PP (0.83–0.92 g cm−3), plastic particles float on the sea surface,
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
