Ingesting chitosan can promote excretion of microplastics.

Recently, the presence of microplastics (MPs) in common foods such as salt and beverages has been widely reported Microplastics (MPs) have been widely reported in common foods, including salt and beverages. MPs spread through the food chain and are eventually ingested into the human body through the diet. They have been found to accumulate in human feces, blood, and liver tissues, raising concerns about the effects of continuous intake of foods containing MP on the body. We examined whether rats could rapidly excrete polyethylene MPs (average particle size of 200 μm) when the MPs and were mixed with non-digestive dietary materials in their feed (indigestible dextrin, lactosucrose, chitosan, and eggshell membrane proteins). The group that ingested chitosan showed significant changes, including increased fecal weight, increased MP excretion rate, and decreased intestinal MP retention rate. The MP excretion rates in feces 0-144 h after ingestion were 83.7% ± 3.8% in the control group and 115.6% ± 4.5% in the chitosan group. These findings indicate that chitosan effectively promotes the expulsion of polyethylene MPs. The addition of chitosan to food may reduce the potential harm caused by MPa to a variety of organisms, including humans.