Table 3.

The toxicological, pathological, and behavioral changes in mice and rats on MP/NP treatment. (We modified a summary table referred from [23].)

Classification	Size	Accumulated Tissue	Toxicological, Pathological, and Behavioral Changes	References
Detection of significant toxicological and pathological changes
PS	5 and 20 μm	Gut, liver, and kidney	Induction of inflammatory response and lipid accumulation in the liver Alteration in the lipid profile and impairment of energy metabolism (reduction in adenosine triphosphate (ATP) levels) Increase in liver oxidative stress markers and decrease in acetylcholinesterase activity	[19]
PS	0.5 and 50 μm	-	Decrease in body, liver, and lipid weights Decrease in mucus secretion in the gut Alteration in the gut microbiota Alteration in the hepatic lipid profile and expression of some genes related to lipid metabolism	[22]
PS and PE + OPFRs a	0.5–1.0 μm	Gut and liver	Enhancement in OPFR-induced oxidative stress, neurotoxicity, and metabolic disorder	[93]
PS	5 μm	Gut	Dysfunction of the intestinal barrier Dysbiosis of the gut microbiota Induction of bile acid metabolic disorder	[94]
PS	5 and 20 μm	Gut, liver, and kidney	Toxicokinetic/toxicodynamic modeling of organ-bioaccumulation and biomarker responses Alteration in the oxidative stress, energy, and lipid metabolism markers	[95]
PS	0.5 and 5 μm	-	Alteration in serum and liver metabolic markers Induction of fatty acid metabolic disorder in the F1 offspring after exposure to maternal MPs	[96]
PS	10–150 μm	-	Alteration in the composition and diversity of gut microbiota Increase in the IL-1α secretion in the serum and decrease in the Th17 and Treg cells, among CD4+ cells Induction of the inflammatory response in the small intestine after treatment with high-concentration MPs	[97]
PS	5 μm	-	Alteration in histopathology, and serum and hepatic markers for liver toxicity Alteration in the transcription of genes related to glycolipid metabolism Dysbiosis of the gut microbiota and dysfunction of the gut barrier Induction of intergenerational effects and long-term metabolic consequences in the F1 and F2 generations after exposure to maternal MPs	[98]
No detection of significant toxicological and pathological changes
PS	0.025 and 0.05 μm	-	No significant change in the neurobehavioral consequences	[23]
PS	1, 4 and 10 μm	-	No significant change in body/organ weight and histopathological structure No significant change in the inflammatory response and oxidative stress Intestinal tissue uptake of a low number of particles	[55]

^a OPFR—organophosphorus flame retardant.