Table 1.

Abundance of microplastics in human organ systems

System	Organ	Sample Size	Abundance of microplastics	Size of Microplastics	Shape of Microplastics	Colour of microplastics	Polymer of Microplastics	References
Cardiovascular system	Blood vessels	22	1.6 ug/mL	>700 nm	NA	NA	PET, PE, PS, EPS, ABS, PMMA	[17]
	Thrombi	26	87 particles	2.1–26.0 μm	Block shaped	Yellow, green, red	LDPE, Pigment, Chromium Oxide, Phthalocyanine	[18]
	Vein	5	20 particles or 14.99 ± 17.18 microplastic/g of tissue	16–1074 μm	Fragment, fibre	NA	Alkyd Resin, Poly(vinyl propionate), Nylon-ethylene-vinyl acetate, nylon-EVA, tie layer	[19]
	Heart	15	NA	20–500 μm	NA	NA	PET, PVC, PMMA	[20]
Digestive system	Colorectal cancer tissue	11	331 Microplastics per individual or 28.1–15.4 particles/g tissue	0.8–1.6 mm	Fibre	Transparent, black, red, green, blue, brown, purple, and yellow	PC, PA, PP	[21]
	Liver	11	0–13 particles per sample or 3.2 particles/g tissue	4–30 μm	Fragment, microbead	NA	PS, PVC, PET, PMMA, POM, PP	[22]
Endocrine system	Placenta	NA	12 particles	>5 μm	Fragment	Blue, purple, pink, orange, red	PP	[23]
	Placenta		NA	>50 μm	NA		PE, PP, PU	[24]
	Placenta	17	149 microplastics particles	20.34–307.24 μm	Fragment, fibre, film, subspherical particle	NA	PVC, PP, PBS, PET, PC, PS, PA, PE, PSF	[25]
	Placenta	18	NA	20–500 μm	NA	NA	PU, PA, PE, PET, PC	[26]
Integumentary system	Face skin	2000	4265 microplastics particles	100–500 μm	Spheres fragment, film, fibre	Blue, red, yellow, transparent, black	PE, PET, PS, PVC	[27]
	Hand skin	2000	4051 microplastics particles	100–500 μm	Sphere, fragment, film, fibre	Blue, red, yellow, transparent, black	PE, PET, PS, PVC	[27]
	Hair	2000	7462 microplastics particles	100–500 μm	Sphere, fragment, film, fibre	Blue, red, yellow, transparent, black	PE, PET, PS, PVC	[27]
	Saliva	2000	645 microplastics particles	100–500 μm	Sphere, fragment, film, fibre	Blue, red, yellow, transparent, black	PE, PET, PS, PVC	[27]
Lymphatic system	Spleen	3	4 particles per sample or 1.1 particles/g tissue	5–25 μm	Fragment, Microbead	NA	PS, PVC, PET, PMMA, POM, PP	[22]
Respiratory system	Lung tissues	20	31 particles	1.6–16.8 μm	Fragment, fibre	Transparent, white, blue, grey, yellow, brown, orange	PP, PE, Cotton, PVC, CA, PA, PS, PU	[28]
	Lung granule nodules	100	65 particles	>20 μm	Fibre	Purple, blue, transparent, yellow, red	Cotton, PA, Polyester, Denim, Phenoxy resin,	[29]
	Lung tissue	13	39 particles	12–2475 μm	Fibre, fragment, film	NA	PP, PET, Resin, PE, PTFE, PS, PAN, PES, PMMA, PUR, SEBS, TPE	[30]
Reproductive system	Testis	6	31 particles in 4 of 6 testis samples	20–100 μm	Fragment, fibre, film, subspherical	NA	PS, PVC, PE, PP	[31]
Urinary system	Kidney	3	0 particle per sample	10–20 μm	NA	NA	NA	[22]

ABS – Acrylonitrile Butadiene Styrene, CA – Cellulose Acetate, CPE – Chlorinated Polyethylene, EPS – Expanded Polystyrene, EVA – Ethylene-Vinyl Acetate, HDPE – High-Density Polyethylene, LDPE – Low Density Polyethylene, NA – not available, NC – Nitrocellulose, mm – millimetre, PA – Polyamide, PAN – Polyacrylonitrile, PBS – Phosphate-buffered Saline, PBT – Persistent Bioaccumulative Toxic, PES – Polyethersulfone, PET – Polyethylene Terephthalate, PEMA – Phenylethylmalonamide, PC – Polycarbonate, PLA – Polylactic acid, PMMA – Polymethyl methacrylate, POM – Polyoxymethylene, PP – Polypropylene, PS – Polystyrene, PSF/PSU – Polysulfone, PU/PUR – Polyurethane, PTFE – Polytetrafluoroethylene, PVC – Polyvinyl Chloride, PVOH – Polyvinyl Alcohol, TPE – Thermoplastic Elastomere, SEBS – Styrene-Ethylene-Butylene-Styrene, μm – micrometre, μg/mL – microgram per millilitre