Table 2.

In vivo assessments of selected toxic substances.

Substance	Radioisotope and Labeling Method	Exposure Route	Animal Model	Results	Ref.
Perfluorooctanoic acid	14C, incorporation	Oral exposure	Angus cows	Biodistribution of 14C-labeled perfluorooctanoic acid in blood, urine, and feces over 28 days and in tissues at the time of slaughter (28 days) Measurement of plasma elimination half-life	[26]
Perfluorooctane sulfonate	35S, nucleophilic addition to [35S]SO2	Oral exposure	C57BL/6 mice	Biodistribution of low and high doses of 35S-labeled perfluorooctane sulfonate in organs over 5 d Whole-body autoradiogram of a mouse 48 h after oral administration	[28]
	35S, nucleophilic addition to [35S]SO2	Gestational exposure	Pregnant C57BL/6 mice	Biodistribution of 35S-labeled perfluorooctane sulfonate in the organs of dams, fetuses, and pups Whole-body autoradiograms of pregnant mice 48 h and 96 h after exposure	[29]
Perfluorinated alkyl compounds	18F, isotopic exchange (19F → 18F)	Intravenous injection	CD1 mice	Biodistribution of 18F-labeled perfluorocarbons in organs over 4 h Comparison of biological uptake values of three different perfluorocarbons (PFOA, PFHxA, PFBA)	[30]
Bisphenol A	14C, incorporation	Intravenous and topical injection, percutaneous absorption	SD rats (in vivo), human skin (in vitro)	Quantification of radioactivity in urine, feces, skin, and carcasses (14C-BPA mass balance) 1–72 h after administration In vivo and ex vivo measurement of percutaneous 14C-BPA absorption	[35]
	14C, incorporation	Intraperitoneal injection	Pregnant mice	Biodistribution of 14C-BPA in the organs of pregnant mice and newborn mice determined via autoradiography	[36]
	14C, incorporation	Percutaneous absorption	Human skin (in vitro)	Kinetic measurements of 14C-BPA penetration Distribution of 14C-BPA in the stratum corneum after incubation for 24 h	[37]
Manganese	52Mn	Nasal inhalation, intravenous injection	CD1 mice	Biodistribution of inhaled and injected 52Mn in organs over 24 h Whole-body PET/CT imaging of intravenously injected 52Mn over 72 h	[38]
Graphene	125I, electrophilic substitution	Intravenous injection	BALB/c mice	Biodistribution of 125I-labeled graphene in organs over 60 days Hepatic and renal toxicity over a three-month period after exposure	[39]
Graphene oxide	125I, electrophilic substitution	Intratracheal instillation	Kunming mice	Biodistribution of 125I-labeled graphene oxide in organs over 12 h Whole-body SPECT/CT imaging for 1 h Pulmonary toxicity over a three-month period after exposure	[40]
Graphene	14C, graphitization with 14C-labeled phenol	Intake	Daphnia magna	Quantification of 14C-labeled graphene uptake and excretion in different aqueous media	[41]
Graphene	14C, graphitization with 14C-labeled phenol	Intratracheal instillation, oral exposure	ICR mice	Biodistribution of 14C-labeled graphene in organs over 3 d (oral exposure) or 28 d (intratracheal instillation) Quantification of translocation from the lungs to other internal organs Pulmonary toxicity 24 h after exposure	[42]
Iridium NPs	192Ir, incorporation	Nasal inhalation	SD rats	Measurement of radioactive iridium NP (10, 15, 35, and 75 nm) retention half-life in the lungs Quantification of translocation from the lungs to other internal organs	[43]
PHMG	111In, DOTA chelation	Whole-body inhalation, intratracheal instillation	SD rats	Biodistribution of 111In-labeled PHMG aerosols in organs over 168 h Quantification of translocation from the lungs to other internal organs Whole-body SPECT/CT imaging over 24 h	[44]
DEP	125I, self-assembly with 125I-labeled pyrene	Intratracheal instillation, oral exposure	ICR mice	Biodistribution of 125I-labeled DEP particles over 48 h Whole-body SPECT/CT imaging over 48 h	[45]
LPS	111In, DOTA-BODIPY conjugate chelation	Intravenous injection	C57BL/6 mice	Biodistribution and SPECT/CT imaging of 111In-labeled LPS in organs over 24 h Ex vivo fluorescence imaging of liver tissues	[46]
E. Coli	99mTc, [99mTc(CO)3] chelation with intracellular proteins	Intravenous injection, oral exposure	ICR mice	Organ biodistribution of 99mTc-labeled E. Coli over 8 h Whole-body SPECT/CT imaging over 8 h	[47]
S. Aureus	99mTc, radiolabeled peptide attached to the cell membrane	Intramuscular injection	Swiss mice	Organ biodistribution of 99mTc-labeled S. Aureus over 28 h Whole-body SPECT and fluorescence imaging of infected muscle over 28 h	[48]
AAV	124I, electrophilic substitution/modified Bolton–Hunter reagent	Intraparenchymal injection	CD-1 mice	Whole-body PET/CT imaging of 124I-labeled AAV over 8 h days Measurement of brain uptake over 8 d	[49]
AAV	64Cu, NOTA chelation followed by conjugation on the AAV surface	Intravenous injection	C57BL/6 mice	Organ biodistribution of 64Cu-labeled AAV over 21 h Whole-body PET/CT imaging over 21 h Comparison of AAV9, AA9-TC, and PHP.eB viral capsid uptake by the brain	[50]