TABLE 9.

In vivo genotoxicity of inorganic arsenic.

Reference	Test system	Animals	Concentration/treatment time	Results	Comments/additional information
Inorganic arsenic species other than arsenic trioxide
Osmond et al. (2010)	Quantitative PCR transcript amplification Lung	Mice (1, 8, 24 weeks old) (three to five animals/group)	Sodium arsenite 2 or 50 mg/kg bw/day in drinking water (24 h or 2 weeks), oral route	Adult animals (24‐week‐old): decrease of all BER gene transcript levels (APE1, LIG1, LIG3, OGG1, PARP1 and POLΒ) in lung tissue upon 2 weeks treatment Neonates whose mothers were exposed to 50 mg/kg. for 24 h or 2 weeks: increased levels of the APE1, LIG1, OGG1 and PARP1 transcripts in lung tissue	Number of animals not specified
Mehta & Hundal (2014)	Chromosomal aberrations Bone marrow	Mature female rats (n = 48; 12 animals/group)	Sodium arsenite 10, 30, 50 mg/kg (30 and 60 days), oral route	Positive: significant increase of CA in bone marrow cells after 30 days of exposure to 30 and 50 mg/kg; after 60 days exposure to all three doses (10, 30 and 50 mg/kg), dose‐dependent increase	Significant loss of bw Lack of data on cytotoxicity (mitotic index is not reported) Poor experimental details and data quality (unknown number of metaphases scored)
Takumi et al. (2014)	gpt mutation assay Liver Electrochemical detection (EC)‐HPLC, measurement of 8‐oxodG	Male gpt delta mice (5 weeks old), n = 12; 6 animals/group	Sodium arsenite 85 mg/kg (85 mg/L) in drinking water ad libitum (3 weeks); estimated: 4.3 mg/kg per day per mouse	Positive: increased gpt mutation frequency in the liver by 1.5‐fold. Mutational spectra: predominance of G:C to T:A transversion and higher frequency of deletion mutations Significantly higher levels of 8‐oxodG in the livers of arsenite‐exposed group	No changes in the average body weight, average relative liver weight significantly lower than in the control group
Fujioka et al. (2016)	gpt and Spi − mutation assay. Urinary epithelium liver	Old male gpt delta F344 rats, n = 36, 12 animals/group)	Sodium arsenite 87 mg/L; DMA(V) 92 mg/L in drinking water (13 weeks)	Negative: no effects on the mutant frequencies or mutation spectrum in urinary bladder epithelium or liver for both arsenicals	In the arsenite treatment group: the final body weights and absolute liver weights were significantly decreased; water intake and food consumption were significantly decreased from week 2. In the DMA(V) group: no effects on body and liver weights; increased water intake, no effects on food consumption A:T to T:A transversions in the gpt gene, being spontaneous mutations, excluded from mutation frequency and spectra.
Dash et al. (2018)	Alkaline comet assay in uterine cells	Female virgin albino Wistar strain rats (n = 24; six animals/group)	Sodium arsenite 10 mg/kg bw/day (2 or 8 days) without and with N‐acetyl‐l‐cysteine (NAC), oral route	Positive: Arsenite: significant increase of DNA breaks (number of comets, tail length); decreased DNA damage by co‐treatment with NAC	No changes in bw Significant weight loss for ovaries and uterus; ovarian and uterine tissue damage, disruption in steroidogenesis in the arsenic‐treated group
Nath Barbhuiya et al. (2020)	Alkaline comet assay in ovary and uterus	Swiss albino mice (6–8 week old; n = 30; six animals/group; five experimental points)	Sodium arsenite 2 mg/kg bw per day (30 days) Exposure also to smokeless tobacco alone and in combination with sodium arsenite, oral route	Positive: significant increase of DNA breaks (head/tail DNA, tail moment, tail length)	Significant loss of bw Data on target tissue toxicity: 50% decrease of relative organ weight and extensive histological abnormalities for both ovary and uterus
Arsenic trioxide
Kesari et al. (2012)	CA in bone marrow cells	Swiss albino mice (6–8 week old, n = 30, six animals/group)	Daily oral gavaging of aqueous solution of arsenic trioxide: arsenic content 3.0 mg/L, 1.5 mg/L, 150 μg/L and 30 μg/L (15 consecutive days) Doses tested: 0.0 0.3, 1.5, 15, 30 μg/kg bw per day	Positive: significant increase of structural chromosomal abnormalities upon exposure to the full range of doses tested; dose‐dependent increase Numerical abnormalities were induced by doses higher than 0.3 μg/kg bw per day	Lack of data on cytotoxicity (mitotic index is not reported) Too few metaphases scored per animal (50 instead of 200)
Khan et al. (2013)	MN assay in erythrocytes from bone marrow cells	Swiss albino mice (6–8‐week‐old, four groups, number of animals/group is not specified)	Daily oral gavaging of aqueous solution of arsenic trioxide: arsenic content 1.5 mg/L, 150 μg/L and 30 μg/L (15 consecutive days) Doses tested: 0.0–0.3‐1.5–15 μg/kg bw per day	Positive: significant increase in micronucleated cells al all doses tested, dose‐dependent	1000 erythrocytes scored (OECD protocol 2000) About six‐fold increase in micronucleated cells at the human reference dose of arsenic (0.3 μg/kg per day)
Nava‐Rivera et al. (2021)	Alkaline comet assay	Rats about 3 weeks old; males (n = 12) and females (n = 12)	Arsenic trioxide in drinking water 1 mg/L of arsenic equivalent to 1 mg/kg bw, for an interrupted period of 16 weeks	Positive: significant intra‐generational increase in the level of DNA breaks (% DNA in tail) in the arsenic lineage compared to the control lineage in all generations in both females and males. The inter‐genotoxic effect following the arsenic lineage, was in decrement across generations but with statistical significance in the F3 generation compared to the control group	The F0 parental was directly exposed to As; the F1 offspring experienced indirect exposure in utero and trough being breastfed until weaning in 21st day, F2 had a multigenerational indirect exposure as F1 germinal line, F3 transgenerational lineage neither direct nor indirect exposure to arsenic

Abbreviations: 8‐oxodG, 8‐hydroxydeoxyguanosine; A, adenine; APE1, apurinic/apyrimidinic endonuclease 1; BER, base excision repair; bw, body weight; C, cytosine; CA, chromosomal aberration; DMA(V), dimethylarsinic acid; DNA, deoxyribonucleic acid; EC‐HPLC, high‐performance liquid chromatography with electrochemical detection; F0, F1, F2, F3, filial generation 0, 1, 2, 3; G, guanine; LIG1, DNA ligase 1; LIG3, DNA ligase 3; MN, micronucleus; n, number; NAC, N‐acetyl‐l‐cysteine; NAC, N‐acetyl‐l‐cysteine; OECD, Organisation for Economic Co‐operation and Development; OGG1, 8‐oxoguanine DNA glycosylase 1; PARP1, poly (adenosine diphosphate‐ribose) polymerase 1; PCR, polymerase chain reaction; POLB, DNA polymerase beta; T, thymine.