Table 5 Common mutagens that increase SCE and protective factors that reduce SCEs measured with BrdU.

Nonsmokers 7.03 ± 0.33 (n = 9); smokers (9.46 ± 0.46) (n = 14)

Blood specimens from clinically healthy male subjects between 20 and 52 years of age (19)

Green tea and plant polyphenols

Cigarette smokers, 9.46 ± 0.46

Smoker SCEs (7.94 ± 0.31) were comparable to those of nonsmokers (7.03 ± 0.33)

Smoking cigarettes and drinking green tea significantly affected SCE frequency and explained 32.7% of SCE variation (P < 0.002) (19)

3.36 ± 0.24

Mouse bone marrow cells in vivo (68)

Green tea extract given to anesthetized animals

Dimethyl-nitrosamine 23.40 ± 0.94 at 18 h

12.12 ± 0.07 (a similar effect at 24 h; more modest effects at other times)

The suppression rate was significantly different from mice given only dimethyl nitrosamine (t test P < 0.05) (68)

4.1 ± 0.46 for not fasted (29% cells have 0–2 SCEs)

Male Wistar rats every other day fasting 12 wks (69)

Dietary limitations

Diet

1.8 ± 0.12 for fasted (72% cells have 0–2 SCEs)

Significant differences in the numbers of SCEs (t test P< 0.05) (69)

4 at 6 h to 6 at 48 h exposure to radiation

Human peripheral blood lymphocytes exposed to 1.8 Ghz radiation (70)

Ginkgo biloba

RF/microwave radiation 8 at 6 h to 13 at 48 h

6 at 6 h and about 7 at 48 h

There was a significant increase (P < 0.05) in SCE frequency in RF-exposed lymphocytes compared with sham controls (70)

0.24 ± 0.12/cell

Traffic policemen in Bangkok Thailand (71)

4.40 ± 0.93/cell with Benzene, toluene, CO, formaldehyde, etc.

A significantly higher SCE frequency in policemen was observed (P < 0.05) (71)

4.3 ± 0.19

Human lymphocytes (72)

6.64 ± 0.88 with hydroquinone, a product of benzene metabolism

Hydroquinone significantly increased micronuclei and SCE (P < 0.0001) (72)

4.6 ± 0.37 to 6.0 ± 0.39/cell

CHO-K1 cells (73)

Ascorbate, glutathione

8.6 ± 0.52 Phenyl hydroquinone, a metabolite of o-phenylphenol, an agricultural fungicide and surface disinfectant (Lysol)

5.1 ± 0.39 with ascorbate, 4.6 ± 0.37 with glutathione

Ascorbate and glutathione significantly decrease SCEs versus Phenyl hydroquinone alone (P < 0.05) (73)

12/cell

Ataxia telangiectasia patient cells (affects BRCA1/2-mediated pathways) (4)

18 after 2 Gy radiation

5.2 ± 1.53/cell

Human peripheral blood lymphocytes (74)

Broccoli head extract

MMC 72.7 ± 8.57

33.33 ± 1.71

Results with mutagen showed significant differences from untreated control and significant differences between mutagen and mutagen plus broccoli extract (P < 0.05) (74)

0.18 ± 0.01/cell

Chinese hamster fibroblasts (75)

Squalene

H₂O₂ 0.39 ± 0.01

0.24 ± 0.05

Pretreatment with squalene significantly decreased the frequency of SCE induced by H₂O₂ (P < 0.05)

0.244 ± 0.003/cell

Chinese hamster V79 cells (76)

α-Tocopherol

H₂O₂ 0.49 ± 0.01

0.252 ± 0.003

Increased SCEs and protection were statistically significant (P < 0.05)

All cells from niacin-deficient rats had ≥5 SCEs; 51.2% had 5–10; 48.8% had ≥11 SCEs

Rat bone marrow cells (77) IP BrdU injection in vivo 1 mg/g

Niacin

Etoposide 28.4% of niacin-deficient rats had 5–10 SCEs and 71.6% had ≥11

83% of control cells had 0–4 SCEs; 17% had 5–10 SCEs