Table 2.
Summary of Studies Evaluating Styrene Oxide in the Ames Test
| Assay version | Strains | Chemical purity | Range of test concentrations | Range of responses: lowest to highest tested concentration (revertants per plate) | Positive or negative | Reference |
|---|---|---|---|---|---|---|
| Plate incorporation | TA1537, TA1538 | “purest commercially available” | 1–200 μg/plate | No increase over background | Negative | Glatt et al. (1975) |
| Spot test | TA98, TA100, TA1535, TA1537, TA1538 | Not stated | 5 μL of liquid | TA1535: 535 (background = 135) TA100: 2,694 (background = 331) |
Positive | Milvy and Garro (1976) |
| Spotted on agar overlay or petri dish lid | TA100 | Not stated | 50–500 μg/plate | Agar overlay: 379–1,294 Petri dish lid: 294–3,092 |
Positive | Milvy and Garro (1976) |
| Plate incorporation | TA98, TA100, TA1535, TA1537, TA1538 | Not stated | 10−9–10−5 mol/plate | TA1535: 19–357 (without S9) and 18–484 (with S9) TA100: 115–1,111 (without S9) and 108–1,165 (with S9) |
Positive | Vainio et al. (1976) |
| Plate incorporation | TA98, TA100, TA1535, TA1537, TA1538 | 97% purity | 1 nmol/plate to 100 μmol/plate | TA100 and TA1535 (graphical data) | Positive | de Meester et al. (1977) |
| Plate incorporation | TA98, TA100, TA1535, TA1537, TA1538 | Not stated | 50–1,000 μg/plate | TA1535 (graphical data). Clear dose response but not clear that the response reaches two‐fold | Unclear result | Stoltz and Whitey (1977) |
| Suspension (including assessment of toxicity) | TA100 | Not stated | 0.42–2.02 μmol/plate | 268–467 revertants per 109 survivors | Positive | Sugiura et al. (1978) |
| Preincubation | TA98, TA100, TA1535, TA1537, TA1538 | Purified by distillation | 10–500 μg/plate | TA100: 84–268 (without S9) TA1535: 34–195 (without S9) |
Positive | Watabe et al. (1978) |
| Plate incorporation | TA98, TA100, TA1535, TA1537, TA1538 | Not stated | 1–10 μmol/plate | TA100 and TA1535 (graphical data) |
Positive | Busk (1979) |
| Suspension | TA100 | Purified by distillation | 1–6 mM | Graphical data: clear dose response. Response decreased by the addition of S9 | Positive | Yoshikawa et al. (1980) |
| Plate incorporation | TA98, TA100, TA1535, TA1537 | Not stated | 125–1000 μg/plate (4) Without S9 |
TA1535: 46–183 TA100: 246–1,334 TA1537: 6–8 TA98: 31–38 |
Positive (TA1535, TA100) Negative (TA1537, TA98) | El‐Tantawy and Hammock (1980) |
| Suspension | TA100 | Not stated | 0–33 mM/plate (graphical data) | Graphical data, clear dose response (approx. 1,200 at 33 mM) | Positive | Turchi et al. (1981) |
| Plate incorporation (exposure in desiccator) | G46, TA98, TA100, TA1530, TA1535, TA1537, TA1538 | Not stated | 16% and 24% (v/v) styrene oxide in air | TA100, TA1530, TA1535 (graphical data—see discussion) | Positive | de Meester et al. (1981) |
| Plate incorporation | TA98, TA100, TA1535, TA1537, TA1538 | Not stated | 0.1–10 μmol/plate | TA100: 47–488 | Positive | Watabe et al. (1980) |
| Preincubation | TA100 | Not stated (testing included “R” and “S” enantiomers) | 1–5 μmol/tube (higher concentrations gave survival <20%) | Racemic mixture: 387–1,374 | Positive | Pagano et al. (1982) |
| Preincubation | TA100 and TA100 GSH− derivatives | Not stated | 1–5 mM | Graphical data—clear dose response | Positive | Kerklaan et al. (1985) |
| Plate incorporation | TA100 | Not stated | 300 and 600 μg/plate Without S9 (Used as positive control: nine separate experiments) |
0 μg/plate: 91–187 300 μg/plate: 275–435 600 μg/plate: 400–723 |
Positive | Cheh (1986) |
| Preincubation | TA100 | Purified by distillation | 0.01–10 μmol/tube | 108–1,406 | Positive | Rosman et al. (1986) |
| Plate incorporation Preincubation and Tedlar™ Bag | TA100, TA102 | “highest commercially available” | 50–1,000 μg/plate | Plate: TA100: 120–242; TA102: 247–309 Preincubation: TA100: 154–343; TA102: 268–410 Tedlar™ Bag: TA100: 132–122; TA102: 258–276 |
TA100: Positive (the preincubation method was the most sensitive) TA102: Negative |
Hughes et al. (1987) |
| Preincubation | TA100 | >98% purity (testing included “R” and “S” enantiomers) | 50–800 μg/plate | Graphical data. Clear dose response. The “R” enantiomer is more potent | Positive | Seiler (1990) |
| Plate incorporation | TA100 | “Pure” | 150–1,500 μg/plate (10) Without S9 (seven repeat experiments/two labs) |
186–1,450 | Positive | Claxton et al. (1991) |
| Preincubation | TA98, TA100 | 98% purity | 33–666 μg/plate without S9 33–3,333 μg/plate with S9 |
TA98: 16–34 TA100: 182–628 (without S9—response lower with S9) |
Positive: TA100 Negative: TA98 |
Zeiger et al. (1992) |
| Plate incorporation | TA100, TA104 | Not stated | 0.5–8 μM 0.5–32 μM Without S9 (two separate experiments) |
TA100: 144–2,532 TA104: 421–1,501 |
Positive | Einisto et al. (1993) |
| Plate incorporation | TA100 | Purified by chromatography (testing included “R” and “S” enantiomers) | 1–8 μmol/plate | “R”: 216–1,146 “S”: 180–717 |
Positive | Sinsheimer et al. (1993) |