Table 2 Revertants/ plate, standard deviation and mutagenicity index (in brackets) for the strains TA98, TA100, TA102 and TA97a of S . typhimurium after treatment with various doses of HK, with (+S9) and without (−S9) metabolic activation

HK

0.0 ^a

22 ± 2

32 ± 1

132 ± 6

123 ± 1

243 ± 4

391 ± 8

164 ± 4

163 ± 2

9.7

18 ± 4 (0.8)

32 ± 1 (1.0)

134 ± 4 (1.0)

130 ± 6 (1.1)

238 ± 8 (1.0)

376 ± 7 (1.0)

165 ± 5 (1.0)

172 ± 10 (1.0)

19.5

23 ± 3 (1.0)

34 ± 3 (1.1)

129 ± 6 (1.0)

128 ± 6 (1.0)

231 ± 8 (0.9)

363 ± 3 (0.9)

165 ± 9 (0.9)

187 ± 3 (1.1)

39.0

25 ± 3 (1.1)

33 ± 4 (1.0)

134 ± 5 (1.0)

115 ± 8 (0.9)

213 ± 4 (0.9)

354 ± 4 (0.9)

146 ± 5 (0.9)

166 ± 5 (1.0)

58.5

25 ± 2 (1.1)

28 ± 1 (0.8)

112 ± 3 (0.8)

134 ± 2 (1.1)

201 ± 6 (0.8)

398 ± 9 (1.0)

175 ± 4 (1.1)

172 ± 2 (1.0)

78.0

24 ± 5 (1.1)

31 ± 2 (1.0)

140 ± 9 (1.1)

120 ± 8 (1.0)

186 ± 2 (0.8)

402 ± 3 (1.0)

163 ± 8 (1.0)

146 ± 4 (0.9)

Ctrol +

1347 ± 88^b

1567 ± 115^e

1582 ± 98^c

1456 ± 78^e

1656 ± 60^d

1932 ± 97^f

1766 ± 49^b

1789 ± 89^e