Mutant frequencies (mean ± SE ×10−5) in different cell types and liver tissue from mice treated with B[a]P at 7 days of age.

Pfu, plaque-forming unit; MF, mutant frequency; Pachy, pachytene spermatocytes; RS, round spermatids; SP, epididymal spermatozoa.*Significantly (P†Significantly (P‡Significantly (P§Significantly (P¶Significantly (P||Significantly (PPfu（plaque-forming unit，噬斑形成单位）；MF（mutant frequency，突变频率）；Pachy（pachytene spermatocytes，粗线期精母细胞）；RS（round spermatids，圆形精子细胞）；SP（epididymal spermatozoa，附睾精子）。* 显著（P）；† 显著（P）；‡ 显著（P）；§ 显著（P）；¶ 显著（P）；|| 显著（P）