[Study on gonadal developmental toxicity of dibutyl phthalate in male zebrafish of F1 generation].

OBJECTIVE

This study aims to explore the effects of dibutyl phthalate (DBP) on the gonad development of F1 generation male zebrafish.

METHODS

Fourty-eight pairs of adult zebrafish were randomly divided into 4 groups of 12 pairs each: blank control group, 0.01% acetone solvent control group, 1250 microg/L DBP high-dose group, and 625 microg/L DBP low-dose group. After 30 days of exposure, zebrafish in each group were mated and the F1 generations were raised up to 180 dph in clean water. Twenty F1 male zebrafish in each group underwent gonadal index (GSI) analysis and gonad histopathology examination.

RESULTS

GSI of F1 male zebrafish in high-dose group (5.23% +/- 1.5%) was significantly lower than that in blank control (6.09% +/- 2.5%) or solvent control (6.08% +/- 1.2%) (P < 0.05). Histological examination on testis showed that DBP inhibited male gonadal development of the F1 offspring and led to abnormal seminiferous tubules with clear characteristics of extensive and significant proliferation of Leydig cells accompanied by low sperm count.

CONCLUSION

Gonadal development can be inhibited to different degrees by prenatal exposure to DBP in F1 male zebrafish, including abnormal seminiferous tubules, reduced sperm count as well as Leydig cell hyperplasia. This anti-estrogen activity of DBP in zebrafish is similar to those DBP-induced testicular effects observed in male rats, marmoset and human beings.