ABSTRACT
Objective To analysis the effects on the growth of rats by repeated restraint in dermal exposure test. Methods SD rats in the restraint group was bound for 6 hours per day for 91 days according the way by dermal exposure, while SD rats in the control group didn't receive the treatment. Clinical signs, body weight and food consumption changes were observed for 91 days. When the study was terminated, hematology, clinical biochemistry, urinalyses, gross necropsy, and histopathology were carried out. Statistical methods such as the generalized estimating equation were used to compare the differences between two groups. Results The statistical results of generalized estimating equation showed that there was an interaction between the group and test time for male and female rats in body weight changes (P<0.05), and the body weight of male rats in the restraint group was lower than the control group (P<0.05) . Further analysis showed that for male rats there was significant difference between groups since the forth week (P<0.05), and the interaction was found between groups and test time (P<0.05) . For female rats, the interaction was found since the eighth week between the group and test time (P <0.05) .There was no significant differences in other parameters between two groups (P>0.05) . Conclusion Repeated restraint during dermal exposure affected the body weight gain of rats, and the sensitivity of male rats was higher than that of female rats.
ABSTRACT
Objective To understand the developmental effects induced by CdSe /ZnS quantum dots(QDs)on zebrafish embryos.Methods Zebrafish embryos were exposed to 0,0.5,1,2,4,8 and 16 nmol/L of CdSe /ZnS QDs,and the typical toxicological indexes were recorded at five time points respectively (24 hours post fertilization (hpf),48 hpf, 72 hpf,96 hpf,120 hpf).Results The results showed that the median lethal concentration (LC50 )for zebrafish embryos after 120 hpf was 21.38 nmol/L(95% CI =17.21 -26.57).The frequency of spontaneous movement in 60 seconds after 24 hpf,the frequency of heart beat in 60 seconds after 48 hpf,the hatching rate and the mortality rate were obviously affected by CdSe /ZnS QDs.Several abnormalities and toxic symptoms caused by CdSe /ZnS QDs at 8 nmol/L and 16 nmol/L were observed including pericardial edema,liver atrophy,non -depleted yolk,intestinal abnormal development and muscle degeneration after 120 hpf.Conclusion High level of CdSe /ZnS QDs (more than 8 nmol/L)could induce toxic effects on zebrafish embryonic development.
ABSTRACT
Objective To evaluate acute toxicity and genotoxicity of sapindus saponin and to provide toxicological basis for sapindus saponin ’s daily applications. Methods Acute oral toxicity test,mammalian erythocyte micronucleus test, bacterial reverse mutation test and in vitro mammalian chromosome aberration test were used to investigate the effect of the sapindus saponin on gene mutation and chromosome aberration in both prokaryotic and eukaryotic cells. Results The acute toxicity test showed that the LD50 of sapindus saponin was 4640 mg/kg for both male and female mice. Toxic symptoms were observed including salivation,mucus and other toxic manifestations. There was no significant difference between the each dose group and the negative control group in the results of mammalian erythocyte micronucleus test( P>0. 05). The results of bacterial reverse mutation test were also negative. In each dose group and strain with or without S9,the number of revertant colonies did not exceed 2 times than that of spontaneous revertant colonies( negative control). No dose-response relationship was observed. The vitro mammalian chromosome aberration test showed that the IC50 of sapindus saponin on CHL was 75 μg/ml,and the differences between each dose group and the negative control group were not statistically significant( P >0. 05 ). However,the positive control group differed from the negative control group in all tests( P <0. 01). Conclusion Under this experimental condition,sapindus saponin has no genotoxicity.