Evaluation of reproductive and developmental toxicities of Pu-erh black tea (Camellia sinensis var. assamica) extract in Sprague Dawley rats

Ethnopharmacological relevance: Pu-erh black tea, which is obtained by first parching crude green tea leaves and followed by secondary fermentation with microorganisms, has been believed to be beneficial beverages for health in PR China. But its potential toxicity when administered at a high dose as concentrated extract has not been completely investigated.

Aim of the study: The present study was aimed at evaluating potential reproductive and developmental toxicities of Pu-erh black tea extract (BTE) in Sprague Dawley rats.

Materials and methods: Growing rats were given BTE by gavage at levels of 0, 200, 700 and 2500mg/kg/day as the F0 generation in reproductive toxicity study. Additionally, BTE was administered to mate female rats from gestation day 0.5 through 19.5 at the doses of 0, 200, 700 and 2500mg/kg/day to evaluate the developmental toxicity.

Results: In the reproductive toxicity study, only 2500mg/kg/day BTE reduced the body weight gain and altered the relative organ weights including testes, prostata and ovary both for F0 parents and F1 offspring compared to the controls. High dose of BTE (2500mg/kg/day) administration caused developmental disturbances in embryo-to-foetus period including resorbed embryos, decreased embryo size and skeletal anomalies.

Conclusion: In conclusion, the no-observed-adverse-effect level of BTE is 700mg/kg/day both for reproductive toxicity and developmental toxicities.