Evaluation on organic teratogen of drinking water with micromass culture of rat embryo limb bud cells

  Objective   To screen rapidly the teratogenic contaminants which were extracted from raw drinking water and tap water in Hefei city. An in vitro short-term test was carried out.

  Methods   Organic contaminants were extracted from drinking water by use of XAD-4 macroreticular resins. With cultures of rat embryo limb bud cells for 5 days, the concentration inhibiting differentiation by 50% control(ID₅₀)and the concentration inhibiting proliferation by 50% control(IP₅₀)and the ratio of IP₅₀/ID₅₀ were gotten respectively by each inhibition curve.

  Results   The extractives inhibited the differentiation and the proliferation of limb bud cells. The ID₅₀ for tap water were 363. 1ml/ml(-S₉)and 5.7 ml/ml(+S₉), IP₅₀ were 1355.2 ml/ml(-S₉)and 1264.5 ml/ml(+S₉), the ratios for IP₅₀/ID₅₀(-S₉)were 3.7, IP₅₀(+S₉); IP₅₀ were 223;The ID₅₀ for raw water were 1.2ml/ml(-S₉)and 0.387 ml/ml(+ S₉); IP₅₀ were 15.8 ml/ml(-S₉)and 41.1 ml/ml(+S₉), the ratios for IP₅₀/ID₅₀ were 13.5(-S₉)and 106.2(+S\-9). That's to say, the extractives could be bioactivated into stronger inhibitors.

  Conclusion   There parameters indicated the influence of organic contaminants on differentiation of rat limb bud cells was stronger than on proliferation, and those organics in drinking water belonged to a teratogenic agent and a specific inhibittors. The chlorination of drinking water should be studied more extently.