肢芽细胞微团培养评价饮水中有机物致畸性

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

目的应用大鼠肢芽细胞微团培养技术快速评价饮用水中有机物的致畸性,并比较氯化消毒过程对致畸作用的影响。方法XAD-4树脂富集、浓缩饮用水中有机物,连续5 d微团培养d13大鼠肢芽细胞,根据半数分化抑制浓度(ID50)和半数增殖抑制浓度(IP50)及IP50/ID50比值判定有机浓集物的致畸性。结果在较低剂量范围内,管网末梢水中有机物对大鼠肢芽细胞的分化有明显的抑制作用,ID50分别为363.1 ml/ml(-S9)和5.67 ml/ml(+S9);IP50分别为1355.2 ml/ml(-S9)和1264.5 ml/ml(+S9),IP50/ID50=3.7(-S9);IP50/ID50=223(+S9),显示该组分特异性抑制肢芽细胞的分化,经代谢转化后其ID50降低达63倍;原水中有机浓集物的ID50分别为1.17 ml/ml(-S9)和0.387 ml/ml(+S9);IP50分别为15.8 ml/ml(-S9)和41.1 ml/ml(+S9);IP50/ID50=13.5(-S9);IP50/ID50=106.2(+S9),代谢活化增加该组分的抑制分化作用。结论管网末梢水及原水中有机浓集物属特异性细胞分化抑制物,具有潜在的直接和间接致畸性,为潜在的强致畸原,显示多种致畸机制。氯化消毒过程可能增加饮用水中有机物的间接致畸作用。

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 1.2 rnl/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.