摘要
本试验室在饮用水中首次发现了一种全新的氯化消毒副产物,通过实验室模拟氯化前驱物,分离提纯氯化产物,对其用各种现代分析手段进行结构表征,同时合成出该化合物,最终确定了其结构为2,2,4-三氯-5-甲氧基-环戊-4-烯-1,3-二酮（2,2,4-trichloro-5-methoxycyclopent-4-ene-1,3-dione,TCMCD）.TCMCD的分子结构中含有三个氯原子,可能存在着潜在的毒性,Ames初步毒性实验也表明TCMCD具有一定的致突变性,是一种碱基置换性的致突变物.本文研究了TCMCD对斑马鱼胚胎的急性毒性,结果表明,TCMCD对于斑马鱼胚胎有一定的致死性,浓度的差别对胚胎死亡率的影响很大,而且作用的时间有很大的不同,其LC50为36.7 mg/L;低浓度的TCMCD虽然不能100%致死,但是抑制孵化的作用非常明显,这也可能与TCMCD在胚胎中的积蓄有关.人体外周血淋巴细胞微核试验则说明,TCMCD在50～150 mg/L剂量范围内有明显的致突变作用,可对人体的遗传物质造成损伤.该物质在长期存在于饮用水中,具有一定的急性毒性和致突变性,需要进一步研究其累积性和慢性毒性,以评价其在饮用水中的存在对人体健康是否有构成威胁.
A new disinfection byproduct（DBP） was found in drinking water of a malignant tumor prevailing region in Jiangsu Province,China.We isolated the compound by chlorination and supposed its structure as 2,2,4-trichloro-5-methoxycyclopenta-4-ene-1,3-dione（TCMCD） using FTIR,MS,^1H NMR and ^13C NMR spectroscopic analysis and single-crystal X-ray diffraction.We also synthesized it and the structure was identified by analyzing and comparing FTIR,MS,^1H NMR and ^13C NMR spectrums of the synthetic and chlorinated products.The result confirmed the previously supposed structure of the new DBP.TCMCD was proved as a mutagen by Ames test with tester strain TA100.Therefore,there needs more research on it.We studied the acute toxicity on zebra fish embryo.Mature zebrafish（Danio rerio） were reared on a recirculating system in which the water was maintained at 26±1℃ and a pH between 6.8 and 8.0.Photoperiod was 14：10 h light： dark.Females and males were in a ratio of 1：2.The fish mated and spawned immediately after turning on the lights and fertilized eggs fell into the egg traps which were covered with stainless steel mesh with a grid size of 3mm and were collected about 30 min after the onset of light.Fertilized embryos were rinsed by embryo medium twice and exposed to series of TCMCD solutions as soon as possible.Embryo medium was a solution of essential salts added to deionized water.Every 24-well plate was an experimental group filled with the same concentration solution.In 20 wells,fertilized embryos were placed individually in 2 mL of test solution and the remaining 4 wells of each plate were filled with 2ml embryo medium.All embryos were incubated at 26±1℃ under a 14：10 h light： dark photoperiod.The result shows that the embryo mortality is influenced by different concentration of TCMCD,and LC50 is 36.7mg/L.Although low concentration could not cause 100% mortality,hatch restrained effect is obvious,which might be because of the cumulation of TCMCD in embryo.It is concluded that TCMCD is mortal to zebra fish embryo.The human peripheral blood lymphocyte micronucleus assay was conducted.Lymphocytes were obtained from a healthy male donor.The cultures of 0.5 mL whole blood were incubated at 37℃,which contained 4 mL of RPMI 1640 medium,1 mL foetal bovine serum,0.05 mL 100 Iu/mL penicillin,0.05 mL 100 Iu/mL streptomycin and 0.2 mL 25 μg/mL phytohemagglutinin.TCMCD of series concentration were added to cultures at 48 h after culture initiation.At the same time deionized water and mitomycin were also added negative and positive control.At 68 h after culture initiation,0.1 mL 40 μg/mL colchicine was added into the cultures.2 h later,chromosome preparations were made and stained with Giemsa solution.The results indicate that TCMCD is genotoxicity and could damage germ plasm of human being at the range of 50～150 mg/L.Therefore we conclude that TCMCD is toxicity and genotoxicity.Thorough research on accumulation and chronic toxicity is necessary to evaluate the safety of TCMCD in drinking water.
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2008年第1期71-76,共6页
Journal of Nanjing University（Natural Science）
基金
国家自然科学基金(20477015,2077032)
关键词
消毒副产物
斑马鱼胚胎
人体外周血
微核
disinfection byproduct,zebra fish embryo,human peripheral blood,micronucleus
