With increasing use of municipal solid waste landfills for waste disposal, the leachate generated has become a serious environmental concern. Therefore, it is important to set up simple and accurate methods for monitoring leachate toxicity. In the present study, the physiological and genetic toxicity of the leachate, generated from Xingou Municipal Landfill in China, were investigated with Triticum aestivum (wheat) bioassay. The results indicate that the lower leachate concentrations stimulated the germination, growth and cell division, and did not induce obvious increase in micronucleus (MN) frequency in root tips; while the higher concentrations inhibited the processes, and significantly augmented the MN frequency in a concentration-and time-dependent manner. In addition, pycnotic cells (PNC) and sister chromatid exchange (SCE) occurred in root tips at all leachate concentrations tested, and the frequencies had positive relation with the treatment concentration and time. The results imply that components of leachate from the landfill may be genotoxic in plant cells, and exposure to leachate in the aquatic environment may pose a potential genotoxic risk to organisms. The results also suggest that the wheat bioassay is efficient, simple and reproducible in monitoring genotoxicity of the leachate.

The genotoxicity of municipal landfill leachate was studied using the Vicia faba root-tip cytogenetic bioassay. Results show that landfill leachates collected in different seasons decreased the mitotic index (MI) and caused significant increases of micronucleus (MN) frequencies and anaphase aberration (AA) frequencies in a concentration-dependent manner (concentration expressed as 'chemical oxygen demand' measured by the method of potassium dichromate oxidation (CODCr)). In addition,a seasonal difference in genotoxicity induced by leachate was observed. The results confirm that leachate is a genotoxic agent in plant cells and imply that exposure to leachate in the aquatic environment may pose a potential genotoxic risk to organisms. The results also show that the V. faba cytogenetic bioassay is efficient, simple and reproducible in enotoxicity studies of leachate, and that there is a correlation between the genotoxicity and the chemical measurement (CODCr) of leachate.

The cytogenetic damage induced by municipal landfill leachate was studied using chromosomal aberration (CA) in mouse bone marrow assay. Results show that leachate samples collected in different seasons decreased the mitotic index (MI), and caused significant increases of CA frequencies in treatment concentration (Chemical oxygen demand (COD) measured by the method of potassium dichromate oxidation, CODCr)-dependent manners. Compared with the negative control, reductions of the MI of 54 and 38% were detected for the highest leachate concentration (CODCr 320mg/L) in mouse bone marrow treated with both samples. The frequencies of CA increased significantly with increasing concentrations of sample 1 from CODCr 40 to 320mg/L, and from 80 to 320mg/L after exposure to sample 2. In addition, aseasonal difference of MI and CA frequencies induced by leachate was observed. The results confirm that leachate is a genotoxic agent in mammalian cells, and imply that exposure to leachate in aquatic environment may pose a potential genotoxic risk to mammals and humans. The results suggest that the CA in mouse bone marrow bioassay is efficient in genotoxicity studies of leachate on mammals, and that there appears to be a correlation between the genotoxicity in mammal system and the chemical measurement (CODCr) of leachate. The results also indicate that different discharge guidelines and environmental quality standards should be established for eachates discharged from landfills to aquatic environment in different seasons.

生活垃圾填埋场渗滤液是指在垃圾堆放和填埋过程中由于发酵和雨水淋溶、冲刷以及地表水和地下水的浸泡而渗滤出来的污水，其中不仅含有大量的有机物、氨氮和重金属，同时含有多种微生物、致病菌和病毒等，是一种营养物质与有毒物质共存的高浓度难降解有机废水。渗滤液的形成和渗漏可造成填埋场周边地区地表水和地下水的严重污染，甚至危害公共健康。为此，本文研究了渗滤液对高等植物（玉米和大麦）和哺乳动物（昆明种小鼠）的毒性作用。结果表明，渗滤液对玉米和大麦种子萌发、幼苗生长和细胞有丝分裂均具有低浓度促进和高浓度抑制的效应，并可浓度和时间依赖性地诱导植物幼苗根尖细胞中微核、核固缩和核碎解、染色体后期异常、姐妹染色单体交换等遗传物质损伤的发生。哺乳动物实验结果表明，渗滤液可引起小鼠骨髓微核嗜多染红细胞中微核率浓度依赖 性地增加，改变不同组织器官（心、脑、肝、肺和肾）抗氧化酶活性，诱导脂质过氧化和蛋白氧化的发生。上述结果提示，生物毒性检测指标应纳入对渗滤液污染的控制和评价体系中。

焦化废水是煤高温干馏、煤气净化、副产品回收与精制过程中产生的难降解工业有机废水，其中含有大量的氨、氰、硫氰根、氟化物等无机污染物，同时还含有酚、油、胺、萘、吡啶、喹啉、葸等杂环及多环芳香族化合物（PAHs），组分复杂、污染物浓度高。这一水质特征决定了焦化废水的生物处理效果有限，理化处理成本高。在此基础上，有研究者提出利用植物-土壤系统进行修复，但其关键在于植物能否耐受焦化废水造成的环境胁迫。为此，本文以北方常见植物玉米为实验材料，探讨焦化废水对其生长和抗氧化系统的影响，旨在阐明焦化废水污染土壤植物修复的可行性。结果表明，一定浓度焦化废水可降低根尖细胞有丝分裂指数，影响植株生长；诱导超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）活性增加，提高了抗坏血酸（AsA）和谷胱甘肽（GSH）含量；高浓度则可造成脂质过氧化和蛋白质氧化的损伤。结果提示，焦化废水胁迫可引起植物生长和体内抗氧化系统的变化，但此作用存在浓度和时间依赖性关系，为探讨焦化废水污染的植物修复提供了实验依据。