卡维地洛对顺铂所致大鼠肾毒性预防作用的形态学研究

目的研究有机氯农药滴滴涕(dichlorodiphenyltrichloroethanes,DDTs)对唐鱼的急性毒性,评价水环境中DDTs对鱼类的影响,为渔业部门制定水质标准提供参考。方法使用浸浴法以0.0125、0.025、0.045、0.08和0.14mg/L五个DDTs浓度为唐鱼染毒,计算其对仔鱼的急性毒性及安全浓度。结果DDTs对唐鱼仔鱼为剧毒物质,24、48h的LC50分别为0.243、0.049mg/L,其安全质量浓度为0.040mg/L。结论唐鱼对DDTs敏感,可以作为一种较理想的环境污染指示生物。     

Concentrations of dioxins and other organochlorines (PCBs,DDTs, HCHs) in human milk from Seveso,Milan and a Lombardian rural area in Italy: a study performed 25 years after the heavy dioxin exposure in Seveso

AIM: To investigate whether those who were exposed to high levels of the dioxin TCDD 25 years ago in Seveso, northern Italy still have higher than the expected levels of dioxins in their fat stores, and to investigate the concentrations of dioxins in the breast milk of mothers in Seveso and in two other regions in Italy. The load of vertically transmitted dioxins to the next generation, if being breastfed, was also investigated. METHODS: As there may be a synergistic effect of mixtures of organic chlorines, the concentrations of pesticides such as DDTs and PCBs have also been studied in the same human milk samples. Breast milk from 12 mothers from Seveso, Central Milan and a Lombardian village was collected for analysis during the first week and 1 and 3 mo after delivery. Individual samples were used for the analysis of pesticides and PCBs, whereas dioxins were analysed in pooled samples from all 12 mothers on each occasion. RESULTS: In human milk from Seveso, the TCDD concentration in fat calculated on a fresh weight basis was more than twice as high as the level in the other two regions, whereas the concentrations of investigated other toxins were lower in Seveso possible due to induction of the enzyme cytochrome P4501A, which means that the total level of dioxins was the same in all three locations. The congener profile, measured as mean toxic equivalency (TEQ) values, was the same in the Italian samples as previously reported from Stockholm. The calculations are based on the most recent WHO TCDD equivalency factors (TEF). The DDE concentration was higher in the samples from Milan than in the samples from the other two Italian regions, which may be due to the fact that, to a greater extent than in the other regions, Milanese food is imported from countries where DDT is still used as a pesticide. CONCLUSION: Twenty-five years after the dioxin catastrophe, human milk from mothers in Seveso has concentrations of the highly toxic dioxin congener TCDD that are more than twice as high as those in central Milan and a Lombardian village. This means that breastfed infants in Seveso still store an appreciable amount of TCDD in their body fat. The health consequences of this fact remain to be elucidated. The effect of the high load of DDTs in central Milan also has to be considered     

Assessment of PCBs exposure in human hair using double focusing high resolution mass spectrometry and single quadrupole mass spectrometry

Polychlorinated biphenyls (PCBs) levels were assessed in human hair samples, originating from two main agricultural regions of Greece. The analysis was performed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-double focusing high resolution mass spectrometry (GC-DFHRMS). The main analytical procedure involved hair decontamination, solid-liquid extraction and cleanup steps. The recoveries of PCBs ranged from 71.2% to 101.6%, with accuracies greater than 87.5% and the between-run precisions (%RSD) lower than 25% for all analytes. Differences in the frequencies of detection and the median values of PCBs were detected between the examined regions and between the applied analytical techniques. All Peloponnesus' hair examined samples were found positive for each examined PCB, while the percentage of the total positive samples ranged from 86.1% (for PCB 138) to 94.4% (for PCB 28 and 153 congeners) using GC-DFHRMS. The Cretan hair samples were less contaminated (SUM PCBs=0.61 and 1.47pg/mg) unlike the Peloponnesus' samples (SUM PCBs=24.68 and 38.74pg/mg) measured by GC-DFHRMS and GC-MS, respectively. PCBs with high chlorination gave lower concentration values compared to low chlorination PCBs in both populations. No significant differences were observed between women and men. The GC-DFHRMS technique provided higher percentage of positive samples and low PCBs median values, due to higher sensitivity and interferences from isobaric ions in the GC-MS technique and is therefore considered as a powerful tool for such assessments in hair specimens.     

Vertical Fluxes and Accumulation of Organochlorine Pesticides in Sediments of Haihe River,Tianjin, China

Organochlorine pesticides (OCPs) concentrations in sediments and sediment trap fluxes of particulate organic carbon and OCPs were measured from October 2006 to May 2008 in the urban reach of Haihe River, Tianjin, China, in order to investigate vertical fluxes and accumulation of OCPs in sediments. The concentrations of OCPs in sediments (dry weight basis) were in the range of 2.08–10.07 ng/g (mean 4.70 ng/g) for HCHs (α-, β-, γ-, δ-HCH), 5.82–43.39 ng/g (mean 17.43 ng/g) for DDTs (p,p′-DDE, p,p′-DDD, o,p′-DDT, p,p′-DDT). Compared with data reported in Haihe River 2003, the levels of OCPs showed a significant decrease between 2003 and 2008. This is mainly attributed to significant decrease of production and usage of HCHs and DDTs and biodegradation of HCHs and DDTs in sediment. Concentrations of HCHs and DDTs in sediments were well correlated with sediment organic carbon contents. Concentrations of OCPs in settling particles (dry weight basis) ranged from 21.2 to 138.4 ng/g (mean 52.6 ng/g) for HCHs, 30.0–245.7 ng/g (mean 87.1 ng/g) for DDTs, which were 2.2–48.2-fold higher than those associated with sediments. β-HCH was the dominant HCH isomer in both sediments and settling particles. Among DDTs, p,p′-DDE was found to be dominant in sediments, while p,p′-DDT was the predominant form in settling particles. This suggests that further biodegradation of OCPs occurred during the course of sedimentation and burial. The annual sediment trap flux of OCPs in Haihe River in the urban area of Tianjin was 177–211 μg/m² yr for HCHs and 213–341 μg/m² yr for DDTs, respectively.     

A case report of motor neuron disease in a patient showing significant level of DDTs, HCHs and organophosphate metabolites in hair as well as levels of hexane and toluene in blood

Motor neuron disease is a devastating neurodegenerative condition, with the majority of sporadic, non-familial cases being of unknown etiology. Several epidemiological studies have suggested that occupational exposure to chemicals may be associated with disease pathogenesis. We report the case of a patient developing progressive motor neuron disease, who was chronically exposed to pesticides and organic solvents. The patient presented with leg spasticity and developed gradually clinical signs suggestive of amyotrophic lateral sclerosis, which was supported by the neurophysiologic and radiological findings. Our report is an evidence based case of combined exposure to organochlorine (DDTs), organophosphate pesticides (OPs) and organic solvents as confirmed by laboratory analysis in samples of blood and hair confirming systematic exposure. The concentration of non-specific dialkylphosphates metabolites (DAPs) of OPs in hair (dimethyphopshate (DMP) 1289.4 pg/mg and diethylphosphate (DEP) 709.4 pg/mg) and of DDTs (opDDE 484.0 pg/mg, ppDDE 526.6 pg/mg, opDDD 448.4 pg/mg, ppDDD + opDDT 259.9 pg/mg and ppDDT 573.7 pg/mg) were considerably significant. Toluene and n-hexane were also detected in blood on admission at hospital and quantified (1.23 and 0.87 μg/l, respectively), while 3 months after hospitalization blood testing was found negative for toluene and n-hexane and hair analysis was provided decrease levels of HCHs, DDTs and DAPs.     

宁夏地表水环境中有机氯农药六六六和滴滴涕的残留现状与健康风险评价

目的了解宁夏地表水环境中有机氯农药的残留状况及对人体健康产生的潜在危害。方法于2013年3月,在宁夏南部地区选取16个水库、17个村庄的窖水;黄河宁夏段选取5个横断面,每个采样点采水6L,测定其中六六六类（HCHs）和滴滴涕类（DDTs）各异构体残留量;并对水中HCHs、DDTs所引起的健康风险作出评价。结果窖水中HCHs的含量范围在ND~8.46ng·L^-1,DDTs只在一个点检测到,含量为3.73ng·L^-1;水库水中HCHs的含量范围在ND~12.51ng·L^-1,DDTs只在一个点检测到,含量为3.08~7.40ng·L^-1;黄河水中只检测到了HCHs,含量范围在ND~2.51ng·L^-1。窖水、水库水、黄河水中HCHs和DDTs总的健康风险值分别为1.27×10^-12/年、3.36×10^-12/年、0.67×10^-12/年。结论宁夏地表水环境中仍有HCHs和DDTs残留,但低于地表水水质量标准限值;对人体潜在的健康危害很小。     

Metabolic impacts of high dietary exposure to persistent organic pollutants in mice

Persistent organic pollutants (POPs) have been linked to metabolic diseases. Yet, the effects of high exposure to dietary POPs remain unclear. We therefore investigated whether elevated exposure to POPs provided by whale meat supplementation could contribute to insulin resistance.     

气相色谱-串联质谱法测定滩涂生物样本中的六六六和滴滴涕

目的建立滩涂生物样本中的六六六(HCHs)和滴滴涕(DDTs)的气相色谱-串联质谱(GC-MS/MS)测定法。方法取可食部位匀浆样品加无水硫酸钠脱水、使用石油醚进行超声萃取,再加硫酸磺化后静置取有机相氮气吹干定容,取上清液经HP-5MS Ultra Inert毛细管气相色谱柱(30 m×250μm,0.25μm)分离,气相色谱-串联质谱分离检测,外标法定量。结果本法六六六和滴滴涕在0.100μg/L^10.0μg/L线性相关系数均≥0.999,方法检出限均为0.02μg/kg,平均样本加标回收率为57.6%~100%,相对标准偏差(RSD)在0.100μg/kg水平为15.1%~23.0%,1.00μg/kg水平为8.12%~17.1%,10.0μg/kg水平为3.22%~9.03%。使用本方法检测实际样品,六六六检出率为44.0%,滴滴涕检出率为99.0%,检出浓度为0.035μg/kg^8.17μg/kg。结论该方法前处理过程简便,定性及定量准确,灵敏度高,满足批量样品的检测。     

深圳市母乳中六六六和滴滴涕蓄积水平与影响因素分析

目的了解深圳市普通居民产妇母乳中六六六(HCHs)和滴滴涕(DDTs)的蓄积水平,并分析其影响因素,评估婴儿暴露风险。方法采集85位在深圳地区居住时间3年或以上、初产妇产后4～6周的母乳。样品经提取后,用凝胶渗透色谱和弗罗里硅土固相微萃取柱净化,采用气相色谱-电子俘获检测器(GC-ECD)检测母乳中六六六、滴滴涕(包括α-六六六、β-六六六、γ-六六六、δ-六六六、p,p’-滴滴涕、p,p’-滴滴滴、p,p’-滴滴异、o,p’-滴滴涕等8种同分异构体)的残留。通过问卷调查,分析母乳中六六六、滴滴涕的含量水平与产妇膳食情况、年龄、当地居住时间等因素进行相关性关系。结果所有母乳样品均检出p,p’-DDE,58份样品中检出β-HCH。母乳中∑HCHs的中位数为2.980ng/g(全重计),80.200ng/g(脂肪计)。∑DDTs的中位数为9.610ng/g(全重计),268.390ng/g(脂肪计)。统计分析发现,母乳中六六六、滴滴涕含量与产妇年龄、淡水鱼的消费量、禽肉的消费量呈正相关关系。结论深圳市居民母乳中检出了六六六、滴滴涕,其含量水平与年龄及膳食情况存在相关关系。婴儿六六六、滴滴涕的平均摄入估计值分别为0.468和1.842μg/(kg.d BW),均低于我国卫生部及FAO/WHO农药残留联席会议推荐的每日容许摄入量(ADI)。深圳市当地居民母乳中六六六和滴滴涕负荷水平低于全国平均水平。     

Comparative toxicity of hydrophobic contaminants to microalgae and higher plants

To enable rapid and sensitive screening of phytotoxic compounds in terrestrial system, a 4 day solid-phase microalgal bioassay was developed. Three species of microalgae (Selenastrum capricornutum, Chlorococcum hypnosporum and Chlorococcum meneghini) were chosen to investigate their responses to DDTs (DDT, DDD and DDE) and PAHs (naphthalene, phenanthrene and pyrene) spiked sands. The bioassay results showed that PAHs and DDTs were toxic to microalgae in a 4-day exposure tests but not to seed germination of ryegrass (Lolium perenne). Phenanthrene was the most phytotoxic. Among three investigated endpoints, fluorescence emissions by microalgae were less sensitive than cell density (optical density OD₆₅₀) and chlorophyll a concentration as endpoints. In general, S. capricornutum was the most sensitive species for PAHs (EC₅₀ for phenanthrene = 9.4 mg kg⁻¹), while C. meneghini for DDTs (EC₅₀ for DDE = 20.0 mg kg⁻¹). Comparison of the microalgal tests with US EPA standard seed germination/root elongation test (using Lolium perenne) demonstrated the superior screening potential of phytotoxic hydrophobic compounds using the proposed bioassay. Using OD₆₅₀ as the endpoint, EC₁₀ of selected microalgae for PAHs and DDTs were 0.43–64.3 mg kg⁻¹ and 0.67–117 mg kg⁻¹ respectively, which were much lower than the EC₁₀ of L. perenne for both PAHs (94–187 mg kg⁻¹) and DDTs (113–483 mg kg⁻¹). The results encourage further studies involving wider types of vascular plants and more comparison with standard phytotoxicity tests from different authorities using contaminated soils to verify the effectiveness of the microalgal bioassay.