大气细颗粒物暴露后小鼠肺组织microRNA差异表达谱芯片分析

microRNAs作为临床疾病早期诊断的新型生物标记物越来越受到重视,为了进一步探究其在大气污染暴露后引起疾病的分子染毒机制。本研究通过建立大气污染小鼠染毒模型,利用Agilent芯片筛查小鼠肺组织中microRNAs差异表达谱,并通过实时荧光定量PCR方法验证芯片结果,使用Target Scan,PITA,microRNAorg数据对差异mi RNA进行靶基因预测,进行靶基因富集的基因功能(GO)和信号通路(KEGG)分析。结果显示,大气细颗粒物暴露2周后小鼠肺组织microRNAs有显著差异表达谱,高剂量暴露组与对照组比较有4个mi RNAs上调,低剂量暴露组与对照组比较有2个mi RNAs上调,高剂量组与低剂量组比较,有4个mi RNAs上调(标准为fold change值=2.0且P值=0.05),挑选差异明显的mi RNAs进行q RT-PCR验证,mi R-139-5p、mi R-691及mi R-340-3p变化趋势与芯片一致,生物信息学结果显示,差异表达的mi RNAs所调控的靶基因明显富集于34个GO通路(包括RNA转录酶II启动子的转录,RNA拼接,DNA模板,蛋白质结合和核酸结合)和32个KEGG通路(主要集中轴突导向通路和癌症通路)。综上所述,大气细颗粒物暴露染毒可诱导小鼠肺组织中mi R-139-5p、mi R-691及mi R-340-3p明显上调,且生物信息学分析提示中枢神经系统发育及癌症通路可能作为PM2.5暴露相关差异表达mi RNAs调控靶基因介导的主要致病通路。     

胚胎期和哺乳早期全氟辛烷磺酸盐(PFOS)暴露对大鼠肝脏脂肪酸代谢影响的microRNA组学研究

研究低剂量全氟辛烷磺酸(perfluorooctane sulfonate,PFOS)对大鼠幼仔肝脏中microRNA的表达及脂肪酸代谢的影响,并且从microRNA分子角度探讨PFOS对肝脏相关功能影响的分子毒性机制及预测其他一些潜在的毒性效应。PFOS染毒剂量为3.2mg·kg-1,对照组给予同等体积的含2%的聚氧乙烯山梨糖醇酐单月桂酸酯乳化剂(Tween 20),利用高通量miRNA芯片技术观察了胚胎期和哺乳早期经PFOS染毒后出生第1和7天(PND1和PND7)大鼠肝脏组织miRNA的表达情况。结果显示,PFOS能够引起仔鼠肝脏microRNA表达量的变化,PND1和PND7时显著变化的microRNA个数分别为46和9个。miR-125a-3p、miR-23a*、miR-25及miR-494同时在PND1和PND7显著性表达,PND1呈现下调性变化,PND7呈现上调性变化。通过生物信息学和统计学分析发现:PFOS具有大鼠肝脏早期发育毒性,而且胚胎期的毒性效应强于哺乳早期;大鼠幼仔肝脏早期发育中,PFOS对其糖脂代谢及细胞凋亡过程具有毒性效应;胚胎期和哺乳早期,在低剂量PFOS暴露下,β和ω氧化代谢是肝脏脂肪酸代谢的主要方式;脂酰COA合成酶、脂酰COA脱氢酶及烯酰COA水合酶等脂肪酸代谢过程的关键酶,是PFOS暴露下microRNA潜在的靶分子。研究表明,PFOS具有多种肝脏早期发育毒性,低剂量PFOS暴露下,microRNA能够调节肝脏脂肪酸代谢相关靶基因的表达,进而调控脂肪酸代谢过程。     

胚胎期及哺乳期全氟辛烷磺酸盐(PFOS)暴露对大鼠长时程突触可塑性影响的miRNA组学研究

为探讨PFOS胚胎期及哺乳期暴露对动物子代学习记忆能力影响的分子机理,采用微小RNA(miRNA)芯片技术检测PFOS胚胎期及哺乳期暴露对出生第1和7天大鼠脑组织miRNA表达的影响,分析突触可塑性相关miRNA表达的差异变化。结果显示,经PFOS暴露后出生第1和7天的大鼠脑组织中分别有24和17个miRNA发生显著性差异表达(p<0.05),其中与突触传递和神经递质转运等相关的miRNA的差异表达最为显著,主要包括miR-466b、miR-672、miR-297、miR-674-3p和miR-207。差异表达miRNA的路径分析显示出生后1和7d的大鼠的长时程增强效应(LTP)均受PFOS显著影响(p<0.05),这说明PFOS胚胎期及哺乳期暴露可能通过影响LTP的形成、发展和维持过程对大鼠子代大脑学习记忆能力造成威胁,并且miR-466b、miR-672、miR-297、miR-674-3p和miR-207可能参与了其中的调控过程。     

Renal lesions in Greenland sledge dogs ( Canis familiaris ) exposed to a natural dietary cocktail of persistent organic pollutants

Persistent organic pollutants such as Polychlorinated biphenyls (PCB) and dichloro diphenyl trichloroethane (DDT) are known to exert various adverse health effects in wildlife mammals. The impact from dietary intake of minke whale (Balaenoptera acutorostrata) blubber high in organohalogen and other chemical contaminants on renal morphology and function was investigated via a controlled study on West Greenland sledge dogs (Canis familiaris). Our results showed significantly higher frequencies of glomerular, tubular, and interstitial lesions in the exposed group. Furthermore, higher urine protein?:?creatinine ratio and plasma urea levels were found in the exposed group, which indicated a negative impact on kidney function via tubular and glomerular dysfunctions. The lesions were similar to those observed in top predator marine species–such as seals and polar bears–and humans exposed via diet to persistent environmental pollutants. The lesions may have impacts on the overall health of these animals. It is reasonable to suggest that chronic exposure to organic pollutants via a country diet of high trophic level marine organisms may have an impact on renal morphology and function in Arctic apex predators in general as well as Inuit people.     

Pollution distribution of heavy metals in surface soil at an informal electronic-waste recycling site

We studied distribution of heavy metals [lead (Pb), copper (Cu) and zinc (Zn)] in surface soil at an electronic-waste (e-waste) recycling workshop near Metro Manila in the Philippines to evaluate the pollution size (spot size, small area or the entire workshop), as well as to assess heavy metal transport into the surrounding soil environment. On-site length-of-stride-scale (~70 cm) measurements were performed at each surface soil point using field-portable X-ray fluorescence (FP-XRF). The surface soil at the e-waste recycling workshop was polluted with Cu, Zn and Pb, which were distributed discretely in surface soil. The site was divided into five areas based on the distance from an entrance gate (y-axis) of the e-waste recycling workshop. The three heavy metals showed similar concentration gradients in the y-axis direction. Zn, Pb and Cu concentrations were estimated to decrease to half of their maximum concentrations at ~3, 7 and 7 m from the pollution spot, respectively, inside the informal e-waste recycling workshop. Distance from an entrance may play an important role in heavy metal transport at the soil surface. Using on-site FP-XRF, we evaluated the metal ratio to characterise pollution features of the solid surface. Variability analysis of heavy metals revealed vanishing surficial autocorrelation over metre ranges. Also, the possibility of concentration prediction at unmeasured points using geostatistical kriging was evaluated, and heavy metals had a relative “small” pollution scales and remained inside the original workshop compared with toxic organohalogen compounds. Thus, exposure to heavy metals may directly influence the health of e-waste workers at the original site rather than the surrounding habitat and environmental media.     

中国电子废物处理处置典型地区污染调查及环境、生态和健康风险研究进展

电子废物含有大量的金属、塑料和阻燃剂等物质,如果处理不当,电子废物将向环境排放种类繁多的有毒有害物质,从而产生严重的环境污染问题。近年来,国内外学者对电子废物处理所致的生态环境问题给予了相当的关注,已经开展了不少相关研究,这些研究主要集中在我国的几个电子废物处理处置典型地区。本文对近5年来的相关研究成果进行了系统综述,内容涉及电子废物处理处置过程中产生的主要环境污染物,电子废物处理处置活动所致的土壤、水体和大气的重金属和持久性有机污染物污染以及电子废物处理处置活动对动植物和人体的污染风险等,并提出将来关于电子废物研究中需要关注的问题。     

Polychlorinated biphenyls and their hydroxylated metabolites in the serum of e-waste dismantling workers from eastern China

A number of studies have reported on the exposure of e-waste dismantling workers to significantly high concentrations of halogenated organic pollutants such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers. Such exposure can have adverse health effects. However, little information on the metabolites of these contaminants exists. In this study, we investigated PCBs levels and their hydroxylated metabolites (OH-PCB) in the serum of e-waste workers in Taizhou in eastern China. Our results indicate elevated PCB and OH-PCB levels in the serum of the workers, with medians of 443.7 and 133.9 ng/g lw, respectively. Tri- to hexachlorinated PCB congeners were the dominant homologue groups in all of the samples. 4-OH-CB107 was the predominant homologue among the hydroxylated metabolites, accounting for 88.9% of the total OH-PCB concentrations. While dietary sources (e.g., fish) appear to be an important route for PCB accumulation in non-occupational exposure groups, exposure via ingestion of house dust and inhalation of pollutants derived from the recycling of PCB-containing e-wastes may primarily contribute to the high body burden observed in the occupational groups. Since we found concentrations of metabolites higher than those of their parent compounds, further studies need to pay more attention to their bioaccumulation and toxicity.     

MiRNA-451 is a potential biomarker for estrogenicity in mouse uterus

The uterotrophic assay has been commonly used to test environmental estrogens in vivo, however, it is often not sensitive enough sometimes. An alternative way is to evaluate estrogenicity through biomarker genes. MicroRNA （miRNA） is a class of regulatory gene, which has been shown to be a good biomarker for many diseases and toxicological effects in recent years, and some evidences showed that estrogen induced response was partially mediated by miRNAs. In this study, two types of microarrays were used to test the 17[3-estradiol （E2） induced miRNA expression profile at different time points in the immature mouse uterus. Statistical analysis showed the aldehyde slide based array had less variation than the amino slide based array, and 11 dysregulated miRNAs were screened out for significant fold change. Real-time PCR was performed to further confirm that 4 out of 7 selected miRNAs, namely miR-451, miR-155, miR-335- 5p, and miR-365, are E2 regulated miRNAs in the uterus. The function of the predicted targets of these miRNAs is involved in cell grow control, which is consistent with the main E2 function in the uterus. MiR-451 had similar strong responses to E2 in the uterus of both immature and overiectomized mice, and could be a potential biomarker for estrogenicity in the uterus.     

广东清远电子垃圾处理地沉积物对伸展摇蚊的慢性毒性效应

电子垃圾拆解引起的环境污染和生态风险已成为全球关注的热点问题,不适当的电子垃圾拆解过程造成处理区水体沉积物受到多类有机化合物和重金属污染,直接威胁生活在沉积物中的底栖动物。在典型电子垃圾处理地广东清远采集沉积物,测定样品中以烃类为主的色谱难分离混合物(unresolved complex mixture,UCM)的含量,开展伸展摇蚊全生命周期慢性毒性测试。结果表明,清远沉积物中的UCM浓度(0.08±0.01)%接近于这类污染物对伸展摇蚊的慢性半致死性效应浓度(0.073±0.022)%。同时发现清远沉积物对以摇蚊为代表的底栖无脊椎动物具有显著慢性毒性效应,且可通过测定UCM含量初步估算。这为开展以电子垃圾处理地沉积物为代表的,受到以麻醉作用为主要致毒机制的混合物污染的沉积物的毒性评价提供了一种有效方法。     

电子垃圾拆解对台州氯代/溴代二噁英浓度和组成的影响

电子垃圾拆解会导致有毒有害污染物向大气的排放,造成环境污染的产生。为了解电子垃圾拆解及废旧金属再生活动对拆解地及邻近地区空气质量的影响,对台州峰江金属再生园区附近及对照区路桥市区大气中(气态和颗粒态)氯代二噁英(PCDD/Fs)、溴代二噁英(PBDD/Fs)的含量、同系物组成及气/固分配规律进行了研究,通过相关性分析探讨了PCDD/Fs和PBDD/Fs的可能来源。结果显示,金属再生园区冬季采样期间17种2,3,7,8-PCDD/Fs和8种2,3,7,8-PBDD/Fs的平均浓度分别为212.2 pg·m-3和17.6 pg·m-3,夏季采样期间的平均浓度分别为84.5 pg·m-3和5.4 pg·m-3,均显著高于对照点。夏季采样期间对照点处于再生园区的下风向,其二噁英浓度高于冬季,说明其受到了金属再生园区的明显影响。基于相关性分析的结果,塑料焚烧是金属再生活动中氯代和溴代二噁英的主要来源。初步的暴露风险评价表明,金属再生园区附近居民每日摄入的二噁英含量远远超过世界卫生组织规定的人体每日耐受量(1~4 pg W-TEQ·kg-1·d-1)。上述研究结果为规范电子垃圾拆解活动提供了基础数据。     

兰州地区人群对多环芳烃的暴露及健康风险评价

采用多介质-多途径暴露模型,评价兰州地区居民暴露于多环芳烃的健康风险,分析风险来源、暴露介质及暴露途径,并结合蒙特卡罗方法分析研究过程中的不确定性。结果表明,兰州地区居民中男性和女性对环境中多环芳烃的终身日平均暴露量分别为4.55×10-4和5.07×10-4mg.kg-1.d-1。暴露途径中食物摄取是最主要途径,食物中贡献较大的为谷物。相应的男性和女性的健康风险度分别为4.12×10-5.a-1和4.80×10-5.a-1,兰州地区多环芳烃类污染物居民人体健康风险度远远高于可接受健康风险度的标准。兰州地区女性对多环芳烃的暴露量高于男性,女性健康风险平均值亦远远高于EPA标准值,兰州地区女性乳腺癌发病率较高可能与长时间低剂量多环芳烃暴露有一定的关系。兰州地区多环芳烃人群暴露与天津和北京相比存在一定的差异。     

Air pollution and body burden of persistent organic pollutants at an electronic waste recycling area of China

Environmental Geochemistry and Health - This paper reviews the concentrations of persistent organic pollutants (POPs) in atmosphere of an electronic waste (e-waste) recycling town, Guiyu, in...     

MicroRNA:POPs诱导动脉粥样硬化的潜在调控者

目前动脉粥样硬化在全世界以惊人的速度增长,成为21世纪公共健康的严重挑战。持久性有机污染物(persistent organic pollutants,POPs)具有生物富集性和持久性,可通过各种环境介质对人体健康产生危害。研究表明POPs能够改变基因表达,加速动脉粥样硬化的发生发展,因而POPs被认为是动脉粥样硬化的致病风险因素之一。MicroRNAs(miRNAs)是生物进化过程中高度保守的一组非编码小分子RNA,在转录后水平调节基因的表达。miRNAs的差异表达涉及一系列疾病的生理和病理过程。有证据显示,POPs能够引起生物体内miRNAs的表达紊乱,从而引起基因的差异表达。大量文献报道也显示miRNAs在动脉粥样硬化中起重要作用。因此,POPs可能通过miRNA的潜在调控从而导致动脉粥样硬化的发生发展。     

Testosterone concentrations and male genital organ morphology in Greenland sledge dogs (Canis familiaris) dietary exposed to organohalogen contaminants

This study investigated whether low-level, long-term in utero and post-natal exposure to organohalogen pollutants disrupts male reproductive organ morphology and testosterone production in Greenland sledge dogs (Canis familiaris), as a model of Arctic top predators feeding on marine mammals. Six male dogs were followed for 1 year and testosterone concentrations, testes/baculum morphology and baculum bone mineral density (BMD) was determined. Three males were exposed to organohalogenated contaminants (OHCs) in utero through maternal dietary intake of minke whale blubber (Balaenoptera acutorostrata), with a post-weaning ∑OHC intake of 10.4–11.7 µg kg^?1 day^?1 resulting in an adipose tissue range of ∑OHC 4518–5729 ng (g lw)^?1 after 1 year. Three control males were exposed to very low concentrations of OHCs through pork fat. No significant differences were seen in plasma testosterone concentrations, baculum weight, BMD, and testicular length in the six male dogs (control, n = 3 and exposed, n = 3) measured at 3, 5, 7, 9, and 12 months of age. Testicular weights were significantly lower in the exposed group (p = 0.015, n = 2). Although this study had a limited number of animals, it was observed that in utero and the following 12 months of chronic exposure to a complex mixture of contaminants in the form of naturally accumulated OHCs does not affects testosterone levels, but possibly affects testicular weights in sledge dogs.     

PBDEs and PCDD/Fs in surface soil taken from the Taizhou e-waste recycling area,China

The emerging issue of electronic wastes (e-waste) and the associated environmental problems has gained considerable attention from the scientific community in recent decades. In the present study, the levels of polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the surface soil obtained from the Taizhou e-waste recycling area of China were investigated. Also the correlation among these chemicals and previously published data of heavy metals, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls was analysed. We determined that the pollution levels of eight PBDEs congeners were serious, ranging from 27.9 to 3128.4 μg/kg. The concentration of PCDD/Fs was in the range of 218.3–3122.2 pg/g with a mean value of 659.5 pg/g. The PBDEs were not well-correlated with organic pollutants (PAHs and PCBs) in soil, whereas PCDD/Fs exhibited a significant positive correlation with the PCBs. The higher levels of persistent organic pollutants may pose potential adverse effects to soil quality and human beings and needs to be properly managed and remediated.     

Genotoxicity and mutagenicity of electronic waste leachates using animal bioassays

Human exposure to electronic waste (e-waste) is increasing, especially in developing nations. This has potential short and chronic adverse health risks. Information is currently scarce on potential genotoxicity of e-waste leachate. In this study, the potential mutagenic and genotoxic effects of leachates from e-waste dumpsites at two electronic markets in Lagos, Nigeria, were investigated. The assays utilized were: bone marrow micronucleus (MN) and chromosome aberration (CA), spermatogonia CA, sperm morphology, and sperm count in mice. Experiments were carried out at concentrations of 1%, 5%, 10%, 25%, and 50% (v/v; leachate: distilled water) of leachate samples. MN analysis showed a concentration-dependent induction of micronucleated polychromatic erythrocytes (MNPCE) across the treatment groups. In the CA tests (bone marrow and spermatogonia), there was concentration-dependent significant reduction in mitotic index and induction of different types of CA. Assessment of sperm shape showed a significant increase in sperm abnormalities with significant decrease in mean sperm count in treated groups. Heavy metals analyzed in the tested samples are believed to contribute significantly to the observed genetic damage. This indicates that e-waste contains potential genotoxic agents; and constitutes a genetic risk in exposed human population.     

Serum Iron Concentrations, Lipid Peroxidation and Superoxide Dismutase Activity in Turkish Iron Miners

The effects of iron exposure, on serum iron, serum superoxide dismutase (SOD), a free radical scavenger, and plasma malondialdehyde (MDA), a lipid peroxidation parameter, were investigated in Turkish iron miners, office workers and healthy control subjects. Serum iron levels in both miner and office workers groups were higher than those of healthy controls (p < 0.05). There were higher mean values of plasma MDA levels in both iron miners and office workers compared to controls (p < 0.05). Serum SOD activity in the miner group was lower than that of controls (p < 0.05). These results suggested that elevated MDA levels in both miners and office workers were the result of an increased production and/or decreased catabolism of MDA in chronic iron exposure. These changes in MDA metabolism may be due to iron-induced lipid peroxidation in the blood and related body compartments.     

Polybrominated diphenyl ethers in plastic products,indoor dust,sediment and fish from informal e-waste recycling sites in Vietnam: a comprehensive assessment of contamination,accumulation pattern,emissions, and human exposure

Residue concentrations of polybrominated diphenyl ethers (PBDEs) in different kinds of samples including consumer products, indoor dust, sediment and fish collected from two e-waste recycling sites, and some industrial, urban and suburban areas in Vietnam were determined to provide a comprehensive assessment of the contamination levels, accumulation pattern, emission potential and human exposure through dust ingestion and fish consumption. There was a large variation of PBDE levels in plastic parts of obsolete electronic equipment (from 1730 to 97,300 ng/g), which is a common result observed in consumer plastic products reported elsewhere. PBDE levels in indoor dust samples collected from e-waste recycling sites ranged from 250 to 8740 ng/g, which were markedly higher than those in industrial areas and household offices. Emission rate of PBDEs from plastic parts of disposed electronic equipment to dust was estimated to be in a range from 3.4 × 10^?7 to 1.2 × 10^?5 (year^?1) for total PBDEs and from 2.9 × 10^?7 to 7.2 × 10^?6 (year^?1) for BDE-209. Some fish species collected from ponds in e-waste recycling villages contained elevated levels of PBDEs, especially BDE-209, which were markedly higher than those in fish previously reported. Overall, levels and patterns of PBDE accumulation in different kinds of samples suggest significant emission from e-waste sites and that these areas are potential sources of PBDE contamination. Intakes of PBDEs via fish consumption were generally higher than those estimated through dust ingestion. Intake of BDE-99 and BDE-209 through dust ingestion contributes a large proportion due to higher concentrations in dust and fish. Body weight normalized daily intake through dust ingestion estimated for the e-waste recycling sites (0.10–3.46 ng/day/kg body wt.) were in a high range as compared to those reported in other countries. Our results highlight the potential releases of PBDEs from informal recycling activities and the high degree of human exposure and suggest the need for continuous investigations on environmental pollution and toxic impacts of e-waste-related hazardous chemicals.     

电子垃圾拆解区土壤中典型手性PCBs分布及对映体特征

龙塘镇位于广东省清远市,是国内最大的进口电子垃圾集中处理处置地之一.通过对龙塘镇土壤中7种手性PCBs对映体浓度和对映体百分数(enantiomer fractions,EF)值的测定,发现龙塘镇土壤样品除PCB45和PCB174外,其余5种手性PCBs在土壤中均有不同程度的检出.土壤中5种目标手性PCBs(PCB91、PCB95、PCB132、PCB136和PCB149)的总浓度为145.4—286.7 ng·g^-1,这与先前文献中测定清远市土壤中手性PCBs污染水平基本一致.5种同系物的含量排序为PCB95>PCB132>PCB136>PCB149>PCB91.在距离电子垃圾拆解区10km以外的区域也检测到手性PCBs,证实这些污染物已经迁移到周边地区.土壤中手性PCB91、PCB95、PCB132、PCB136和PCB149的EFs值分别为0.519±0.005、0.4443±0.006、0.427±0.003、0.379±0.016和0.494±0.008,其中PCB149具有双向选择性.在全部检出样品中26%的PCB91、78%的PCB95、100%的PCB132、86%的PCB136和53%的PCB149具有非外消旋特征,表明该地区土壤中手性对映体选择性降解的显著性.     

Screening of thyroid gland histology in organohalogen-contaminated glaucous gulls (Larus hyperboreus) from the Norwegian Arctic

The associations between blood organohalogen contaminant (OHC) concentrations and thyroid gland histology were studied in 10 adult female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic (Bjørnøya) during the incubation period. This histological investigation was undertaken as previous glaucous gull studies from the same area reported negative relationships between circulating OHC concentrations and thyroid hormone levels. Organohalogen concentrations have previously been associated with altered blood plasma thyroid hormone concentrations, as a result of parenchymal thyroid gland alterations and perturbation of the hypothalamic-pituitary-thyroid (HPT)-axis. In this study, PCB (range: 186–1027 ng g^?1ww), DDT (77–203 ng g^?1ww) and chlordane (18–65 ng g^?1ww) concentrations dominated the blood plasma OHC profile in incubating female glaucous gulls. High density of small follicles accompanied by follicular epithelial cell proliferations was seen in thyroid glands in seven of 10 gulls. Focal thyroiditis and nodular hyperplasia were found in two birds. No significant differences in plasma OHC concentrations were noted between gulls exhibiting high density of small follicles and cell proliferations and those birds not showing histological changes. Based on these findings, data suggest that the histological changes in thyroid glands of OHC-contaminated female glaucous gulls may be due to natural variance, although an OHC-induced thyroid stimulating hormone (TSH) perturbation resulting in epithelial cell hyperplasia and increased follicular density cannot be ruled out and remains to be verified. Hence, a large-scale histological study is required, in order to elaborate the potential linkage between changes in thyroid gland histology, OHC exposure and regulation of the HPT-axis in the Arctic-breeding glaucous gull.