砒霜厂男性工人外周血淋巴细胞Fas和Bax基因表达水平与尿砷代谢产物的关系

目的探讨职业性砷暴露人群外周血淋巴细胞中Fas和Bax基因的表达与尿砷代谢产物之间的关系。方法于2011年10月,选取云南某砒霜厂全部43名职业性砷暴露男性工人为暴露组以及23名无砷暴露史男性人群为对照组。测定尿中无机砷、甲基胂酸、二甲基胂酸和外周血淋巴细胞Fas和Bax m RNA的表达水平。结果与对照组比较,砒霜厂工人尿中无机砷、甲基胂酸、二甲基胂酸、总砷及外周血淋巴细胞中Fas和Bax m RNA的表达水平均较高,二级甲基化指数较低,差异均有统计学意义(P0.05)。尿中无机砷、甲基胂酸,二甲基胂酸、总砷与Fas和Bax m RNA表达水平呈正相关(均P0.05),尿砷一级甲基化指数仅与Fas m RNA表达水平呈正相关(P0.05);尿中砷二级甲基化指数与Fas和Bax m RNA表达水平呈负相关(均P0.05)。结论职业性砷暴露工人外周血淋巴细胞中Fas和Bax基因表达升高可能与砷甲基化代谢相关。     

砒霜厂工人砷暴露与六个线粒体基因DNA损伤的关系

目的 探讨职业砷暴露人群六个线粒体基因DNA损伤情况,并分析线粒体DNA损伤与尿砷及其代谢的关系。方法 于2017—2018年,选择云南某高污染砒霜厂78名工人为砷暴露组,选择附近村庄无砷接触史的24名居民为对照组,采用氢化物发生-原子吸收分光光度法测定人群尿中不同形态砷含量,采用实时荧光定量PCR方法检测人群外周血中ND1、ATP6、ATP8、COX1、COX2、COX3等六个线粒体基因DNA损伤水平。结果 砷暴露组尿中无机砷、一甲基胂酸、二甲基胂酸及总砷含量均显著高于对照组（P<0.05）,一甲基胂酸和二甲基胂酸百分比显著高于对照组（P<0.05）,二甲基化指数显著低于对照组（P<0.05）。砷暴露组六个线粒体基因DNA损伤水平显著高于对照组（P<0.05）。六个线粒体基因DNA损伤水平与尿中无机砷、一甲基胂酸、二甲基胂酸、一甲基胂酸百分比呈正相关（P<0.05）,与二甲基胂酸百分比呈负相关（P<0.05）。高二甲基化指数组的六个线粒体基因DNA损伤水平显著低于低二甲基化指数组（P<0.05）。结论 职业砷暴露导致人群线粒体DNA损伤,线粒...     

冶炼厂工人p15基因表达与砷及其代谢产物的关系

为探讨尿砷及其代谢产物对p15基因表达的影响,选取某砷冶炼厂76名一线作业工人为暴露组,非职业环境砷暴露的22名当地居民为对照组,采用原子吸收分光光度法检测尿砷各形态水平,计算一、二级甲基化指数;使用qRT PCR法检测外周血中淋巴细胞p15 mRNA的表达情况。结果显示,砷冶炼厂工人尿中无机砷(iAs)、一甲基胂酸(MMA)、二甲基胂酸(DMA)、总砷水平均高于对照组,二级甲基化指数(SMI)低于对照组,p15 mRNA的相对表达水平高于对照组,差异均有统计学意义(P005);尿中iAs (r=0492)、 MMA(r=0531)、 DMA (r=0526)、总砷(r=0531)、 MMA%(r=0340)与p15基因相对表达呈正相关(P005),p15的表达受SMI的影响且呈负相关(r=-0256),差异具有统计学意义(P005)。说明砷可导致职业接触人群中p15基因的相对表达上调,并且存在一定的剂量关系。     

砷接触工人尿甲基砷酸水平与P53基因损伤的关系

[目的]观察砷职业暴露人群尿甲基砷酸水平与P53基因损伤的关系,深入认识砷的遗传毒性。[方法]选取砒霜厂95名砷接触工人作为暴露组,另选对照组55人,采集外周血和晨尿。用氢化物发生原子吸收分光光度法检测尿中各形态砷化合物和总砷含量,并计算一、二级甲基化指数。实时荧光定量PCR扩增人群外周血淋巴细胞P53基因外显子5和8,通过循环阈值推算损伤后扩增效率,间接计算损伤指数。[结果]暴露组工人尿中无机砷（iAs）、甲基砷酸（MMA）、二甲基砷酸（DMA）均明显高于对照组;暴露组工人二级甲基化指数明显低于对照组;暴露组工人P53基因外显子5和8的损伤指数均明显高于对照组;尿中砷一级甲基化指数与P53基因第5外显子损伤指数存在明显的正相关,尿中砷二级甲基化指数与P53基因第5外显子损伤指数存在明显的负相关。[结论]职业砷暴露工人二级甲基化指数明显增加,体内存在较多甲基砷酸,可能是P53基因外显子5损伤的主要原因。     

砷冶炼厂工人肿瘤相关基因mRNA表达变化

目的探讨砷冶炼厂工人肿瘤相关基因mRNA表达变化规律及影响因素。方法选择在岗砷冶炼工人37名、停止砷冶炼85天的工人43名和对照组51名为研究对象,使用带砷预处理系统的原子吸收分光光度法检测研究对象尿中无机砷、甲基胂酸和二甲基胂酸含量;实时荧光定量聚合酶链式反应(PCR)检测研究对象外周血Lin28、Bax、Bcl-2、Fas基因的mRNA相对表达量。结果尿中无机砷、甲基胂酸和二甲基胂酸浓度分别为:在岗砷冶炼工人(133.97±109.53)、(208.93±171.43)和(820.35±487.39)μg/g肌酐;停止砷冶炼工人(123.31±112.72)、(176.21±157.19)和(467.73±392.17)μg/g肌酐;对照组(1.55±1.49)、(0.10±0.09)和(10.47±7.85)μg/g肌酐。砷接触组工人尿中3种砷化合物浓度均显著高于对照组,正在进行砷冶炼的工人二甲基胂酸浓度显著高于停止砷冶炼工人(P0.05)。研究对象相应外周血Lin28、Bax、Bcl-2、Fas基因的mRNA相对表达量分别为:在岗砷冶炼工人(8.88±2.42)、(6.87±1.10)、(7.24±2.31)和(8.23±2.90);停止砷冶炼工人(6.21±2.94)、(5.81±1.72)、(4.50±1.59)和(6.89±2.35);对照组(5.60±1.43)、(5.56±0.98)、(4.88±1.39)和(6.92±1.87)。在岗砷冶炼工人Lin28、Bax、Bcl-2、Fas基因的mRNA相对表达量均显著高于对照组(P0.05)。结论砷冶炼工人多种肿瘤相关基因mRNA高表达,无机砷甲基化代谢转化在相关mRNA高表达中具有重要作用。     

不同人群GSTO1 mRNA表达及与砷甲基化关系

目的 观察谷胱甘肽-S-转移酶(GSTO1)mRNA在砷中毒患者、病区对照和非病区对照人群中的表达及其与尿砷甲基化水平的关系.方法 选取饮水型砷中毒重度患者、轻度患者、病区对照和非病区对照各6例,采用实时定量RT-PCR技术测定研究对象的淋巴细胞中GSTO1 mRNA表达,采用AFS-9130、SAP-10检测尿无机砷(iAS)、一甲基胂酸(MMA)、二甲基胂酸(DMA)、尿总砷TAs含量.结果 中重度组,轻度组、病区对照组人群iAs,MMA,DMA,TAs一甲基化指数(PMI)均明显高于非病区对照人群(P<0.05);中重度组(P_(50)=1.96),轻度组(P_(50)=1.31)、病区对照组人群(P_(50)=1.23)GSTO1mRNA表达高于非病区对照人群(P_(50)=1.015)(P<0.05);GSTO1 mRNA表达与MMA%(r=0.206,P=0.112)、DMA%(r=0.098,P:0.700),PMI(r=0.127,P=0.615)和SMI(r=0.192,P=0.445)无相关性.结论 GSTO1 mRNA表达与砷甲基化无明显关系,砷中毒引起的损伤可能与砷暴露引起GSTO1mRNA表达增高,并将五价砷化物还原为三价砷化物增多有关.     

三价砷甲基转移酶mRNA相对表达与砷甲基化关系的研究

目的观察三价砷甲基转移酶[As(Ⅲ)MT]mRNA在砷中毒患者、病区对照和非病区对照人群中的表达及其与尿砷甲基化水平的关系。方法选取饮水型砷中毒中重度患者、轻度患者、病区对照和非病区对照各6例,采用实时定量RT-PCR技术测定研究对象的淋巴细胞中三价砷甲基转移酶As(Ⅲ)MTmRNA表达,采用原子荧光AFS-9130、形态分析SAP-10检测尿无机砷(iAs)、一甲基胂酸(MMA)、二甲基胂酸(DMA)、总砷(TAs)含量。按PMI=(MMA+DMA)/TAs,SMI=DMA/(MMA+DMA)分别计算一甲基化指数和二甲基化指数。结果中重度组,轻度组、病区对照组人群iAs、MMA、DMA、Tas、PMI、As(Ⅲ)MTmRNA均显著高于非病区对照人群(P<0.05);As(Ⅲ)MTmRNA分别与MMA%(r=0.485,P=0.041)和PMI(r=0.476,P=0.046)呈显著正相关。结论砷暴露可能促进As(Ⅲ)MTmRNA高表达进而引起PMI水平增高导致MMA产生过多。     

饮水型砷暴露对人群甲基化代谢能力的影响

目的探讨饮水型砷暴露对人群甲基化代谢能力的影响。方法以带有砷化物预处理装置的原子吸收分光光度计测定砷暴露人群及无砷暴露对照人群血、尿中无机砷(iAs)、甲基胂(MMA)、二甲基胂(DMA)含量。以iAs、MMA及DMA的总和表示总胂(tAs)水平;以(MMA+DMA)/tAs及DMA/(MMA+DMA)分别计算一甲基化率(PMI)和二甲基化率(SMI)水平。结果砷暴露人群血中iAs、MMA、DMA、tAs及PMI水平均显著高于相应对照人群的水平,而SMI水平显著低于对照人群。尿中MMA水平分别与血中PMI及SMI水平呈显著正相关(r=0.419,P<0.01)及负相关(r=-0.326,P<0.05)。暴露组和对照组血中各种砷化物水平及甲基化率水平在男女间差异无显著性。结论砷暴露人群与无砷暴露人群相比甲基化率有差异,PMI显著增高,SMI显著降低。人群甲基化率无显著性别差异。     

职业性砷暴露对尿砷及外周血miRNA的影响

目的 探讨职业性砷暴露工人尿中不同化学形态砷含量及甲基化能力与外周血miRNA的关系。方法 采用自身对照，选取某矿山55名工人，问卷收集基本信息；采集研究对象正在接触时与脱离接触3个月后的尿液和外周血，高效液相色谱-电感耦合等离子质谱联用(HPLC-ICP-MS)法检测尿中三价及五价无机砷(inorganic arsenic, iAs³⁺、iAs⁵⁺)、一甲基砷酸(monomethylarsonic acid, MMA)、二甲基砷酸(dimethylarsinic acid, DMA)的含量；以尿中四种形态砷含量总和为总砷(total arsenic, tAs),并以一甲基化率(primary methylated index, PMI)、二甲基化率(secondary methylated index, SMI)为指标，计算甲基化能力；同时，采用实时荧光定量PCR检测外周血miR-155、miR-191、miR-200b相对表达量。结果 正在接触时工人尿中iAs³⁺、MMA、DMA、iAs⁵⁺、t...     

砷冶炼厂工人皮肤损害与尿中砷甲基化产物的关系

目的探讨职业砷接触致皮肤病发生与尿中砷甲基化产物的关系。方法选择偏远山区冶炼厂为研究现场,暴露组为91名工人,对照组58人。监测作业场所工作岗位中砷化合物浓度,进行健康监护体检和尿砷形态分析,计算3种砷化合物百分率及一、二级甲基化指数。结果冶炼厂所有检测岗位砷化合物浓度均超过国家职业卫生标准,91名工人中36人存在明显慢性砷中毒样皮肤损害,尿中3种砷化合物(无机砷、甲基砷酸、二甲基砷酸)浓度(Log10)分别为(2.18±0.40)、(2.26±0.35)和(2.77±0.31)μg/g肌酐,明显示高于接砷但无皮肤损害的工人及对照组工人,差异均有统计学意义,冶炼厂存在皮肤损害的工人尿中甲基砷酸浓度占总砷百分率和二级甲基化指数均明显高于其他工人。结论尿中甲基化产物在冶炼厂工人皮肤损害中具有重要作用,二级甲基化指数与砷致皮肤损害有关。     

砷中毒地区外环境砷暴露水平的研究现状

地方性砷中毒是一种严重危害病区居民健康的地方病.根据砷源不同,分为饮水型职业性砷中毒、燃煤型职业性砷中毒和职业性砷中毒.饮水型地方性砷中毒主要是由于长期暴露于饮用水中的砷而引起的慢性砷中毒.饮水中的砷还可以通过农田灌溉等引起粮食、土壤等砷浓度的升高,间接危害居民健康.在以往的研究中发现,饮水型砷中毒地区饮用水砷超标,不...     

砷冶炼车间砷危害动态观察

长期吸入砷化合物可发生慢性砷中毒,发生早晚及程度与车间空气砷浓度大致呈平行关系。不脱离砷接触时尿砷可作为砷中毒诊断的重要指标,对尿砷超标者行驱砷治疗可降低砷中毒发病率。     

Urinary arsenic species, toenail arsenic, and arsenic intake estimates in a Michigan population with low levels of arsenic in drinking water

The large disparity between arsenic concentrations in drinking water and urine remains unexplained. This study aims to evaluate predictors of urinary arsenic in a population exposed to low concentrations (≤50?μg/l) of arsenic in drinking water. Urine and drinking water samples were collected from a subsample (n=343) of a population enrolled in a bladder cancer case-control study in southeastern Michigan. Total arsenic in water and arsenic species in urine were determined using ICP-MS: arsenobetaine (AsB), arsenite (As[III]), arsenate (As[V]), methylarsenic acid (MMA[V]), and dimethylarsenic acid (DMA[V]). The sum of As[III], As[V], MMA[V], and DMA[V] was denoted as SumAs. Dietary information was obtained through a self-reported food intake questionnaire. Log(10)-transformed drinking water arsenic concentration at home was a significant (P<0.0001) predictor of SumAs (R(2)=0.18). Associations improved (R(2)=0.29, P<0.0001) when individuals with less than 1?μg/l of arsenic in drinking water were removed and further improved when analyses were applied to individuals who consumed amounts of home drinking water above the median volume (R(2)=0.40, P<0.0001). A separate analysis indicated that AsB and DMA[V] were significantly correlated with fish and shellfish consumption, which may suggest that seafood intake influences DMA[V] excretion. The Spearman correlation between arsenic concentration in toenails and SumAs was 0.36 and between arsenic concentration in toenails and arsenic concentration in water was 0.42. Results show that arsenic exposure from drinking water consumption is an important determinant of urinary arsenic concentrations, even in a population exposed to relatively low levels of arsenic in drinking water, and suggest that seafood intake may influence urinary DMA[V] concentrations.     

Acute arsenic intoxication from environmental arsenic exposure

Reports of acute arsenic poisoning arising from environmental exposure are rare. Two cases of acute arsenic intoxication resulting from ingestion of contaminated well water are described. These patients experienced a variety of problems: acute gastrointestinal symptoms, central and peripheral neurotoxicity, bone marrow suppression, hepatic toxicity, and mild mucous membrane and cutaneous changes. Although located adjacent to an abandoned mine, the well water had been tested for microorganisms only and was found to be "safe." Regulations for testing of water from private wells for fitness to drink are frequently nonexistent, or only mandate biologic tests for microorganisms. Well water, particularly in areas near mining activity, should be tested for metals.     

污染区人群砷累积暴露量及与砷中毒的关系砷污染区人群砷累积暴露量的估计

利用人群流行病学调查资料 ,通过估计人群累积呼吸量和大米食用量的方法 ,估算了污染区人群经呼吸和饮食的累积砷暴露量。并对如何评价人群环境污染物暴露水平的方法进行了探讨。不考虑非污染期经呼吸道的砷暴露时 ,所估计的污染区人群最大累积砷暴露量 ,经呼吸道途径 ,女性为 5 91 4mg ,男性为6 12 9mg。消化道途径为 34 88 74mg,合计女性为 40 80 14mg ,男性为 410 1 6 6mg。按污染时间折算成每日暴露量 :女性为 34 9 1μg (天·人 ) ,男性为 35 0 9μg (天·人 ) ,约为调查时所计算日均暴露量的 80 %左右     

Reduction in urinary arsenic levels in response to arsenic mitigation efforts in Araihazar, Bangladesh

BACKGROUND: There is a need to identify and evaluate an effective mitigation program for arsenic exposure from drinking water in Bangladesh. OBJECTIVE: We evaluated the effectiveness of a multifaceted mitigation program to reduce As exposure among 11,746 individuals in a prospective cohort study initiated in 2000 in Araihazar, Bangladesh, by interviewing participants and measuring changes in urinary As levels. METHODS: The interventions included a) person-to-person reporting of well test results and health education; b) well labeling and village-level health education; and c) installations of 50 deep, low-As community wells in villages with the highest As exposure. RESULTS: Two years after these interventions, 58% of the 6,512 participants with unsafe wells (As >/=50 microg) at baseline had responded by switching to other wells. Well labeling and village-level health education was positively related to switching to safe wells (As < 50 mug/L) among participants with unsafe wells [rate ratio (RR) = 1.84; 95% confidence interval (CI), 1.60-2.11] and inversely related to any well switching among those with safe wells (RR = 0.80; 95% CI, 0.66-0.98). The urinary As level in participants who switched to a well identified as safe (< 50 microg As/L) dropped from an average of 375 microg As/g creatinine to 200 microg As/g creatinine, a 46% reduction toward the average urinary As content of 136 microg As/g creatinine for participants that used safe wells throughout. Urinary As reduction was positively related to educational attainment, body mass index, never-smoking, absence of skin lesions, and time since switching (p for trend < 0.05). CONCLUSIONS: Our study shows that testing of wells and informing households of the consequences of As exposure, combined with installation of deep community wells where most needed, can effectively address the continuing public health emergency from arsenic in drinking water in Bangladesh.     

砷暴露人群尿中7-甲基鸟苷与砷的相关性研究

目的探讨广西南丹地区环境砷暴露居民尿7-甲基鸟苷(7-MG)与尿砷的关系。方法于2014年3月应用多阶段分层抽样方法在南丹长老乡抽取122名6~65岁居民,应用电感耦合等离子体质谱法(ICP-MS)检测尿液中的砷含量,用ELISA法测定尿液中7-MG含量。通过广义线性模型分析砷暴露与尿7-MG的关系。结果长老乡儿童尿7-MG水平(G:10.90μg/g cr)高于成人(G:6.82μg/g cr)(P0.05);Spearman相关分析显示成人及儿童尿7-MG水平与土壤砷、饮水砷、蔬菜砷、粮食砷均无统计学关联(P0.05);调整年龄、性别、BMI及吸烟(或被动吸烟)后,广义线性回归分析显示儿童尿7-MG与尿砷呈正向关联(P0.01);成人尿7-MG主要受吸烟和性别影响,与尿砷无统计学关联。结论本次调查的广西南丹长老乡儿童尿7-MG水平可能是砷暴露的一种相对敏感指标。     

Dietary arsenic exposure in bangladesh

BACKGROUND: Millions of people in Bangladesh are at risk of chronic arsenic toxicity from drinking contaminated groundwater, but little is known about diet as an additional source of As exposure. METHODS: We employed a duplicate diet survey to quantify daily As intake in 47 women residing in Pabna, Bangladesh. All samples were analyzed for total As, and a subset of 35 samples were measured for inorganic arsenic (iAs) using inductively coupled plasma mass spectrometry equipped with a dynamic reaction cell. RESULTS: Median daily total As intake was 48 microg As/day [interquartile range (IQR), 33-67) from food and 4 microg As/day (IQR, 2-152) from drinking water. On average, iAs comprised 82% of the total As detected in dietary samples. After adjusting for the estimated inorganic fraction, 34% [95% confidence interval (CI), 21-49%] of all participants exceeded the World Health Organization's provisional tolerable daily intake (PTDI) of 2.1 microg As/kg-day. Two of the 33 women who used a well with < 50 microg As/L exceeded this recommendation. CONCLUSIONS: When drinking water concentrations exceeded the Bangladesh drinking water standard of 50 microg As/L, ingested water was the dominant source of exposure. However, as drinking water As concentrations decrease, the relative contribution of dietary As sources becomes more important to ingested dose. The combined intake from both diet and drinking water can cause some individuals to exceed the PTDI in spite of using a tube well that contains < 50 microg As/L.