职业性锰暴露对锰冶炼厂男性工人认知能力的影响

[目的]探讨不同职业锰暴露水平对锰冶炼厂工人认知能力的影响及其他可能影响其认知能力的因素.[方法]选择广西某锰冶炼厂240名男性冶炼工人为暴露组,按锰累积暴露指数(CEI)分为高暴露组(CEI≥2.000,86名)和低暴露组(CEI＜ 2.000,154名),以同一地区某糖厂240名男性工人为对照组,调查其一般情况,并采用北京版蒙特利尔认知评估调查问卷对认知能力进行调查. [结果]该厂锰作业男性工人CEI与认知能力呈负相关(r=-0.324,P＜0.05).控制年龄、婚姻状况等协变量后,暴露组工人认知能力低于对照组人群(P＜0.01),且高暴露组工人认知能力低于低暴露组(P＜0.05).多重线性回归分析显示,影响锰暴露工人认知能力的因素有:年龄、文化水平、CEI、吸烟指数(均P＜0.05).[结论]职业性锰暴露可能降低锰冶炼厂男性工人认知能力;此外,年龄、文化水平、吸烟也可影响锰冶炼工人的认知能力.     

锰接触工人神经行为改变与Parkin基因7号外显子多态性的关系

[目的]探讨锰接触工人神经行为改变与Parkin基因7号外显子Gly284Arg多态性的相关性. [方法]选工龄在半年以上的职业性锰暴露工人200名和劳动强度相似,但工作环境不接触锰工人94名,按猛累积暴露指数将其分为高、低猛暴露组和对照组.利用沟槽稳定试验和拼板试验进行神经行为改变检测;利用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法对Parkin基因7号外显子多态性位点进行基因分型. [结果]高暴露组中,Parkin基因7号外显子CC型工人的划痕长度、拼板试验得分均低于GG型和GC型,而碰撞次数高于GG型和GC型,其差别有统计学意义(P＜0.05);低暴露组中,Parkin基因7号外显子CC型工人的划痕长度、拼板试验得分均低于GG型和GC型,其差别有统计学意义(P＜0.05),3个基因型工人碰撞次数间差别无统计学意义(P＞0.05);对照组中,Parkin基因7号外显子3个基因型划痕长度、碰撞次数、拼板试验得分之间差异无统计学意义(P＞0.05). [结论]环境因素和遗传因素共同作用更易导致锰引起神经行为改变;携带Parkin基因7号外显子CC基因型的工人是锰损伤的易感者;Parkin基因7号外显子G951C突变导致Gly284Arg多态性有可能作为检测锰致神经行为改变以及锰中毒风险评估的指标.     

长期职业性锰暴露对工人肺功能的影响

[目的]分析长期职业性锰尘和粉尘暴露对工人肺功能的影响,评价锰尘累积暴露与肺功能的剂量-效应关系. [方法]于2011年对广西某锰冶炼厂280名男性工人进行调查,并回顾性收集历年各车间锰、粉尘浓度监测资料和2006年与2010年工人肺功能检测结果;根据各车间锰、粉尘浓度和接触工龄分别计算出截至2006年与2010年的锰、粉尘累积暴露量.[结果]该厂锰作业工人2010年各项肺功能指标均值均低于2006年检测值,其中用力肺活量(FVC)、第一秒时间肺活量(FEV1)、最高吸气流量(PIF)、75％呼气流速(MEF75)降低明显,差异有统计学意义(P＜0.05);锰作业工人2006年时锰作业工龄平均为(14.27±6.48)年,FVC、FEV1、MEF75与粉尘累积暴露量负相关(P＜0.05),肺功能各指标与锰累积暴露量均无相关关系(P＞0.05); 2010年时锰作业工人工龄平均为(18.05±6.41)年,FVC、FEV1与粉尘累积暴露量负相关,最高呼气流量(PEF)、MEF75、50％呼气流速(MEF5o)与锰累积暴露量负相关(P＜0.05). [结论]职业性锰尘长期累积暴露与肺功能降低有剂量-效应关系.     

接锰工人计算机神经行为测试探讨

目的通过使用中文版计算机神经行为评价系统(NES-C3)项目的测试,探讨锰对职业接触工人神经行为的影响.方法以100名接锰工人和26名非接锰工人为测试对象,然后选取11个行为测试项目进行测试.将接锰工人按累积暴露指数(CEI)大小分为低暴露组(CRI＜5)与高暴露组(CEI≥5),每名工人由专业人员单独测试.结果暴露组工人的行为如情绪、符号译码、视简单反应时、目标追踪得分,与对照组相比已有明显改变(P＜0.05).相关分析发现神经行为功能改变与锰累积暴露剂量之间存在剂量效应关系.结论长期接触锰可引起职业接触工人情感状态、心理运动能力、手眼协调能力的改变.计算机神经行为测试可作为一种检测职业接锰工人神经系统亚临床损害的较理想的方法.     

锰对作业工人血清一氧化氮合酶活力的影响

目的探讨锰对作业工人血清中一氧化氮合酶(NOS)活力的影响.方法以某冶炼厂43名锰作业工人为接触组,另以30名非接锰者为对照组,采用NOS催化L-精氨酸法测定血清NOS活力;血锰测定采用石墨炉原子吸收法,血铜、铁、锌和工作场所空气中锰浓度的测定采用火焰原子吸收法.结果锰接触组NOS活力为(28.09±4.81)×103单位/L,显著低于对照组的(31.04±4.53)×103单位/L(P＜0.05),且接触组血清NOS活力与血锰值有一定的直线相关关系(r=-0.358,P＜0.05);接触组血锰为(1.05±0.87)μmol/L,高于对照组(0.71±0.47)μmol/L(P＜0.01);接触组和对照组血锌分别为(83.59±16.85)和(92.91±21.89)μmol/L,两组差异有显著性(P＜0.05);但两组间血铜和血铁含量差异均无显著性(P＞0.05).结论接触锰可能导致作业工人血锰含量增加,引起血清NOS活力降低;同时还可引起血锌含量下降.     

饮水暴露六价铬对SD大鼠外周血DNA损伤和氧化应激的影响

[目的]研究饮水摄入六价铬对大鼠外周血DNA损伤和血浆氧化应激的影响. [方法]取雌、雄SD大鼠各40只随机分为4组,每组10只,每笼2只,4组分别自由摄入饮用水(对照)及30、100、300 mg/L重铬酸钾(K2Cr207)水溶液4周,每周3次记录每笼饮水量并更换现配的K2Cr207溶液.实验结束时测定体重及心、肝、肾、肺、胃、脾组织重量,计算脏器系数和大鼠平均每日饮水量,并测定外周血DNA损伤及血浆中8-羟基脱氧鸟苷(8-hydroxydeoxyguanosine,8-OHdG)和丙二醛(malondialdehyde,MDA)的含量. [结果]雌鼠300mg/L组的体重增加量低于对照组(P＜0.05);雌鼠300 mg/L组、雄鼠100 mg/L和300 mg/L组的平均每日饮水量均低于对照组(P＜0.05,P＜0.01).300 mg/L组雌、雄大鼠DNA损伤均加重(P＜0.05).雌鼠100mg/L和300mg/L组血浆中8-OHdG含量及雌鼠3个剂量组和雄鼠100、300mg/L组血浆中MDA含量均显著高于对照组(P＜0.05,P＜0.01). [结论]饮水暴露Cr(Ⅵ)可致大鼠外周血DNA损伤加重,并使血浆中8-OHdG和MDA的含量升高.     

职业性接触乙草胺农药对工人心血管及神经系统的影响

[目的]探讨职业性接触乙草胺农药对工人心血管及神经系统的影响,保护工人身体健康。[方法]分别选择某农药厂工龄半年以上的乙草胺生产工人36名为暴露组、厂行政办公区工作人员102名为对照组。对两组环境空气中乙草胺及其相关溶剂如甲苯、二甲苯进行连续3d的监测,同时选择暴露区及对照区各3人进行连续3d的个体采样测定,评价暴露水平;按统一的实施标准对他们的一般情况、心血管系统（血压、心电图）、神经系统进行了健康检查。[结果]暴露组空气中乙草胺浓度明显高于对照组（P﹤0.01）,而甲苯、二甲苯差异无统计学意义（P﹥0.05）,同时个体采样结果显示暴露组乙草胺浓度显著高于对照组（P﹤0.01）;暴露组心电图异常率显著高于对照组（P﹤0.05）。[结论]职业性接触乙草胺农药对工人心血管系统有一定的影响。     

职业性锰暴露对电焊工脂质过氧化的影响研究

[目的]探讨锰暴露对机体脂质过氧化的影响。[方法]2004年,在淮安市选择84名锰焊作业人员,测定作业场所空气锰浓度,检测血清丙二醛(MDA)含量及超氧化物岐化酶(SOD)、谷胱甘肽过氧化物酶(GSHPx)活性,并以84名服务行业人员为对照。[结果]锰暴露组MDA含量高于对照组,血清SOD、GSHPx活性低于对照组(P<0.01);MDA、SOD与作业场所空气锰浓度呈现一定的剂量反应关系。[结论]锰能使机体脂质过氧化增加,抗氧化氧能力下降,MDA、SOD可以作为锰中毒的早期敏感指标。     

口腔脱落细胞微核技术在职业性铅暴露人员中的应用

目的探讨口腔脱落细胞微核技术在探测铅暴露人群遗传损伤中的应用价值。方法选择生产过程中接触不同浓度铅的某铅酸电池厂工人为接触组,按空气中铅浓度高低分为低浓度组(76名男性工人)和中浓度组(89名男性工人),同厂男性管理人员78名为对照组,分别进行口腔黏膜脱落细胞微核和外周血淋巴细胞微核测试。结果 2种浓度的铅暴露组的口腔黏膜脱落细胞微核率[低浓度组:(3.58±2.49)‰;中浓度组:(4.16±2.32)‰]明显高于对照组[(2.85±2.03)‰],两种浓度铅接触组人员的血淋巴细胞微核率[低浓度组:(3.38±2.16)‰;中浓度组:(4.37±2.43)‰]明显高于对照组[(2.17±1.48)‰],差异均有统计学意义(P0.05)。在职业性铅暴露人群中,口腔黏膜脱落细胞微核试验和外周血淋巴细胞微核试验有相关关系(r=0.227～0.361,P0.05)。结论口腔黏膜脱落细胞微核试验可以作为简易的检测手段,用于对铅暴露作业人员遗传损伤的检测的筛查。     

锰对电焊作业工人心血管功能的影响调查

[目的]探讨锰对工人心血管功能的影响,为锰的心血管毒性研究提供人群资料.[方法]2007年9月,对某大型铝厂某公司检修厂低水平锰暴露电焊工的216人检测心电图和血压,并以110名行政工作人员为对照.[结果]舒张压接触组为(64.25±9.32) mmHg,对照组为(71.56±10.41) mmHg(P＜0.01);收缩压接触组为(111±9.01 ) mmHg,对照组为(110±8.92) mmHg(P＞0.05);高血压患病率,接触组为6.12%,对照组为5.24%(P＞0.05).心电图异常率接触组为26.39%,对照组为14.55%(P＜0.05),主要表现为窦性心动过缓.[结论]锰对作业工人的心血管功能有一定影响.     

Cohort study among workers exposed to benzene in China: II. Exposure assessment

This report describes a retrospective exposure assessment method used in a follow-up mortality study of workers exposed to benzene. The approach quantified historical exposure to benzene in a multi-industry, multicenter cohort, involving 672 factories in 12 cities in China. Historical exposure data were collected to obtain exposure information related to 1,427 work units (departments) and 3,179 unique job titles from benzene-producing or -using factories in which written records and other data sources were evaluated. The basic unit for exposure assessment was a factory/work unit/job title combination which was considered separately during each of seven calendar-year time periods between 1949 and 1987 for a total of 18,435 exposure assignments. Historical information collected to estimate exposure included benzene monitoring data; lists of raw materials and factory products, and the percentage of benzene in each; the total amount and dates of use of benzene or benzene-containing materials; use of engineering controls and personal protective equipment; and other available exposure information. Overall, 38% (ranging from 3% for the earliest periods to 67% for the last period) of the estimates were based primarily on benzene monitoring data. In the absence of job-specific benzene monitoring data for a given calendar period, measurement results or exposure estimates for similar jobs and/or other calendar periods were used in conjunction with other exposure information to derive estimates. Estimated exposure levels are presented by industries and occupations. The highest average exposures during 1949–1987 were observed for the rubber and plastic industry (30.7 ppm), and for rubber glue applicators (52.6 ppm).     

Occupational epidemiology in the rubber industry: Implications of exposure variability

The variability of exposure has important implications for the design of occupational epidemiologic studies. To assess the influence of this variability in the rubber industry, the efficiency of different schemes for classification of exposure to particulates, cyclohexane-soluble contaminants, and solvents was assessed. Groupings based on job title, plant, factors affecting exposure, published classifications, and the International Standard Classification of Occupations of the International Labor Organization (ISCO-ILO) were compared. Statistical parameters for contrast in average exposure between groups and precision of average exposure within groups were developed to enable comparison of the efficiency of different classification schemes. Grouping of exposure to particulates and dermal exposure appeared to be less efficient than grouping of exposure to solvents. Grouping of solvent exposure using occupational title groups, existing classification schemes, and schemes based on factors affecting exposure showed comparable high resolution in exposure levels. Even the most detailed grouping schemes based on the combination of plant and occupational title group showed relatively modest resolution in particulate and dermal exposure levels. Groupings based on factors affecting exposure showed similar resolution for these exposures, but had higher precision due to having fewer groups. Application of optimal exposure grouping strategies will benefit new research on cancer among rubber workers. Eventually, this might resolve the situation in which a complete industry was included on the list of proven human carcinogens.     

Fertility and exposure to solvents among families in the Agricultural Health Study

Background

Several studies have reported associations between solvent exposure and reduced female fertility, but the evidence is inconclusive for male fertility.

Objectives

To investigate the impact of solvent exposure on subfertility among families of male licensed pesticide applicators in the Agricultural Health Study cohort.

Methods

The couples enrolled between 1993 and 1997. Cross‐sectional questionnaire information on work tasks was used to assess exposure to solvents. The data were limited to couples (wife aged less than 40 years) with an attempt at pregnancy in the last four years (n = 2112).

Results

Twenty eight per cent of the couples were defined as subfertile (not conceiving a pregnancy after at least 12 months of unprotected intercourse, regardless of whether or not a pregnancy ultimately occurred). Adjusted subfertility odds ratios (OR) for exposure to solvents were calculated with logistic regression. Female (OR 1.42, 95% CI 1.15 to 1.75) and male exposure to solvents (OR 1.21 (95% CI 0.93 to 1.57) for monthly exposure and 1.40 (95% CI 0.97 to 2.03) for daily or weekly exposure) were associated with subfertility. In farming, spouses may share or exchange jobs. To account for potential dual exposure, variables for parental exposure (either parent exposed or both parents exposed) were also defined. Both were strongly associated with subfertility (OR 1.62 (95% CI 1.20 to 2.17) and OR 2.10 (95% CI 1.22 to 3.60), respectively).

Conclusions

Solvents may impair fertility of either gender, though the evidence for female effects is stronger than for male effects.     

Polybrominated diphenyl ethers (flame retardants) in mother-infant pairs in the Southeastern U.S.

Polybrominated diphenyl ethers (PBDEs) are commonly used flame retardants in foams, building material, electronics, and textiles. These chemicals leach into the environment, where they persist, and are found today in virtually every population worldwide. Several studies in recent years have detected the presence of PBDEs in maternal and infant samples. However, few of these studies were conducted in the U.S., and few examined paired or matched mother blood-cord blood samples. We analyzed serum from 10 mother-infant pairs for the presence of PBDEs in a patient population in the Southeastern U.S. Out of 35 measured PBDE congeners, five (BDE-28, -47, -99, -100, and -153) were present, with detection frequencies of 65–100 %. The total PBDE concentrations in maternal and infant sera were highly correlated (r² = 0.710, p = 0.0043). The levels of BDE-47, -99, and -100 and of total PBDEs were higher in the infant cord sera when compared with those in maternal sera (p < 0.017), suggesting that fetuses and neonates might have higher circulating concentrations of these potentially neurotoxic and endocrine disrupting chemicals compared with their mothers. The primary focus henceforward should be whether there are any deleterious effects from exposure to these chemicals on human health.     

Different acute effects of single-axis and multi-axis hand-arm vibration

Under laboratory conditions the effects of single-axis and multi-axis hand-arm vibration exposure on several strain parameters were tested in up to 20 male subjects. As parameters of these acute effects, the biodynamic vibration behavior of the hand-arm system, the electrical activity of the most affected muscle groups, the skin temperature, the vibration sensitivity of the fingertips, and the subjective vibration sensation were measured. When comparing simulated three-axis vibration exposure with single-axis vibration exposure, synergistic effects in the form of an increasing reaction could be found. It could be proven that the vector sum of the frequency-weighted acceleration in the three axes represents the acute effects better than does the weighted acceleration in the main axis alone. This summation has to take into account the relatively lower effects of vibration in the x- or y-direction compared with the z-direction. On the basis of the experimental results a new proposal for frequency weighting of the three different axes and an energetic summation procedure are derived. Application of this knowledge in the International Standard ISO 5349 is proposed.     

简易气体动式染毒装置的研制与应用

目的:根据实验需求,研制一种简易气体动式染毒装置.方法:染毒装置由水箱、配气箱、染毒盒和排气瓶4个部分组成.使用有机玻璃板制作箱体,利用排水法精确配气,利用重力作用和调节阀调节气流大小.结果:该装置设计简单合理,经实际使用,染毒效果良好.结论:该简易气体动式染毒装置成本低廉、制作简单、配气精确,可以重复使用,能够满足动式染毒实验需求.     

Exposure of children to lead and cadmium from a mining area of Brazil

During the past 50 years the Ribeira river valley, in the southern part of the state of S?o Paulo, Brazil, had been under the influence of the full activity of a huge lead refinery and mine working by the side of the river. The plant completely stopped all kinds of industrial activities at the end of 1995, and part of the worker population and their families still remain living nearby in small communities. The objective of the study was to assess the exposure of children to lead and cadmium in these areas, where residual environmental contamination from the past industrial activity still exists. Blood samples of 295 children aged 7 to 14 years, residing in rural and urban areas around the mine and the refinery, were collected. A questionnaire was given to gather information on food habits, leisure activities, father's past employment, current and former residential places, and other variables. Blood lead and cadmium concentrations were analyzed by graphite furnace atomic absorption spectrometry using Zeeman background correction. Cadmium values obtained in this population were mostly below established quantification limits (0.5 microg/dl). The median of blood lead level (BLL) obtained in children living close to the lead refinery was 11.25 microg/dl, and the median in other mining regions far from the refinery was 4.4 microg/dl. Logistic regression analysis was conducted to examine the independent contribution of selected variables in predicting BLL in these children. The following variables showed significant association with high BLL: residential area close to the lead refinery [odds ratio (OR)=10.38 (95% confidence interval (Cl)=4.86-23.25)], former father's occupational lead exposure [OR=4.07 (95% Cl=1.82-9.24)], and male gender [OR=2.60 (95% Cl=1.24-5.62)].     

Cognitive effects of chronic exposure to lead and solvents

BACKGROUND: Occupational exposure to lead and solvents has declined steadily over the past 20 years, however, construction workers continue to be exposed to these neurotoxicants. The purpose of this study was to investigate the cognitive effects of chronic occupational exposure to lead and solvents. METHOD: Based on K-XRF of tibial bone lead and occupational history of solvent exposure, subjects were classified into four exposure groups: lead (N = 40), solvent (N = 39), lead/solvent (N = 45), and control (N = 33). All subjects completed tests to assess concentration, motor skills, memory, and mood. RESULTS: Relative to controls, the lead, solvent, and lead/solvent groups performed significantly more poorly on a test of verbal memory, while the lead and lead/solvent groups were slower than the solvent and control groups on a task of processing speed. Bone lead was a significant predictor of information processing speed and latency of response while solvent exposure was a significant predictor of verbal learning and memory. CONCLUSIONS: Bone lead was associated with slower speed of processing while exposure to lead and/or solvents reduced efficiency of verbal learning.     

Exposure of hairdressers to the main cosmetics used in hairdressing salons in France: A preliminary study

In recent years, more attention has been given to chemical exposure in hairdressers. This increasing interest is largely due to the various respiratory and skin symptoms observed in hairdressers. According to these symptoms, hairdressers are in contact with various sources of exposure. Particularly in France, little information is available to assess professional exposure of hairdressers. In order to gather information to assess exposure in hairdressers, 11 hairdressing salons were visited. All the salons were located in Brest City (France). Preferentially, small hairdressing salons were visited. Observations were performed to obtain salon characteristics and to record workers' practices. Calculations revealed that in the worst-case scenario, dermal professional exposure reaches 14.68 and 13.67 mg/kg/day for hair coloring and highlighting mixtures, respectively. Inhalation exposure represents 14.2 and 18.1 mg/kg/day for hair coloring and highlighting mixtures, respectively. These exposure values represent baseline values for exposure of French hairdressers working in small hairdressing salons.     

Further reduction in lead exposure in women in general populations in Japan in the 1990s, and comparison with levels in east and south-east Asia

Objective: The objective of the study was to elucidate the current level of environmental lead (Pb) exposure of women in general population in Japan, where the use of organic Pb in automobile gasoline was phased out from 1973 to reach a zero level early in the 1980s. Methods: A survey was conducted in 27 sites throughout Japan from 1991 to 1997. Five hundred and eighty-eight non-smoking women from the sites offered 24-h food duplicate, peripheral blood, and spot urine samples. Pb in food duplicates (Pb-F), blood (Pb-B), and urine (Pb-U) were analyzed by inductively-coupled plasma mass spectrometry. The results of Pb-F and Pb-B were compared with observations from a study conducted from 1977 to 1981 on 339 women at the same sites. Log-normal distribution was assumed for the evaluation of the results. Results: Geometric means (GMs) of Pb-F, Pb-B, and Pb-U in the 1991–1997 study were 9.0 μg/day, 20.2 μg/l, and 2.18 μg/g creatinine, respectively. The values for Pb-F and Pb-B were substantially lower than the values (32.8 μg/day for Pb-F and 31.7 μg/l for Pb-B) obtained in the 1977–1981 study, which were already low when compared internationally. Cd-U values in the period from 1991 to 1997 also appeared to be among the lowest in the world. Analysis for time-dependent changes in Pb-U was, however, not possible at the time of this study because no values were available for the period from 1977 to 1981. Conclusions: Substantial reductions from 1977–1981 levels in environmental Pb exposure were observed among the study populations in Japan. Current exposure levels appear to be lower than those in other parts of Asia, the USA, and Europe. Received: 16 March 1999 / Accepted: 27 August 1999