电焊作业对工人血清一氧化氮合酶活力的影响

目的探讨电焊作业对工人血清中一氧化氮合酶(NOS)活力的影响,进一步了解电焊作业对工人健康损害的机制,为保护电焊作业工人身体健康提供理论依据。方法以某金属结构厂54名电焊作业工人为接触组,不接触毒物的59名非电焊工人为对照组,采用NOS催化L-Arg法测定血清中NOS活力;血锰含量测定采用石墨炉原子吸收法,血中铜、铁、锌、镁、钙含量测定采用火焰原子吸收法。结果接触组工人血清中总NOS活力为(27.88±7.49)U/ml,低于对照组(30.48±4.69)U/ml,差异有显著性(P<0.05),且接触组工人血清中诱导型NOS(iNOS)活力为(16.18±6.70)U/ml,亦低于对照组(19.71±4.26)U/ml,差异有显著性(P<0.05);血锰接触组为(42.73±21.63)μg/L,明显高于对照组(29.97±17.62)μg/L,差异有显著性(P<0.01);血锌接触组和对照组分别为(9.02±3.47)mg/L和(12.72±3.89)mg/L,两组间差异有显著性(P<0.05);接触组和对照组血镁分别为(47.99±9.86)mg/L和(35.82±15.08)mg/L,两组间差异有显著性(P<0.05);两组间血铜、血铁和血钙含量比较,差异均无显著性(P>0.05)。结论电焊作业可能导致工人血锰含量增加,而引起血清NOS活力降低;同时还可使血锌含量下降和血镁含量升高。     

长期接触锰对职业人群血清一氧化氮合酶影响

目的 探讨长期接触锰(Mn)对职业人群血清一氧化氮合酶(NOS)的影响,为保护Mn作业工人健康提供理论依据.方法 选择某局桥梁厂男性电焊工65人作为接触组,另选该厂不接触锰烟尘及其他有害物质的行政、后勤人员65人作为对照组.血Mn水平测定采用石墨炉原子吸收法,血中铜(Cu)、铁(Fe)、锌(Zn)、镁(Mg)、钙(Ca)水平测定采用火焰原子吸收法,血清NOS活力采用NOS催化L-精氨酸法测定.结果 接触组血Mn水平[(1.64±0.18) μmol/L]显著高于对照组[(1.09±0.29) μmol/L],而Ca水平[(0.12±0.04) mmol/L]显著低于对照组[(0.15±0.04) mmol/L],血清NOS活力[(28.47±7.64)×10<'3>U/L]显著低于对照组[(31.12±4.73)×10<'3> U/L],差异均有统计学意义(P <0.05);Cu、Zn和Mg水平差异无统计学意义(P>0.05).结论 长期接触Mn使职工血Mn水平明显升高,Ca水平明显降低,血清NOS活力降低.     

电焊作业对工人血清去甲肾上腺素含量和乙酰胆碱酯酶活性的影响

以某金属结构厂65名电焊作业工人为接触组,另以不接触毒物的49名非电焊工人为对照组,采用酶联免疫吸附法(ELISA)测定血清去甲肾上腺素(NE)含量,用比色法测定血清乙酰胆碱酯酶(AChE)活性。同时检测受试者血锰浓度。结果接触组NE含量为(266.69±211.63)pg/ml,明显高于对照组〔(164.68±130.45)pg/ml〕(P<0.01);接触组AChE活性为(72.35±13.61)U/ml,明显高于对照组〔(60.50±13.00)U/ml〕(P<0.01),接触组血锰为(0.778±0.389)μmol/L,明显高于对照组〔(0.546±0.321)μmol/L〕(P<0.01)。提示电焊作业可导致工人血锰浓度增加,同时引起血清NE含量和AChE活性升高。     

电焊作业对工人血液中必需元素的影响

目的:探讨电焊作业对工人血液中必需元素的影响。方法:以某金属结构厂82名电焊作业工人为接触组,另以不接触毒物的61名非电焊工人为对照组,血锰含量测定采用石墨炉原子吸收法,血中铜、铁、锌、镁、钙含量则采用火焰原子吸收法测定。同时对电焊作业环境空气中的锰浓度、对照组作业场所空气中锰浓度进行采样测定。结果:血锰,接触组为42173±21163μg/L,明显高于对照组(29197±17162μg/L,P<0101);血锌,接触组和对照组分别为9102±3147mg/L和12172±3189mg/L,两者差异有显著性(P<0105);血镁,接触组和对照组分别为47199±9186mg/L和35182±15108mg/L,两者差异有显著性(P<0105);两组间血铜、血铁和血钙含量差异均无显著性(P>0105)。结论:电焊作业可能导致工人血锰含量增加,同时还可引起血锌含量下降,血镁含量升高。     

锰作业工人免疫球蛋白和微量元素含量变化

目的 探讨锰作业工人长期接触锰烟尘对机体免疫功能和微量元素含量的影响变化。方法采用单向免疫扩散法和原子吸收分光光度计分别测定116名锰作业工人血清免疫球蛋白（IgA、IgG、IgM）含量和血中锰、锌、铜、铁和尿锰的含量。结果锰作业工人血清IgG、IgM均低于对照组（P〈0．05）；锰作业工人血清IgM、IgG与血锰含量呈负相关；尿锰与血锰含量呈正相关（P〈0．05），当血锰0．05μmol／L以上时，血锌、铜出现不同程度的下降。血铁含量变化不明显。结论锰作业工人长期接触锰烟尘，能降低机体微量元素锌、铜含量，并对免疫功能存在不同程度的抑制作用。     

铅对接噪工人听力损伤协同作用的观察

目的观察铅对接触噪声工人听力损伤的协同作用及可能机制。方法选择年龄、工龄及接触噪声强度相近的观察组和对照组工人,测定两组工人的单耳单频听阈、血清中超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量,同时测定两组工人血中铅含量,并比较两组数据差异。结果观察组的单耳听阈在4和6 k Hz,明显高于对照组,两者比较,差异有统计学意义(P0.05);观察组和对照组的血中铅浓度分别为(1.9±0.7)和(0.8±0.2)μmol/L,两者比较,差异有统计学意义(P0.01);观察组和对照组的血清中SOD含量分别为(67.2±15.3)和(64.7±13.6)U/ml,两者比较,差异无统计学意义(P0.05);观察组和对照组的血清中MDA含量分别为(7.31±3.36)和(6.53±2.78)μmol/L,两者比较,差异有统计学意义(P0.05)。结论铅对接触噪声工人听力损伤具有协同作用,自由基损害可能是其机制之一。     

钍稀土混合粉尘作业工人血清抗氧化酶活力和丙二醛含量变化

目的 探讨钍稀土混合粉尘对作业工人血清某些抗氧化酶指标和丙二醛(MDA)的影响.方法 采用分光光度法分析血清MDA含量、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活力.结果 接尘组血清MDA含量[(9.74±3.60 )μmol/L]显著高于对照组[(6.90±2.87)μmol/L,P<0.001],抗氧化酶POD[(10.65±5.94)×103 U/L]显著低于对照组[(22.73±11.64) ×103 U/L,P<0.001],SOD和CAT与对照组比较差异无统计学意义.接尘组MDA含量与工龄呈正相关(r=0.248,P=0.038).结论 职业接触钍稀土混合粉尘者血清MDA水平升高,而POD活力下降.     

电焊工人唾液锰和血清锰及尿锰的改变

目的 探讨唾液锰是否可作为锰接触的生物检测指标.方法 选择电焊锰作业工人49名,其中高浓度接触组21人、低浓度接触组28人,采用电感耦合等离子体质谱法(ICP-MS)测定唾液锰和血清锰,用石墨炉原子吸收分光光度法测定尿锰.结果 高浓度接触组的车间空气锰浓度达2.21 mg/m3,低浓度接触组为0.24 mg/m3.接触组的唾液锰和血清锰分别为(4.45±2.17)、(4.64±1.30)μg/L,均明显高于对照组[分别为(3.04±1.40)、(2.70±1.50)μg/L],差异有统计学意义(P＜0.01),尿锰略高于对照组,但差异无统计学意义(P＞0.05).高浓度接触组的唾液锰和血清锰升高者分别为85.71%和100.00%,升高均值为3.04和3.00μg/L;低浓度接触组的唾液锰和血清锰升高者为71.43%和89.29%,升高均值为1.04和1.40 μg/L.唾液锰和血清锰未见伴随工龄的升高趋势.结论 唾液锰与血清锰测定均可反映工人的近期锰接触状况,尿锰的变化不敏感.唾液锰测定方便、准确,可作为新的生物检测指标.     

油泥砂集中流化焚烧处理工艺作业工人的职业健康损害情况

目的 为了早期发现油泥砂集中流化焚烧处理工艺作业工人的早期职业健康损害情况,从而予以有效的干预措施,以降低职业性疾患的发生率.方法 以油泥砂处理厂20名作业人员作为试验组,日常工作不接触或很少接触职业病危害因素的20名其他工作人员作为对照组.采用比色法检测血清中丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)及超氧化物歧化酶(SOD)的活力；采用自动生化分析仪测定血常规；采用石墨炉原子吸收光谱法检测尿总铬含量；采用硝酸酶还原法测定痰液中NO2-/NO3-含量.结果 油泥砂集中流化焚烧项目作业工人尿中总铬含量、血清中MDA含量高于对照组(P＜0.01).SOD活力及痰液中NO2-/NO3-含量分别为(9.83±8.82) mg/g肌酐、(4.46±1.08) nmol/ml、(97.5 ±16.7)U/ml和(60.30±34.51) μmol/L,与对照组的(3.53±1.65)mg/g肌酐、(2.01±0.64) nmol/ml、(110.0±17.4) U/ml、(36.90±21.28) mol/L相比,差异均有统计学意义(P＜0.05和P＜0.01).结论 油泥沙作业工人尿总铬含量、痰液中NO2-/NO3-含量、血清中MDA含量及SOD活力可作为油泥砂集中流化焚烧处理作业工人健康监护的早期指标.     

铅作业工人甲状腺激素水平的研究

目的 探讨铅对作业工人甲状腺激素水平的影响.方法 选择138名铅作业工人及20名教师(对照组)为对象,原子吸收光谱法测定血铅 (PbB)浓度、血液锌原卟啉测定仪测定血锌原卟啉 (ZPP) 浓度,放射免疫分析法检测血清中促甲状腺素(TSH)、游离三碘甲状腺原氨酸 (FT3)、游离四碘甲状腺原氨酸 (FT4) 3项甲状腺功能指标;按GBZ 37-2002<职业性慢性铅中毒诊断标准>分组.结果 接铅组PbB、ZPP含量显著高于对照组,差异均有高度显著性(P＜0.01);接铅组的FT3 (3.18±0.85)pmol/L、FT4 (13.89±4.16) pmol/L,低于对照组的FT3 (5.12±0.94 ) pmol/L(P＜0.01)、FT4 (15.48±2.73) pmol/L(P＜0.05).结论 铅对作业工人甲状腺功能有一定的损害作用,使其分泌甲状腺激素水平降低.     

Past occupational exposure to airborne manganese in a manganese alloy plant

A retrospective exposure assessment of a group of manganese (Mn) alloy workers was performed in conjunction with a 2004 follow-up study, 14 years after cessation of exposure, to evaluate the long-term effects of occupational Mn exposure on neurobehavioral functions. The ferro- and silico-Mn alloy plant opened in 1973 and closed in 1991. The airborne total Mn (TMn) exposures for job groupings were established using personal sampling data from a 1991 industrial hygiene survey. Historical short-term total dust (TDust) data were used to estimate past TDust exposure for job groupings and plant areas. Relationships between Mn content and TDust from the 1991 survey, supported by sparse historical data, were used to estimate TMn content in the historical TDust data. Results showed past personal TDust exposure levels much higher than those found in 1991. Changes in TDust levels and corresponding TMn levels were a function of changes in ventilation, work practices, and operations, not of product (ferro- or silico-Mn). Relationships between TMn and respirable Mn (RMn) from area sampling in 1991 were used to estimate RMn exposure for the job groups. Work histories for 112 workers were developed from payroll records, questionnaires, and interviews and combined with Mn exposure estimates to develop cumulative exposure indices (CEIs). The TMn CEI ranged from 0.27 mg/m(3)x years to 100.24 mg/m(3)x years, with an AM of 24.40 mg/m(3)x years and a GM of 14.06 mg/m(3)x years. The RMn CEI had an AM of 2.95 mg/m(3)x years and a GM of 1.78 mg/m(3)x years with a range of 0.05-12.03 mg/m(3)x years. Overall average TMn exposure intensity, the TMn CEI divided by time worked in years for each worker, had an AM of 1.6 mg Mn/m(3), a GM of 1.0 mg Mn/m(3), range 0.02-6.2 6 mg Mn/m(3). The results of the 2004 follow-up study showed several concentration-response relationships between TMn CEI and neurobehavioral outcomes, which suggest that increase in cumulative TMn exposure level has long-term consequences on the nervous system.     

Metabolic balance of manganese in young men consuming diets containing five levels of dietary manganese

Five healthy men, ages 19-20, were fed a diet for 105 d to measure manganese balance during consumption of conventional foods. The study was divided into five periods of 21, 21, 38, 11 and 14 d, in which the daily dietary intakes of manganese (Mn) were 2.89, 2.06, 1.21, 3.79 and 2.65 mg, respectively. During the last 7 d of each dietary period, subjects resided in a metabolic unit and fasting blood samples were drawn on two mornings. Feces and urine were collected during the last 6 d and integumental losses were collected during the last 60 h of each period. The mean Mn balances for periods 1-5 were -0.083, -0.018, -0.088, +0.657 and +0.136 mg/d, respectively. Corresponding apparent retentions were -2.90, -0.88, -7.40, +17.33 and +5.12%. The mean sum of endogenous and exogenous losses when intake was theoretically zero was calculated to be 392 micrograms/d. When these total losses were combined with the mean positive retention, the theoretical mean dietary level of Mn required for positive balance for these male subjects was 3.5 mg/d or 50 micrograms/kg.     

Comparative evaluation of oxidative stress status and manganese availability in plants growing on manganese mine

This study pioneered an approach that determined the effects of excess manganese (Mn) on three species; Datura stramonium, Alhagi camelthorn and Chenopodium ambrosioides. We investigated their levels of Mn, antioxidative enzymes and oxidative damage biomarkers in plants (zone 1) in and outside (zone 2) the Mn mine. The results showed that total and available Mn were at toxic levels for plants growing on zone 1. The Mn levels in each plant species were higher in leaves, stems and roots. Mn was only accumulated significantly in leaf vacuoles of A. camelthorn. Antioxidative enzyme activities of C. ambrosioides and/or D. stramonium in zone 1 were higher in leaves, stems and then in their roots. Malondialdehyde (MDA) and dityrosine levels were insignificantly higher in tissues of the studied plants in zone 1 with respect to zone 2. The roots of studied plants showed significantly higher levels of these biomarkers in comparison with their leaves in zone 1. Accordingly, antioxidative enzymatic response to Mn-stress in D. stramonium and C. ambrosioides and possibly accumulation of Mn in leaf vacuoles of A. camelthorn, protected them from oxidative damages and involved in their tolerance in Mn mine.