吸烟和年龄对电子垃圾拆解工人尿液中8-羟基脱氧鸟苷的影响

目的 研究吸烟和年龄对电子垃圾拆解工人尿液中8-羟基脱氧鸟苷(8-hydroxy-2'-deoxyguanosine,8-OHdG)的影响.方法 采用固相萃取-高效液相色谱电化学检测器(SPE-HPLC-ECD)方法,检测64名电子垃圾拆解男性工人上班前和下班后尿液中8-OHdG浓度.按照吸烟情况和工人的年龄分别对数据进行统计分析.结果 相对于吸烟者(42名),不吸烟者(22名)尿中8-OHdG浓度明显的增高,上班前,不吸烟组的工人尿液中的8-OHdG浓度为(8.25±4.23)μmol/mol肌酐,吸烟组工人尿液中8-OHdG浓度为(5.44±1.18)μmol/mol肌酐,两者差异无统计学意义(t=-0.81,P=0.42).而在下班后,不吸烟组的工人尿液中的8-OHdG浓度为(43.12±16.19)μmol/mol肌酐,大约是吸烟组工人尿液中8-OHdG浓度[(14.82±2.51)μmol/mol肌酐]的3倍.经过1 d暴露下班后,吸烟和不吸烟工人尿液中的8-OHdG浓度差异具有统计学意义(t=-2.33,P<0.05).按照工人的年龄分组,上班前,19岁～(6名)、20岁～(22名)、30岁～(23名)、40～49岁(11名)组工人尿中8-OHdG浓度分别为(1.86±0.66)、(3.57±0.54)、(8.12±4.10)、(11.39±3.70)μmol/mol肌酐,组间差异没有统计学意义(F=0.98,P=0.41);但经过1 d的暴露,下班后,19岁～、20岁～、30岁～、40～49岁组工人尿中8-OHdG浓度分别为(4.19±2.85)、(19.89±5.26)、(28.89±14.61)、(34.94±12.50)μmol/mol肌酐,组间差异具有统计学意义(F=4.81,P=0.03).结论 吸烟对拆解工人尿中8-OHdG浓度有一定的抑制作用,尿中8-OHdG浓度随年龄增高而增加.     

汕头市郊某地人群体内1-羟基萘、2-羟基萘和1-羟基芘暴露研究

目的 以尿中1-羟基萘(1-OHN)、2-羟基萘(2-OHN)和1-羟基芘(1-OHP)为生物标志物,评价汕头市郊普通人群体内多环芳烃(PAHs)暴露水平,探讨各代谢物间的相关性及吸烟对其浓度的影响.方法 2005年8月选择汕头市郊3个自然村[Y1(n=14)、Y2(n=13)和Y3(n=30)],随机采集尿液,以固相萃取-高效液相串联质谱(LC-MS/MS)分析了尿中1-OHN、2-OHN和1-OHP的水平.结合问卷调查表统计分析吸烟对1-OHN、2-OHN和1-OHP浓度的影响.结果 尿中PAHs浓度水平依次为2-OHN＞1-OHN＞1-OHP.Y1、Y2和Y3的1-OHN的浓度中位数分别为1.42、0.56和2.56 μmol/mol肌酐,2-OHN为5.30、2.79和8.70 μmol/mol肌酐,1-OHP为0.33、0.26和0.76 μmol/mol肌酐.由于吸烟的影响,家庭主妇体内PAH暴露水平显著低于男性,吸烟对3种代谢物均有影响,但对2-OHN的影响尤为明显.2-OHN和总羟基萘(∑OHN)的相关性良好(r=0.978,P＜0.01),且2-OHN/∑OHN与其它职业暴露研究结果 明显不同.结论 汕头该采样点人群体内PAHs暴露水平较高,已达到国外职业暴露水平,环境污染和吸烟是影响研究对象1-OHN、2-OHN和1-OHP浓度升高的主要因素.     

焦炉工人血清谷胱甘肽硫转移酶活力和尿8-羟基脱氧鸟苷水平

目的 探讨血清谷胱甘肽硫转移酶（GST）和尿8-羟基脱氧鸟苷（8-OHdG）作为焦炉工人多环芳烃（PAHs）暴露生物监测标志的可行性.方法 用高效液相色谱-电化学方法和试剂盒分别检测47名男性焦炉工和31名男性对照者尿8-OHdG水平和血清GST活力;尿1-羟基芘（1-OHP）作为PAHs接触的内暴露标志,采用碱水解-高效液相色谱方法分析.结果 焦炉工人尿1-OHP浓度的中位数（P25～P75）为[5.7（1.4～12.0）μmol/mol Cr],血清GST活力为[22.1（14.9～31.2）U/ml],尿8-O-HdG水平为[1.9（1.4～15.4）μmol/mol Cr],均高于对照组工人[3.0（0.5～6.4）μmol/mol Cr、13.1（9.5～16.7）U/ml、1.3（1.0～4.0）μmol/mol Cr],差异均有统计学意义（P＜0.05或P＜0.01）.以吸烟分层,两组工人尿1-OHP浓度和血清GST活力仅在吸烟者中、尿8-OHdG水平仅在非吸烟者中差异有统计学意义（均P＜0.01）.焦炉工人血清GST活力和尿1-OHP浓度呈正相关（rs=0.31,P＜0.01,n=78）.多元Logistic回归分析显示,与对照工人相比,焦炉工人血清GST活力＞16.7 U/ml和尿8-OHdG水平＞1.8 μmol/mol Cr的OR值分别为13.2和4.4;高体重指数是影响尿8-OHdG水平下降的独立因素.结论 焦炉工人血清GST活力增强和氧化性DNA损伤增加,吸烟和职业暴露有交互作用;血清GST有可能作为PAHs暴露评价的生物标志;尿8-OHdG检测有助于焦炉工肺癌危险度评价.     

北京市交警多环芳烃暴露及DNA氧化损伤水平研究

目的 了解北京市交警多环芳烃(PAHs)暴露对体内DNA氧化损伤水平的影响.方法 于2007年6-8月,以某城区41名男性外勤交警和34名男性郊区对照人群作为研究对象,进行问卷调查及环境空气PAHs浓度、内暴露指标尿中1-羟基芘(1-OHP)和DNA氧化损伤标志物尿中8-羟基脱氧鸟苷(8-OHdG)的检测,通过单因素及多元回归分析PAHs内外暴露水平对8-OHdG的影响.结果 交警组工作环境空气中细颗粒物(PM2.5)、苯并(a)芘[B(a)P]、PAHs浓度分别为0.096 mg/m3、3.20 ng/m3、38.32 ng/m3,高于郊区居民组相应值0.045 mg/m3、1.54 ng/m3、25.43ng/m3;交警组和郊区居民组人群尿中1-OHP浓度分别为(0.50±0.38)和(0.34±0.28)μmol/mol Cr(P＜0.05),尿中8-OHdG浓度分别为(13.74±6.30)和(11.61±6.02)ng/mg Cr(P＞0.05).多因素分析发现尿中1-OHP和吸烟是影响8-OHdG水平的重要因素,没有发现年龄、饮酒、锻炼习惯等调查因素对尿8-OHdG浓度的影响.结论 北京市交通污染对交警这一职业人群已产生一定的健康影响,环境空气PAHs暴露和吸烟是影响研究人群DNA氧化损伤水平的重要因素.     

复杂电磁环境工作人员尿中8-羟基脱氧鸟苷和8-羟基鸟苷水平及其影响因素分析

目的 对复杂电磁环境(complex electromagnetic environment, CEE)工作人员的DNA和RNA氧化损伤情况以及其影响因素进行分析，为预防和控制职业病危害提供科学依据。方法 采用方便抽样法选择武汉某芯片厂CEE工作人员(n=133)为暴露组和办公室人员(n=56)为对照组，用稀释法和液相色谱-三重四级杆质谱仪测量氧化应激标志物8-羟基脱氧鸟苷(8-OHdG)和8-羟基鸟苷(8-OHG)在其尿液样本中的浓度。根据问卷调查结果，用logistic回归法分析影响8-OHdG的相关因素。结果 暴露组人员尿中的8-OHdG和8-OHG,经尿比重调整后浓度中位数分别为9.34 ng/ml和17.08 ng/ml。与对照组相比，暴露组8-OHdG浓度高于对照组，且差异有统计学意义(Z=-2.194,P=0.028)。CEE(OR=3.07,95%CI:1.35～7.00)、吸烟(OR=2.62,95%CI:1.13～6.08)和运动(OR=2.5,95%CI:1.04～6.00)为危险因素；女性(OR=0.09,95%CI:0.03～0.28)为保护因素。结论 长期暴...     

焦炉工血清GST活力与尿1-羟基芘和GSTM1、GSTT1基因多态的关系

目的研究血清谷胱甘肽硫转移酶(GST)能否作为焦炉工人多环芳烃的暴露评价指标,同时探讨GSTM1、GSTI1基因多态性与血清GST活力的关系.方法选择某焦化厂39名男性焦炉工人和44名男性对照工人,采用统一的调查表调查一般情况.采集静脉血分析血清GST活力和GSTM1、GSTT1基因型,采集尿样分析尿1-羟基芘(1-OHP)浓度.血清GST活力用试剂盒检测;尿1-羟基芘(1-OHP)浓度作为多环芳烃内暴露剂量,用碱水解-高效液相色谱方法测定;GSTM1和GSTT1基因多态性分析采用PCR方法.结果焦炉工人尿1-OHP浓度(中位数为5.60μmol/mol肌酐)和血清GST活力(中位数25.75 U/ml)分别高于对照组(尿1-OHP浓度:中位数1.32 μmol/mol肌酐,血清GST活力:14.54 U/ml),差异均有统计学意义(均P＜0.001).GSTM1(-/-)和GSTT1(-/-)型工人的血清GST活力分别与GSTM1(-/ , / )和GSTT1(-/ , / )型工人的血清GST活力相比,差异均无统计学意义(均P＞0.05).广义线性回归分析显示,尿1-OHP对血清GST的影响具有统计学意义(P＜0.01).血清GST活力和尿1-OHP浓度存在统计学正相关(r=0.357,P＜0.001,n=83).结论焦炉工人血清GST有可能作为多环芳烃暴露评价的参数;未见GSTM1和GSTT1基因缺失对血清GST活力的影响.     

焦化工人尿中多种多环芳烃单羟基代谢物的调查

目的了解焦化工人多种多环芳烃(PAHs)的内暴露水平。方法于2006年11月采集我国南方某焦化厂工人及对照人群尿样。尿液经过酶解、固相萃取(SPE)富集和净化后,采用高效液相色谱-荧光检测方法检测多环芳烃羟基代谢物(HO-PAHs)。结果在尿样中共检测出8种多环芳烃羟基代谢物。除两组人群4-羟基菲浓度中位数接近外,工人组其余HO-PAHs水平均为对照组1倍以上;其中工人组尿中1-羟基芘(1-OHP)浓度是对照组的7倍。吸烟会对受试人群萘和芴的内暴露水平产生显著影响。工人组尿中1-OHP浓度与2-羟基萘(2-HON)、2-羟基芴(2-HOFlu)、9-羟基菲(9-HOPhe)、ΣHOPhe和ΣHO-PAHs均存在显著的相关性,吸烟和非吸烟工人r值范围分别在0.638~0.998和0.805~0.990之间,但在对照组中,1-OHP与其他尿HO-PAHs的相关性低于工人组,r值在0.436~0.993之间,且1-OHP与2-HON的浓度相关性无统计学意义(r值为0.346)。结论在职业高暴露环境下,1-OHP能很好地指示PAHs内暴露水平;仅用1-OHP并不一定能反映一般人群实际PAHs的暴露水平。     

北京市交警与郊区居民的多环芳烃暴露及影响因素

目的评价北京市交通警察和郊区居民多环芳烃暴露水平,探讨1-羟基芘(1-OHP)作为多环芳烃环境暴露生物标志物的影响因素。方法于2007年6—8月进行调查。以62名交通警察和35名郊区居民为调查对象,连续两天采集调查对象所处环境空气中PM2.5,以超声波萃取-高效液相色谱法分析10种多环芳烃含量,评价研究人群外暴露水平;收集研究人群班后尿,采用高效液相色谱法测定多环芳烃暴露标志物1-OHP的浓度;通过问卷调查收集年龄、吸烟、饮酒、体育锻炼等信息,采用多元回归模型分析调查因素对尿1-OHP浓度影响。结果交警组环境空气中苯并(a)芘、芘、多环芳烃总浓度分别为3.20、6.48、38.32 ng/m3,高于郊区居民组相应值(1.54、4.05、25.43 ng/m3);两组人群尿中1-OHP浓度分别为(0.56±0.48)和(0.37±0.28)μmol/mol肌酐,差别具有统计学意义(P<0.05)。吸烟的郊区居民和吸烟量≥20支/d的交警尿中1-OHP浓度显著高于相应的不吸烟个体。未发现年龄、饮酒、锻炼习惯等调查因素对1-OHP浓度的影响。结论北京市交警和郊区居民具有较高的多环芳烃暴露水平,环境空气暴露和吸烟是影响研究人群尿中1-OHP的主要因素。     

天津市老年人群大气多环芳烃暴露与尿中多环芳烃羟基代谢物的关联研究

目的 同时测定尿中多种羟基多环芳烃(OH-PAHs),以期发现适于联合评价多环芳烃(PAHs)内暴露水平的OH-PAHs.方法 于2011年6月采集112名研究对象24 h的个体颗粒物暴露和晨尿样本,用气相色谱-质谱法检测个体颗粒物样本载带的PAHs及尿样中OH-PAHs.结果 尿样中共检出7种OH-PAHs,其中1-羟基萘(1-OHNap)检出浓度最高[(20.54±28.94) μmol/mol Cr],1-羟基芘(1-OHP)检出浓度最低[(0.73±0.63) μmol/mol Cr].各种OH-PAHs的浓度按照1-OHNap＞9-羟基芴(9-OHFlu) ＞2-羟基萘(2-OHNap)＞3-羟基芴(3-OHFlu)＞2-羟基芴(2-OHFlu)＞6-羟基屈(6-OHChr)＞1-OHP的顺序递减,性别和吸烟对研究对象尿液中OH-PAHs的浓度没有显著影响.总羟基萘(∑OHNap)与1-OHNap具有良好的相关性(r=0.948),总羟基芴(∑OHFlu)与9-OHFlu具有良好的相关性(r=0.975),1-OHNap与颗粒物载带的萘的相关性优于2-OHNap,9-OHFlu与颗粒物载带的芴的相关性优于3-OHFlu和2-OHFlu,∑OHNap、∑OHFlu和6-OHChr与1-OHP的r值分别为0.427、0.543和0.655.结论 仅用1-OHP作为机体PHAs的生物标志物并不能反映人体的内暴露水平,1-OHNap和9-OHFlu对∑OHNap和∑OHFlu暴露水平有较好的预测效果;1-OHNap、9-OHFlu结合1-OHP联合测定可以更为准确和全面地评价PAHs内暴露水平.     

燃煤型砷中毒患者症状分级和尿砷水平与尿中8-羟基脱氧鸟嘌呤核苷水平的相关性研究

目的研究燃煤型砷中毒患者症状分级和尿砷水平与尿中8-羟基脱氧鸟嘌呤核苷(8-OHdG)水平的相关性。方法对贵州省某燃煤型慢性地方性砷中毒病区进行调查,确定砷中毒患者并依据诊断标准进行症状分级(n=21)同时选择非砷暴露对照人群(n=6),测定尿中总砷(tAs)和8-OHdG水平。结果砷中毒患者组尿中tAs及8-OHdG水平均显著高于对照组,且重度患者组尿中tAs及8-OHdG水平均显著高于轻度和中度患者组。尿中8-OHdG水平与tAs水平呈显著正相关(r=0.590,P0.01);与砷中毒症状的轻重程度呈显著正相关(r=0.456,P0.05)。结论高砷暴露可引起尿8-OHdG水平增高,且呈剂量-效应关系;高砷暴露所致的损伤可能与氧化损伤关系密切。     

Urinary 1-hydroxypyrene level relative to vehicle exhaust exposure mediated by metabolic enzyme polymorphisms

Polycyclic aromatic hydrocarbons (PAH) are common air pollutants generated from incomplete combustion. The inhalation of exhaust fumes in urban areas has been suggested to be an additional contributing factor. This study investigated the influence of urban traffic exposure, personal lifestyle factors and metabolic enzyme polymorphisms on the urinary 1-hydroxypyrene (1-OHP) level, approximating exposure to PAH. With consents, 95 male taxi drivers exposed to vehicle exhaust in traffic and 75 male office employees received health interviews and provided urine samples. The results showed taxi drivers had higher urinary 1-OHP than the office employees (mean +/- standard deviation were 0.17 +/- 0.10 vs. 0.10 +/- 0.07 mol/mol creatinine, p<0.001). The average urinary 1-OHP level increased from 0.07 micromol/mol creatinine for non-smoking office employees to 0.17 micromol/mol creatinine for those who smoked more than 20 cigarettes daily. The values for taxi drivers with similar smoking statuses were 0.12 and 0.25 micromol/mol creatinine, respectively. Among non-smokers, taxi drivers still had higher 1-OHP level than office employees (0.12 +/- 0.05 vs. 0.07 +/- 0.03 micromol/mol creatinine). The subjects with the m1/m2 or m2/m2 genotype of CYP1A1 MspI or GSTM1 deficiency had significantly higher urinary 1-OHP levels than those with other CYP1A1 MspI and GSTM1 genotypes. Multivariate logistic regression analysis showed that taxi drivers (adjusted odds ratio (OR)=5.1, 95% confidence interval (CI)=1.1-13.6), smokers (OR=5.5, 95% CI=1.6-18.4) and subjects with the m1/m2 or m2/m2 genotype of CYP1A1 MspI (OR=9.7, 95% CI=2.7-35.0) had elevated urinary 1-OHP (greater than the overall median value, 0.11 micromol/mol creatinine). The results of this study suggest smoking contributes to the elevated urinary 1-OHP levels in taxi drivers in addition to taxi driving, and the excess level contributed from traffic exhaust and smoke was regulated by the CYP1A1 MspI genotype. Traffic exhaust exposure, smoking and CYP1A1 MspI genotype contributed to the variation in levels of urinary 1-OHP excretion.     

Increased urinary excretion of 8-hydroxydeoxyguanosine in engine room personnel exposed to polycyclic aromatic hydrocarbons

Background: Previous investigations indicate that engine room personnel on ships are exposed to polycyclic aromatic hydrocarbons (PAH) from oil and oil products, with dermal uptake as the major route of exposure. Several PAH are known carcinogens and mutagens.

Aims: To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxy-guanosine (8OHdG), in engine room personnel, and to study the association between 8OHdG and 1-hydroxypyrene (1OHP), a biological marker for PAH exposure.

Methods: Urine samples were collected from engine room personnel (n = 36) on 10 Swedish and Norwegian ships and from unexposed controls (n = 34) with similar age and smoking habits. The exposure to oils, engine exhaust, and tobacco smoke 24 hours prior to sampling was estimated from questionnaires. The urinary samples were frozen for later analyses of 8OHdG and 1OHP by high performance liquid chromatography.

Results: Excretion in urine of 8OHdG (adjusted to density 1.022) was similar for controls (mean 18.0 nmol/l, n = 33), and for those who had been in the engine room without skin contact with oils (mean 18.7 nmol/l, n = 15). Engine room personnel who reported skin contact with oil had increased excretion of 8OHdG (mean 23.2 nmol/l, n = 19). The difference between this group and the unexposed controls was significant. The urinary levels of ln 1OHP and ln 8OHdG were significantly correlated, and the association was still highly significant when the effects of smoking and age were accounted for in a multiple regression analysis.

Conclusion: Results indicate that exposure to PAH or possibly other compounds from skin contact with oils in engine rooms may cause oxidative DNA damage.

     

Correlation of Urinary 1-Hydroxypyrene and 2-Naphthol with Total Suspended Particulates in Ambient Air in Municipal Middle-School Students in Korea

The authors investigated Korean municipal middle school students to ascertain whether urinary 1-hydroxypyrene (1-OHP) and 2-naphthol–markers for polycyclic aromatic hydrocarbon (PAH) exposure–reflect PAHs in ambient air. The authors used the β-ray absorption method, which is an index of ambient-air PAH exposure, to collect total suspended participate (TSP) data. The authors measured urinary 1-OHP and 2-naphthol concentrations in 137 nonsmoking students in 4 municipal middle schools within 1 km of ambient air monitoring stations. The median concentrations of urinary 1-OHP and 2-naphthol in the study were 0.09 nmole/mol creatinine and 2.19 μmol/mol creatinine, respectively, and the geometric means were 0.10 nmole/mol creatinine and 2.47 μmol/mol creatinine, respectively. Urinary 1-OHP concentration did not correlate significantly with any TSP index. There were significant correlations between urinary 2-naphthol level and the daily mean TSP level calculated for 2 days before survey, for 1 day before survey, and for the day of survey. These data suggest that urinary 2-naphthol may be a good marker for inhalation exposure to PAHs in ambient air.     

炼焦职业暴露工人与对照人群尿中1-羟基芘水平比较

目的比较焦炉工和非职业暴露人群尿中1-羟基芘的不同水平,并探讨可能的各种影响因素.方法 2002年上半年,以某焦化厂265名炼焦作业工人和226名非职业接触对照人群为调查对象,职业接触组收集工作班末尿,对照组收集晨尿.根据环境中多环芳烃监测和调查表评价外暴露因素和可能的混杂因素,采用高效液相色谱法测定尿中1-羟基芘含量,比较两组人群尿中1-羟基芘的不同水平,并分析外暴露等级、吸烟、饮酒、年龄和体重指数的可能影响.结果尿中1-羟基芘浓度呈炉顶工〉炉侧工〉炉底工〉对照的趋势,几何均数依次为13.49、6.56、1.38和0.35 μmol/mol肌酐,差异有统计学意义;各组人群尿中1-羟基芘浓度超标率分别依次为94.81%、84.73%、35.09%和0.88%,差异有统计学意义.对照人群中≥20支/d吸烟组的尿中1-羟基芘水平明显高于不吸烟组,修正几何均数分别为0.47和0.31 μmol/mol肌酐,差异有统计学意义;对照人群中饮酒组的尿中1-羟基芘水平明显低于不饮酒组,修正几何均数分别为0.33和0.47 μmol/mol肌酐,差异有统计学意义.结论焦炉工尿中1-羟基芘水平较高,以炉侧工和炉顶工最为明显,非职业暴露人群尿中1-羟基芘本底水平与吸烟和饮酒因素有关.     

Urinary 1-hydroxypyrene concentrations in Chinese coke oven workers relative to job category, respirator usage, and cigarette smoking

BACKGROUND: 1-Hydroxypyrene (1-OHP) is a biomarker of recent exposure to polycyclic aromatic hydrocarbons (PAHs). We investigated whether urinary 1-OHP concentrations in Chinese coke oven workers (COWs) are modulated by job category, respirator usage, and cigarette smoking. METHODS: The present cross-sectional study measured urinary 1-OHP concentrations in 197 COWs from Coking plant I and 250 COWs from Coking plant II, as well as 220 unexposed referents from Control plant I and 56 referents from Control plant II. RESULTS: Urinary 1-OHP concentrations (geometric mean, micromol/mol creatinine) were 5.18 and 4.21 in workers from Coking plants I and II, respectively. The highest 1-OHP levels in urine were found among topside workers including lidmen, tar chasers, and whistlers. Benchmen had higher 1-OHP levels than other workers at the sideoven. Above 75% of the COWs exceeded the recommended occupational exposure limit of 2.3 micromol/mol creatinine. Respirator usage and increased body mass index (BMI) slightly reduced 1-OHP levels in COWs (P < 0.1). Cigarette smoking significantly increased urinary 1-OHP levels in unexposed referents (P < 0.005), but had no effect in COWs (P > 0.1). CONCLUSIONS: Chinese COWs, especially topside workers and benchmen, are exposed to high levels of PAHs. Urinary 1-OHP concentrations appear to be modulated by respirator usage and BMI in COWs, as well as by smoking in unexposed referents.     

Effects of the exposure to polycyclic aromatic hydrocarbons or toluene on thiobarbituric acid reactive substance level in elementary school children and the elderly in a rural area]

OBJECTIVES: Polycyclic aromatic hydrocarbons (PAH) and toluene have been reported to induce reactive oxygen species and oxidative stress. This study was performed to investigate the effects of low level exposure to PAHs or toluene on the lipid peroxidation level in elementary school children and the elderly in a rural area. METHODS: Forty seven elementary school children and 40 elderly people who were living in a rural area and not occupationally exposed to PAH or toluene were the subjects of this study. Information about active or passive smoking and diet was obtained using a self-administered questionnaire. The urinary 1-hydroxypyrene (1-OHP), 2-naphthol, hippuric acid and thiobarbituric acid reactive substance (TBARS) concentrations were measured, and these values were corrected with the urinary creatinine concentration. RESULTS: In school children, the geometric means of the urinary 1-OHP, 2-naphthol, hippuric acid and TBARS levels were 0.02 micromol/mol creatinine, 0.47 micromol/mol creatinine, 0.14 g/g creatinine and 0.95 micromol/g creatinine, respectively. Those values for the elderly were 0.07 micromol/mol creatinine, 1.87 micromol/mol creatinine, 0.11 g/g creatinine and 1.18 micro mol/g creatinine, respectively. The mean levels of urinary 1-OHP, 2-naphthol and TBARS were significantly higher in the elderly subjects than in the children. The urinary TBARS level was not correlated with the urinary 1-OHP, 2-naphthol and hippuric acid, but they were correlated with the age of the subjects. CONCLUSIONS: These results suggest that low level inhalation exposure to PAH or toluene does not markedly increase lipid peroxidation, and age is a significant determinant of lipid peroxidation.     

Elevated levels of urinary 8-hydroxy-2 -deoxyguanosine, lymphocytic micronuclei, and serum glutathione S-transferase in workers exposed to coke oven emissions

To investigate associations among occupational exposure to coke oven emissions (COEs), oxidative stress, cytogenotoxic effects, change in the metabolizing enzyme glutathione S-transferase (GST), and internal levels of polycyclic aromatic hydrocarbons (PAHs) in coke oven workers, we recruited 47 male coke oven workers and 31 male control subjects from a coke oven plant in northern China. We measured the levels of 1-hydroxypyrene (1-OHP) and 8-hydroxy-2 -deoxyguanosine (8-OHdG) in urine, micronucleated binucleated cells (BNMNs) in peripheral blood lymphocyte, and GST in serum. Our results showed that the group exposed to COEs had significantly increased levels of 1-OHP [median 5.7; interquartile range (IQR), 1.4-12.0 micromol/mol creatinine] compared with the control group (3; 0.5-6.4 micromol/mol creatinine). In addition, the median levels (IQR) of 8-OHdG, BNMNs, and GST were markedly increased in the exposed [1.9 (1.4-15.4) micromol/mol creatinine; 6 (2-8) per thousand ; 22.1 (14.9-31.2) U/L, respectively] compared with controls [1.3 (1.0-4.0) micromol/mol creatinine, 2 (0-4) per thousand; and 13.1 (9.5-16.7) U/L, respectively]. These results appeared to be modified by smoking. However, multivariate logistic regression analysis revealed that exposure to COEs had the highest odds ratio among variables analyzed and that smoking was not a significant confounder of the levels of studied biomarkers. Overall, the present findings suggest that COE exposure led to increased internal PAH burden, genetic damage, oxidative stress, and GST activity. The consequences of the changes in these biomarkers, such as risk of cancer, warrant further investigations.     

Exposure to benzene and urinary concentrations of 8-hydroxydeoxyguanosine, a biological marker of oxidative damage to DNA.

OBJECTIVES--Benzene is an established animal and human carcinogen. The mechanism of benzene toxicity, particularly its leukaemogenic effect, is not fully understood. The modified base 8-hydroxy-deoxyguanosine (8-OHdG) is a sensitive marker of the DNA damage due to hydroxyl radical attack at the C8 of guanine. This damage, if left unrepaired, has been proposed to contribute to mutagenicity and cancer promotion. We conducted this biomonitoring study with the aim of evaluating the association between excretion of 8-OHdG and level of exposure to benzene and other aromatic compounds among occupationally exposed people. METHODS--A random sample of 65 filling station attendants from Rome, Italy was studied for personal exposure to benzene, toluene, and xylenes, and excretion of 8-OHdG. Information about age, length of employment, smoking habits, and diagnostic exposure to x rays was collected by questionnaire. An average yearly level of exposure to benzene and methylbenzenes was calculated for each filling station attendant on the basis of about seven repeated personal samples collected during one year. A spot sample of 20 ml of urine was collected from each worker. Concentrations of 8-OHdG were determined by high performance liquid chromatography (HPLC) with coupled columns. RESULTS--A mean (SD) concentration of 1.36 (0.49) mumol of 8-OHdG/mol of creatinine was measured. A significant correlation was found between urinary 8-OHdG and exposure to benzene (r = 0.34). In a multiple regression analysis relating the concentration of urinary 8-OHdG with the age, length of employment, smoking, diagnostic exposure to x rays and personal exposure to benzene, an increase of 0.15 mumol/mol creatinine in urinary 8-OHdG/unit increase in the natural logarithm of the average yearly benzene concentration was estimated. CONCLUSION--This study shows a dose-response effect between personal exposure to benzene and urinary 8-OHdG concentration; further studies are needed to clarify the biological significance of 8-OHdG as a marker of cancer risk.