摘要目的 了解职业人群吸入性二氧化钛颗粒的接触水平,探讨其对工人机体氧化应激水平的影响.方法 应用定群设计的研究方法 ,通过问卷调查了解某二氧化钛生产车间成品岗位7名工人的一般信息及职业接触史.观察前后分别采集工人外周静脉血10ml,同时,连续29 d每日班前班后30 min内各采集尿样30 ml(共60 ml),并测定工人每日二氧化钛接触量及车间环境温、湿度.乳胶免疫比浊法测定个体外周血清超敏C反应蛋白(high-sensitivity C-reactive protein,hs-CRP)水平;酶联免疫吸附法(ELISA)测定尿8-羟基脱氧鸟苷(8-hydroxy-deoxyguanosine,8-OHdG)水平.结果 个体每日接触可吸入性二氧化钛颗粒平均浓度为(1. 194±1.015)mg/m3;观察前后血样中hs-CRP水平分别为(1.13±1.08)、(1.33±1.01)mg/L,差异未见统计学意义(t=-0.848,P=0.425);班前班后尿样中8-OHdG水平分别为(3.51±1.39)、(3.65±1.06)μmol/mol Cr.相关性分析显示,随着二氧化钛颗粒接触浓度的增加,8-OHdG水平班前班后差异呈增大趋势(r=0.192,t=2.09,P=0.039).经班次、工龄、年龄、体质指数(BMI)等调整后,单污染物模型分析未发现二氧化钛浓度与班前班后8-OHdG水平差异存在统计学意义(β=0.288,t=1.940,P=0.055).结论 职业场所可吸入二氧化钛颗粒在所研究浓度范围,尚未发现工人机体DNA氧化应激水平发生明显变化.

abstractsObjective To investigate the inhalable titanium dioxide exposure level and make an assessment of its oxidative effect on occupational exposed population. Methods A total of 7 workers occupationally exposing to inhalable titanium dioxide were recruited into the study. The basic information and occupational history were collected by interview, while their blood sample (10 ml for each subject) were collected before and after the investigation, respectively. Pre- and post-work shift urine samples (60 ml for each subject) were collected for 29 days consecutively. The daily personal titanium dioxide exposure level,temperature and relative humidity were detected too. Urinary 8-hydroxy-deoxyguanosine (8-OHdG) and serum high-sensitivity C-reactive protein (hs-CRP) were detected by ELISA and latex immunoturbidimetric assay,respectively. Results The mean concentration of air inhalable titanium dioxide was (1. 194 ±1. 015)mg/m3. Serum hs-CRP level before and after the investigation was (1.13 ± 1.08), (1.33 ±1.01)mg/L,respectively. No statistical significance was observed between hs-CRP level before and after the investigation(t = - 0. 848, P = 0. 425). Pre- and post-work shift urinary 8-OHdG was (3.51 ± 1.39),(3.65 ± 1.06)μmol/mol Cr, respectively. A positive correlation was found between the concentration of inhalable titanium dioxide and the changes of 8-OHdG level (r = 0. 192, t = 2. 09, P = 0. 039). Linear mixed-effect models, adjusted by work shift, years of employment, age, body mass index, smoking status,temperature and relative humidity, showed no significant exposure-respond trend between the inhalable titanium dioxide concentration and 8-OHdG level (β = 0. 288, t = 1. 940, P = 0. 055). Conclusion Our findings do not support the potential link between occupationally exposure to inhalable titanium dioxide and high induction of DNA oxidative stress.