Hines C J, Deddens J A
National Institute for Occupational Safety and Health, 4676 Columbia Parkway, Cincinnati, OH 45226, USA.
Ann Occup Hyg. 2001 Jun;45(4):309-21.
The exposures and work activities of 41 applicators in North Carolina using chlorpyrifos-containing termiticides were characterized. Personal air and urine samples were collected on multiple days within one week. Detailed information about chemical use, tasks, personal protective equipment and hygiene was recorded. During the 202 applicator-days monitored, 415 treatment jobs were performed. Full-shift chlorpyrifos exposures ranged from <0.048 to 110 microg/m(3) (N=184), with a geometric mean (GM) of 10 microg/m(3). Urinary 3,5,6-trichloro-2-pyridinol (TCP) levels ranged from 9.42 to 1960 microg/g creatinine (N=271) and varied significantly by day of the week (GM range: 169-262 microg/g creatinine). Predictive models for chlorpyrifos air exposure and urinary TCP levels were developed using mixed-effects stepwise linear regression. Determinants of airborne chlorpyrifos exposure included minutes chlorpyrifos applied and enclosed crawl space treated (yes/no). Determinants of TCP levels (depending on the model) included day-of-the-week, the chlorpyrifos air concentration one and two days before urine collection, minutes of chlorpyrifos applied one and two days before urine collection, enclosed crawl space treated (yes/no), and commercial structure treated (time-weighted). Within- and between-worker variability was similar for airborne chlorpyrifos; however, for TCP, between-worker variability exceeded within-worker variability by six times. The elimination half-life of TCP (26.9 h) and possibly the short sampling interval (one week) may explain the low TCP within-worker variability. Applicators' weekly mean ln(TCP levels) and weekly mean ln(chlorpyrifos air concentrations) were highly and positively linearly correlated (r(2)=0.73, P<0.0001). In summary, mixed-effects models were successfully constructed to predict airborne chlorpyrifos exposure and urinary TCP levels.
对北卡罗来纳州41名使用含毒死蜱的杀白蚁剂的施药人员的接触情况和工作活动进行了特征描述。在一周内的多个日子采集了个人空气和尿液样本。记录了有关化学品使用、任务、个人防护设备和卫生的详细信息。在监测的202个施药日期间，共进行了415次处理作业。全工作日毒死蜱接触量范围为<0.048至110微克/立方米（N = 184），几何均值（GM）为10微克/立方米。尿中3,5,6 - 三氯 - 2 - 吡啶醇（TCP）水平范围为9.42至1960微克/克肌酐（N = 271），且在一周内各天有显著差异（GM范围：169 - 262微克/克肌酐）。使用混合效应逐步线性回归建立了毒死蜱空气接触量和尿TCP水平的预测模型。空气中毒死蜱接触的决定因素包括施用毒死蜱的分钟数和处理的封闭爬行空间（是/否）。TCP水平的决定因素（取决于模型）包括星期几、尿液采集前一天和两天的毒死蜱空气浓度、尿液采集前一天和两天施用毒死蜱的分钟数、处理的封闭爬行空间（是/否）以及处理的商业建筑（时间加权）。空气中毒死蜱的工人内和工人间变异性相似；然而，对于TCP，工人间变异性比工人内变异性高六倍。TCP的消除半衰期（26.9小时）以及可能较短的采样间隔（一周）可能解释了TCP较低的工人内变异性。施药人员每周平均ln（TCP水平）和每周平均ln（毒死蜱空气浓度）呈高度正线性相关（r² = 0.73，P < 0.0001）。总之，成功构建了混合效应模型以预测空气中毒死蜱接触量和尿TCP水平。
