Apostoli P, Alessandro G, Placidi D, Alessio L
Institute of Occupational Health, University of Brescia, Italy.
Int Arch Occup Environ Health. 1998 Oct;71(7):445-52. doi: 10.1007/s004200050304.
To investigate the excretion of styrene metabolites (mandelic acid, MA, and phenylglyoxylic acid, PGA) in workers employed in plastic manufacturing to verify the possible influence of coexposure to acetone on styrene metabolism.
This study was carried out on 50 workers employed in 3 factories producing polyester buttons. The workers were divided into three groups according to three different levels of acetone exposure. The trend of excretion for metabolites was examined during and after work shifts. Styrene and acetone were monitored on Thursday during the entire work shift by passive dosimeters placed on the lapel of the workers' uniforms, desorbed by carbon disulfide, and analyzed by gas chromatography. Biological monitoring was performed by determination of the urinary metabolites of styrene in urine samples collected on Thursday at the middle and the end of the work shift. MA and PGA were determined by a high-pressure liquid chromatographic method.
The styrene concentrations ranged between 16 and 439 mg/m3, and in ten samples they exceeded the TLV-TWA (213 mg/m3). The acetone concentration ranged between 15 and 700 mg/m3 (TLV-TWA 1780 mg/m3), with the mean value being 208 mg/m3. During cleaning operations higher exposures to acetone demonstrated, with concentrations ranging between 500 and 3400 mg/m3. The amounts of MA and PGA determined at the end of workshifts did not significantly differ between the groups with different levels of acetone coexposure. Analysis of variance (ANOVA) between the groups confirmed that MA and PGA excretion did not significantly differ, although the metabolite values measured on the "morning of the day after" appeared higher in those groups with high levels of acetone exposure and were related to the average airborne concentrations of the solvent. In addition, the range and degree of correlation between styrene in air and biological levels of metabolites were modified by coexposure to acetone.
Our data demonstrate that amounts of MA and PGA did not differ in groups with different levels of acetone exposure, but when the acetone air concentration increased the degree of correlation between styrene and MA and PGA decreased. Furthermore, coexposure to acetone levels similar to those described herein may hamper the use of urinary metabolites for the assessment of exposure to styrene, especially on an individual basis.
研究塑料制造业工人中苯乙烯代谢物（扁桃酸、MA，以及苯乙酮酸、PGA）的排泄情况，以验证丙酮共同暴露对苯乙烯代谢可能产生的影响。
本研究对3家生产聚酯纽扣的工厂中的50名工人进行。根据丙酮暴露的3种不同水平将工人分为3组。在轮班期间及轮班后检查代谢物的排泄趋势。周四在整个轮班期间，通过置于工人制服翻领上的被动式剂量计监测苯乙烯和丙酮，用二硫化碳解吸后，采用气相色谱法进行分析。通过测定周四在轮班中期和末期采集的尿液样本中苯乙烯的尿代谢物进行生物监测。MA和PGA采用高压液相色谱法测定。
苯乙烯浓度在16至439毫克/立方米之间，10个样本中的浓度超过了时间加权平均阈限值（213毫克/立方米）。丙酮浓度在15至700毫克/立方米之间（时间加权平均阈限值1780毫克/立方米），平均值为208毫克/立方米。在清洁作业期间，丙酮暴露量更高，浓度在500至3400毫克/立方米之间。不同丙酮共同暴露水平组在轮班结束时测定的MA和PGA量没有显著差异。组间方差分析（ANOVA）证实，MA和PGA排泄没有显著差异，尽管在丙酮暴露水平高的组中，“次日早晨”测得的代谢物值似乎更高，且与溶剂的平均空气浓度有关。此外，丙酮共同暴露改变了空气中苯乙烯与代谢物生物水平之间的相关范围和程度。
我们的数据表明，不同丙酮暴露水平组的MA和PGA量没有差异，但当丙酮空气浓度增加时，苯乙烯与MA和PGA之间的相关程度降低。此外，与本文所述类似水平的丙酮共同暴露可能会妨碍使用尿代谢物评估苯乙烯暴露情况，尤其是在个体层面。
