PDF(Pubmed)
Abstract：
UNASSIGNED: To assess leukemia risk in occupational populations exposed to low levels of benzene.
UNASSIGNED: Leukemia incidence data from the Chinese Benzene Cohort Study were fitted using the Linearized multistage (LMS) model. Individual benzene exposure levels, urinary S-phenylmercapturic acid (S-PMA) and trans, trans-muconic acid (t, t-MA) were measured among 98 benzene-exposed workers from factories in China. Subjects were categorized into four groups by rounding the quartiles of cumulative benzene concentrations (< 3, 3-5, 5-12, ≥12 mg/m3·year, respectively). The risk of benzene-induced leukemia was assessed using the LMS model, and the results were validated using the EPA model and the Singapore semi-quantitative risk assessment model.
UNASSIGNED: The leukemia risks showed a positive correlation with increasing cumulative concentration in the four exposure groups (excess leukemia risks were 4.34, 4.37, 4.44 and 5.52 × 10-4, respectively; Ptrend < 0.0001) indicated by the LMS model. We also found that the estimated leukemia risk using urinary t, t-MA in the LMS model was more similar to those estimated by airborne benzene compared to S-PMA. The leukemia risk estimated by the LMS model was consistent with both the Singapore semi-quantitative risk assessment model at all concentrations and the EPA model at high concentrations (5-12, ≥12 mg/m3·year), while exceeding the EPA model at low concentrations (< 3 and 3-5 mg/m3·year). However, in all four benzene-exposed groups, the leukemia risks estimated by these three models exceeded the lowest acceptable limit for carcinogenic risk set by the EPA at 1 × 10-6.
UNASSIGNED: This study demonstrates the utility of the LMS model derived from the Chinese benzene cohort in assessing leukemia risk associated with low-level benzene exposure, and suggests that leukemia risk may occur at cumulative concentrations below 3 mg/m3·year.
UNASSIGNED: Leukemia incidence data from the Chinese Benzene Cohort Study were fitted using the Linearized multistage (LMS) model. Individual benzene exposure levels, urinary S-phenylmercapturic acid (S-PMA) and trans, trans-muconic acid (t, t-MA) were measured among 98 benzene-exposed workers from factories in China. Subjects were categorized into four groups by rounding the quartiles of cumulative benzene concentrations (< 3, 3-5, 5-12, ≥12 mg/m3·year, respectively). The risk of benzene-induced leukemia was assessed using the LMS model, and the results were validated using the EPA model and the Singapore semi-quantitative risk assessment model.
UNASSIGNED: The leukemia risks showed a positive correlation with increasing cumulative concentration in the four exposure groups (excess leukemia risks were 4.34, 4.37, 4.44 and 5.52 × 10-4, respectively; Ptrend < 0.0001) indicated by the LMS model. We also found that the estimated leukemia risk using urinary t, t-MA in the LMS model was more similar to those estimated by airborne benzene compared to S-PMA. The leukemia risk estimated by the LMS model was consistent with both the Singapore semi-quantitative risk assessment model at all concentrations and the EPA model at high concentrations (5-12, ≥12 mg/m3·year), while exceeding the EPA model at low concentrations (< 3 and 3-5 mg/m3·year). However, in all four benzene-exposed groups, the leukemia risks estimated by these three models exceeded the lowest acceptable limit for carcinogenic risk set by the EPA at 1 × 10-6.
UNASSIGNED: This study demonstrates the utility of the LMS model derived from the Chinese benzene cohort in assessing leukemia risk associated with low-level benzene exposure, and suggests that leukemia risk may occur at cumulative concentrations below 3 mg/m3·year.
摘要：
■评估暴露于低水平苯的职业人群的白血病风险。
■使用线性化多阶段(LMS)模型拟合来自中国苯队列研究的白血病发病率数据。个别苯暴露水平，尿S-苯基巯基尿酸（S-PMA）和反式，反式粘康酸(t，t-MA)是对来自中国工厂的98名接触苯的工人进行测量的。通过四舍五入累积苯浓度的四分位数（<3、3-5、5-12、≥12mg/m3·年，分别)。使用LMS模型评估苯诱发白血病的风险，并使用EPA模型和新加坡半定量风险评估模型对结果进行了验证。
■LMS模型显示，在四个暴露组中，白血病风险与累积浓度的增加呈正相关（额外的白血病风险分别为4.34、4.37、4.44和5.52×10-4；Ptrend<0.0001）。我们还发现，使用尿t估计的白血病风险，与S-PMA相比，LMS模型中的t-MA与空气中的苯估计的t-MA更相似。LMS模型估计的白血病风险在所有浓度下与新加坡半定量风险评估模型一致，在高浓度下（5-12，≥12mg/m3·年）与EPA模型一致，在低浓度（<3和3-5mg/m3·年）时超过EPA模型。然而,在所有四个苯暴露组中，这三种模型估计的白血病风险超过了EPA设定的致癌风险的最低可接受限值1×10-6.
■这项研究证明了源自中国苯队列的LMS模型在评估与低水平苯暴露相关的白血病风险方面的实用性，并提示在累积浓度低于3mg/m3·年时可能发生白血病风险。
■使用线性化多阶段(LMS)模型拟合来自中国苯队列研究的白血病发病率数据。个别苯暴露水平，尿S-苯基巯基尿酸（S-PMA）和反式，反式粘康酸(t，t-MA)是对来自中国工厂的98名接触苯的工人进行测量的。通过四舍五入累积苯浓度的四分位数（<3、3-5、5-12、≥12mg/m3·年，分别)。使用LMS模型评估苯诱发白血病的风险，并使用EPA模型和新加坡半定量风险评估模型对结果进行了验证。
■LMS模型显示，在四个暴露组中，白血病风险与累积浓度的增加呈正相关（额外的白血病风险分别为4.34、4.37、4.44和5.52×10-4；Ptrend<0.0001）。我们还发现，使用尿t估计的白血病风险，与S-PMA相比，LMS模型中的t-MA与空气中的苯估计的t-MA更相似。LMS模型估计的白血病风险在所有浓度下与新加坡半定量风险评估模型一致，在高浓度下（5-12，≥12mg/m3·年）与EPA模型一致，在低浓度（<3和3-5mg/m3·年）时超过EPA模型。然而,在所有四个苯暴露组中，这三种模型估计的白血病风险超过了EPA设定的致癌风险的最低可接受限值1×10-6.
■这项研究证明了源自中国苯队列的LMS模型在评估与低水平苯暴露相关的白血病风险方面的实用性，并提示在累积浓度低于3mg/m3·年时可能发生白血病风险。
