TOXICITY OF BENZENE AT ENVIRONMENTAL CONCENTRATIONS

这些研究试图调查吸入的血液毒性作用。 在环境环境中遇到的浓度的苯。我们有 有证据表明，C57B1小鼠暴露6个月至10ppm。苯 导致某些红血球前体的数量显著减少 细胞：红系集落形成单位(CFU-E)和晚期 正常爆炸。这些结果反映了红系细胞的破坏。 因为CFU-E是已知的两种红系干细胞之一。 这种干扰似乎是有补偿的，因为外围红色 受影响动物的血细胞计数正常。这些发现可能是 从人类健康的角度来看意义重大，因为暴露在 在认为可接受的职业暴露浓度下进行 对苯的危害和目前苯暴露的健康监测 个体通常只涉及外周血细胞计数的评估。 我们建议使用敏感度来评估低水平的苯暴露 造血细胞分析探讨：1.剂量和剂量的性质 低浓度苯的时间响应。2.前兆是否 低浓度下观察到的细胞毒性预示着更广泛的前景 造血损伤。3.在以下情况下产生的有毒影响的程度 低浓度的苯是可逆的。4.苯是否 如果给造血系统额外的药物，毒性会更严重。 压力。

These studies seek to investigate the hematotoxic effects of inhaled benzene at concentrations encountered in environmental settings. We have evidence that exposure of C57B1 mice for six months to 10 ppm. benzene causes a marked reduction in the numbers of certain erythrocyte precursor cells: the erythroid colony forming unit (CFU-E) and the late normoblasts. These results reflect a disruption in erythroid cell production because the CFU-E is one of the two known erythroid stem cells. There appears to be compensation for this disruption because peripheral red blood counts of the affected animals were normal. These findings may be significant from the standpoint of human health because the exposures were conducted at concentrations considered acceptable for occupational exposure to benzene and because current health monitoring of benzene-exposed individuals usually involves only evaluation of peripheral blood counts. We propose to evaluate low level exposures to benzene using the sensitive hematopoietic cell assays to explore: 1. The nature of the dose and temporal responses at low benzene concentrations. 2. Whether precursor cells toxicity observed at low concentrations foreshawdows more extensive hematopoietic damage. 3. The extent to which the toxic effects produced at low concentrations of benzene are reversible. 4. Whether the benzene toxicity would be more severe if hematopoietic system were given additional stress.