Sweeney B, Bingham R M, Amos R J, Petty A C, Cole P V
Br Med J (Clin Res Ed). 1985 Aug 31;291(6495):567-9. doi: 10.1136/bmj.291.6495.567.
The morphology of the bone marrow of 21 dentists who habitually used nitrous oxide in their surgeries was investigated. Exposure to nitrous oxide was measured with an atmospheric sampling device, and each dentist was invited to fill in a questionnaire giving details of medical history, diet, and intake of alcohol. During the trial a full neurological and haematological investigation was carried out and a bone marrow aspirate was examined both morphologically and by the deoxyuridine suppression test. Mean exposures to nitrous oxide ranged from 159 to 4600 parts per million. In all subjects serum vitamin B12 and folate concentrations were within normal limits. Abnormal results of deoxyuridine suppression tests were obtained in three of the 20 dentists tested; two of these three had abnormal white cells in their peripheral blood films. This study provides direct evidence that occupational exposure to nitrous oxide may cause depression of vitamin B12 activity resulting in measurable changes in bone marrow secondary to impaired synthesis of deoxyribonucleic acid.
对21名在手术中习惯性使用一氧化二氮的牙医的骨髓形态进行了研究。使用大气采样装置测量一氧化二氮的暴露量，并邀请每位牙医填写一份问卷，详细说明病史、饮食和酒精摄入量。在试验期间，进行了全面的神经学和血液学检查，并对骨髓抽吸物进行了形态学检查和脱氧尿苷抑制试验。一氧化二氮的平均暴露量范围为百万分之159至4600。所有受试者的血清维生素B12和叶酸浓度均在正常范围内。在20名接受测试的牙医中，有3人的脱氧尿苷抑制试验结果异常；这三人中有两人的外周血涂片中有异常白细胞。这项研究提供了直接证据，表明职业性接触一氧化二氮可能会导致维生素B12活性降低，从而导致骨髓因脱氧核糖核酸合成受损而发生可测量的变化。
