INITIAL RESPIRATORY RESPONSES WELDING APPRENTICES

尽管研究结果存在一些不一致之处，但有证据表明， 焊接烟雾暴露与职业性哮喘之间的联系已经被 在过去的15年里不断增长。大多数早期的流行病学研究 关于焊接暴露和呼吸影响， 横断面研究设计，选择具有广泛 焊接经验，以及有限的信息的时间和性质， 暴露在焊接烟雾中。我们建议对200名焊接学徒进行研究， 早期测量气道反应性和急性呼吸反应 在学徒的职业生涯中，在他们第一次接触焊接的6个月内。 由于焊工谁经历呼吸问题，由于焊接是少 有可能长期留在焊接领域，学习焊接学徒 刚进入这个领域的人有一个优势， 早期出现呼吸问题。 研究设计重点关注肺功能参数的短期变化 同时进行广泛的暴露评估，包括真实的时间 测量颗粒物和（子样品）NOx。平均水平 将在培训课程期间提供这些变量的暴露， 对于氟化物。最近的证据表明急性呼吸反应15分钟 在第一次每天接触焊接后， 症状将在焊接培训课程开始前进行测量，15 第一次焊接后10分钟，以及整个焊接过程中每小时一次 上网时段真实的个人暴露测量将用于识别 峰值水平和所有措施将有助于测量平均暴露， 上面指定的时间间隔。将检查这些暴露变量 与呼吸反应有关，气道反应性将通过 反应乙酰甲胆碱之前和之后的学徒已经学会了焊接。在 此外，焊接暴露的决定因素将通过考虑 通风、焊接工作类型和工人习惯等因素。 这项研究将提供深入了解的性质之间的关联 焊接暴露和急性呼吸反应。将提出建议 最有效的呼吸和暴露变量， 流行病学评估。对暴露决定因素的评估也将 对考虑暴露控制选项很有用。

Despite some inconsistencies in study results, evidence of an association between welding fume exposure and occupational asthma has been growing over the past 15 years. Most of the earlier epidemiological studies concerning welding exposures and respiratory effects have been limited by their cross-sectional study design, the selection of study populations with extensive welding experience, and limited information on the timing and nature of exposures to welding fumes. We propose a study of 200 welding apprentices in which airway reactivity and acute respiratory responses will be measured early in the apprentices' careers, within 6 months of their first welding exposure. Since welders who experience respiratory problems due to welding are less likely to stay in the welding field long-term, a study of welding apprentices who are just entering the field has the advantage of including workers who experience respiratory problems early on. The study design focuses on short-term changes in pulmonary function parameters with simultaneous extensive exposure assessment that will include real time measurements of particulates, and (on a subsample) NOx. Average levels of exposure during the training session will be provided for these variables and for fluoride. Recent evidence suggests an acute respiratory response 15 minutes after first daily exposure to welding, so pulmonary function and respiratory symptoms will be measured before the start of a welding training session, 15 minutes after the first weld, and at hourly intervals throughout the welding session. The real time personal exposure measurements will be used to identify peak levels and all measures will contribute to measuring average exposures in the specified time intervals above. These exposure variables will be examined in relation to respiratory responses, and airway reactivity will be measured by response to methacholine before and after apprentices have learned to weld. In addition, determinants of welding exposures will be identified by considering factors such as ventilation, type of welding work, and worker habits. This study will provide insights into the nature of the association between welding exposures and acute respiratory responses. Recommendations will be made for the most effective respiratory and exposure variables to use in epidemiological assessments. Assessment of determinants of exposure will also be useful for consideration of exposure control options.