Pesticide Exposure And Neurologic Function In Farmworker

摘要 这样的影响可能会降低个人的生活质量，或者是临床可检测到的功能障碍或坦率的神经疾病的前奏。很少有研究调查慢性低剂量暴露的神经学影响。与其他职业群体相比，农场工人很可能高度接触杀虫剂，但他们的健康从未得到充分研究，部分原因是涉及的后勤问题。我们研究了佛罗里达州中部一群农场工人的农药暴露和神经功能障碍，以解决农药神经毒性的科学问题，并调查这一服务不足的群体中农药对健康的影响。 我们进行了一项横断面研究，比较了接触杀虫剂的农场工人和未接触杀虫剂的农场工人。这项研究的参与者来自佛罗里达州中部一个人口稳定的农场工人社区。这个社区的大多数农场工人从事三种农业之一：种植和收获观赏蕨类植物，在苗圃工作，或采摘柑橘类水果。为了进入这个社区，我们与当地的倡导团体佛罗里达州农民工人协会合作。我们将目标人群定义为当地信用社的成员及其配偶；暴露的农场工人和未暴露的控制组都是从这一人群中招募的。我们筛选了80%的选定个体，81%的合格个体参与了这项研究。我们招募了288名从事农场工作至少一个月的人(农场工人)和51名不符合这一标准的对照组。我们的研究在从确定的人群中招募大样本和高响应率方面是独一无二的。 由于杀虫剂可能会影响神经功能的许多方面，我们使用了一系列测试来评估感觉、运动和认知功能。一些测试是在计算机上进行的。所使用的测试相对独立于教育和文化背景。我们在训练有素的人员亲自组织的结构化访谈中收集了关于农场工作、其他就业、人口统计学、生活方式和病史的信息。我们收集并存档了口腔细胞，作为DNA的来源。基因分析将重点放在与农药代谢有关的基因上，如对氧磷酶。 进度： 在分析工作历史与神经行为表现的关系中，我们发现，曾经做过农活的人在四项测试--数字广度、手指敲击、Santa Ana和姿势摆动--上表现不佳，但对其他四项--符号数字潜伏期、振动触觉阈值、视觉对比度敏感度和握力--几乎没有影响。受影响的测试评估认知和精神运动功能。与农场工作的联系在大小上类似于与年龄和性别等个人特征的联系。从事农活的时间越长，表现越差。与蕨类工作的联系比与苗圃或柑橘工作的联系更一致。以前和现在的农场工人都存在与工作经验持续时间有关的缺陷，即使在没有农药中毒历史的情况下，工作表现的下降也与长期接触有关。我们的结论是，长期从事农业工作与认知和精神运动功能的可测量缺陷有关。我们的研究扩展了之前的发现，在一项大规模的基于人群的研究中证明了与农场工作相关的神经缺陷，该研究比较了不同类型农业的工人。这项研究的结果将有助于我们科学地了解农药暴露对神经功能的影响，并解决服务不足的少数群体的健康问题。

Summary Clinical manifestations of neurotoxicity following high level pesticide exposure are well known, but there is growing concern that pesticides may also produce subclinical neurologic deficits, particularly as a delayed consequence of a poisoning episode or in situations of chronic, low-level exposure. Such effects might degrade an individual's quality of life or be a prelude to clinically detectable dysfunction or frank neurologic disease. Few studies have investigated the neurologic effects of chronic low-dose exposure. Farmworkers are likely to be highly exposed to pesticides, compared to other occupational groups, but their health has never been adequately studied, partly because of the logistical problems involved. We studied pesticide exposure and neurologic dysfunction among a group of farmworkers in central Florida in order to address the scientific issue of pesticide neurotoxicity and to investigate health effects of pesticides in this underserved group,. The specific aims of the study were (i) to determine whether chronic occupational exposure to pesticides impairs sensory, motor or cognitive function evaluated using a battery of neurobehavioral tests; and (ii) to determine whether genetic susceptibility alters the effects of pesticides. We conducted a cross-sectional study comparing pesticide-exposed farmworkers to unexposed controls. Participants in the study came from a farmworker community in central Florida with a stable population. Most farmworkers in this community worked in one of three types of agriculture: growing and harvesting ornamental ferns, working in nurseries, or picking citrus fruit. To gain access to the community, we collaborated with the Farmworker Association of Florida, a local advocacy group. We defined our target population to be members of a local credit union and their spouses; both exposed farmworkers and unexposed controls were recruited from this population. We screened 80% of selected individuals, and 81% of those eligible participated in the study. We recruited 288 individuals who had ever done farm work for at least one month (farmworkers) and 51 controls who did not meet this criterion. Our study is unique in recruiting a large sample from a defined population with a high response rate. Since pesticides potentially affect many aspects of neurologic function, we used a battery of tests to evaluate sensory, motor, and cognitive function. Some tests were implemented on a computer. Tests used were relatively independent of education and cultural background. We collected information on history of farm work, other employment, demographics, lifestyle, and medical history in a structured interview administered in person by trained personnel. We collected and archived buccal cells to use as a source of DNA. Genetic analyses will focus on genes involved in pesticide metabolism, such as paraoxonase. Progress: In analyses of the relationship of work history to neurobehavioral performance, we found that ever having done farm work was associated with poor performance on four tests - digit span, finger tapping, Santa Ana, and postural sway - but had little effect on four others - symbol digit latency, vibrotactile threshold, visual contrast sensitivity, and grip strength. The affected tests evaluate cognitive and psychomotor function. Associations with farm work were similar in magnitude to associations with personal characteristics such as age and gender. Longer duration of farm work was associated with worse performance. Associations with fern work were more consistent than associations with nursery or citrus work. Deficits related to the duration of work experience were seen in former as well as current farmworkers, and decreased performance was related to chronic exposure even in the absence of a history of pesticide poisoning. We conclude that long-term experience of farm work is associated with measurable deficits in cognitive and psychomotor function. Our study extends previous findings by demonstrating farm work-related neurologic deficits in a large, population-based study that compared workers in different types of agriculture. The results of this study will contribute to our scientific understanding of the effects of pesticide exposure on neurologic function and also address the health problems of an underserved minority group.