Burnt sugarcane harvesting is associated with rhinitis symptoms and inflammatory markers

Abstract Introduction: Burnt sugarcane harvesting requires intense physical exertion in an environment of high temperature and exposure to particulate matter. Objective: To evaluate the effects of burnt sugarcane harvesting on rhinitis symptoms and inflammatory markers in sugarcane workers. Methods: A total of 32 male sugarcane workers were evaluated with questionnaire for rhinitis symptoms, and for inflammatory markers on peripheral blood and nasal lavage, in the non-harvesting, and 3 and 6 months into the sugarcane harvesting period. Weather data and particulate matter fine concentrations were measured in the same day. Results: The particulate matter concentrations in sugarcane harvesting were 27 (23-33 µg/m3), 112 (96-122 µg/m3), and 63 (17-263 µg/m3); 24 h temperatures were 32.6 (25.4-37.4 ºC), 32.3 (26.7-36.7 ºC) and 29.7 (24.1-34.0 ºC) and relative humidities were 45.4 (35.0-59.7%), 47.9 (39.1-63.0%), and 59.9 (34.7-63.2%) in the non-harvesting period, three and 6 months of the harvesting period. The age was 37.4 ± 10.9 years. The prevalence of rhinitis symptoms was significantly higher at 3 months of the harvesting period (53.4%), compared to non-harvesting period (26.7%; p = 0.039) and at 6 months into the harvesting period (20%; p = 0.006). Concentrations of interleukin 6 (IL-6) in nasal lavage increased after 3 months of the harvesting period compared to the non-harvesting period (p = 0.012). The presence of rhinitis symptoms, after 3 months of the harvesting period, was directly associated with blood eosinophils and inversely associated with neutrophils. Conclusions: After 3 months of work in burnt sugarcane harvesting the prevalence of rhinitis symptoms and IL-6 in nasal lavage increased. Furthermore, eosinophil counts were directly associated with the rhinitis symptoms in the period of higher concentration of particulate matter.

引言：焚烧法收割甘蔗要求作业人员在高温环境中开展高强度体力劳动，同时暴露于颗粒物污染环境。
研究目的：评估焚烧法收割甘蔗对甘蔗作业人员鼻炎症状（rhinitis symptoms）及炎症标志物的影响。
研究方法：共纳入32名男性甘蔗作业人员，分别在非收割季、甘蔗收割季第3个月及第6个月，通过问卷调研其鼻炎症状，并采集外周血（peripheral blood）与鼻腔灌洗液（nasal lavage）检测炎症标志物；同期每日采集气象数据与细颗粒物（particulate matter fine）浓度数据。
研究结果：非收割季、收割季第3个月及第6个月的细颗粒物浓度分别为27（23~33）μg/m³、112（96~122）μg/m³及63（17~263）μg/m³；24小时平均气温分别为32.6（25.4~37.4）℃、32.3（26.7~36.7）℃及29.7（24.1~34.0）℃；相对湿度分别为45.4（35.0~59.7%）、47.9（39.1~63.0%）及59.9（34.7~63.2%）。受试者平均年龄为37.4±10.9岁。收割季第3个月的鼻炎症状患病率（53.4%）显著高于非收割季（26.7%；p=0.039）与收割季第6个月（20%；p=0.006）。与非收割季相比，收割季第3个月时鼻腔灌洗液中的白细胞介素6（interleukin 6, IL-6）浓度显著升高（p=0.012）。收割季第3个月时，鼻炎症状的存在与外周血嗜酸性粒细胞计数呈正相关，与中性粒细胞计数呈负相关。
研究结论：在焚烧法收割甘蔗的作业环境中工作3个月后，作业人员的鼻炎症状患病率与鼻腔灌洗液中的IL-6浓度均有所升高。此外，在细颗粒物浓度较高的收割时段，嗜酸性粒细胞计数与鼻炎症状呈正相关。