White M C, Etzel R A, Olson D R, Goldstein I F
Division of Environmental Hazards and Health Effects, Centers for Disease Contro and Prevention, Atlanta, GA, USA.
Am J Epidemiol. 1997 Mar 1;145(5):432-8. doi: 10.1093/oxfordjournals.aje.a009125.
Epidemic asthma occurred in New Orleans, Louisiana, in the 1950s and 1960s, but its causes were never fully understood. Subsequently, similar outbreaks of epidemic asthma in Barcelona, Spain, were shown to be caused by the release of soy dust at the harbor. To investigate whether airborne soy dust may have contributed to epidemic asthma in New Orleans, the authors examined historical data on vessel cargo from the New Orleans harbor together with data on emergency department visits for asthma, for the period from 1957 through 1968. Days on which there were 64 or more visits for asthma were twice as likely to have occurred on days when a vessel carrying soy was at the harbor (odds ratio (OR) = 2.3, 95% confidence interval (CI) 1.5-3.3). The association was stronger when the maximum wind speed was less than 12 miles/hour (19.3 km/hour) (OR = 4.0, 95% CI 2.1-7.7) and strongest when wind speeds were low and the prevailing winds were from the south or southwest, the direction of two grain elevators from the hospital (OR = 6.7, 95% CI 1.5-46.7). Various temporal and climatic factors that had been associated with the occurrence of asthma outbreaks did not appear to be important confounding factors. The association was specific to soy cargo; no association was observed between asthma-epidemic days and the presence of either wheat or corn in vessels at the harbor. The results of this analysis provide further evidence that ambient soy dust is very asthmogenic and that asthma morbidity in a community can be influenced by exposures in the ambient atmosphere.
20世纪50年代和60年代，流行性哮喘在路易斯安那州的新奥尔良爆发，但病因一直未完全明确。随后，西班牙巴塞罗那也出现了类似的流行性哮喘疫情，结果发现是港口大豆粉尘的释放所致。为了调查空气中的大豆粉尘是否可能是新奥尔良流行性哮喘的病因之一，作者研究了1957年至1968年期间新奥尔良港船只货物的历史数据以及哮喘急诊就诊数据。哮喘就诊人数达到64人或更多的日子，在有载运大豆船只停靠港口的日子发生的可能性是其他日子的两倍（优势比（OR）=2.3，95%置信区间（CI）1.5 - 3.3）。当最大风速低于12英里/小时（19.3公里/小时）时，这种关联更强（OR = 4.0，95% CI 2.1 - 7.7）；当风速较低且盛行风来自医院附近两个谷物升降机方向的南方或西南方向时，关联最强（OR = 6.7，95% CI 1.5 - 46.7）。之前与哮喘爆发相关的各种时间和气候因素似乎并非重要的混杂因素。这种关联特定于大豆货物；在港口船只中装有小麦或玉米的情况下，未观察到哮喘流行日与之存在关联。该分析结果进一步证明，环境中的大豆粉尘具有很强的致哮喘性，社区中的哮喘发病率可能会受到环境大气暴露的影响。
