Soutar A, Harker C, Seaton A, Brooke M, Marr I
Department of Environmental and Occupational Medicine, University Medical School, Foresterhill, Aberdeen.
Thorax. 1994 Apr;49(4):352-6. doi: 10.1136/thx.49.4.352.
There is widespread concern that the cultivation of oilseed rape leads to seasonal epidemics of respiratory symptoms in populations living in the neighbourhood, and it has been suggested that the plant is a potent allergen. A study was therefore undertaken to determine the prevalence of seasonal symptoms in rural populations close to and far from areas of oilseed rape cultivation, and to measure the levels of allergen and other potentially harmful substances released by the crop.
Random samples of 1000 adults from the general practice populations of two villages surrounded by oilseed rape fields, and 1000 adults from one village far from such cultivation, were taken. The subjects completed a previously validated questionnaire on respiratory and other symptoms, including questions on symptom seasonality, occupation, and smoking habits. Pollen and fungal spore counts were made around fields of oilseed rape and in the villages. The chemicals released by oilseed rape were measured in the field.
Overall, 86.8% of the subjects completed the questionnaires and the populations of the two samples were generally comparable. Spring and summer exacerbations of symptoms occurred equally in the two areas in approximately 25% of the population. There were small but significant excesses of cough, wheeze, and headaches in spring in the oilseed rape area (2.3% v 1.1%, 6.8% v 4.6%, and 4.8% v 2.8%, respectively), and cough, wheeze, and itchy skin were more prevalent in smokers. Counts of oilseed rape pollen were generally low except adjacent to fields, and counts of fungal spores were mostly higher in the rape than the non-rape areas. Oilseed rape was shown to give off terpenes and these were detected close to fields.
While it is likely that a proportion of the spring symptoms occurring in people living in close proximity to oilseed rape is caused by the plant, the excess of such symptoms is small. This, together with the low levels of pollen in the area, suggests that allergy to oilseed rape pollen is uncommon. The general prevalence of seasonal symptoms in rural areas is of interest, and a proportion of these cases is likely to be caused by factors other than allergy. Release of chemicals by plants and natural rises in summer ozone levels may be contributors.
人们普遍担心油菜种植会导致周边居民出现季节性呼吸道症状流行，并且有人认为这种植物是一种强效过敏原。因此开展了一项研究，以确定在靠近和远离油菜种植区的农村人口中季节性症状的患病率，并测量该作物释放的过敏原和其他潜在有害物质的水平。
从两个被油菜田环绕的村庄的普通执业人群中随机抽取1000名成年人样本，以及从一个远离此类种植的村庄中抽取1000名成年人样本。受试者完成了一份先前经过验证的关于呼吸道和其他症状的问卷，包括关于症状季节性、职业和吸烟习惯的问题。在油菜田周围和村庄中进行花粉和真菌孢子计数。在田间测量油菜释放的化学物质。
总体而言，86.8%的受试者完成了问卷，两个样本的人群总体上具有可比性。在大约25%的人群中，两个地区的症状在春季和夏季加重情况相同。油菜种植区春季咳嗽、喘息和头痛的发生率略高但有显著差异（分别为2.3%对1.1%、6.8%对4.6%和4.8%对2.8%），并且咳嗽、喘息和皮肤瘙痒在吸烟者中更为普遍。除了靠近田地的地方，油菜花粉计数总体较低，并且油菜种植区的真菌孢子计数大多高于非油菜种植区。油菜被证明会释放萜类化合物，并且在靠近田地的地方检测到了这些物质。
虽然居住在油菜附近的人群中春季出现的一部分症状可能是由这种植物引起的，但此类症状的超额发生率很小。这一点，再加上该地区花粉水平较低，表明对油菜花粉过敏并不常见。农村地区季节性症状的普遍存在令人关注，其中一部分病例可能是由过敏以外的因素引起的。植物释放化学物质以及夏季臭氧水平自然升高可能是促成因素。
