Abstract：
BACKGROUND: Evidence on the public health relevance of exposure to livestock farm emissions is increasing. Research mostly focused on chemical air pollution, less on microbial exposure, while endotoxins are suggested relevant bacterial components in farm emissions. Acute respiratory health effects of short-term exposure to livestock-related air pollution has been shown for NH3 and PM10, but has not yet been studied for endotoxin. We aimed to assess associations between lung function and short-term exposure to livestock farming emitted endotoxin in co-pollutant models with NH3 and PM10.
METHODS: In 2014/2015, spirometry was conducted in 2308 non-farming residents living in a rural area in the Netherlands. Residential exposure to livestock farming emitted endotoxin during the week prior to spirometry was estimated by dispersion modelling. The model was applied to geo-located individual barns within 10 km of each home address using provincial farm data and local hourly meteorological conditions. Regional week-average measured concentrations of NH3 and PM10 were obtained through monitoring stations. Lung function parameters (FEV1, FVC, FEV1/FVC, MMEF) were expressed in %-predicted value based on GLI-2012. Exposure-response analyses were performed by linear regression modelling.
RESULTS: Week-average endotoxin exposure was negatively associated with FVC, independently from regional NH3 and PM10 exposure. A 1.1% decline in FVC was estimated for an increase of endotoxin exposure from 10th to 90th percentile. Stratified analyses showed a larger decline (3.2%) for participants with current asthma and/or COPD. FEV1 was negatively associated with week-average endotoxin exposure, but less consistent after co-pollutant adjustment. FEV1/FVC and MMEF were not associated with week-average endotoxin exposure.
CONCLUSIONS: Lower lung function in non-farming residents was observed in relation to short-term residential exposure to livestock farming emitted endotoxin. This study indicates the probable relevance of exposure to microbial emissions from livestock farms considering public health besides chemical air pollution, necessitating future research incorporating both.
METHODS: In 2014/2015, spirometry was conducted in 2308 non-farming residents living in a rural area in the Netherlands. Residential exposure to livestock farming emitted endotoxin during the week prior to spirometry was estimated by dispersion modelling. The model was applied to geo-located individual barns within 10 km of each home address using provincial farm data and local hourly meteorological conditions. Regional week-average measured concentrations of NH3 and PM10 were obtained through monitoring stations. Lung function parameters (FEV1, FVC, FEV1/FVC, MMEF) were expressed in %-predicted value based on GLI-2012. Exposure-response analyses were performed by linear regression modelling.
RESULTS: Week-average endotoxin exposure was negatively associated with FVC, independently from regional NH3 and PM10 exposure. A 1.1% decline in FVC was estimated for an increase of endotoxin exposure from 10th to 90th percentile. Stratified analyses showed a larger decline (3.2%) for participants with current asthma and/or COPD. FEV1 was negatively associated with week-average endotoxin exposure, but less consistent after co-pollutant adjustment. FEV1/FVC and MMEF were not associated with week-average endotoxin exposure.
CONCLUSIONS: Lower lung function in non-farming residents was observed in relation to short-term residential exposure to livestock farming emitted endotoxin. This study indicates the probable relevance of exposure to microbial emissions from livestock farms considering public health besides chemical air pollution, necessitating future research incorporating both.
摘要：
背景：关于暴露于畜牧业排放的公共卫生相关性的证据正在增加。研究主要集中在化学空气污染上，减少微生物暴露，而内毒素被认为是农场排放物中相关的细菌成分。已显示出NH3和PM10短期暴露于与牲畜有关的空气污染的急性呼吸道健康影响，但尚未对内毒素进行研究。我们旨在评估在NH3和PM10共同污染物模型中，肺功能与短期暴露于畜牧业排放的内毒素之间的关联。
方法：在2014/2015年，对居住在荷兰农村地区的2308名非农业居民进行了肺活量测定。通过色散模型估算了在肺活量测定前一周内居民对畜牧业的暴露量。使用省级农场数据和当地每小时的气象条件，将该模型应用于每个家庭地址10公里内的各个谷仓。通过监测站获得了NH3和PM10的区域周平均测量浓度。肺功能参数（FEV1，FVC，FEV1/FVC,MMEF)以基于GLI-2012的%预测值表示。通过线性回归模型进行暴露响应分析。
结果：每周平均内毒素暴露与FVC呈负相关，独立于区域NH3和PM10暴露。由于内毒素暴露从第10百分位数增加到第90百分位数,FVC估计下降1.1%。分层分析显示，患有当前哮喘和/或COPD的参与者下降幅度更大（3.2%）。FEV1与每周平均内毒素暴露呈负相关，但在共污染物调整后不太一致。FEV1/FVC和MMEF与周均内毒素暴露无关。
结论：观察到非农业居民的肺功能降低与短期居住暴露于畜牧业释放的内毒素有关。这项研究表明，除了化学空气污染外，考虑到公共卫生，牲畜养殖场暴露于微生物排放的可能相关性。需要将两者结合起来的未来研究。
方法：在2014/2015年，对居住在荷兰农村地区的2308名非农业居民进行了肺活量测定。通过色散模型估算了在肺活量测定前一周内居民对畜牧业的暴露量。使用省级农场数据和当地每小时的气象条件，将该模型应用于每个家庭地址10公里内的各个谷仓。通过监测站获得了NH3和PM10的区域周平均测量浓度。肺功能参数（FEV1，FVC，FEV1/FVC,MMEF)以基于GLI-2012的%预测值表示。通过线性回归模型进行暴露响应分析。
结果：每周平均内毒素暴露与FVC呈负相关，独立于区域NH3和PM10暴露。由于内毒素暴露从第10百分位数增加到第90百分位数,FVC估计下降1.1%。分层分析显示，患有当前哮喘和/或COPD的参与者下降幅度更大（3.2%）。FEV1与每周平均内毒素暴露呈负相关，但在共污染物调整后不太一致。FEV1/FVC和MMEF与周均内毒素暴露无关。
结论：观察到非农业居民的肺功能降低与短期居住暴露于畜牧业释放的内毒素有关。这项研究表明，除了化学空气污染外，考虑到公共卫生，牲畜养殖场暴露于微生物排放的可能相关性。需要将两者结合起来的未来研究。
