环境保护局上周晚些时候宣布，将结束长达20多年制定监测工厂化农场空气污染方法的努力，实际上关闭了该机构根据《清洁空气法》对这些潜在污染排放设施进行监管的断断续续的尝试。
The Environmental Protection Agency late last week announced it would end a 20-plus-year effort to develop methods to monitor air pollution from factory farms, effectively shuttering the agency’s stop-and-start attempts to regulate the potentially pollutant-spewing facilities under the Clean Air Act.
该宣布是在中期选举前几天发布的，环保局将其描述为农民期盼已久的喘息机会，农民历来是特朗普和共和党的重要选民基础。
The announcement came just days before the midterm elections and was characterized by the agency as a long-awaited reprieve for farmers, a historically important constituency for Trump and the Republican Party.
当成万上万头动物被集中饲养在一处时，其粪便产生的污染会从通风风扇吹出，或从巨大的液态粪污池散发出来。畜禽设施排放细颗粒物、氨气、氮氧化物、二氧化硫和挥发性有机化合物，所有这些都构成了有毒混合物。研究表明，这些养殖场的排放是空气污染的主要原因，每年导致美国近12,700人死亡。
When tens of thousands of animals are packed into one place, pollution from their waste is blown from ventilation fans or emanates from giant lagoons of liquid effluent. Livestock facilities emit fine particulate matter, ammonia, nitrogen oxides, sulfur dioxide, and volatile organic compounds, all contributing to a toxic mix. Research has shown that emissions from these operations are a major cause of air pollution, causing nearly 12,700 deaths in the United States a year.