On January 25, 2018, the United States Environmental Protection Agency withdrew a 1995 policy that mandates the use of maximum achievable control technology (MACT) to regulate emissions from major sources of hazardous air pollutants (HAPs), a category of toxic chemicals that may be carcinogenic, mutagenic, or cause other adverse health effects. To better understand the implications and scope of the change in regulatory guidance for HAP emissions of major sources that may reclassify as area sources, the increase in emissions that could legally occur under the new policy is assessed here. Based on facility-level data from a 2014 HAP national emissions inventory, it is estimated that 70% of major sources of HAPs qualify for reclassification as area sources, which could result in a maximum of 35,030 tons per year (tpy) of additional HAP emissions if all sources successfully reclassified. This amount would nearly triple the total volume of HAPs that qualifying major sources emitted in 2014. On average, qualifying sources could emit individually an additional 18.4 tpy. In the 21 states and territories that follow only federal guidelines for controlling HAPs, it is more likely that the estimates presented here could materialize compared to states that have additional guidelines for area sources of HAPs. The quantitative analysis of the potential emission changes resulting from regulatory change is instructive for industry, state and federal decisionmakers, and interested members of the public looking to understand and anticipate how relevant stakeholders will be affected by this policy change.Implications: Withdrawal of a U.S. Environmental Protection Agency policy that mandates the use of maximum achievable control technology (MACT) to regulate emissions from major sources of hazardous air pollutants (HAPs) could result in higher emissions of toxic chemicals that may be carcinogenic, mutagenic, or cause other adverse health effects. Analysis of potential emission changes resulting from regulatory change is instructive for industry, state, and federal decisionmakers, and interested members of the public looking to understand and anticipate how relevant stakeholders will be affected by this policy change.

中文翻译：

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根据2018年《美国清洁空气法》主要来源要求的指南，有害空气污染物的排放影响。

2018年1月25日，美国环境保护署撤回了1995年的一项政策，该政策要求使用最大可达到的控制技术（MACT）来调节来自主要有害空气污染物（HAP）的排放，HAP是一种可能是有毒化学物质。致癌，诱变或引起其他不良健康影响。为了更好地理解针对可能重新分类为面源的主要来源的HAP排放的法规指南变化的含义和范围，在此评估了根据新政策在法律上可能发生的排放增加。根据2014年HAP国家排放清单中的设施级数据，估计70％的主要HAP来源符合重分类为区域来源的条件，最多可能导致35种，如果所有来源均成功重新分类，每年将增加030吨HAP排放。这一数量将使2014年符合主要排放源要求的HAP总量几乎翻三倍。平均而言，符合条件的排放源每年可以单独排放额外的18.4吨。在仅遵循联邦控制HAP准则的21个州和地区中，与针对HAP区域来源有其他准则的州相比，此处提出的估算更有可能实现。法规变化导致的潜在排放变化的定量分析对行业，州和联邦决策者以及希望了解和预期相关利益相关者将如何受到此政策变化影响的感兴趣的公众具有指导意义。启示：退出美国 环境保护署的政策要求使用最大可实现的控制技术（MACT）来控制主要有害空气污染物（HAP）的排放，可能导致更多的有毒化学物质排放，这些化学物质可能会致癌，诱变或对健康产生其他不利影响。由法规变更产生的潜在排放量变化的分析对行业，州和联邦决策者以及希望了解和预测相关利益相关者将如何受到此政策变化影响的公众感兴趣。或造成其他不良健康影响。由法规变更产生的潜在排放量变化的分析对行业，州和联邦决策者以及希望了解和预测相关利益相关者将如何受到此政策变化影响的公众感兴趣。或造成其他不良健康影响。由法规变更产生的潜在排放量变化的分析对行业，州和联邦决策者以及希望了解和预测相关利益相关者将如何受到此政策变化影响的公众感兴趣。