On August 21, 2014, US EPA released the Second Integrated Urban Air Toxics Report to Congress. This is the final of two reports required by the 1990 Clean Air Act (CAA) to inform Congress on the process in reducing public health risks from urban air toxics.

A copy of the complete report is available here.  

Background

The 1990 CAA identifies 187 hazardous air pollutants (HAPs). In addition, section 112(k) required US EPA to address 30 HAPs of concern in urban areas. These HAPs are identified as urban air toxics. A list of the 30 urban air toxics can be found here.

Findings

US EPA reports the following:

• Sixty six percent reduction in benzene from 1994 to 2009

• Fifty eight percent reduction in mercury from anthropogenic (human-caused) sources from 1990 to 2008

• Ninety five percent reduction in dioxin levels from 1987 to 2000.

• Eighty nine percent decrease in lead from 1980 to 2010

• The removal of an estimated 1.5 million tons per year of air toxics like arsenic, benzene, lead and nickel from stationary sources and another 1.5 million tons per year (about 50 percent) of air toxics from mobile sources.

• And approximately 3 million tons of per year of criteria pollutants have been reduced as co-benefits of air toxics reduction

Benzene

Benzene is emitted by both mobile sources (on-road and off-road), major stationary sources (e.g. petroleum refineries) and area sources (gasoline stations). The 66 percent reduction is based on data from 22 urban monitoring sites from 1994 to 2009.

Mercury

Since 1990 to 2008, mercury from anthropogenic (human-caused) sources has decreased 58 percent. In 1990 more than two-thirds of the anthropogenic mercury came from three sources: coal-fired power plants, municipal waste combustors and medical waste incinerators. In the 1990s regulations on municipal waste combustors and medical waste incinerators required a 90 percent reduction in emissions. In 2011, the Mercury and Air Toxics Standards (MATS) was issued to reduce mercury emissions from coal and oil fired power plants. By 2016 mercury emissions from power plants are expected to drop from 27 tons to 7 tons per year.

Dioxin

The urban air toxics program groups dioxins, furans and dioxin-like PCBs in the dioxin category. There are a total of 29 of these compounds. Seven dioxins, ten furans and 12 dioxin-like PCBs are included in the urban air toxics dioxin category. Dioxin levels are down 95 percent from 1987 to 2000 (from 12.8 kg TEQs to 0.07 kg TEQs).  The US EPA has released strict dioxin standards for municipal waste incinerators, medical waste incinerators and other man-made dioxin sources.

Lead

The majority of airborne lead came from the car emissions. The US EPA phased out lead in gasoline from 1973 through 1995. The major of sources lead emissions now are from major stationary sources (e.g., lead smelters) and aircraft with piston engines that use leaded gasoline (typically personal transportation and flight instruction). Since lead is a criteria pollutant, it has a national ambient air quality standard and a separate monitoring network. Since 1980 to 2010, there has been an 89% reduction in lead in the ambient air.

Methods for achieving the reductions

The report identifies National Standards and National, Regional and Community-Based Initiatives in achieving these reductions.

National Standards for stationary sources include 97 MACTS addressing 174 major source categories and 56 GACTS addressing 68 area source categories and accounting for 90 percent of the worst urban HAPs. National Standards for mobile sources (on and off road) include the 2007 Mobile Source Air Toxics rule and the Tier 3 vehicle and fuel standards.

National, Regional and Community-Based Initiatives 

There are a number of national, regional and community-based initiatives identified in the report. One of the national initiatives was the School air Toxics Monitoring Project. This program looked at 65 schools in 22 states. The entire list of schools is available at http://epa.gov/air/sat/schools.html. This chart identifies the school, location, pollutants monitored and if additional monitoring will be undertaken. Seventeen of the schools will undergo continued monitoring either at the school or in the community as a whole.

EPA’s Air Toxics Enforcement Initiative has been in operation since 2004. It has focused on equipment leaks and industrial flares at chemical manufacturing facilities and petroleum refineries. Since 2004, enforcement cases under the program have resulted in 10 million pounds of HAP reduction and an estimated investment of $ 43 million in pollution controls.

Challenges 

The report identified the following challenges:

• Cumulative impacts research – how does exposure to multiple pollutants impact communities.

• Improved emission data – the current reporting systems are not comprehensive.

• Ambient data in more areas and of more pollutants – air toxics emissions and public exposure are highly localized.

• New monitoring technologies that are less costly and can provide information that is more transparent and accessible to communities and businesses

• Better integration of air toxics, pollution prevention and voluntary programs in regulatory and non-regulatory efforts

• Regulatory tools – regulatory efforts should be directed at source categories that pose a significant risk.

This is just a brief overview of the report. Again the entire report is available here.