Reducing greenhouse-gas (GHG) emissions is good for not only the environment, but human health, a new study shows.
According to a team of scientists from Lawrence Berkeley National Laboratory (Berkeley Lab), the National Institute of Environmental Health Sciences (NIEHS), RAND Corp., and the University of Washington, the economic benefit of reduced health impacts from GHG-reduction strategies in the United States will be $6 billion to $14 billion in 2020, depending on how the reductions are accomplished. This equates to a health benefit of $40 to $93 per metric ton of carbon-dioxide (CO2) reduction.
“The importance of this result,” Dev Millstein, Berkeley Lab project scientist, who participated in the research, said, “is that avoiding adverse health impacts from particulate matter can help offset the cost of implementing policies that reduce GHG emissions.”
The team compared 10 strategies, each equal to one “U.S. wedge.” A wedge is a scenario of activities that reduce annual CO2 emissions by 150 million metric tons in 2020 and 750 million metric tons in 2060. Implemented increasingly, the strategies in each wedge provide greater and greater reductions in carbon emissions compared with a business-as-usual approach.
“This paper (“A Wedge-Based Approach to Estimating Health Co-benefits of Climate Change Mitigation Activities in the United States,” published in the November 2014 issue of Climatic Change) provides an alternative approach to comparing different ways to reduce greenhouse gases according to how much they improve health,” John Balbus, MD, NIEHS senior advisor for public health, who co-wrote the paper with Jeffery B. Greenblatt of Berkeley Lab, Ramya Chari of RAND Corp., Millstein, and Kristie L. Ebi of the University of Washington School of Public Health, said. “Decisions about how to address climate change need to be informed by many factors, but we believe this analysis helps advance the thinking on how to bring health considerations into these decisions.”
Strategies considered by the team encompassed efficiency improvements related to light- and heavy-duty vehicles, buildings, and coal power plants; reduction of light-duty-vehicle miles traveled; and substitution of coal electricity with lower-carbon energy sources. Examples of building-efficiency strategies included adding insulation, sealing, and energy-efficient windows; increasing the efficiency of appliances, lighting, and miscellaneous plug-load devices, such as televisions and computers; and more efficient furnaces and water heaters. Coal-power substitutes included natural gas, nuclear, wind, and solar photovoltaic power.
If measures were implemented at an accelerated pace, resulting in annual reductions of 300 million metric tons of CO2, the savings would be $10 billion to $24 billion in 2020. The accelerated case represents a situation in which extremely aggressive policies aimed at reducing GHG emissions were implemented across the United States.
Health benefits primarily would come from reductions in particulate-matter emissions resulting from movement away from the burning of fossil fuels. Particulate matter less than 10 micrometers in size can enter the lungs and bloodstream. Particulate matter less than 2.5 micrometers in size is considered especially dangerous and has been linked in numerous studies to increased respiratory symptoms, such as coughing and difficulty breathing, decreased lung function, premature death in people with pre-existing conditions, heart attacks, and aggravated asthma.
The researchers estimated the extent to which each of the 10 strategies could decrease GHG and particulate-matter emissions each decade through 2060. Well-established health-impact functions used in public-health studies provided the rate of change between reductions in particulate matter less than 2.5 micrometers in size and estimates of the number of health outcomes. Their sources included the U.S. Environmental Protection Agency’s Regulatory Impact Analysis for particulate matter less than 2.5 micrometers in size, as well as Centers for Disease Control and Prevention databases.
“The results of this study provides policy makers with a better understanding of some of the health-related co-benefits of reducing greenhouse-gas emissions, an area that is very rarely mentioned when the costs and benefits of reducing climate-change impacts are discussed,” Greenblatt said. “It provides them with a more complete picture of the true costs and benefits of climate-change-mitigation programs.”