In the U.S., we use lots of oil and natural gas. Most of our cars are powered using gasoline, which comes from oil, and a large portion of our electricity is generated using natural gas (see more). We have also been getting lots of our oil and natural gas from within our country in recent years (see more, especially slide 15). Using energy from our own country can help make energy cheaper and help insulate energy prices from foreign interruptions. There are concerns, however, that extracting oil and natural gas in the U.S. will lead to residents experiencing worse air quality due to these activities. Poor air quality can make people sick.
What do we know?
Many different research teams have investigated the impact of extracting these natural resources in recent years. There are many different geological (rock) formations under the ground from which oil and natural gas can be extracted. These different formations have different mixtures of oil and gas, and different techniques are used to get the oil and gas to the surface. Due to these differences the emissions can vary across the country (and the world). There are also many different wells in each of these formations, meaning that the emissions of pollutants are spread out over a wide area. This has made it very difficult to get a national picture of how the oil and gas extraction industry impacts human health. A recent study investigated how the oil and gas extraction industry impacts air quality and human health. The authors took data on emissions of pollutants from 2011 for the entire U.S.
What does this mean for pollution and health?
Emissions do not stay at the well site. Once pollution is emitted, it can be carried around by wind and it may react with other chemicals in the air. The air around you is made up of mostly nitrogen and oxygen, but there are other things in it as well. We refer to the fraction of something in the atmosphere as a concentration. For instance, the pie chart shows that the concentration of oxygen is about 22%. This study evaluates the concentration of things in the ‘other’ category. A higher concentration means there is more of that pollutant in the air around you. The researchers used a computer model to determine how the emissions would be moved and transformed in the atmosphere. The researchers were particularly interested in two important pollutants, PM2.5 and ozone (O3). PM2.5, also known as fine particulate matter, is made up of very small particles that can be inhaled and then cause health issues. Ozone causes smog and is a molecule with three oxygen atoms, instead of the usual two. Ozone also causes health issues.
Once the research team calculates the concentrations of these pollutants, they determine the human health burden. This tells them how many people are likely to get certain diseases, and where they are located. The health outcomes they calculate include: premature death, hospital admissions, emergency department visits for asthma, respiratory (breathing system) symptoms, days of work lost, days of school lost, and exacerbated asthma. Poor air quality particularly affects the elderly or very young children, and those with pre-existing conditions. Many people with asthma or heart conditions check the air quality index before deciding if they should go outside.
What did they find?
The researchers predict impacts for 2025 by projecting changes between now and then. This future projection helps policy makers plan for the future. To give you a sense of the values, we will present the base estimates here, but keep in mind that these numbers are not certain. For the year 2025, the researchers estimate 970 ozone-related premature deaths and 1,000 PM2.5-related deaths nationwide. They also estimate that 1,000 people will be admitted to the hospital due to oil and gas activities and that another 3,600 will be admitted to the emergency department. There are likely to be about 100,000 lost work days and over a million cases of asthma and respiratory symptoms. These impacts will not be evenly distributed across the country but will have more impacts near areas of high emissions. On a population-normalized basis, the impacts will be largest in Oklahoma, Louisiana, Colorado, Pennsylvania, and Indiana.
What does that mean?
Although these numbers sound large, these impacts are only a small fraction of national air quality-attributable health impacts. There are hundreds of millions of people in the U.S., and there are many other sources of air pollution. It is important to recognize that this is only one piece of the puzzle. There are air quality standards that require states to ensure that their residents do not experience high levels of pollution. The emissions investigated in this study are not projected to cause pollutant concentrations to exceed these standards. However, even in areas with air quality that meets standards, there are projected to be illnesses. This is because scientists have been unable to find a threshold concentration below which there are no negative health impacts.
This study looked at how extracting oil and gas in the U.S. impacts health. However, importing oil and gas can also have issues. Wells in the U.S. are not the only ones that create pollution. Scientists continue to study lots of different ways to get energy to people, as well as the health impacts of each method. Energy and health are both important, and this study gives us more information to understand how we can meet all of our needs.
Source article: “Assessing Human Health PM2.5 and Ozone Impacts from U.S. Oil and Natural Gas Sector Emissions in 2025” by Neal Fann, Kirk Baker, Elizabeth Chan, Alison Eyth, Alexander macpherson, Elizabeth miller, and Jennifer Snyder
Featured image source: Wikimedia Commons