After the meltdown of Pennsylvania’s Three Mile Island nuclear reactor in 1979, regulators proceeded to review safety requirements for nuclear power plants. This led to the temporary shutdown of some older nuclear power plants operated by the Tennessee Valley Authority (TVA) when they failed to meet recently tightened Nuclear Regulatory Commission (NRC) standards.
Edson Severnini, Carnegie Mellon’s assistant professor of economics and public policy, says those closures may have led to lower birth weights among children in the area at the time, due to exposure to pollution from increased reliance on coal-fired power plants. The sudden removal of nuclear power, which emits no greenhouse gases, led to an increase in the amount of power supplied by nearby coal plants, Severnini wrote. That led to an increase in particulate pollution in areas adjacent to coal plants, as measured by the Environmental Protection Agency (EPA) in total particulate matter (TSP).
At the same time, the average birth weight of infants fell by 134 grams.
Birth weight is a strong indicator of a baby’s health, and low birth weight can indicate a host of health problems in the future, including lower IQ and earlier death, particularly from cardiovascular complications. The author admits that the exact biological mechanism by which pollution contributes to low birth weight is still being researched, but other studies have shown a link between the two.
A unique story
Severnini reviewed the 1985 closure of the Browns Ferry nuclear power plant in Alabama, as well as the Sequoyah plant in Tennessee, which was closed from 1985 to 1988. The closure of the two plants coincided with the increased burning of coal at nearby coal-fired power stations – in 1985, TVA noted in its annual report that coal-fired power plants were performing “extraordinary performance” through the closure of the nuclear power plants.
The region also had hydropower in its energy mix at the time, but additional hydropower could not be added during the years studied due to less than average rainfall. Thus, Severnini writes, “the substitution between nuclear power and coal appears to be one-to-one, that is, every megawatt-hour not produced by nuclear power plants due to the shutdown appears to have been generated by coal power plants.”
Accordingly, the level of TSP in the region increased, reversing the downward TSP trends brought about by the implementation of the Clean Air Act of 1970. (Severnini used a Freedom of Information Act request to access historical TSP measurements collected by the Environmental Protection Agency in the region in the 1980s). The author mapped TSP data at the county level and charted the change in power generation at each of the region’s coal power plants.
He also collected birth weight data from the National Center for Health Statistics (NCHS) and found that babies born in regions with the greatest increase in coal burning had lower birth weights than babies born in other nearby areas. Looking at data from 1983 to 1985, before the nuclear power plant closed, also found that the greatest change in birth weight occurred after the closure.
“That said, it appears that babies born in the first quarter after the lockdown have not been affected at all,” Severnini writes. “However, from the second quarter, babies born in areas with greatly increased energy generation and TSP caused by the closure were born with a lower birth weight compared to the control group. In addition, the effect increased with exposure to additional pollution until it leveled off. It was 97g for babies born in the second quarter after the lockdown, 146g in the third quarter and similar size thereafter.”
The results of the paper are consistent with other studies conducted on air pollution and birth weight. Notably, researchers found that in Beijing, babies whose mothers were in their eighth month during the 2008 Olympic and Paralympic Games were, on average, 23 grams heavier than babies born the year before or after. This coincided with a national move to reduce air pollution in preparation for the global games, with the government taking cars off the road, closing factories and “even [banning] spray outside,” said Science news.
Severnini writes that while nuclear disasters are decidedly detrimental to human health, shutting down power plants must be carefully weighed against the cost of whatever replaces energy. After Japan’s Fukushima disaster, many countries moved to shutting down nuclear facilities, but “closing nuclear plants in the US and abroad may not bring as much net profit as the public believes,” Severnini argues.
Yet he admits that the trade-offs we saw in the 1980s are not the same trade-offs that most energy markets experience today. Natural gas power stations burn cleaner and renewable energy, such as wind and solar energy, can be more easily integrated into the electricity grid. In the case of the planned closure of Indian Point in New York, for example, the governor’s office expects renewable energy to replace all or most of the capacity of the 2GW plant by 2021.
Nature Energy2017. DOI: 10.1038/nenergy.2017.51 (About DOIs).