Even Low Air Pollution Levels Possibly Deadly for Seniors
Marie Donlon | December 29, 2017Despite being considered safe by U.S. government standards, lower levels of air pollution are still likely to prematurely shorten the lives of elderly Americans, according to recent research.
Comparing data about fine particle and ozone pollution levels between 2000 and 2012 with the death rates of approximately 93 percent of Americans covered by Medicare during the period of study, researchers, with the help of computer prediction analysis, estimated that hundreds of American seniors may die prematurely each year thanks to “dirty air.”
"This is the most comprehensive study of short-term exposure to pollution and mortality to date," said senior study author Francesca Dominici, co-director of the Harvard Data Science Initiative in Boston.
"We found that the mortality rate increases almost linearly as air pollution increases. Any level of air pollution, no matter how low, is harmful to human health," Dominici said.
The study is published in the Journal of the American Medical Association.
The discussion of the data seems to contradict the findings reported in the summary:
"...Of all case and control days, 93.6% had PM2.5 levels below 25 μg/m3, during which 95.2% of deaths occurred (21 353 817 of 22 433 862), and 91.1% of days had ozone levels below 60 parts per billion, during which 93.4% of deaths occurred (20 955 387 of 22 433 862). ...:
This means that the 6.4% of days with PM2.5 greater than 25 ug/m3 had only 4.8% of the deaths, and that the 8.9% of days with ozone levels above 60 ppb had only 6.6% of the deaths. This suggests far lower mortality rates for the days with the highest particulate and ozone levels.
4.8%/6.4% = 0.75
Vs
95.2%/93.6% = 1.02
.
6.6%/8.9% = 0.74
Vs
93.4%/91.1% = 1.03
Those are not small differences.