Asthma and Coal-Fired Power Plants -- Is there a connection?

As the concern of Americans about claims of catastrophic man-made global warming has diminished, the Progressive Elitists and their EPA have ramped up a campaign against coal-fired power plants based on those plants causing asthma.  The ads put particular emphasis on them causing asthma in children.  Obama even recently claimed that one of his daughters has asthma because of coal-fired power plants and other use of fossil fuels.  Does this viewpoint have an anchor in science and known data?  Let us examine this issue, because surely none of us want children to suffer because coal-fired power plants provide us with inexpensive and reliable electric power.  It may well make sense to use more expensive power, whether natural gas or better scrubbed coal-fired power plants if the coal-fired power plants are truly implicated as the cause of asthma.

In examining this, I am going to use information from a slide presentation on the prevalence of asthma in the US by the Center for Disease Control and Prevention (CDC).  It is found at the bottom of the page here.

Now, it might be that emissions from coal-fired power plants are the exception and this is a known cause.  Let us see if that would be consistent with other data of the CDC.

This graph shows increasing asthma from 1980 to 1996 and then increasing asthma from 2001 to 2010.  The gap in data is because the method for making the determination of asthma prevalence changed in the years between these two sets of data, so it is difficult to be sure that we are comparing apples to apples.  The apparent increase in asthma is very large in this time.  The odd thing is that the fraction of electric power generation by coal fell in this time and of that falling fraction, more and more effort was made to produce the power from coal more cleanly.  If asthma increased from 3% of the population to 8% during this time, there must be factors causing asthma which are far more important than the contribution that might be made by coal.

It is interesting that the increase in asthma since 2011 is primarily due to an increase in asthma among Black Americans.  Now it might be that coal-fired power plants are much more likely to be upwind of Black neighborhoods, the white Progressive Elitists being so efficient at Not in My Back Yard special interest tactics.  But let us remember this difference as we look at the following data and remember that people of different ethnic backgrounds do often have different susceptibilities to different diseases.

Now this is fascinating data.  Note how dramatically asthma prevalence changes by gender and age.  Surely exposure to the emissions of pollutants does not change so dramatically by age or gender as this.  It might be possible that the susceptibility to pollutants does change this dramatically, but that sure would seem to be a stretch.  Boys to 14 years old are much more likely to have asthma than girls, but girls have a steadily increasing probability of becoming asthmatic through age 17 and then have a slight general decrease in asthma after that, while remaining much more likely than males to have asthma at all ages 18 and beyond.  But males after 14 have a substantial lowering of probability to about age 44, before their probability starts to rise again.  This happens despite the fact that men are more likely than women to spend more time outside in their adult years, where they are supposedly being more directly assaulted by the emissions of coal-fired power plants.  These age and gender behaviors sure seem more likely to suggest a primarily internal biochemical cause as the primary cause of asthma.

Now here it is interesting to note that ethnic Asians are much less likely to have asthma.  I doubt that ethnic Asians are much less likely to live downwind from coal-fired power generators than is the average American.  In fact, a disproportionate fraction of them live in California, which despite its history of smog, has few coal-fired power plants.  Also, while Native Americans have high rates of asthma, most of them live in the American West where coal-fired power plant density is low compared to that in the East.  For some reason, people of multiple race have much higher rates of asthma than any other racial group, except those of Puerto Rican descent, who are about twice as likely as White Americans to suffer asthma.  Once again, this would all seem more likely to point to asthma causes with more of a basis in human biochemistry than in exposure to coal-fired power plant emissions.  Apparently, it is also very bad to have a low income.

By area of the country, it is slightly worse to be from the Northeast and Midwest than from the South and West.  It is worse to be from outside a metropolitan area than from inside one, though the difference is small.  In general, this makes one suspicious of the idea that pollution is an important cause of asthma.  To be sure, one might question whether the use of insecticides by farmers might be the reason for higher rates outside of cities, but one would think if this were true that this would be well-documented.  Besides, insecticides are actually used heavily in cities to fumigate dense housing from cockroaches and other insect inhabitants and mice and rats.  Metro areas are hardly free of similar insecticides as are found in the country.  The slightly greater non-metropolitan asthma percentage is more likely due to natural allergens such as pollen then it is to man-made chemicals.  Many people with asthma have a very rough time when pollen levels are high.  Again, this is a suggestion that the main causes of asthma are not environmental, but genetic or internal human biochemistry combined with natural irritants.  This is so much the case that there is a small advantage in living in a metropolitan area where overall human emissions pollutant concentrations are much higher than in the non-metropolitan areas.

Of those who have asthma, are they more likely now than earlier to have more asthma attacks?  Well no.  The graph above shows a slight drop in the number having attacks in the last 12 months, whether children or adults.  If the causes of asthma were environmental and those environmental factors were getting worse to cause an increase in the number of people reporting that they have asthma, then would it not be likely that the percentage of those with asthma who had attacks in the last 12 months would be increasing?  That it is not seems to suggest a likelihood that asthma is caused by human biological factors and/or more people are becoming aware of what asthma is and are becoming conscious of having the disease.

Now, let us examine the data for those who have actually had an asthma attack in the last 12 months.  Among those who have asthma, the percentage of each group having an asthma attack in the last 12 months varies very little.  The very small differences in the percentage of each ethnic group's asthma population having an asthma attack in the last 12 months inclines one toward the idea there may be an asthma gene which one either has or does not have.  The very similar percentages by region tends to argue that coal-fired power plants are at most a small factor and that environment generally is likely also to be a small factor.

This map of asthma incidence is remarkable.  It is interesting that there are sharp gradients by state.  Texas and Louisiana have low incidences, while New Mexico and Oklahoma have relatively high incidences of asthma in their populations.  Washington and Oregon on the West Coast have high incidences, but California has a low incidence.  All of the Rocky Mountain states have high incidences, despite those states not being noteworthy for pollution.  A narrow band of states across the middle of the Great Plains has relatively high incidences, while states north and south of the band have low incidences.  All of the South has a low incidence and all of the Northeast above the Mason-Dixon line has a high incidence.

The EPA makes the false claim that half the mercury in the atmosphere comes from coal-fired power plants.  I proved this nonsense in my blog post Evaluating the Mercury Emissions Danger from Coal-Fired Power Plants.  In that post, I showed that any mercury output from the coal-fired power plants was overwhelmed by natural sources of mercury in the atmosphere.  I showed that there was a complete lack of correlation between the EPA map showing their claimed power plant mercury emissions and actual measurements of mercury precipitation from the atmosphere.  However, their mercury emissions map may be of use here as a general measure of the pollutant output of coal-fired power plants, such as it is, around the country.  If the plant is supposedly not removing mercury output, then there may be other pollutants it is not removing in proportional measure.  So, here is that map:

Now comparing this map to the asthma prevalence by state in the map above this one, it is seen to be plausible that the high asthma incidences in the states Missouri, Illinois, Indiana, Ohio, Pennsylvania, and Kentucky might be due to emissions from coal-fired power plants.  But, there is almost no coal-fired power plant emission in Washington, Oregon, and Idaho to explain their high asthma incidences.  The large concentration of coal-fired power plants in East Texas where most of the state population is coexists with a very low incidence of asthma in Texas and downwind Louisiana.  The high incidence of coal-fired power plants in northern Alabama and Georgia near those states highest population centers coexists with a low rate of asthma in those states.  Oklahoma has a high rate of asthma, but its coal-fired power plants are almost all downwind of its population centers in Oklahoma City, Tulsa, Broken Arrow, Norman, Lawton, and Edmond.  It is also hard to understand how West Virginia, Virginia, Maryland, North Carolina, and South Carolina can have low incidences of asthma with so many coal-fired power plants.  In short, there is no correlation between the coal-fired power plant emissions and the incidence of asthma.

This is not too surprising given that the CDC started its slide presentation on asthma by stating that its causes were generally not known.  The CDC has decades of skill in measuring and mapping the regional incidence of diseases and tracing them back to common sources.  If coal-fired power plants were a significant cause of asthma, surely they would have identified this cause long ago.

You would never know about this glaring lack of evidence from the ads being shown of asthma-suffering children on TV lately, which the Progressive Elitist propagandists are shamelessly blaming on coal-fired power plants.  This claim is as false and base as the claim that man's use of fossil fuels will cause catastrophic degradation of the environment and represents a threat to man's continued existence.  There is no rational justification for the claims in either case made by the alarmists who are endeavoring without let-up to further empower the government to eliminate our equal, sovereign individual rights to life, liberty, property, and the pursuit of our own happiness.  It can only be understood as a power grab, allowing Progressive Elitists to dictate our values to us and to micromanage our lives.

Update 21 April 2015:  If man-made global warming is causing asthma attacks as the EPA and Obama claim, why is it that hospital admissions for asthma are lower in the summer than in the winter?  If the claim is that smog and ozone are playing a role, then how is it that asthma prevalence has increased while both smog and ozone have generally decreased each decade since 1970?  What is more, ozone and smog levels caused by man are surely higher in metropolitan areas than outside them, so why is the prevalence of asthma lower in metropolitan areas than in non-metropolitan areas?  The EPA claims that common pollutant emissions are down 62% as of 2013 from levels in 1980!  Smog is down 33% since 1980 according to the EPA.  Is it possible to be more irrational than this Obama EPA is in its asthma claims?