Air Pollution Reduces Intelligence and Life Expectancy

health effects of air pollution

Story at-a-glance -

  • According to the Health Effects Institute, 95 percent of the world is breathing polluted air and studies find Americans spend 92 percent of their time indoors where the air may be even more polluted than outside
  • Research shows air pollution adversely affects intelligence and measurably reduces language and math skills; children exposed to air pollution have an increased risk of early onset and persistent asthma, linked to early education drop out
  • Carbon particles have been found in placental tissue, demonstrating pregnant women breathing polluted air may be passing toxins to their unborn children as the particles are absorbed into the bloodstream through the lungs
  • Particulate pollution absorbed into the bloodstream also increases the risk of developing chronic kidney disease and indoor pollutant per- and polyfluoroalkyl substances, found in carpeting, clothing and food wrapping, damage kidney function

By Dr. Mercola

According to a recent report by the Health Effects Institute,1 95 percent of the world live in areas where the pollution levels are higher than deemed safe by the World Health Organization (WHO). This makes air pollution the fourth largest cause of death, following high blood pressure, diet and smoking.

Fine particulate matter (PM) concentration exceeds 10 micrograms per meters cubed (ug/m3) for 95 percent of the world, and nearly 60 percent live in areas where the PM exceeds even the least stringent WHO air quality target of 35 ug/m3.2 Fine PM measuring less than 2.5 micrograms (PM2.5) is one indicator of outdoor pollution levels.

Experts estimate exposure to PM2.5 contributes to more than 6 million deaths worldwide and plays a large role in increasing the risk of stroke, lung cancer and heart attack. Although many developed countries have made significant moves toward reducing air pollution, developing countries have fallen further behind as they struggle for economic growth.3

Bob O'Keefe, vice president of the Health Effects Institute, believes there's reason for optimism, though, as both China and India are taking steps to reduce pollution.4 Although the physical effects of air pollution are well-known, a recent study5 demonstrates it may cause a large reduction in intelligence, indicating damage of toxic air is far more significant than previously believed.

Air Pollution Damages Intelligence

Although data was collected on 20,000 people living in China, the researchers believe the findings are relevant to the entire world. They found6 language and arithmetic skills were affected, with the average impact on those tested equivalent to losing one year of education.

However, a member of the research team believes the effects may be even worse for the elderly and for those with a low education level. Calculating the loss in those individuals may increase damage to several years. The study authors concluded:7

"The damage on the aging brain by air pollution likely imposes substantial health and economic costs, considering that cognitive functioning is critical for the elderly for both running daily errands and making high-stake decisions."

According to this study, the longer people were exposed, the greater the damage. Language skills were the most dramatically affected, in men more than women. Researchers monitored individuals for more than four years.8 Other studies have found air pollution harms cognitive performance in students. However, this is the first to examine individuals of all ages and the differences between men and women.

Data from other studies have linked air pollution to high mortality in those who suffer mental disorders.9 It’s also been found to raise the risk of mental illness in children,10 and those living near busy roads have an increased risk of dementia.11

According to researcher Derek Ho, Ph.D., from Hong Kong Polytechnic University, air pollution likely affects cognition because "high air pollution can potentially be associated with oxidative stress, neuroinflammation and neurodegeneration of humans."12

Another member of the research team, Xi Chen at Yale School of Public Health, believes air pollution is most likely the cause of loss of intelligence rather than simply being correlated.

The team noted air pollution has a short-term impact on intelligence as well, which could have significant consequences for students who have to take crucial exams on polluted days. Dr. Aarash Saleh, from Doctors Against Diesel campaign, remarked:13

"This study adds to the concerning bank of evidence showing that exposure to air pollution can worsen our cognitive function. Road traffic is the biggest contributor to air pollution in residential areas and the government needs to act urgently to remove heavily-polluting vehicles from our roads."

Another study, conducted over 20 years in Sweden, demonstrated those with asthma — a potential health risk with exposure to air pollutants — were three and a half times more likely to leave school by the age of 16 and twice as likely to drop out of the university. This suggests exposure to pollutants at a young age may impact the future education and jobs of these children.14

Effects of Air Pollution Begin Before Birth

There is ample evidence air pollution triggers negative health conditions in adults and children, but recent research presented at the European Respiratory Society International Congress demonstrate tiny particles of carbon are capable of migrating through the lungs and the placenta.15

Previously, research has linked air pollution exposure in pregnant moms with premature birth, low birth weight, infant mortality and childhood respiratory problems. Although this new study adds to existing evidence, the work concerned the researchers, as they were surprised to find the number of particles present.

The team gathered data from five pregnant women who lived in London and were due for a planned cesarean section delivery. All of the women were nonsmokers and had a history of an uncomplicated pregnancy and each gave birth to a healthy baby. The women gave permission for the team to study the placenta after delivery.16

Analysis found 60 cells contained 72 small black areas believed to be carbon particles.17 On average, each placenta had nearly 5 square micrometers of this black substance. Lisa Miyashita, one of the research team from Queen Mary University, commented on the importance of the findings:18

"We’ve known for a while that air pollution affects fetal development and can continue to affect babies after birth and throughout their lives. We were interested to see if these effects could be due to pollution particles moving from the mother’s lungs to the placenta. Until now, there has been very little evidence that inhaled particles get into the blood from the lung."

Air Pollutants Damage Kidney Function

The kidneys are sensitive organs, reacting quickly to environmental toxins and medications. A recent study found a widely used household and industrial chemical, per- and polyfluoroalkyl substances (PFASs), may damage your kidneys.19 PFASs are used to create heat, water and oil resistance in applications such as carpeting, apparel, food paper wrappings and firefighting foams.

The chemicals are not biodegradable, and bioaccumulate through the food chain. People and animals are exposed through contaminated soil, food, water and air, and exposure has been linked to adverse health effects including low birth weight, delayed puberty and reduced immunological responses.20

Lead author, Dr. John Stanifer of Duke University, commented on the importance of understanding how the chemicals in the environment interact with each other and impact human health:21

"Because so many people are exposed to these PFAS chemicals, and to the newer, increasingly produced alternative PFAS agents such as GenX, it is critical to understand if and how these chemicals may contribute to kidney disease."

The literature review included toxicological studies of human and animal data as well as human epidemiological studies. These revealed significant association between PFAS exposure with poor overall kidney health and lower estimated glomerular filtration rate.22

The researchers also found a higher prevalence of chronic kidney disease. Stanifer23 was surprised at the amount of evidence supporting a link between PFAS exposure and kidney disease. As they are with so many other environmental toxins, researchers are still unclear how they interact to worsen kidney disease in those who also have other risk factors, such as diabetes and hypertension.

This is just one of three studies in recent months demonstrating the effect air pollution has on kidney function. The second was published in PLOS One by University of Michigan researchers who found air pollutants may trigger the development of chronic kidney disease.24

The third25 also evaluated the impact of environmental pollution on the kidneys and found long-term exposure to PM 2.5 was associated with an increased risk of rapid decline in renal function.

Clean Air Begins at Home

Studies show Americans spend nearly 92 percent of their time indoors,26 which means your indoor air is critical to your overall health. There are steps you may consider to improve the quality of air you breathe each day in your home, many of which are very cost-effective in the short run and may help significantly reduce your health care costs long-term.

Ventilation — One of the simplest and easiest ways to reduce pollution levels in your home is to open a couple of windows to create cross-ventilation. Since most new homes have little air leakage, opening the windows for as little as 15 minutes each day can improve the quality of the air you're breathing.

An attic fan may reduce your air conditioning costs and bring in fresh outdoor air. Kitchen and bathroom fans venting outside help remove contaminants from these rooms.27 Some builders are installing heat recovery ventilation systems to help prevent condensation and mold growth and improve indoor air quality in energy efficient homes.28

The same principles apply to ventilating your car. Chemicals from plastics, solvents, carpet and audio equipment in new cars add to the toxic mix in your car's cabin. The "new car smell" can contain up to 35 times the health limit for VOCs, as discussed in my previous article, "What’s in That New Car Smell?"

However, when driving in heavy traffic you’ll want to reduce air pollution from car exhaust by closing your windows and recirculating the air in your car until you are out of traffic.

Purification — An inexpensive method of removing toxins from the air and destressing your environment is using plants as discussed in the video below.29 Also see "12 Healthy Houseplants That Improve Your Indoor Air Quality" for a list of plants you may consider.

A high-quality air purifier using photocatalytic oxidation (PCO) is one of the best technologies available. Rather than merely filtering the air, PCO actually cleans the air using ultraviolet light. PCO transforms the pollutants into nontoxic substances. In addition to using them in your home, portable air purifiers are available to take with you when you work or travel.

Filtration — Water filters function to reduce the amount of airborne chlorine during a bath or shower.30 Shop for a filter with NSF/ANSI 177: Shower Filtration Systems-Aesthetic Effects. These filters are tested by a third party to make sure they effectively remove chlorine.31

Also vacuum your floors regularly using a HEPA filter vacuum cleaner or, even better, a central vacuum cleaner which can be retrofitted to your existing house. Standard bag or bagless vacuum cleaners are another primary contributor to poor indoor air quality.

A regular vacuum cleaner typically has about a 20 micron tolerance. However, far more microscopic particles flow right through the vacuum cleaner than it actually picks up. Beware of cheaper knock-offs professing to have "HEPA-like" filters — get the real deal.

Cleaning — Avoid hanging dry-cleaned clothing in your closet as soon as you bring them home. Instead, hang them outside for an entire day or two if possible. Better yet, see if there's an eco-friendly dry cleaner in your city using some of the newer dry cleaning technologies, such as liquid CO2.

Most cleaning products, air fresheners and scented candles contribute to poor indoor air quality. Research has linked once-weekly use of cleaning products with a 24 to 32 percent higher risk of progressive lung disease.32

Fortunately, there are safe, cost-effective and efficient options, including soap and water, or vinegar and baking soda.33 Strategies in my previous article, "Are Household Products Killing Us?" may help reduce your toxic load. Consider these suggestions to clean your home using simple products you may already have in your cabinets.

  • Borax — This agent acts as a whitener and will boost your detergent power. Add between one-fourth cup and 1 cup to your laundry, depending on the size of your load.
  • Vinegar — A weak acid, this common liquid is a natural cleaning and deodorizing substance. Consider adding between one-fourth cup and one-half cup to your laundry with your detergent and wash as usual. Don't mix the borax with vinegar in the same load as they neutralize each other. Vinegar is also a good general all-purpose cleaner for your kitchen and bathroom, and works great for cleaning mirrors and windows.
  • Homemade scouring powder — Make your own safe scouring powder for soap scum in the bath by combining two parts baking soda, and one part each of borax and salt.

Service your appliances — A poorly maintained furnace, space heater, hot water heater, water softener, natural gas heater or stove and other fuel burning appliances may leak carbon dioxide or nitrogen dioxide. Have your appliances serviced per the manufacturer’s recommendations to reduce potential indoor air pollution.

Your air conditioner may also be a source of dangerous bacteria. On several occasions, outbreaks of Legionnaires’ disease have been traced back to contaminated air conditioner units.

Your air conditioner compressor might be outside your house, but inside, often in the attic or basement, is where the condensation occurs. Mold grows in damp and humid environments. Use a dehumidifier and air conditioner to keep your humidity under 50 percent. Keep the units cleaned so they aren't a source of pollution.

The air ducts from your forced air heating and air conditioning units can be a source of pollution in your home. If there is mold growth, a buildup of dust and debris or if the ducts have become home to vermin, it's time to call a professional and have them cleaned.

Prevention — Ask smokers to go outside. Secondhand smoke from cigarettes, pipes and cigars contains over 200 known carcinogenic chemicals, endangering your health.

Test for radon, a colorless, odorless gas linked to lung cancer. It can get trapped under your home during construction and may leak into your air system over time. Radon testing kits are a quick and cheap way to determine if you are at risk.

Avoid storing paints, adhesives, solvents and other harsh chemicals in your house. If you must have them, keep them in a detached garage or shed. Avoid using cookware with nonstick coating, as these pots and pans can release toxins into the air when heated.

Avoid powders, whether cleansing scrubs, talcum or other personal care powders — these can be problematic as they float and linger in the air after each use. Many powders are allergens due to their tiny size, and can cause respiratory problems.