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A new study has nicely illustrated how extreme air pollution gets quickly into a person and has negative health effects, but improvement occurs when the exposure to the air pollution ends.

It has long been known that long-term exposure to air pollution is associated with increased heart disease and death from heart disease (cardiovascular morbidity and mortality). But now University of California researchers showed that even relatively short term exposure to high levels of air pollution has negative health effects, such as an increase in inflammation and systemic oxidation (which are linked to heart disease).

The researchers looked at 26 healthy young adults from Los Angeles who visited Beijing for a 10 week period during the summers of 2014 and 2015. They looked at both health effects (such as levels of inflammation) and also what pollutants are found in their bodies. And yes, they found both markers for inflammation and heart disease, as well as high levels of pollutants after being in Beijing for 10 weeks.

Beijing is much more polluted than Los Angeles. For example, levels of small particles in the air (PM2.5) was on average 371% higher in Beijing than Los Angeles, and concentrations of nitrogen dioxide, sulfur dioxide, carbon monoxide, polycyclic aromatic hydrocarbons (PAHs), and ozone were also at higher levels in Beijing than Los Angeles. [Note: PAHs are a group of combustion-originated air pollutants.]

Interestingly, Los Angeles air used to be much more polluted, but environmental policies and regulations resulted in the air becoming cleaner. In other words, steps can be taken to lower levels of air pollution, with would result in health benefits for everyone.

Excerpts from Medical Xpress: Study finds even a short-term visit to a severely polluted city is bad for your health  ...continue reading "Even Short-term Exposure to High Levels of Air Pollution Is Bad For Your Health"

Several recent studies have highlighted the negative effects of air pollution on the brain, specifically from the tiniest particles in polluted air (called PM 2.5). These tiny particles get to the human brain and cause all sorts of damage. Even at levels within government guidelines.

Two studies found that with higher chronic (daily) exposure to PM2.5 air pollution there were structural changes to the brain. Which is negative to brain health, of course.

With chronic exposure to higher levels of  PM2.5 air pollution: one study found greater declines in memory and more Alzheimer's-like brain atrophy in older women in the USA; and the second study found that higher prenatal exposure was associated with a smaller corpus callosum (a part of the brain) later in childhood. Thus structural changes in the brain!

The tiniest particles are 2.5 micrometers or less in diameter, about 1/30th the width of human hair - and referred to as PM2.5. These fine particles are produced by all sorts of combustion, including motor vehicles, power plants, residential wood burning, agricultural burning, some industrial processes, and forest fires. Typically there is much more exposure to PM2.5 in busy urban streets, and less in quiet suburban streets.

Researchers in Barcelona, Spain found that long-term higher prenatal exposure to PM2.5 particulate matter, especially during the last trimester of pregnancy, is associated with a smaller corpus callosum in children between the ages of 8 and 12 years. This is an important finding because a smaller (reduced volume) corpus callosum is found in ADHD (attention deficit hyperactivity disorder), ASD (autism spectrum disorder), and hyperactivity. So here we see a structural change in the brain from air pollution at PM2.5 levels that are considered acceptable (within guidelines) by the European Union!

A report called The State of Global Air/2018 stated that studies show that long-term exposure to PM2.5  particles in the air "is the most consistent and robust predictor" of death from heart disease and stroke, lung cancer, and respiratory illnesses. And then there are nitrogen oxides and ozone, which are also linked to death. There are also nanoparticles (e.g., from friction of tires being used) that penetrate deep into the human body.

A 2018 The Guardian article called air pollution "the new tobacco". And that it's time to tackle this epidemic. Yup. Unfortunately, current air pollution standards are being relaxed in all sorts of ways under the current U.S. administration. Beware!

First study. Excerpts from Medical Xpress: Exposure to PM 2.5 pollution linked to brain atrophy, memory decline  ...continue reading "Air Pollution and the Brain, Part 1"

The last few years has seen a loosening of all sorts environmental rules here in the United States, including air pollution. The EPA (Environmental Protection Agency) is not looking out for ordinary people, but doing its best to be as accommodating as possible to big industry. Pollution standards and rules are going backwards! A lot.

[NY Times Dec. 2018 list of 78 environmental rules on the way out. Since then things have only gotten worse - see regulatory rollback tracker from Harvard Law School. Posts on air pollution and health effects.]

Which is why I'm now posting an article about 5 personal air pollution monitors that measure what is in the air around you -  whether in your home, workplace,  or outside. Some can be carried around, others meant to be set up indoors. Most are small, portable, and under $250 (Aeroquel is more expensive). They measure particulates in the air plus other things such as VOCs.

They are Atmotube, Plume LabAwairAeroqual, and Purple Air monitors. Purple Air monitors smoke, dust, and particulate pollution, and connects a person into an air quality network, so that there is "real time" monitoring. They all are a little different, and all look good. I really, really want an air pollution monitor!

Since this NY Times article was published, it appears that new versions of the pollution monitors (more advanced) are available from these companies.

Excerpts from a Nov. 30, 2018 article by Nellie Bowles in the New York Times: Do You Know What You’re Breathing?  ...continue reading "You Can Easily Measure the Air Quality Around You"

Two recent studies point out the dangers of air pollution to the developing fetus. The first study found an association with high levels of air pollution during pregnancy and lower IQ years later when the children were between the ages of 4 to 6 (as compared to women exposed to less traffic-related air pollution during pregnancy).

The second study found that soot (tiny carbon particles) from air pollution  (e.g. vehicle exhaust) are breathed in by the pregnant woman, and then make it to her placenta during pregnancy and cross over to the baby's side of the placenta. (The placentas were collected and examined after delivery.) The fact that these tiny particles found in polluted air are breathed in by the pregnant woman and reach the baby's side of the placenta and accumulate, suggests to the researchers how air pollution causes harm to the fetus. They also found that the more particles the pregnant woman was exposed to throughout pregnancy, the more particles were detected on the baby's side of the placenta ("placental load").

The placenta used to be viewed as a barrier to toxins, but NOPE - it's not. (As we already know with alcohol and drugs, etc.)

But now some good news: In the first study, pregnant women who had higher levels of folate in their blood - meaning they had better nutrition and higher intake of folic acid during pregnancy, appeared to have a protective effect on the developing baby. As the researchers said: "Maternal folate levels may modify the impact of prenatal air pollution exposure on child cognition." In those with the lowest folate levels during pregnancy, the negative effects of air pollution during pregnancy on the developing fetus appeared to be the strongest (6.8 points lower IQ). Folate is naturally occurring in many fruits, vegetables, beans, peas, and nuts, and is in the form of folic acid in vitamin supplements. Best is a good diet.

From Medical Xpress: Offspring of pregnant women exposed to high level of pollutants may have lower IQs   ...continue reading "Air Pollution Has Harmful Effects During Pregnancy"

We love plastic, and use plastics in basically everything. However, with time and wear and tear, plastics are worn down, and little plastic microparticles are released into the air. These microplastics are less than 5 mm (millimeters) long - about the size of a sesame seed or less. Studies are finding them everywhere, including our drinking water, in seafood, all sorts of foods, the dust, and the air in our homes and workplaces. And of course microplastics wind up in our bodies (whether ingesting them through food and beverages, or breathing them in so that they go to the lungs). No one really knows what effects they have on human health, but studies are starting to find harms to animal health.

Well...  now there is another cause for concern. A new study finds more than expected amounts of microplastic particles in remote parts of the world (the Alps and Arctic!) where no one expected to find them in large amounts. The German researchers report that the main types of plastic microparticles they found were from varnish, rubber, polyethylene, and polyamide (nylon). The particles are transported through the atmosphere by winds and air currents. View it as air pollution. Bottom line: As humans continue to use more and more plastics, and more gets released into the air, this means we all will absorb more and more microplastics with still unknown impacts on health.  Ultimately we all will have to address this issue.

Excerpts from The Atlantic: A Worrisome Discovery in High Arctic Snowfall

In just the past decade, scientists have discovered that microplastics—defined as any plastic detritus that’s about the size of a sesame seed or smaller—are a major new pollutant, the spread of which we’re only now understanding. Microplastics are present in 94 percent of tap water in the United Statesaccording to one study. They form as larger plastic items—toys, clothing, paint chips, car tires—get worn down and torn to shreds ...continue reading "Microplastics Are Found Even In Arctic Snow"

Once again research is finding effects on health from nanoparticles and air pollution - this time the heart. Tiny air pollution particles less than 100 nm (nanometers) in size are typically called "ultrafine  particles", but actually they are so small that they are nanoparticles. They are NOT regulated in the United States, even though many researchers feel that they are the most dangerous particles found in air pollution. This is because their small size means they are easily inhaled and then get into human lungs and organs, and even cells. Where do they come from? They get into the air from industry (e.g. metal processing, power generation plants), from the exhaust of vehicles (from vehicle combustion), and from friction when using vehicle brakes.

The researchers write that the air in polluted urban areas and next to roads have a lot of these iron-rich nanoparticles from vehicle combustion and friction. And also that these particles are "strongly magnetic". Earlier research in the urban Mexico City area found that these nanoparticles were found in the brains of all people, starting at young ages (they had died suddenly in accidents, which is why the brains could be analyzed). Keep in mind that Mexico City has high levels of air pollution, but so do many other urban areas throughout the world.

This latest study from a team of international researchers analyzed both the hearts of young people who died suddenly, as well as animals - and they compared the results from those exposed to high levels of urban air pollution (Mexico City metro area) and those from areas with low amounts of air pollution (the "controls"). The results were not good: all hearts from the Mexico City area (high air pollution) had lots of the same iron-rich magnetic nanoparticles ("in abundance") that are found in the air. Billions of nanoparticles in each heart, even in the youngest 3 year old child!

These nanoparticles are inhaled, then enter the person's circulatory system (carried by blood cells), and then into cardiac cells. As the researchers stated: the magnetic nanoparticles were "highly abundant in left ventricular samples from young subjects exposed to high concentrations of particulate air pollution above current US EPA standards. The organelles and structures containing abundant nanoparticles displayed substantial abnormality". Hearts from low pollution areas appeared normal.

This could explain why people living in polluted urban areas, including in the United States, have a greater risk for heart disease (cardiovascular disease), including heart attacks and strokes, as well as premature death. This research also highlights why we need to regulate these tiny particles in the air. As the researchers said: "This is a serious public health concern".

Excerpts from The Guardian: Billions of air pollution particles found in hearts of city dwellers   ...continue reading "Pollution Nanoparticles Found In Human Hearts"

Researchers measured chemicals in the air in 2 cities (Boulder, CO and Toronto, Canada) and found equally high levels of 2 chemicals in the air during morning commute times - benzene (from vehicle exhaust) and a type of siloxane (from personal care products). What? This study's results make a strong case for reading ingredient lists of personal care products (especially lotions, shampoos, deodorants, antiperspirants) - and avoiding those containing siloxane (which emits volatile organic compounds or VOCs!).

If you consider siloxane and fragrances (which can contain a long, long list of chemicals, including VOCs) as significant sources of air pollution, you might not want to breathe it in or put in on your skin to be absorbed.  Bottom line: Read labels! From Science Daily:

Personal care products contribute to a pollution 'rush hour'

When people are out and about, they leave plumes of chemicals behind them -from both car tailpipes and the products they put on their skin and hair. In fact, emissions of siloxane, a common ingredient in shampoos, lotions, and deodorants, are comparable in magnitude to the emissions of major components of vehicle exhaust, such as benzene, from rush-hour traffic in Boulder, Colorado, according to a new CIRES and NOAA study.  ...continue reading "Personal Care Products and Air Pollution"

Air pollution is linked to so many negative health effects, now another one - poorer quality sperm. In this study 6475 males  (ages ranged from 15–49 years) had their sperm analyzed as part of a standard medical examination program in Taiwan. They were also able to get air pollution measurements for each person's address for that time period. They found that both short-term and long-term exposure to higher levels of fine particulate matter (PM2.5) pollution were linked to lower numbers of sperm being normal in size and shape (sperm morphology), but with a higher concentration of sperm. Perhaps a  compensatory phenomenon?

The researchers pointed out that other studies have also found effects from air pollution on sperm. Since this study only analyzed a person's sperm one time, the findings are correlational (they observed an association, but couldn't definitely say it caused the effect). [Some other posts on sperm qualityhere, here, here.] From Medical Xpress:

Air pollution linked to poorer quality sperm

Air pollution, particularly levels of fine particulate matter (PM2.5), is associated with poorer quality sperm, suggests research published online in Occupational & Environmental Medicine. Although the size of the effect is relatively small in clinical terms, given how widespread air pollution is, this might spell infertility for a "significant number of couples," say the researchers.

Environmental exposure to chemicals is thought to be a potential factor in worsening sperm quality, but the jury is still out on whether air pollution might also have a role. To explore this possibility further, the international team of researchers looked at the impact on health of short and long term exposure to fine particulate matter (PM2.5) among nearly 6500 15 to 49 year old men in Taiwan.

The men were all taking part in a standard medical examination programme between 2001 and 2014, during which their sperm quality was assessed (total numbers, shape/size, movement) as set out by World Health Organization guidelines. PM2.5 levels were estimated for each man's home address for a period of three months, as that is how long it takes for sperm to be generated, and for an average of 2 years, using a new mathematical approach combined with NASA satellite data.

A strong association between PM2.5 exposure and abnormal sperm shape was found. Every 5 ug/m3 increase in fine particulate matter across the 2 year average was associated with a significant drop in normal sperm shape/size of 1.29 per cent. And it was associated with a 26 per cent heightened risk of being in the bottom 10 per cent of normal sperm size and shape, after taking account of potentially influential factors, such as smoking and drinking, age or overweight. However, it was also associated with a significant increase in sperm numbers, possibly as a compensatory mechanism to combat the detrimental effects on shape and size, suggest the researchers. Similar findings were evident after three months of exposure to PM2.5. [Original study.]

A study of 60 million Americans 65 years old and older (the entire Medicare population) found that long-term exposure to airborne fine particulate matter (PM2.5) and ozone at concentrations below current national standards increases the risk of premature death ("all cause mortality") even when the levels are below current national standards. This effect was most pronounced among racial minorities and people with low income. The national standards are called National Ambient Air Quality Standards (NAAQS), and they are established by the U.S. Environmental Protection Agency (EPA).

Note that PM2.5 refers to fine particles in the air smaller than 2.5 micrometers - these are truly small particles. It is thought that these tiny particles contribute to the development of potentially fatal diseases various ways - by causing chronic inflammation, and also because they slip past the body's defenses and can be absorbed deep into the lungs and bloodstream. They are not sneezed or coughed out the way larger natural particles (like airborne soil and sand) are removed from the body's airways.

These study results are a strong argument in support of the view that our air needs to be protected and standards need to be strengthened - not loosened. Earlier posts on this topic have found links between air pollution (especially fine particulate matter smaller than 2.5 micrometers) and cognitive decline and dementia in older women, strokes, high blood pressure, an increase in death (especially cardiovascular disease), etc. From Medical Xpress:

Study of US seniors strengthens link between air pollution and premature death

A new study of 60 million Americans—about 97% of people age 65 and older in the United States—shows that long-term exposure to airborne fine particulate matter (PM2.5) and ozone increases the risk of premature death, even when that exposure is at levels below the National Ambient Air Quality Standards (NAAQS) currently established by the U.S. Environmental Protection Agency.

The Harvard T.H. Chan School of Public Health researchers found that men, blacks, and low-income populations had higher risk estimates from PM2.5 exposure compared with the national average, with blacks having mortality risks three times higher than the national average. The results showed that if the level of PM2.5 could be lowered by just 1 microgram per cubic meter (ug/m3) nationwide, about 12,000 lives could be saved every year. Similarly, if the level of ozone could be lowered by just 1 part per billion (ppb) nationwide, about 1,900 lives would be saved each year.

"This is a study of unprecedented statistical power because of the massive size of the study population. These findings suggest that lowering the NAAQS for fine particulate matter will produce important public health benefits, especially among self-identified racial minorities and people with low incomes," said Francesca Dominici, principal investigator of this study and professor of biostatistics at Harvard Chan School and co-director of the Harvard Data Science Initiative.

The researchers examined Medicare claims records of 60 million Americans 65+ over a seven-year period, representing 460 million person-years of follow-up. They also estimated air pollution levels at each 1 kilometer grid for the entire U.S. upon which the claims data could be overlaid and interpreted. .... By relying on this well-validated prediction model, the team was able to include subjects who live in unmonitored and less-populated areas so that the effects of air pollution on all 60 million people could be analyzed regardless of whether they lived in urban, suburban, or rural areas. "This study shows that although we think air quality in the United States is good enough to protect our citizens, in fact we need to lower pollution levels even further," said Schwartz. [Original study in New England Journal of Medicine.]

This is a thought-provoking study that looked at environmental quality and cancer incidence in counties throughout the US. The researchers found that the more polluted the county, the higher the cancer incidence. An increase in cancer rates was associated with poorer air quality and the "built environment" (such as major highways). They correctly point out that many things together can contribute to cancer occurring - and this is why looking at how polluted the air, water, etc. together is important.

They looked at the most common causes of cancer death in both men (lung, prostate, and colorectal cancer), and women (lung, breast, and colorectal cancer). They found that prostate and breast cancer demonstrated the strongest associations with poor environmental quality. [Original study.]

The researchers point out that about half of cancers are thought to have a genetic component, but therefore the other half have environmental causes. Other studies already find that environmental exposures (e.g., pesticides, diesel exhaust) are linked to various cancers. But this study was an attempt to look at interactions of various things in the environment with rates of cancer - because we all are exposed to a number of things simultaneously wherever we live, not just to exposures to one thing. Thus this study looked at associations in rates of cancer. 

Of course there is also a lifestyle contribution to many cancers that wasn't looked at here (nutrition, alcohol use, exercise). They also pointed out that many counties in the US are large and encompass both very polluted and non-polluted areas - and that those counties should be broken up into smaller geographic areas when studied. [More air pollution studies.] From Science Daily:

Poor overall environmental quality linked to elevated cancer rates

Nationwide, counties with the poorest quality across five domains -- air, water, land, the built environment and sociodemographic -- had the highest incidence of cancer, according to a new study published in the journal Cancer. Poor air quality and factors of the built environment -- such as the presence of major highways and the availability of public transit and housing -- -- were the most strongly associated with high cancer rates, while water quality and land pollution had no measurable effect.

Previous research has shown that genetics can be blamed for only about half of all cancers, suggesting that exposure to environmental toxins or socioeconomic factors may also play a role. "Most research has focused on single environmental factors like air pollution or toxins in water," said Jyotsna Jagai, research assistant professor of environmental and occupational health in the University of Illinois at Chicago School of Public Health and lead author of the study. "But these single factors don't paint a comprehensive picture of what a person is exposed to in their environment -- and may not be as helpful in predicting cancer risk, which is impacted by multiple factors including the air you breathe, the water you drink, the neighborhood you live in, and your exposure to myriad toxins, chemicals and pollutants."

To investigate the effects of overall environmental quality, the researchers looked at hundreds of variables, including air and water pollution, pesticide and radon levels, neighborhood safety, access to health services and healthy food, presence of heavily-trafficked highways and roads, and sociodemographic factors, such as poverty. Jagai and her colleagues used the U.S. EPA's Environmental Quality Index, a county-level measure incorporating more than 200 of these environmental variables and obtained cancer incidence rates from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program State Cancer Profiles. Cancer data were available for 85 percent of the 3,142 U.S. counties.

The average age-adjusted rate for all types of cancer was 451 cases per 100,000 people. Counties with poor environmental quality had higher incidence of cancer -- on average, 39 more cases per 100,000 people -- than counties with high environmental quality. Increased rates were seen for both males and females, and prostate and breast cancer demonstrated the strongest association with poor environmental quality.

The researchers found that high levels of air pollution, poor quality in the built environment and high levels of sociodemographic risk factors were most strongly associated with increased cancer rates in men and women. The strongest associations were seen in urban areas, especially for the air and built environment domains. Breast and prostate cancer were most strongly associated with poor air quality.