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It has long been known that children living in congested cities have higher rates of asthma. All those vehicles, all that pollution. A recent study found that prenatal air pollution exposure is also important in asthma development.

Pregnant women exposed to high levels of tiny ultra-fine particles (UFPs, <0.1 µm) in the air were more likely to have children who developed asthma in the preschool years. Both boys and girls were affected, but high levels seemed to be especially harmful for girl babies exposed late in pregnancy.

Many of the women lived near major roadways with high traffic density - exposure to ultra-fine particles is greater there.

Ultra-fine particles are so small (<0.1 µm) that they can be considered nanoparticles. Their small size makes them so harmful - they can enter the lungs easily and from there travel throughout the body (including the organs), where they cause inflammation and other health effects. Unfortunately, ultra-fine particles are not regulated or routinely monitored in the United States.

From Science Daily: In utero exposure to tiny air pollution particles is linked to asthma in preschoolers

Women who were highly exposed to ultra-fine particles in air pollution during their pregnancy were more likely to have children who developed asthma, according to a study published in the American Journal of Respiratory and Critical Care Medicine in May. ...continue reading "Pregnancy and Air Pollution Linked to Asthma in the Children"

Earth. Credit: Wikipedia

Today is Earth Day, a good day to reflect on the state of the Earth. Our home. Think about the tremendous amount of air pollution in the air we breathe, of which two pollutants of concern are ozone and fine particulate matter.

The American Lung Association released its annual State of the Air 2021 report. Unfortunately, it reports that more than 40% of American (over 135 million people) are living in places with unhealthy levels of ozone or particle pollution.

Air pollution has all sorts of negative health effects (e.g. effects on brain, heart disease, premature death) The report also points out that the burden of living with the unhealthiest air is not shared equally by everyone. A report finding: “People of color are over three times more likely to be breathing the most polluted air than white people.”

On the other hand, things would be even worse without the fifty year old Clean Air Act (passed in 1970, signed into law by President Nixon). The air quality data used in the report is collected at official monitoring sites across the United States by the federal, state, local and tribal governments. Note that wildfires added to levels of air pollution. It's not just industry, power plants, and vehicles.

Which cities in the US have the worst forms of air pollution? Los Angeles remains the city with the worst ozone pollution in the nation. Fairbanks, Alaska is currently the metropolitan area with the worst short-term particle pollution for the first time. And Bakersfield, California returned as the most polluted for year-round particle pollution (for a second year in a row).

Are you wondering about the ozone and particle pollution in X, Y, or Z locations? Go check out the report. Just keep in mind that it is NOT looking at specific chemical emissions in the air, but only 2 things: ozone and fine particulates.

Short summary, from The Hill: Shocking new study finds 4 out of every 10 Americans live in areas with unhealthy air pollution

Easy to read, with lots of links. From the American Lung Association: State of the Air 2021

The report's 25 most polluted cities for ozone and particulate matter: Most Polluted Places to Live

High heat is not good for a developing baby during pregnancy. And neither is air pollution. A just published large study concluded that higher temperatures from climate change and increased air pollution (from ozone and fine particulates PM2.5) increases the risk of giving birth to premature, underweight, or stillborn children.

The researchers analyzed 68 studies, for a total of 32,798,152 births in the United States. Almost 33 million births! Another important finding was that those at highest risk were persons with asthma and minority groups, especially black mothers.

The researchers point out that animal studies find the same things: "that both air pollutant and heat exposure may contribute to adverse obstetrical outcomes". So there is lots of support for these findings of harmful effects.

Another recent study (by Univ. of California researchers) drew similar conclusions: that exposure to heatwaves during the week before birth was strongly linked to an increased risk of preterm delivery. And the hotter the temperature or the longer the heatwave, the greater the risk.

Since the long-term forecast is for increasing temperatures and longer duration heat waves throughout the world, these findings are very worrisome.

The study published in the JAMA Network Open (a Journal of the American Medical Association): Association of Air Pollution and Heat Exposure With Preterm Birth, Low Birth Weight, and Stillbirth in the USA: Systematic Review

A NY Times discussion of the findings: Climate Change Tied to Pregnancy Risks, Affecting Black Mothers Most

Discussion of earlier study (Feb. 2020) from Science Daily: Heatwave exposure linked to increased risk of preterm birth in California

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"