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Air pollution is harmful on so many levels for all of us, (See recent Dec.post on harmful air pollution effects on pregnancy.) From Reuters Health:

Heart experts warn of air pollution dangers

Air pollution should be one of the avoidable heart risk factors - just like smoking and excess fat - that doctors warn patients to steer clear of, according to a new statement from 20 heart experts.

Citing pollution’s heavy toll on cardiovascular health, the panel urges people to take steps to protect themselves from breathing heavy traffic fumes or industrial air pollution whenever possible, and public officials to pass laws to reduce air pollution.Air pollution causes more than 3 million deaths worldwide each year and causes 3.1 percent of all cases of disability, Storey and his coauthors write in the European Heart Journal.

Air pollution is also ninth most important on a list of modifiable heart-disease risk factors - ranking above low physical activity, high-salt diet, high cholesterol and drug use, the authors point out.

Although gaseous air pollutants can be dangerous too, Storey said, airborne particles are the biggest contributor to cardiovascular disease because they cause inflammation of the lungs and enter the circulation, inflaming blood vessels, provoking clots and causing heart rhythm disturbances.

Particulate matter includes coarse particles from road dust, construction work and industrial emissions and fine particles from traffic, power plants and industrial and residential burning of oil, coal or wood for heating. The bulk of particulate air pollution is made up of these fine particles, known as PM2.5, that are less than 2.5 micrometers - about one fifth the size of visible dust. In 2013, the U.S. Environmental Protection Agency lowered the 24-hour exposure limit to an average of 12 micrograms.

European studies have found that PM2.5 levels are often markedly higher near heavy traffic zones compared to elsewhere in the same city, and that the levels can more than double during rush hours, according to the position statement.

Some of the authors’ advice for people to protect themselves is as simple as walking, cycling and using public transportation instead of driving cars, and exercising in parks or gardens, rather than near busy roads. And everyone should avoid being outside when pollution is highest, though this is especially important for infants, elderly and people with heart problems, the authors say.People who live in heavily polluted areas should also consider ventilation systems with filtration in their homes, since a large portion of outdoor pollution can penetrate buildings.

The use of fossil fuels for heating and energy should also be decreased, according to the statement.

Studies have shown even short-term exposure to high PM2.5 levels increases deaths from heart disease and respiratory disease, and that people living in places with high PM2.5 have an 11 percent greater risk of dying from heart attacks, strokes and heart failure than those who live in cleaner areas.

Once again air pollution is linked to health problems, this time exposure during pregnancy is linked to congenital malformations (what are commonly called birth defects). From Science Daily:

Smoke signals: New evidence links air pollution to congenital defects

The health effects of air pollution are a major concern for urban populations all over the world. A new study provides new evidence linking high exposure to air pollution to an increased risk of congenital malformations. Children, the elderly, and people with impaired respiratory systems (such as asthmatics) tend to be especially sensitive to the impact of exposure to ozone, nitrogen dioxide, sulphur dioxide, and particulate matter.

A recent study by Tel Aviv University researchers provides new evidence linking high exposure to air pollution to an increased risk of congenital malformations. The nationwide study is the first to assess the association between different modes of conception-assisted reproductive technology (ART) versus spontaneous conception (SC) -- and the risks of exposure to air pollution to each.

"Our results suggest that exposure to higher levels of air pollution during pregnancy is associated with various adverse pregnancy outcomes," said Prof. Lerner-Geva. "While our study mainly followed SC infants, we also had the opportunity to assess a small sample of pregnancies that were conceived through ART, and observed a higher impact of air pollution -- particularly with regard to ozone exposure. This is clearly a uniquely susceptible population that should be further explored."

For the study, funded by the Environmental Health Fund (EHF), the research team analyzed data on 216,730 born in Israel between 1997 and 2004. Air pollution data, including, levels of sulfur dioxide (SO2), particulate matter (PM10), nitrogen oxides (NOx), and ozone (O3) were obtained from air monitoring stations for the study period. Using a geographic information system, exposure to air pollution during both the first trimester and the entire pregnancy was assessed for each woman according to her place of residence.

The researchers found that exposure to PM10 and NOX pollutants throughout full-term pregnancies were associated with an increased risk of congenital malformations, with specific defects evident in the circulatory system (from PM10 and NOX exposure) and genital organs (from NOX exposure). They also discovered that exposure to SO2 and O3 in ART pregnancies were associated, although not significantly, with a higher risk of congenital defects.

Two studies finding various forms of air pollution having effects on the developing fetus - the first one (fine particulate air pollution) to autism, and the second (outgassing of new flooring) to later breathing problems.

From Medical Xpress: Fine particulate air pollution linked with increased autism risk

Women exposed to high levels of fine particulate matter specifically during pregnancy—particularly during the third trimester—may face up to twice the risk of having a child with autism than mothers living in areas with low particulate matter, according to a new study from Harvard School of Public Health (HSPH). The greater the exposure, the greater the risk, researchers found. It was the first U.S.-wide study exploring the link between airborne particulate matter and autism.

"Our data add additional important support to the hypothesis that maternal exposure to air pollution contributes to the risk of autism spectrum disorders," said Marc Weisskopf, associate professor of environmental and occupational epidemiology and senior author of the study.... Prior studies have suggested that, in addition to genetics, exposure to airborne environmental contaminants, particularly during pregnancy and early life, may affect risk of autism. This study focused specifically on the pregnancy period.

The study population included offspring of participants living in all 50 states in Nurses' Health Study II, a cohort of more than 116,000 female U.S. nurses begun in 1989. The researchers collected data on where participants lived during their pregnancies as well as data from the U.S. Environmental Protection Agency and other sources on levels of fine particulate matter air pollution (PM2.5)—particles 2.5 microns in diameter or smaller—in locations across the U.S. The researchers identified 245 children who were diagnosed with autism spectrum disorder (ASD) and a control group of 1,522 children without ASD during the time period studied.

Exposure to PM2.5 was significantly associated with autism during pregnancy, but not before or after, the study found. And during the pregnancy, the third trimester specifically was significantly associated with an increased risk. Little association was found between air pollution from larger-sized particles (PM10-2.5) and autism.

From Science Daily: New floor covering can lead to breathing problems in babies

New flooring in the living environment of pregnant women significantly increases the risk of infants to suffer from respiratory diseases in their first year of life. This is the result of a study that demonstrates that exposure to volatile organic compounds in the months before and after birth induces breathing problems in early childhood. The scientists therefore recommend that redecoration should be avoided during pregnancy or in the first year of children’s life.

The observed health risks are caused by increased concentrations of volatile organic compounds (in short: VOCs), such as styrene or ethylbenzene, which escape from new flooring and are then absorbed through the respiratory air. "We therefore do not recommend that laminate, carpet or floor coverings be laid in the homes of pregnant women. Although the concentrations of these volatile chemicals are lower if no adhesive is used when installing the flooring, even then the concentrations are still high enough to significantly increase the risk of infants suffering from respiratory complaints in their first few months," explains Dr. Ulrich Franck from the UFZ. 

Earlier studies from Leipzig had already shown that chemicals from home renovations lead to changes in the immune system of new-born children.... According to our results, exposure to these volatile chemical compounds seems to be more critical in pregnancy than in the first year of a child's life," concludes Dr. Irina Lehmann from the UFZ, who is in charge of the LINA study on lifestyle and environmental factors and their influence on the risk of allergies in newborn babies. An analysis of the data showed that renovations after the birth of a child had a much lower impact on respiratory problems than during pregnancy.

Interesting, but it is currently unknown why this occurs. From Science Daily:

People with blood groups A, B and AB at higher risk of type 2 diabetes than group O

A study of more than 80,000 women has uncovered different risks of developing type 2 diabetes associated with different blood groups, with the biggest difference a 35 percent increased risk of type 2 diabetes found in those with group B, Rhesus factor positive blood compared with the universal donor group O, Rhesus factor negative.

While previous studies have investigated the links between blood group and stroke (finding an increased risk for group AB versus group O), those on blood groups and their link with diabetes have been small and thus underpowered and unable to provide definitive results. In this new research, Fagherazzi and colleagues took data from 82,104 women from the large prospective E3N cohort in France followed between 1990 and 2008. The objective of this study was to evaluate the relationship of ABO blood type (A, B, AB and O), Rhesus factor (positive or negative) and a combination of the two (ABO×Rhesus) with type 2 diabetes (T2D).

The results showed that, compared with women with group O blood, women with group A were 10% more likely to develop T2D, and those with group B 21% more likely (both statistically significant). The AB group was 17% more likely to develop T2D, but this result was not statistically significant. When looking solely at R+ versus R- women, neither group was at increased risk of developing T2D compared with the other.

The authors then combined ABO group and Rhesus group and compared each possible combination with O negative (O-), which is known as the universal donor group because since it contains none of the A. B, or Rhesus antigens, blood from people in this group can be successfully donated to any other group (without rejection).Compared with O- women, the highest increased risk of developing T2D was found in B+ (35% increased risk), followed by AB+ (26%), A- (22%), A+ (17%). The results for O-, B-, and AB- groups were not statistically significant.

Avoid unnecessary ultrasounds because there is an effect on the fetus, even if it's just a temporary effect. Medical associations warn against getting ultrasounds during pregnancy without a real reason. From The Atlantic:

FDA Warning: Stay Away From 'Keepsake' Ultrasounds

The medically unnecessary scans peddled by businesses—often set up in malls and administered by people with no healthcare training—may pose a health risk to both fetus and mother.

Despite repeated warnings by the Food and Drug Administration over the years, commercial ultrasound businesses—often set up in shopping malls and run by untrained technicians—continue to offer their services to expectant parents. And consumers, despite the FDA’s pleas, continue to pay for them, shelling out hundreds of dollars for photos or videos of their developing fetus (and fueling a thriving Etsy niche, where ultrasound images can be turned into ultrasound cufflinks, pillows, cake toppers, and truly unsettling night lights.)

Earlier today, the agency issued the latest of a long line of alerts against non-medical ultrasounds and heartbeat monitors, reminding consumers that “both are prescription devices designed to be used by trained healthcare professionals only when there is a medical need, based on a prescription,” and that “the FDA strongly discourages their use for creating fetal keepsake images and videos.”

Ultrasounds, which use sound waves to produce an image, are considered a safe and valuable diagnostic tool during pregnancy, when they can provide information on the fetus' age, sex, and overall health. But “ultrasound can heat tissues slightly, and in some cases, it can also produce very small bubbles in some tissues,” FDA biomedical engineer Shahram Vaezy said in the alert. Because the long-term effects of the heating are unknown, these gratuitous ultrasounds, which provide no medical information, may pose a small but unecessary risk to both mother and fetus—compounded by the fact that their duration, and the qualifications of the people administering them, aren't subject to regulation.... (Researchers have recently focused on ultrasound as a possible method of male contraception, noting that it dramatically lowers sperm count when applied to the testicles.)

Several medical groups have also come out against commercial ultrasounds over the years, including the American Medical Association, the American College of Obstetricians and Gynecologists, the American College of Radiology, the American Institute of Ultrasound in Medicine, and the American Pregnancy Association.

This was so ridiculous that I couldn't resist - Male idiot Theory! More examples are in the original study published in the BMJ or British Medical Journal (e,g., the man who shot himself in the head with a “spy pen” weapon to show his friend that it was real). Please note: every Christmas the BMJ publishes research whose premises are a bit off kilter. From Science Daily:

Study supports the theory that men are idiots

Sex differences in risk seeking behaviour, emergency hospital admissions, and mortality are well documented. Males are more likely to be admitted to an emergency department after accidental injuries, more likely to be admitted with a sporting injury, and more likely to be involved in a fatal road traffic collision.

However, little is known about sex differences in idiotic risk-taking behaviour. So researchers in north east England decided to test "male idiot theory" (MIT) that many of the differences in risk seeking behaviour may be explained by the observation that men are idiots and idiots do stupid things.

They reviewed data on idiotic behaviours demonstrated by winners of the Darwin Award over a 20 year period (1995 to 2014), noting the sex of the winner. To qualify, nominees must improve the gene pool by eliminating themselves from the human race using astonishingly stupid methods.

Worthy candidates include a man stealing a ride home by hitching a shopping trolley to the back of a train, only to be dragged two miles to his death before the train was able to stop; and the terrorist who posted a letter bomb with insufficient postage stamps and who, on its return, unthinkingly opened his own letter.

Of these 318 cases, 282 Darwin Awards were awarded to males, and just 36 awards given to females. Males thus made up 88.7% of Darwin Award winners, and this sex difference is highly statistically significant, say the authors. This finding is entirely consistent with male idiot theory (MIT) and supports the hypothesis that men are idiots and idiots do stupid things.

However, this study has limitations, add the authors. For example, women may be more likely to nominate men for a Darwin Award or the sex difference may reflect differences in alcohol use between men and women. Despite this, it is puzzling that males are willing to take such unnecessary risks -- simply as a rite of passage, in pursuit of male social esteem, or solely in exchange for "bragging rights," say the authors.

Children spending time outside (more than 14 hours a week) have lower rates of nearsightedness, even if they spend a lot of time reading. From Science Daily:

Scientists study effects of sunlight to reduce number of nearsighted kids

Kids who spend more time outside are less likely to need glasses for nearsightedness – but scientists don’t know why. Researchers are now looking more closely at physical changes in the eye influenced by outdoor light exposure in the hopes of reducing cases of myopia, which affects one-third of the American population.

Despite what many parents may think, kids who spend a lot of time reading or squinting at tiny electronic screens aren't more likely to become nearsighted than kids who don't. However, that risk is only reduced if the child spends plenty of quality time outside. The "outdoor effect" on nearsightedness, or myopia, is a longstanding observation backed by both scientific and anecdotal evidence. It's so compelling that some nations in Asia, which have among the highest myopia rates in the world, have increased the amount of daily outdoor time for children in the hopes of reducing the need for glasses.

But so far, no one has defined exactly what it is about being outside that seems to offer a protective effect against the condition, which causes distant objects to appear blurry.

"Data suggest that a child who is genetically predisposed to myopia are three times less likely to need glasses if they spend more than 14 hours a week outdoors," says optometrist Donald Mutti, OD, PhD, of The Ohio State University College of Optometry. "But we don't really know what makes outdoor time so special. If we knew, we could change how we approach myopia."

Supported by a pilot grant from Ohio State's Center for Clinical and Translational Science (CCTS), Mutti is now focusing his research on the variables he feels have the most potential: invisible ultraviolet B rays (UVB) and vitamin D, and visible bright light and dopamine."Between the ages of five and nine, a child's eye is still growing. Sometimes this growth causes the distance between the lens and retina to lengthen, leading to nearsightedness," explained Mutti. "We think these different types of outdoor light may help preserve the proper shape and length of the eye during that growth period."

UVB light is invisible to the human eye, but triggers several cellular functions in the body, including the production of vitamin D. Vitamin D is thought to support the function of the smooth muscle tissue found around the lens in the eye. This muscle not only helps focus light on the retina, but may also maintain the proper eye shape and length between the lens and the retina, something that can become distorted during the rapid growth of a child's eye.

Some studies, including one by Mutti, show that people with myopia have lower blood levels of vitamin D -- indicating that they have spent less time outdoors, with possible negative effects on the eye..."We don't know if vitamin D is simply a proxy for measuring outdoor time, or if it is actually exerting a biological effect on how the eye works and develops," said Mutti.

There's another part of sunlight that could help prevent myopia: exposure to visible bright light. Even on a cloudy day, visible light outdoors is at least 10 times brighter than the light indoors.When exposed to outdoor light, specialized cells in the retina help control how big or little the pupil dilates to let more or less light in. The cells connect to others that release dopamine -- an important neurotransmitter in the eye and brain. Previous research suggests that dopamine also slows down the growth of the eye, but there isn't technology currently available that can measure dopamine release in the eye directly.

Of course! From Science Magazine:

Guts of obese dogs look similar to those of obese people

Obese people have a less diverse array of bacteria living in their guts than do thin people—and the same holds true for dogs. In a new study, researchers fed seven beagles unrestricted amounts of food for 6 months, during which each dog gained an average of 4.93 kilograms—about 67% of their initial average weight of 7.37 kilograms. The investigators fed another seven beagles controlled food portions, and, as expected, this group did not gain weight.

When the researchers examined the fecal samples collected from both groups after 6 months, they found that the guts of obese beagles contained a smaller diversity of bacteria than those of the other dogs. What’s more, microbes from the phylum Firmicutes were the predominant group in the lean dogs, whereas Gram-negative bacteria called Proteobacteria were prevalent in the obese group, the team reported online this month in the Journal of Veterinary Internal Medicine. The researchers speculate that an abundance of Proteobacteria may lead to an increase in lipopolysaccharide, a major component of the cell wall of Gram-negative bacteria, which has been linked to weight gain in mice. More research is needed to examine what role gut bacteria may play in the development of obesity, however, the authors say.

Think of incense burning as indoor air pollution, with some of the same chemicals and particulates as cigarettes. From Environmental Health Perspectives:

Ritual Risk: Incense Use and Cardiovascular Mortality

Numerous studies have examined exposures to indoor combustion products such as secondhand smoke and emissions from burning of solid fuels. However, only a few have examined incense burning as a potential health threat, even though incense is commonly used for religious and ritual purposes in China, Taiwan, Singapore, India, and Middle Eastern nations.1,2In this issue of EHP, investigators report an association between long-term incense use and increased cardiovascular mortality.1

The study used data from the Singapore Chinese Health Study, which enrolled a cohort of 63,257 Chinese adults aged 45–74 years between 1993 and 1998. The authors identified cardiovascular deaths of cohort members via a nationwide death registry, checking the registry yearly through 31 December 2011.

More than three-quarters of the participants reported currently using incense, and another 13% were former users. Most had used incense daily for at least 20 years, typically keeping it burning intermittently throughout the day. The authors estimated that current long-term incense users had a 12% increased risk of cardiovascular mortality compared with former and never users, including a 19% increased risk for stroke and a 10% increased risk for coronary heart disease.1

Previous studies reported concentrations of volatile organic compounds and particulate matter in incense emissions similar to those in cigarette smoke.3,4 Others showed that long-term exposure to incense smoke increased blood vessel inflammation and affected blood flow in rats.5 In vitro studies have indicated adverse impact to human coronary6 and lung cells.4 

 In contrast with outdoor air pollution, incense exposure may be easier for an individual to avoid, but Yeatts says education will be needed to help people understand the risks of these exposures, similar to educational campaigns about cigarette smoking.Koh published an earlier prospective study that found an association between incense use and upper respiratory cancer.7

Further reasons to try to consume foods and beverages from glass containers and avoid cans and plastic bottles. Note that the BPA caused changes within 2 hours, and that BPA-free alternatives may be no better than BPA. Some researchers are speculating whether the high incidence of hypertension is linked to the prevalence of BPA in our environment. From Medical Xpress:

Cans lined with Bisphenol A may increase blood pressure

Drinking or eating from cans or bottles lined with Bisphenol A (BPA) could raise your blood pressure, according to new research reported in the American Heart Association's journal Hypertension. BPA, a chemical used as an epoxy lining for cans and plastic bottles, is everywhere, and its consumption has been associated with high blood pressure and heart rate variability. Previous studies have shown that BPA can leach into foods and drinks.

"A 5 mm Hg increase in systolic blood pressure by drinking two canned beverages may cause clinically significant problems, particularly in patients with heart disease or hypertension," said Yun-Chul Hong, M.D., Ph.D., study author... "A 20 mm Hg increase in systolic blood pressure doubles the risk of cardiovascular disease."

In this study, researchers conducted a randomized crossover trial recruiting 60 adults, mostly Korean women, over the age of 60 from a local community center. Each trial member visited the study site three times and was randomly provided with soy milk in either glass bottles or cans. Later urine was collected and tested for BPA concentration, blood pressure and heart rate variability two hours after consumption of each beverage.

Urinary BPA concentration increased by up to 1,600 percent after consuming canned beverages compared to after consuming the glass-bottled beverages.. Soy milk was the ideal beverage for the test because it has no known ingredient that elevates blood pressure, researchers said.

UPDATE: The NY Times has a nice write-up of this research with further details:

BPA in Cans and Plastic Bottles Linked to Quick Rise in Blood Pressure

A single instance of increased blood pressure may not be particularly harmful. But the findings suggest that for people who drink from multiple cans or plastic bottles every day, the repeated exposure over time could contribute to hypertension, said Dr. Karin B. Michels, an expert on BPA who was not involved in the new research.

BPA has been used since the 1960s to make countless everyday products like plastic bottles, food containers, contact lenses, and even sippy cups and baby bottles. The chemical can leach into food, and studies show that the vast majority of Americans who are tested have BPA in their urine.

The chemical is an endocrine disrupter that can mimic estrogen. In 2012, the Food and Drug Administration said BPA could no longer be used in baby bottles and children’s drinking cups. Canadian regulators formally declared BPA a toxic substance in 2010 and banned it from all children’s products.

Because of growing consumer concerns, some bottles and packaged food products now carry “BPA free” claims on their labels. However, these products often contain chemically similar alternatives – like bisphenol S. One study in the journal Environmental Health Perspectives found that plastic products advertised as BPA-free still leached chemicals with estrogenic activity – and some of these chemicals were even more potent than BPA.