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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.

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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.

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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.

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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.

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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.

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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.

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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

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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.

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Considering all the antibiotics that the typical sinusitis sufferer takes over the years, reading this article was depressing. One wonders, can the gut microbiome (community of microbes) recover from many rounds of antibiotics and how long does it take? Please note: CD is Crohn's disease, UC is ulcerative colitis, and IBD is inflammatory bowel disease. Dysbiosis means that the community of microbes (microbiome) is out-of-whack. From Medscape:

Antibiotics Associated With Increased Risk of New-onset Crohn's Disease but not Ulcerative Colitis

The objective of this study was to perform a meta-analysis investigating antibiotic exposure as a risk factor for developing inflammatory bowel disease (IBD).A literature search using Medline, Embase, and Cochrane databases was performed to identify studies providing data on the association between antibiotic use and newly diagnosed IBD. 

Conclusions: Exposure to antibiotics appears to increase the odds of being newly diagnosed with CD but not UC. This risk is most marked in children diagnosed with CD.

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Environmental factors have a key role in the pathogenesis of inflammatory bowel disease (IBD)...Furthermore, the incidence of IBD has been increasing worldwide over time. Developing countries have seen an increase in IBD incidence as they have Westernized.

Emerging evidence suggests that certain medications are associated with an increased risk of new-onset IBD. In particular, antibiotics have been linked to the development of both Crohn's disease (CD) and ulcerative colitis (UC).Growing research suggests that the microbiome and its interaction with the mucosal immune system are important in the pathogenesis of IBD.Antibiotics can cause alterations to the microbiome that may potentially contribute to the dysbiosis and dysregulated immune response seen in IBD.

Previous studies have investigated the association of antibiotic exposure with newly diagnosed IBD in both adult and pediatric populations. CD has been more consistently associated with antibiotic use, with some studies demonstrating an increased risk of CD but not UC. It also appears that patients who receive more frequent courses of antibiotics have a higher likelihood of developing IBD.

The results of this meta-analysis suggest that exposure to antibiotics increases the risk of new-onset IBD. When stratifying by type of IBD, antibiotic exposure was associated with an increased risk of developing CD but not UC. We found that the magnitude of risk of new CD is greater for children than for adults. All classes of antibiotics studied, with the exception of penicillins, were associated with new diagnoses of IBD. Interestingly, the types of antibiotics showing the strongest association were fluoroquinolones and metronidazole.

Although it is impossible to draw causal links on the basis of these data, there are some possible implications and explanations for our findings. First, our findings may support the importance of disruptions in the microbiome in the pathogenesis of IBD. The link between antibiotic exposure and new IBD seems biologically plausible. It is known that the microbiome likely has an important role in the pathogenesis of IBD. Studies have shown a decrease in the diversity and stability of both mucosa-associated bacteria and fecal bacteria in patients with CD and UC.For example, the largest cohort microbiome study to date recently found that newly diagnosed CD patients have increased Enterobacteriaceae,Pasteurellaceae, Veillonellaceae, and Fusobacteriaceae, and decreased Erysipelotrichales, Bacteroidales, and Clostridiales.

Antibiotics have been shown to alter the composition of the human gut microbiota by decreasing taxonomic richness and diversity....Although the microbiome may recover to its initial state within days to weeks after antibiotic treatment, some studies have shown a longer-term impact of antibiotics on specific microbial populations that can persist for months to years.

It is unclear as to why antibiotic exposure was associated with new-onset CD and not UC. Studies have suggested a difference in the microbiota between CD and UC patients....Our finding that pediatric populations appear to have an increased association of antibiotic use with new-onset CD compared with adults may reflect the less stable nature of the microbiome earlier in life. During the first 3 years of life, the microbiome appears to undergo marked changes and significant maturation toward an adult-like composition with greater interpersonal variation. It is possible that antibiotics may therefore have a greater impact during childhood when the gut microbiota composition is still developing.

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Another popular view bites the dust.

From the NY Times: Why Antioxidants Don’t Belong in Your Workout

Antioxidant vitamins are enormously popular with people who exercise. The supplements are thought to alleviate muscle damage and amplify the effects of exercise. But recent studies have raised questions about whether antioxidants might be counterproductive for runners and other endurance athletes. And now a cautionary new experiment adds to those doubts by finding that antioxidants may also reduce the benefits of weight training.

 Both aerobic exercise and strength training lead to the production of free radicals, molecules that in concentrated amounts can cause tissue damage. Antioxidants sop up and neutralize free radicals. So, the thinking goes, taking antioxidant should lessen some of the damage and soreness after exercise and allow people to train harder.But recent experiments with endurance athletes have found that consuming large doses of vitamins C and E actually results in a slightly smaller training response. 

So for the new study, which was published online this month in The Journal of Physiology, scientists at the Norwegian School of Sports Sciences in Oslo and other institutions, some of whom previously had studied aerobic exercise and antioxidants, set out to repeat those experiments in a weight room.

They began by recruiting 32 men and women who had at least some experience with weight training. They measured the volunteers’ muscular size and strength.Then they randomly divided them into two groups. Half were asked to start taking two antioxidant vitamin pills each day, one before and one after exercising. The total daily dosage amounted to 1,000 milligrams of Vitamin C and 235 milligrams of Vitamin E, which “is high but not higher than athletes commonly use,” ...The other group did not take any supplements.

All of the volunteers then began the same resistance-training regimen, consisting of four fairly rigorous training sessions each week. As the exercises grew easy, weights were increased, with the aim of pumping up the size and strength of the volunteers’ muscles.The program lasted 10 weeks. 

In general, people’s muscles had increased in size to the same extent, proportionally. The group that had taken the vitamins now had larger muscles. So did the group that had not. But there were subtle but significant differences in their strength gains. Over all, the volunteers who had taken the antioxidants had not added as much strength as the control group. Their muscles were punier, although they had grown in size.

The differences continued beneath the skin, where, as the muscle biopsies showed, the volunteers taking the vitamins had reduced levels of substances known to initiate protein synthesis. Protein synthesis is necessary to repair and strengthen muscles after weight training. So the volunteers taking the vitamins were getting less overall response from their muscles, even though they were following the same exercise program.

Exactly how antioxidant pills change muscles’ reactions to weight training is still unknown. But Dr. Goran and his colleagues speculate that, by reducing the number of free radicals after exercise, the vitamins short-circuit vital physiological processes. In this scenario, free radicals are not harmful molecules but essential messengers that inform cells to start pumping out proteins and other substances needed to improve strength and fitness. Without enough free radicals, you get less overall response to exercise.

The upshot is that whether you lift weights or jog, Dr. Goran would advise “against the use of high-dosages of concentrated antioxidant supplements.”