Tuesday, April 14, 2015

Smokeless tobacco also poses health risks, researchers say

Researchers found carcinogens from smokeless
tobacco products in household dust.
Photo by Uffe_Johansson 
Secondhand exposure to tobacco may be possible even when no cigarette smoke is involved, according to a new study.

An analysis of dust samples from six homes with smokeless tobacco users shows that the dust there contains more tobacco-specific carcinogens and alkaloids than dust from non-tobacco-using homes, putting household members, especially children, at risk of indirect exposure

Scientists have long known that cigarette smoke is carcinogenic, whether inhaled by the user, by others as secondhand smoke, or brought into the home on clothing as thirdhand smoke.

But they didn’t know whether indirect exposures could arise with smokeless tobacco products, such as chewing tobacco or moist snuff.

Todd P. Whitehead of the University of California, Berkeley, School of Public Health and his colleagues wondered whether smokeless tobacco use at home might taint household dust.

They were already collecting dust samples from homes as part of the California Childhood Leukemia Study, which among other things explores how environmental exposures to contaminants such as cigarette smoke could influence leukemia risks.

Of the households they surveyed and analyzed, six told the researchers that they had users only of smokeless tobacco, six had users only of cigarettes, and 20 had no tobacco users.

Using liquid chromatography-tandem mass spectrometry, researchers analyzed dust samples from these homes for five nitrosamines that are found only in tobacco, as well as five tobacco-only alkaloids such as myosmine. The team also used gas chromatography-mass spectrometry to measure nicotine, the best-known tobacco alkaloid, which is addictive.

The team wanted to distinguish smokeless-tobacco contamination from cigarette-smoke contamination, so they calculated the ratio of myosmine to nicotine. In unburned tobacco, myosmine content is less than 0.5% of the nicotine content. But as tobacco burns, myosmine is produced, increasing the ratio to roughly 7% in tobacco smoke.

Levels of two key carcinogenic nitrosamines—N′-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)—were roughly five and seven times as high, respectively, in the dust of smokeless-tobacco households as in samples from tobacco-free households.

Moreover, the median myosmine-nicotine ratio was 1.8% in smokeless-tobacco households versus 7.7% in cigarette-user households, confirming that contamination in the smokeless-tobacco homes came primarily from smokeless tobacco.

Whitehead warns that the researchers don’t yet know how much of a risk this dust contamination might pose, or how the smokeless tobacco got into the dust.

But the findings suggest that household members who don’t use smokeless tobacco could be exposed to its known carcinogens.

Young children, who often play on the ground and put their hands in their mouths, can accidentally ingest dust and may be especially vulnerable to exposure, he says.

The contamination could come from activities such as opening a package or dropping small amounts on the floor during use, Whitehead says, which could lead to simple strategies for reducing the risk of contamination.

Hugo Destaillats, an environmental chemist at Lawrence Livermore National Laboratory who wasn’t involved with the work, calls the findings an interesting first step.

The sample size was small, note both Whitehead and Destaillats, and the study didn’t directly measure anyone’s exposures.

Additional research, they suggest, could focus on the amount of tobacco-related compounds that young kids ingest when they live with someone who uses smokeless tobacco, and the resulting health risks. And Destaillats suggests doing future studies to see how dust contamination might vary in other geographical areas.

Source: American Chemical Society. This article has been edited for length.

Airborne dust and poor indoor air quality pose health risks to young and old alike. AllerAir's air purifiers with activated carbon and HEPA filter out harmful chemicals, fumes, particles and biological contaminants around the clock, helping to provide cleaner and more breathable air. For more information and free consultation, contact AllerAir and write to info@allerair.com.

Thursday, April 09, 2015

Weed killer linked to chronic illness

Toxic chemicals used in farming may contaminate our
food, water and air, experts say.
The bestselling herbicide in Canada and the world, glyphosate was once promoted as safe enough to drink. But some critics are raising renewed alarm.

One of them is Thierry Vrain, a plant pathologist and former head of biotechnology with Agriculture Canada, who says there is no safe intake level for this toxic chemical, which appears to be linked to a rising tide of chronic illnesses.

Indeed, the World Health Organization's International Agency for Research on Cancer has just declared glyphosate a "probable carcinogen."

Farmers have used glyphosate to weed Ontario fields since 1978. But the introduction of genetically modified (GM) crops in 1997 - most of them designed to be glyphosate-tolerant - was a game changer. Farmers could now raze weeds with a single blanket spray of glyphosate without killing their crops.

Though industry promised GM crops would drive down pesticide application, glyphosate use has risen dramatically, by some 76 per cent between 2003 and 2008 in Ontario.

Farmers are increasingly using the herbicide as a desiccant (dryer) on both GM and conventional plants, making harvesting easier or moving up a harvest threatened by bad weather.

It's increasingly difficult to avoid the most popular herbicide on earth. A recent study of U.S. honey found 59 per cent of samples contained glyphosate.

Though a safe glyphosate level in honey hasn't been determined, recent research suggests the current level of glyphosate exposure in general may constitute a health threat to the population.

You might think organic crops would be free of this chemical, but glyphosate has recently been discovered in samples of air and water, so all food may now be tainted.

Glyphosate was first thought to pose little threat because neither human nor animal cells have shikimate pathways, a metabolic route used by plants and bacteria.

Glyphosate does its deadly work by binding to the metal atoms of enzymes in the plant's pathways, preventing them from producing critical amino acids. Without those, the plant dies.

New discoveries about the human microbiome - including the 100 trillion bacteria in the human gut - are starting to reveal the critical role microorganisms play in promoting human health.

Don Huber, professor emeritus of plant pathology at Purdue University, says that just as it attacks plants, glyphosate can demobilize the bacteria on which humans and animals depend.

But Joe Schwarcz, director of the Office for Science & Society at McGill University, says the theories need to be proven under proper laboratory conditions before they should be believed.

Antibiotic threat

Monsanto patented the chemical as an antibiotic in 2010, a tacit acknowledgement of its effectiveness in killing microbes, though the pesticide industry maintains it's applied to fields in concentrations too low to produce any serious antimicrobial effects in the animals, including us, consuming those crops. Schwarcz insists the antibiotic effect is "absolutely trivial."

But Huber argues that increasing miscarriages, birth defects and chronic botulism in cattle, sheep and pigs are signs of glyphosate's strong antibiotic activity against beneficial organisms.

Backing up Huber, Vrain points to research from 2013 showing that, at a concentration of just one part per million, glyphosate killed all the beneficial bacteria in the guts of poultry. Only salmonella and clostridium survived - pathogens blamed for farm animal illness.

In the meantime, a recently published study by Nancy Swanson virtually twinned increasing rates of glyphosate use with rising incidence of a host of chronic diseases. They include liver, kidney and bladder cancers; Crohn's and celiac disease; stroke, diabetes and autism, among others.

New GM seeds resistant to glyphosate, as well as 2,4-D, are expected to start rolling out across Canada this year. The new seeds will help farmers battle glyphosate-resistant weeds.

AllerAir air purifiers contain carbon
and HEPA filters to provide cleaner air.
While Vrain admits that biotechnology has been transformative for the just over 2 per cent of Canadians who farm, "One hundred per cent of people eat," he says.

Source: Now Toronto. This article has been edited for length.

Concerned about chemical exposure at home or at work? AllerAir's air purifiers pack a 1-2 punch against airborne contaminants, including chemicals, odors, fumes, particles, allergens, bacteria, viruses, mold and more. 
For a free consultation, contact AllerAir by calling 1-888-852-8247 or e-mailing info@allerair.com.

Tuesday, April 07, 2015

Air pollution slows brain development: study

Air pollution takes a double toll on babies' brains

Studies have tied air pollution to a wide range
of problems in children.
A common pollutant in vehicle exhaust, power plant emissions and cigarette smoke can shrink white matter in fetal brains and cause developmental damage during the toddler years, a new study suggests.

In 40 children examined by researchers, prenatal exposure to polycyclic aromatic hydrocarbons was correlated with reduced white matter on the left side of children's brains during their early childhood.

Those physical changes in the brain's internal wiring also were correlated with slower cognitive processing and with symptoms of attention deficit and hyperactivity, according to the study published in the journal JAMA Psychiatry.

“They tend to be fidgety and hyperactive and very impulsive, so they leap before they look,” said Dr. Bradley Peterson, director of the Institute for the Developing Mind at Children's Hospital Los Angeles and the lead author of the report.

The researchers had previously tied behavioral and cognitive problems to eight common types of these pollutants, which are a product of incomplete combustion of organic materials.

The new study now suggests those problems have a biological root in the altered architecture of the brain.

The research involved 655 New York City women of Dominican and African American descent who gave birth between 1997 and 2006.

During late pregnancy, the women carried detector backpacks that measured exposure to PAHs over 48 hours. Their children later were tested for exposure and underwent several rounds of cognitive and behavioral testing.

For the JAMA Psychiatry study, Peterson and his colleagues selected a representative sample from the original study group: 20 children whose own PAH readings were below the median and 20 whose PAH levels were above it.

All the children were about 8 years old when they underwent magnetic resonance imagery scans.

Those scans showed that white matter was significantly reduced from normal volumes throughout the left hemisphere, an area that controls language and cognition, among other higher functions.

In fact, the higher their prenatal exposure to PAH was, the more white matter was reduced and the more acute the behavioral and developmental problems were, the study found.

Scientists don’t know why the left side seemed to be affected more, but they suspect the compounds interfere with an early biochemical process that helps the fetal brain divide into slightly asymmetrical hemispheres.

The damage, however, is not isolated to prenatal stages, or to the left hemisphere. Postnatal PAH exposure, measured at age 5, correlated with diminished white matter in areas of the prefrontal cortex of both hemispheres, the study found.

“It’s a double hit,” Peterson said. “They have the abnormality from prenatal life throughout the left hemisphere and then on top of that they have this bilateral frontal hit from exposures around age 5.”

The 40 children were from nonsmoking homes and had little or no exposure to lead or insecticides that likewise have been linked to developmental and behavioral problems, according to the study. All were right-handed.

Although it remains possible that other pollutants could be affecting the results, the researchers said their sampling methods eliminated the major contenders, helping to isolate the effects of the PAH compounds.

Numerous studies have linked air pollution — especially particulate matter — to respiratory and cardiac problems. But over the last decade, researchers have accumulated more evidence that particles and other types of airborne pollution can affect brain development.

A 2012 study using a database of 19,000 nurses found greater cognitive decline among older women exposed to high levels of particulate matter.

A 2011 Boston study involving 680 men showed similar results. A series of studies involving children in Mexico City linked air pollution with the brain inflammation that is typical of diseases such as multiple sclerosis.

“It is worrisome,” Peterson said of the latest findings. “California has gone a long way toward improving and cleaning up the air, but there’s a long way to go. Future generations depend on it.”

Source: LA Times

Are you concerned about air pollution where you live or work? AllerAir has designed a wide range of powerful air purifiers with activated carbon and HEPA air filters that remove airborne chemicals, particles and other contaminants. Contact AllerAir for more information and a free consultation. Call 1-888-852-8247 or write to sales@allerair.com.