Wednesday, January 07, 2009

Babies may absorb smoke residue in the home

Calling this "third-hand smoke" may seem clever but it demeans the problem. Nicotine is sticky stuff and is NOT easily removed from the environment and could be ingested in the ways suggested. Whether enough is ingested to have much effect is however the next question

As any parent knows, crawling babies explore the world by touching - and tasting - anything they can get their wet little hands on. If their parents use tobacco, that curiosity may expose babies to what some doctors are calling "thirdhand" smoke - particles and gases given off by cigarettes that cling to walls, clothes and even hair and skin. Up to 90% of the nicotine in cigarette smoke sticks to nearby surfaces, says Georg Matt, a professor at San Diego State University.

Preliminary research by Matt and others suggests the same chemicals that leave a stale cigarette odor on clothes and upholstery also can be swallowed, inhaled or absorbed through the skin of non-smokers. Smoke residue may linger for hours, days or months, depending on the ventilation and the level of contamination. In some cases, contaminants may need to be removed by rigorously cleaning or replacing wallpaper, rugs and drapes, Matt says. Matt cautions that his research needs to be confirmed by other studies. But his work suggests that babies may take in nicotine and other chemicals just by hugging their mothers - even if their mothers never light up next to them.

About 43% of children ages 2 months to 11 years live with a smoker, according to research described in Matt's 2004 study in the journal Tobacco Control. In his small study of 49 infants under 13 months old, Matt found nicotine in the air and dust throughout smokers' homes, even when parents smoked only outside. Tests also found a nicotine byproduct, cotinine, in babies' urine and inside shafts of their hair. As expected, babies whose parents smoked around them had the highest cotinine levels - nearly 50 times higher than the babies of non-smokers, according to the study.

Smokers who tried to shield their infants had only partial success, Matt says. The babies of parents who smoked only outside had cotinine levels seven times higher than in the infants of non-smokers, the study showed.

Adults also may be exposed to significant smoke residue if they rent cars, hotel rooms or apartments that have soaked up years of smoke, Matt says. He worries more about youngsters, however, because they may be exposed day and night for years.

Children also may be at greater risk because they breathe faster than adults and inhale more chemicals, says Jonathan Winickoff, an assistant professor of pediatrics at Harvard Medical School. Crawling babies may take in chemicals through their skin. Though scientists have extensive evidence about the damage caused by secondhand smoke, they know relatively little about the potential risks of thirdhand exposure, says Brett Singer, a scientist at California's Lawrence Berkeley Laboratory. "The million-dollar question is: How dangerous is this?" Singer says. "We can't say for sure this is a health hazard."

Matt agrees that doctors should study children - ideally for 10 or 15 years or more - to see whether low levels of smoke residue worsen asthma or harm the development of a child's lungs.


Keeping a diary can help the body recover from injuries

This sounds like a fairly reasonable study but whether the effect generalized beyond Scottish students is a questioin

Writing a diary may help athletes and people with muscle injuries recover quicker because expressing emotion reduces stress. Writing a diary could help athletes and others with muscle injuries recover more quickly, scientists say. A new study has discovered that sportsmen and women who write about their injuries and associated emotions recover muscle strength three times more quickly than usual. Researchers believe facing up to distress rather than bottling it up reduces stress and inflammation, boosting the body's ability to repair damage.

Study leader Dr Elaine Duncan of Glasgow Caledonian University recruited 46 students aged 19 to 34 who competed in sports including athletics, basketball and football. All had muscle injuries serious enough to prevent them training. Half were asked to write about how they had hurt themselves and how they felt about it. They saw muscle strength improve by nine per cent over the five weeks of the study, compared with three per cent for the others.


Playing outdoors protects young eyes from myopia

The differences reported below do seem to be quite stark and well controlled so the "safety" freaks who try to stop almost all outdoors childhood play may be damaging the vision of those children

The hours spent in front of the PlayStation or at the computer play no role in ruining a child's sight, with Australian researchers finding that being cooped up indoors is what gives children glasses. Children should spend two to three hours a day outside to prevent them becoming short-sighted, says a study by the Australian Research Council Centre of Excellence in Vision Science. A comparison of children of Chinese origin in Australia and Singapore, which has the highest rate of myopia in the world, found the only significant difference was the time spent outdoors.

The study, conducted on the centre's behalf by Australian National University and Sydney University researchers, challenges the prevailing assumption that near work, such as watching television, reading a book or playing computer games, ruins vision. Ian Morgan from the ARC Vision Centre yesterday said exposure to daylight appeared to play a critical role in limiting the growth of the eyeball, which is responsible for myopia or short-sightedness.

Professor Morgan said it had been apparent for a couple of hundred years that more educated people were short-sighted, but the research suggested spending some hours a day outdoors could counteract the myopic effects of study. "Video games are as ineffective as reading on vision," he said. "Computers are pretty neutral, watching television doesn't seem to affect vision. The only difference we could find is the amount of time spent outdoors. "As you are involved in intensive education through to studying at university, you ought to be conscious of this well into your mid-20s."

The research says about 30 per cent of six-year-olds in Singapore are short-sighted enough to need glasses, compared with only 3 per cent of Chinese-Australians. Both groups spend the same amount of time studying, playing video games, watching television and reading books. But Singapore children spend an average 30 minutes a day outdoors compared with two hours in Australia.

Professor Morgan said similar trends were seen in India, with 5per cent of rural-dwelling Indians being short-sighted compared with 10 per cent of their urban cousins and 65 per cent of those living in Singapore.

Myopia is increasing in urban areas around the world, and is described as an epidemic in parts of east Asia, with Singapore the world capital. Australia has a level of myopia more commonly found in the Third World, with only 0.8 per cent of six-year-olds of European origin being short-sighted. They spend on average three hours a day outdoors.


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