Friday, December 13, 2013
How traffic fumes can be deadly - even at 'safe' levels: Living near a busy road can increase risk of premature death by 7%
A tiny and hence totally insignificant effect
Living near busy roads could put men at higher risk of premature death – even when air pollution levels are rated as ‘safe’, claim researchers. A major study found exposure to traffic pollutants can push up the risk of dying by seven per cent, compared with living in quieter neighbourhoods.
There is mounting evidence of the health dangers of pollution, which is already known to play a part in asthma attacks, heart attacks and strokes.
Microscopic particles largely generated by diesel exhausts have been shown to cause lung damage and harmful changes in blood vessels and clotting.
But the latest study adds to research showing problems occur at levels well below those stipulated in current European Union (EU) air-quality directives.
The new research examined two decades of data from 22 studies involving over 367,000 residents of large cities in 13 European countries.
Researchers looked at the impact of prolonged exposure to tiny particles of soot or dust found in traffic fumes and industrial emissions, fine-particle matter known as PM 2.5.
They estimate that for every increase of 5 micrograms per cubic metre (5 µg/m3) in annual exposure to PM 2.5, the risk of dying from rises by seven per cent.
The risk of death increased only in men, not in women.
Study leader Dr Rob Beelen from Utrecht University in the Netherlands, said ‘A difference of 5 µg/m3 can be found between a location at a busy urban road and at a location not influenced by traffic.
‘Our findings support health impact assessments of fine particles in Europe which were previously based almost entirely on North American studies.’
In the study air pollution concentrations of nitrogen oxides and particulate matter were estimated at home addresses of participants, along with traffic load on nearly major roads.
Traffic density on the nearest road and total traffic load on all major roads within 100m of the residence were also recorded.
Among the participants, 29,076 died from natural causes during the average 14 years of follow up, says a report in The Lancet medical journal (must credit).
The results showed that long-term exposure to fine particles with a diameter of less than 2.5 micrometres (PM2.5) posed the greatest threat to health even within concentration ranges well below the limits in current European legislation.
The link between prolonged exposure to PM2.5 and premature death was significant even after taking into account factors such as smoking, obesity and activity levels.
Dr Beelen said ‘Our findings suggest that significant adverse health effects occur even at PM2.5 concentrations well below the EU annual average air-quality limit value of 25 µg/m3.
‘The WHO air-quality guideline is 10 µg/m3 and our findings support the idea that significant health benefits can be achieved by moving towards this target.’
Previous research found pregnant women exposed to ‘safe’ levels of air pollution have a higher risk of giving birth to small babies.
Jeremy Langrish and Nicholas Mills from the University of Edinburgh, writing a commentary in the journal, said ‘Despite major improvements in air quality in the past 50 years, the data from Beelen and colleagues’ report draw attention to the continuing effects of air pollution on health.
‘These data, along with the findings from other large cohort studies, suggest that further public and environmental health policy interventions are necessary and have the potential to reduce morbidity and mortality across Europe.
‘Movement towards more stringent guidelines, as recommended by WHO, should be an urgent priority.’
Prof Frank Kelly, Professor of Environmental Health at King’s College London, said ‘This study enhances an increasing scientific evidence base that PM2.5 poses a danger to health at concentrations below current EU limit values and supports the ongoing WHO review of European air quality policies.
‘Results such as these, plus recently published data claiming combustion emissions in the US account for 200,000 premature deaths per year, show that policy measures have enormous potential to create a cleaner and healthier environment.
‘Such action is particularly urgent in cities where concentrations of pollutants routinely breach current EU limit values, let alone the more stringent and health-based WHO guidelines - such as London.’
Why diet cola could be making you FATTER and WRINKLIER: Low-calorie drink could be to blame for spare tyre and withered skin
Diet colas have long been regarded as the dieter's friend - but one-calorie fizzy drinks may actually be the reason you can't shift that stubborn spare tyre.
Some health experts now believe the chemicals in the drink could actually be causing your body to lay down fat deposits around your middle - dubbed 'diet cola belly' - reports Get The Gloss.
And that's not all: some experts also believe diet cola’s mix of carbonated water, colourings and sweeteners such as aspartame and acesulfame K could also speed up the ageing process, and have disastrous health consequences.
Hoards of nutritionists and scientists now claim diet cola’s image as a 'healthy' alternative to the nine-teaspoons-of sugar, regular variety of the fizzy drink is wholly misplaced.
The fructose, artificial sweeteners, and sugar alcohols (another type of low-calorie sweetener) present in diet colas can all interfere with natural gut bacteria, according to Amanda Payne of Switzerland’s Institute of Food, Nutrition and Health which published a paper in the journal Obesity Reviews.
This messes up your metabolism and disrupts the body’s way of signaling to you that you’re full and satisfied.
As a consequence, the body pumps out insulin, the hormone that controls sugar levels and fat storage, so that you lay down what Toribio-Mateas calls 'diet cola belly in the form of more fat around the midriff' - just where you wanted to shed fat.
In addition to this: 'The fake sugars in the drink are hundreds of times sweeter than sugar and trick your brain into thinking real sugar is on the way,' says Toribio-Mateas. 'When the calories don’t arrive, it triggers a cascading effect that interferes with hunger signals, blood sugar levels and satiety.'
Amanda Griggs, director of health and nutrition at the Balance Clinic in London, says: 'phosphoric acid, the ingredient that gives diet cola its appealing tangy taste and the tingle you get when it is swallowed, can cause a host of problems'.
According to one, study, published in a 2010 issue of the FASEB Journal, it can even accelerate the ageing process.
It found that the excessive phosphate levels found in sodas caused lab rats to die a full five weeks earlier than the rats whose diets had more normal phosphate levels.
The excessive phosphate levels found in sodas caused lab rats to die a full five weeks earlier than the rats whose diets had more normal phosphate levels
Phosphoric acid has also been linked to lower bone density in some studies, including a discussion in the American Journal of Clinical Nutrition.
In experiments at Harvard University, the mineral was found to make skin and muscles wither and to damage the heart and kidneys over time.
However, according to the Center for Science in the Public Interest (CSPI), a consumer watchdog group not affiliated with the food industry, only a small fraction of the phosphate in diets comes from additives in soft drinks. Most comes from meat and dairy products.
Sian Porter, spokesperson for the British Dietetic Association says diet colas may lack sugar, but the acidic nature of artificially sweetened fizzy varieties means they still attack tooth enamel.
'It’s not just the sugary drinks that are causing teeth problems,' says Porter. 'Sugar raises the risk of decay, but diet drinks are equally acidic and can cause erosion in the same way.'
It has also been shown to raise the risk of type 2 diabetes and high blood pressure by some researchers. To add to the dire news for diet cola fans, results of a ten-year study found a link with cardiovascular disease among those who drank it every day; cola drinkers were found to be 43 per cent more likely to suffer a stroke or heart attack during a ten-year period than those who abstained.
Other studies have shown that the phosphorus released from phosphoric acid in just two fizzy drinks a week can cause calcium to be leached from bones, raising the risk of osteoporosis.
Cola (both diet and regular varieties) seems particularly damaging to the skeleton. Typically, a can of diet cola contains 44-62mg of phosphoric acid - more than in many other soft drinks - and researchers at Tufts University in Boston showed that women who regularly drank three or more cans a day had four per cent lower bone mineral density in their hips compared to those who preferred other soft drinks.
Posted by jonjayray at 12:26 AM