Wednesday, November 09, 2011

Cities not so bad for you

It's an age old belief that cities are bad for you and city-dwelling epidemiologists still regularly produce "proof" of it. So the findings below are rather iconoclastic

According to scientists, carbon monoxide (CO), a tasteless, colorless and odorless gas, is not only a danger to the environment but also highly toxic to human beings. Found in the exhaust of vehicles and generators, CO has been dubbed the "silent killer" because excessive inhalation is lethal, poisoning the nervous system and heart.

Now, in a surprising twist, Prof. Itzhak Schnell of Tel Aviv University's Department of Geography and the Human Environment has discovered that low levels of the poisonous gas can have a narcotic effect that helps citydwellers cope with other harmful environmental factors of an urban environment, such as off-the-chart noise levels. This finding indicates that CO, in small doses, is a boon to the well-being of urbanites, better equipping them to deal with environmental stress.

The research has been published in the journal Environmental Monitoring and Assessment.

Gas combats noise pollution

The discovery was made in the context of a wider project designed to study the impact of environmental stressors on the human body. Most environmental observation stations, explains Prof. Schnell, are located outside stressful city centers, where pollutants such as vehicular and human traffic are significantly decreased, resulting in distorted data.

Instead, Prof. Schnell and his fellow researchers wanted to measure how people living in an urban environment confronted stressors in their daily lives. They asked 36 healthy individuals between the ages of 20 to 40 to spend two days in Tel Aviv, Israel's busiest city. The test subjects travelled various routes to sites such as busy streets, restaurants, malls and markets, by public and private transportation or by foot. Researchers monitored the impact of four different environmental stressors: thermal load (heat and cold), noise pollution, carbon monoxide levels, and social load (the impact of crowds).

Participants reported to what extent their experiences were stressful, and their input was corroborated with data taken from sensors that measured heart rate and pollutant levels. Noise pollution emerged as the most significant cause of stress.

The most surprising find of the study, says Prof. Schnell, was in looking at levels of CO that the participants inhaled during their time in the city. Not only were the levels much lower than the researchers predicted — approximately 1-15 parts per million every half hour — but the presence of the gas appeared to have a narcotic effect on the participants, counteracting the stress caused by noise and crowd density.

Turn down the volume

The results showed that living in a major city might not have as negative a health impact as the researchers were expecting. Though participants exhibited rising stress levels throughout the day, CO had a mitigating influence, and extended exposure to the chemical had no lasting effects.

The study's next step is to investigate how environmental loads impact the more vulnerable segments of the population, such as infants, the elderly, and those with medical conditions such as asthma. "We would be able to tell more accurately under what conditions vulnerable people shouldn't go out, and more importantly, identify areas that are still safe, helping to increase freedom of movement," notes Prof. Schnell.

But for now, urban dwellers can all contribute to making their environment a less stressful one by turning down the noise, he suggests. The findings indicate that most of the noise in an urban landscape is generated by human activity, and if individuals made an effort to reduce the noise they were making, they could help to reduce the environmental load placed on their neighbors.


There's no pleasing the food fusspots

I'VE given up. Not given up on life, but given up on having dinner parties and inviting people to share a meal at home.

Long ago I used to enjoy spending all day in the kitchen cooking up a storm for friends, with my Women's Weekly Dinner Party cookbooks as a guide. I had a reputation among some as being a good cook. The pictures made it easy. However, competing in today's world with MasterChefs all over the place, I'm not sure I could be in their league.

I slowly started to be less enthusiastic when reciprocal invitations became scarce and I had less time, so I decided to resort to simple barbecues. That has worked for a while with some gourmet twists added, but sadly now that too is coming to an end.

Why? Not because I can't be bothered or don't want to do it. It's because there are too many people out there with high and mighty expectations when they go to someone else's place to eat, who would like me to cater for their self-proclaimed illness or the diet they started this afternoon.

There are of course the real vegetarians, the vegans and those who don't eat this or that for various ethnic or genuine medical reasons.

That's fair enough, you might say, but then there are the other ones with the self-diagnosed illnesses or allergies or sensitivities to a variety of foods.

There are health fanatics who were told 20 years ago not to eat red meat by some guru in order to improve their performance in a triathlon. Come on mate, I've known you for 15 years and never seen you do anything near to a triathlon yet. It's not working, trust me, and it's pointless in any case.

I have people requesting that they be served no preservatives, no coriander, no melted cheese, no vegetables, no rice, no garlic, no dairy and various other herbs and spices.

Then there are the genuine people who have been diagnosed with a genuine food problem who say nothing and eat what they can happily. These I thank for making my life easier. However eliminating all these foods doesn't leave me a lot to work with, and when I peruse my recipe books, I can't find much that will satisfy them all without creating several different meals, which I simply refuse to do.

So let it be said that if you come to visit, please bring your own picnic basket, full of your favourite goodies or impossible health foods and we'll all be happy.


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