Get grime-free lungs

A new study has found that for all the hype about London's congestion and pollution problems, our daily habits may do more to affect the level of pollutants we inhale. And by changing these habits, we can dramatically reduce our exposure to particle pollution.

Dr Roy Colvile, a senior lecturer in air quality management at Imperial College London recently carried out research on the fine airborne particles - known as PM10 - that bombard us daily, and which are small enough to enter the respiratory tract.

Many of the particles in London's air are tiny droplets of sulphuric acid, nitric acid, and black smoke generated by diesel exhaust, composed mainly of carbon. Buses and taxis are not only to blame, however - we generate plenty of indoor particles ourselves when we smoke, cook and use aerosol sprays.

The average adult typically inhales five trillion particles daily. We might cough or get itchy eyes when exposed to high pollution levels, but it's the sensitive who are at greater risk, including the very young or elderly, those with heart conditions or lung diseases, including asthma, bronchitis and emphysema. Long-term particle pollution has been linked to the rise in skin and breathing allergies.

According to a Department for Environment study, cutting long-term exposure to fine particles by half could increase life expectancy by between one and 11 months.

Dr Colvile followed one Londoner, 28-year old insurance broker Jim Good, who lives in the West End and commutes to the City, to see what he typically inhales in a day. Jim is single, lives alone and has no allergies or respiratory problems.

7.20am: Jim gets up, showers, sprays on deodorant and aftershave and gets dressed.

"The shower helps clean the air in the bathroom, but spraying aftershave and deodorant instantly recharges it with particles and damaging hydrocarbons," says Dr Colvile. "Using a dab-on cologne and roll-on deodorant would improve the air quality by 96 per cent."

7.40am: Jim burns his toast and sets the smoke alarm off. In the next 15 minutes he inhales more carbon than he would during an hour-long drive in heavy traffic.

"Jim should keep an eye on his toast. Setting off his smoke alarm means he is exposing himself to worse indoor pollution levels than current UK and EU regulations allow on congested main roads."

8.00am: Jim gets the Tube to work. "Using the Underground protects Jim from the harmful diesel particles he'd inhale if he'd taken the bus," says Dr Colvile. "However, the total number of particles is greater on the Tube because of emissions from moving train wheels in the enclosed space. The earlier the Tube Jim gets, the better, as less dust has been stirred up."

8.20am: He has a 10-minute walk from the Tube station along a main road, and crosses at a busy junction to reach his office.

"Jim could take an extra few minutes diverting along one of many quiet back streets. Busy junctions are best avoided, as some of the highest concentrations of fine particles are at signal-controlled crossings, where pedestrians must wait. Pedestrian islands are worst when the wind blows along the road, bringing with it fumes from the queue of traffic.

"He could snatch a minute of slightly cleaner air just by standing away from the kerb and breathing through his nose rather than his mouth, since particle concentrations can double at distances of up to a metre from heavy traffic."`

8.30am: Jim arrives at work and spends most of his working day in an air-conditioned office.

"If the air-conditioning unit is badly designed, this will affect Jim's air quality," says Dr Colvile. "Good positioning of ventilation intakes away from major roads is a highly effective way of controlling the emissions that enter."

1pm: He walks through a nearby park to a café, where he grabs a sandwich before heading back to his desk.

"A walk through the park gives Jim the cleanest air he breathes all day, except on days when the wind from the east brings polluted air to London from Europe."

6.30pm: Jim goes for a drink in a high-street pub near work.

"As a non-smoker, Jim would inhale cleaner air if he chose a pub in a quiet back street, preferably one with a no-smoking area. This would cut particles inhaled by 52 per cent."

8.30pm: Jim grabs a snack and hails a cab home. "Jim inhales fewer particles than if the taxi was crawling in the rushhour." says Dr Colvile. "The cabby's skill in finding back-street short-cuts also gives Jim cleaner air to inhale than if it stuck to the main roads."

11.20pm: Jim's head hits the pillow. His basement flat is by a busy road in central London.

"Closing windows can delay pollution getting inside, but PM10 particles are fine enough to pass around door and window frames. However, if Jim follows all this advice he could cut the number of particles he inhales daily by about 40 per cent."

For information on air pollution, visit www.airquality.co.uk or freephone 0800 55 66 77.