Thanks to Hemlata Rai for her incisive and investigative report on air quality in Kathmandu Valley, ("Gasp!" #137). What I liked about it is that, unlike most people in Nepal, she doesn't just criticise the authorities but also offers them solutions: electric vehicles, an activist judiciary, and also shows them lessons from New Delhi. If India can do it, there is no reason why Nepal can't. After all, our problems are on a smaller scale and much more manageable.

Tek B Thapa,
Kathmandu

. There are indeed numerous causes for Kathmandu's increasingly unhealthy and visually poor air quality. They include extremely adulterated diesel and petrol, brick kilns and the carpet wool dyeing industry. On top of everything else is the increasingly prevalent north Indian sub-continental haze which extends into all Himalayan valleys, including Kathmandu, up to 9-10,000 feet. But the cause is not 20-year-old petrol powered automobiles.

Your investigative report and editorial (#137) both imply that banning 20-year-old cars will help reduce air pollution. There are existing pollution standards that all cars must pass in order to register annually. The simple step of actually enforcing these regulations would alleviate most of the problems often associated with older cars, and eliminating the institutional and retail level fuel adulteration would take care of the rest of these problems. If a car can't be tuned to pass the test, then it should be rebuilt or taken off the road.

We own two European cars, one 37 and the other 45 years old. Both handily pass the emission test every year and do not deserve to be banned from the roads, not to mention be rendered worthless. The 20-year-old vehicle ban is a red herring. The real problems are the shameless adulteration of petrol and diesel with subsidised kerosene, the brick kilns and the dyeing plants.

I respectfully submit that the concerned authorities, if there are any, should turn their attention to enforcing existing emission standards and figuring out a way for the petroleum products industry to make a profit without adulteration. Raising the price of petrol to allow a profit might help, but the real solution is spot checks on fuel quality and huge fines or jail sentences for unscrupulous merchants. May the green groups and the Supreme Court focus on the real problems.

Charles Gay,
Kathmandu

. In Hemlata Rai's otherwise excellent report on air pollution, there is a mistake that needs to be corrected in the interest of accuracy. It is true that benzene is a serious carcinogen, but the direct source of it is not adulterated kerosene. Benzene is added to diesel and petrol to improve the octane value, and is supposed to be eliminated from the emission through catalytic converters. Most cars in Kathmandu don't have proper converters. Additionally, kerosene vapours in the exhaust reduces the ability of the catalytic converters to trap benzene.

Upendra Kumar,
email

. How long do we have to wait before we can start breathing clean air? In my mind there is only one logical way out for Nepal: electric vehicles. As a hydropower-rich nation we should take the lead in the region and the world in moving away from fossil fuels with incentives for electric cars and applying the polluter-pays principle to gas cars. And then, move on to pedestrianise the historic core areas, and the municipality should start planting trees instead of chopping them down like it has done with the stately eucalyptus at Battisputali.

Rabina Dachalica,
Bhaktapur