Killing ‘sense of smell’

While the country folk can detect contaminant in food (that makes bad smell) in lower levels, city dwellers are even more resistant. The 20 Million inhabitants of the Mexico City are probably going to lose their ‘sense of smell’. Reason: air pollution.

It’s even difficult to see the snow-covered peaks of the surrounding mountains through the smog (Smoke + fog). Smog generates from a chemical reaction, formation of which is accelerated during a sunny day. In the presence of sunlight, oxygen (O₂), volatile organic compounds (VOCs) and nitrogen oxides (NOx) often create smog that results in high concentration of ground-level ozone and air borne particles.

The atmospheric ozone layer protects Earth from Sun’s ultraviolet (UV) rays, but at ground level it is a major element of air pollution. It can damage the respiratory tract and can cause other health problems. Mexico City’s ozone level often exceeds WHO’s (World Health Organization) standards. Currently WHO’s air quality guideline value for ozone is 100 µg/m3 (micrograms per cubic meter) for a daily maximum 8-hour mean (WHO, 2005).

The surrounding mountains trap the air from leaving the city and fresh air input, but the number of new cars lining up the streets each year is also a major reason for the overwhelming air pollution.

Source: Reuters       More: air pollution