By Syed Akbar
Hyderabad, May 17: Hyderabad sits on carbon monoxide poisoning, a highly
dangerous gas that was once used by kings to execute people.
The average peak level of carbon monoxide or simply CO in the city
atmosphere for the months of January, February, March and April was 18 mg
per cubic metre per hour as against the standard level of 4 mg/cm and
permissible level of 12 mg/cm.
Worse is the case with high traffic areas like Panjagutta where the peak CO
level for the first four months of this year was 26 mg/cm, according to AP
Pollution Control Board ambient air quality studies. The recordings were as
high as 23 mg/cm in Paradise and Charminar and as low as nine mg/cm in
green areas like Nehru Zoological Park and Kasu Brahmananda Reddy
National Park.
City doctors link high incidence of breathing-related problems, nausea and
convulsions among Hyderabadis to constant exposure to vehicular CO
emissions. Carbon monoxide is a highly poisonous gas known to man as
early as 300 years before the birth of Christ and it has emerged as the
single
largest cause of accidentally poisoning among Americans. Increasing number
of vehicles and frequent traffic snarls have turned Hyderabad as one of the
few cities in the country with high CO exposure rates.
"Carbon monoxide can lead to respiratory chronic obstructive pulmonary
disease and allergic bronchitis. It can even lead to death in case of heavy
exposures. At low levels, CO leads to reduced oxygenation which may cause
forgetfulness, fatigue and insomnia. We have been receiving many such cases
of late," says Dr A Raghu, consultant physician at Apollo DRDO Hospital.
This gas has the tendency to freely mix with the blood stream leading to the
formation of carboxyl haemoglobin.
The danger from this gas can be gauged from the fact that haemoglobin
prefers CO to oxygen. The haemoglobin molecule likes to take 200 times
more CO than oxygen, he points out adding that the high levels of CO
concentration in Hyderabad atmosphere will prove disastrous to the health of
the people in the long run.
Though 2.5 per cent carboxyl haemoglobin (at a CO limit of 30 mg/cm for
one hour) is recognised as definitely harmful to health, experts around the
world have now set a standard limit of one per cent carboxyl haemoglobin
(12 mg/cm for one hour). This means in Hyderabad the peak CO level is
more than twice the standard limit.
Senior pulmonologist Dr Pradyut Waghray attributes the high levels of CO in
Hyderabad to fumes from industries and exhaust from diesel vehicles.
"Respiratory cells get affected by carbon monoxide. It also hits RBCs and
reduces oxygen carrying capacity of the blood," he says adding that constant
exposure leads to chronic persistent respiratory asthma.