UV Index very high: Hyderabad fast turning into a "radiation city"

Syed Akbar
Hyderabad: Hyderabad is fast turning into a "radiation city" with harmful ultraviolet (UV) rays hitting the city at "extreme" levels.
UV forecasts for Hyderabad show that the radiation falling down on the city from the sun for most part of the year is on the higher side, which is an indication that all is not well with the ozone layer above and the city's atmosphere.
Hyderabad is bracketed with concrete jungles like Mumbai, Kolkata, Bangalore and Chennai as these cities record "extreme" UV radiation for more than three days a week. However, Delhi appears to be slightly better as the UV radiation levels there are generally "high" to "very high" but rarely "extreme". WHO standards specify that in places where the UV radiation is "extreme", people should better keep indoors and move out only when necessary.
Ultraviolet rays falling on the earth are classified into various categories based on the intensity of the radiation and the harm they cause to human beings and animals. The World Meteorological Organisation, a WHO body, has standardised the UV radiation levels with its "UV Index" which is a simple measure of the UV radiation level at the earth's surface. Hyderabad's UV Index shows a measure of 11, the highest point in the UV scale.
No wonder then that there has been a spurt in skin diseases in Hyderabad may be because of extreme levels of UV radiation. "Most of the cases relate to photo-ageing and skin cancer due to penetration of the rays into the skin. Even if one is in a car the rays can penetrate the glass and impact the skin. The most common skin allergy cases that come to us are related to UV radiation called polymorphic light eruption," senior dermatologist Dr Anup Lahari pointed out.
The values of the UV Index range from zero to 11 and the higher the Index value, the greater the potential for damage to the human body and the less time it takes for harm to occur. On the higher side is the "extreme" and on the lower side is the "very low". In between UV Index is categorised as "low", "medium", "high" and "very high".
The WMO and the World Climate Research Programme as also the India Meteorological Department regularly issue UV forecasts for different cities around the world and in India respectively. The IMD monitors UV levels at its 45 radiation observatories spread across the country.
The UV Index this week is 11 i.e. "extreme" for Hyderabad, Chennai and Mumbai, while it is 8 (very high) for Delhi, 7 (high) for Chandigarh and 10 (very high) for Kolkata. The Index last week was also "extreme" for most part of the week for Hyderabad and other cities except Delhi.
The main reason given for the high intensity of UV radiation in Hyderabad is rapid urbanisation and high levels of pollution.
"As UV radiation can neither be seen nor felt, the UV Index is an important tool to raise awareness of the problem and alert people on a daily basis to take prompt, appropriate and protective action. That Hyderabad has high UV Index is an indication that the ozone layer is not properly filtering the sunlight. If the ozone does its job properly, the harmful radiation are filtered out. The high UV Index shows that the ozone layer has become thin," says Prof OSRU Bhanu Kumar, head of the department of environmental sciences, Andhra University.
Health experts and environmentalists warn that damage from the exposure to the UV rays is cumulative and over a period of time it will lead to serious diseases of the eye, including cataract and macular degeneration.
Consultant radiologist of Care Hospital Dr B Murali suggested that one should go in for massive tree plantation and keep off the sun to the extent possible to avoid UV radiation. "UV radiation exposures are largely preventable. The best protection is achieved by practising a combination of recommended safe behaviours. Limit exposures to sun rays when they are the strongest i.e. between 10 am and 4 pm. Seek shades such as trees or umbrella whenever possible. Use a broad-spectrum sunscreen with sun protection factor of at least 15. Sunglasses can provide 100 per cent protection," he said.
Children are at high risk as on an average they get three times more sun exposure and thus are subject to damaging cumulative effects of UV. It is estimated that 80 per cent of lifetime sun exposure occurs before 18 years of age.
"With the UV rays being equally extreme even in a "garden city" like Bangalore, there has been an increase in eye related problems there. Dr
NM Sudha, senior ophthalmologist from Bangalore, pointed out that ultra violet light is as a causative factor in several eye problems such as cataract, retinal degeneration and surface problems such as pterigyum.