Hyderabad: Hydrogen sulphide emissions from untreated sewage and carbon emissions from dump yards are the main reasons for carbon deposits accumulating on electric wires and causing trains to malfunction. A senior environmental scientist at the Pollution Control Board explained, "Hydrogen sulphide is an issue at major sewage points; it interacts with the copper in the wires turning it into copper sulphide and causing the deterioration. The electric insulation has to be increased or the maintenance has to be taken up more frequently to undo the damage."
Officers of the Pollution Control Board have visited the Uppal depot to check out the situation but there has not been any response from them. When this newspaper contacted PCB officials, they refused to comment, stating that they will have to check exactly what the problem is.
The Delhi Metro Rail suffered from the same problem as pollution levels in the capital are very high. To overcome the problem, the copper split pins in the electric wires of metro trains were changed to stainless steel pins.
Delhi Metro Rail replaced a total of 9,532 copper pins with stainless steel pins to deal with the problem of sudden stopping of the trains and frequent breakdowns due to the carbon deposits.
With Hyderabad Metro Rail the problem is only at the Uppal depot because it is close to the dumping yard and sewage depot. The danger of these gases to the health of people living and working in the surrounding area can be very severe.
Dr Mehboob Khan, senior professor and superintendent of Government Chest Hospital, explained the ill effects of these harmful emissions on the human body.
"The presence of these gases like sulphide, hydrogen and other oxides in the air decreases the supply of oxygen in the blood. There will be symptoms like headaches, tremors, and breathlessness and long term effects can involve deterioration of the organs. The circulatory system through which oxygen is carried to different parts of the body is badly affected due to which the lungs have to overwork. Apart from that, there is constant bad odour which can cause severe irritation.”