The rising level of motor fuel-related pollution in the country has prompted the government to set January 2008 as the new deadline for Pakistan's four oil refineries to switch over from Euro-I (low quality diesel) to Euro-II which has a fairly smaller sulphur content.
According to a Recorder Report, the sulphur content of Euro-II diesel is 2500 ppm (0.25 percent) against Euro-I's 10,000 ppm. The petroleum ministry has issued a fresh circular to the refineries to make arrangements for the switch-over within the stipulated timeframe. The target date set by the government earlier was July 2006, which has been extended on the industry's plea that the period allowed for conducting feasibility studies was not sufficient. The government is now actively pursuing the case to ensure compliance with the fresh deadline.
While the developed world has long switched over to cleaner and more efficient fuels for combating environmental pollution, we are still at the planning stage, even though the environmental degradation is proceeding apace. It has been scientifically established that vehicle emissions result in concentration of such dangerous pollutants as carbon monoxide, oxides of nitrogen and sulphur in the environment.
According to a UN study, extremely fine carbon particles that are emitted through motor exhaust can penetrate the deeper recesses of human lungs, causing serious respiratory problems. Major fuel sector pollutants include carbon monoxide, sulphur dioxide, nitrogen dioxide and lead, with the last mentioned being particularly injurious for growing children.
Carbon monoxide is the most toxic common urban air pollutant, because it reduces the oxygen-carrying capacity of the blood. According to available data, carbon monoxide levels in the range of 8-30 parts per million (ppm) and 6-40 ppm have been recorded for Lahore and Karachi respectively. It is said that an eight-hour exposure to these levels of carbon monoxide can cause temporary impairment of the nervous system functioning, including eyesight sharpness. Laboratory tests have demonstrated that nitrogen oxide levels of 100 ppm can cause illness if breathed for a short time while a 30-minute exposure to 700 ppm can prove fatal.
Sulphur dioxide, a compound of sulphur whose content in Euro-I is dangerously high, can cause acid rain. It causes irritation to eyes, nose and throat as well as to lungs. It is also highly damaging to plants. However, the lead particles contained in motor exhaust fumes are the most dangerous vehicle-related emission.
In a study conducted in Rawalpindi and Islamabad in 2000, the lead levels in the atmosphere at five sites ranged from 0.71 to 10.93 g/m, while the lead level in Lahore's atmosphere at five sites varied from 0.89 to 7.89 g/m. These levels are very high as compared to the WHO guidelines for lead concentration in ambient air based on annual average of 0.5 to 1.0 only. The amount of lead released from vehicle emissions into the air in Pakistan is estimated at 520 metric tonnes, which provides a disturbing measure of the severity of threat to the national health. Incidentally, lead is added to gasoline to increase the octane rating, and to reduce engine knock.
When young and growing children are exposed to lead pollution, it gets deposited in their brain tissues, leading to a lower IQ, and even to mental retardation. The damage is irreversible in most cases. It is due mainly to this reason that all industrialised countries have moved towards lead-free gasoline.
Motor vehicle emissions in many urban centres of the country account for as much as 90 percent of the total annual emissions of hydrocarbons, aldehydes and carbon monoxide, and for smaller but still the largest proportion of emissions of sulphur dioxide and nitrogen oxides. The severity of the problem can be gauged from the fact that an average vehicle in Pakistan emits 20 times as much hydrocarbons, 25 times as much carbon monoxide, and 3.6 times as much nitrogen oxides in grams per kilometer as an average vehicle in the United States! Along with its campaign to induce the refineries to switch over to Euro-II diesel, the government should launch a campaign in both electronic and print media to encourage the use of CNG, which is known as a cleaner fuel. Long-term damage to the country's environment and ecology can be averted if the government pursues its environmental targets with greater determination.