Air pollution: High levels of Benzene, CO, RSPM continue to haunt city
| Date :18-Nov-2019 |
Staff Reporter :
Nagpur has the highest Benzene concentration in State, reveals MPCB’s latest report
If you think that Delhi is far away from Nagpur, you are right. But, as far as air pollution is concerned, Nagpur appears to be slowly moving towards Delhi’s direction. The ‘Air Quality Status of Maharashtra 2018-19’ report prepared by Maharashtra Pollution Control Board (MPCB) and The Energy and Resources Institute (TERI) reveals that levels of Benzene, Carbon Monoxide (CO), and Respirable Suspended Particulate Matter (RSPM) are high in Nagpur. There are 72 active Ambient Air Quality Monitoring Stations (AAQMS) representing 25 cities in the State. In 2018-19, total 10,164 observations were recorded from these AAQMS.
As per the MPCB and TERI report, more than 68 per cent (6,996) of the observations were found to be in ‘Good’ and ‘Satisfactory’ categories, up from 65 per cent in the same category in 2017-18, ‘thus recording an improvement’. The share of observations in ‘Moderate’ category recorded a ‘slight decrease’ from 30.6 per cent in 2017-18 to 29.38 per cent in 2018-19. “A similar trend was observed in the case of polluted categories, with percentage share of ‘Poor’ category observations getting reduced from around 3% to ~1.4% and that of ‘Very Poor’ category getting reduced from a little less than 2% to merely 0.2% in this year,” it adds. However, a deeper scrutiny reveals that in case of Nagpur, situation is not so rosy. Though Nitrogen Oxides (NOx) concentration was less than 40 µg/m3 in 2018-19, it was higher than that recorded in 2017-18. In fact, the report reveals, Nagpur region recorded a rise in NOx concentration from 32 µg/m3 in 2017-18 to 38 µg/m3 in 2018-19, ‘thus edging towards the permissible limits’. Nagpur showed an increasing trend in NOx concentrations, with the levels reaching closer to the standard limits. As far as CO levels are concerned, the report reveals that those were found to be ‘exceeding the 8 hourly concentration standard (2.0 mg/m3)’ in Nagpur.
“CO concentrations exceeded the standard limit mainly in the post-monsoon months (October to February). This trend was observed in almost all CAAQMS installed in Maharashtra region,” states the report. The CO concentration was well within the standard limit in Nagpur for the whole year 2018-19 except in the month of October, November and December 2018, when it ‘increased slightly’ and reached 2.07 mg/m3, 2.21 mg/m3, and 2.02 mg/m3 respectively. In January 2019, it recorded a concentration of 1.91 mg/m3, which was closer to the standard limit.
Against this backdrop, the MPCB-TERI report suggests that Nagpur needs to ‘implement strategies to reduce the high levels of carbon monoxide concentration, especially in the winter or post-monsoon months’. The levels of RSPM in all regions of Maharashtra have always exceeded the standard limit of 60 µg/m3. Even regions with lower limits of SO2 and NOx showed trends of high levels of particulate matter concentrations. As per the chart in the report, RSPM concentration in 2018-19 was almost the same as that in 2009-10. Though RSPM concentration had dropped from 2014-15 to 2017-18, it rose sharply in 2018-19. A more serious aspect relating to Nagpur’s air quality is that it tops the State chart in Benzene levels. The standard limit for Benzene as per Central Pollution Control Board is 5 µg/m3.
In 2018-19, Benzene levels were found to be 1.3 times higher as compared to the standard permissible limit (5 µg/m3) consecutively for seven months (October 2018 to April 2019) in Nagpur. Benzene levels were found to be above the permissible limit predominantly in winter and summer. In case of Ozone, CAAQMS in Nagpur recorded ‘high levels’. Compared to the standard limit of 100 µg/m3, CAAQMS at Nagpur recorded Ozone levels in the range of 100-123 µg/m3 ‘exceeding the standard limit’ especially in winter and summer. The levels were within the standard limit in 2017-18, but rose in 2018-19. The monitoring station in Nagpur recorded ‘excessive’ Ozone concentrations in February 2019 (138.5 µg/m3) and March (119.3 µg/m3). The annual average of SO2 concentrations recorded were well within the standard limit in all regions of Maharashtra. However, Nagpur showed a slight increase in SO2 concentration. Thankfully, it was still well below the permissible limit.
However, the MPCB-TERI report has a word of caution too: “Though the levels are below the permissible limit, these regions have continued to show urban infrastructural growth, including in the industrial and commercial sectors. Hence, continuous monitoring and effective mitigative measures need to be taken in advance for avoiding any future problems related to pollution.” In Nagpur region, the report states, the percentage share of observations under ‘Moderate’ category was found to be high in AAQMS installed at North Ambazari Road (58 per cent), MIDC Office, Hingna Road (approximatly 72 per cent) and Government Polytechnic College, Sadar (approximately 55 per cent). The remaining observations were under ‘Satisfactory’ category of Air Quality Index. Civil Lines and Nagpur CAAQMS, on the other hand, recorded a high percentage of observations under ‘Good’ and ‘Satisfactory’ categories, with a percentage share of around 94 per cent and approximately 61 per cent respectively.
Better monitoring, stringent measures needed: Chopane Given the situation, better monitoring of air quality and stringent measures to counter pollution are needed to tide over the unfolding crisis, said Prof Suresh Chopane, President, Green Planet Society. Prof Chopne told ‘The Hitavada’ that monitoring stations should be in dense localities as well as in industrial areas to get the correct picture. For want of these, the picture does not show the ground reality. Besides, measures like curbs on number of vehicles per household, more efficient monitoring in residential areas are required to be taken. “Usually, there is focus on industrial emissions only. In the past some years, the situation on the front of industrial emissions is improving.
Now, the indoor and outdoor pollution especially in urban areas is increasing,” Prof Chopne said. According to him, most of the big cities in Vidarbha are affected due to air pollution. Chandrapur, followed by Nagpur and Amravati have the worst Air Quality Index in Vidarbha. RSPM concentrations increase due to emission from vehicles, burning of waste and coal, building construction etc. NOx emission from vehicles contributes to increase in Ozone concentration. However, he alleged, concerted efforts were not being made considering the seriousness of the situation. In case of Chandrapur, he said, two action plans came but not much improved on ground.