Municipal Solid Waste in Delhi: Ambient VOCs, Health Risks, GIS Modeling, Management, Policy Intervention, Climate Change and a Manmade Disaster in Waiting

Abstract

The increasing population pressure in today’s world has lead to the increase in the different types of waste on the earth and one of them being the solid waste. Solid wastes are constituted of different type of inorganic and organic material which releases different types of pollutants. In present study, total volatile organic compounds (TVOC) and individual VOC (benzene, toluene, ethylbenzene, m/p-xylene and o-xylene) in ambient atmosphere of Okhla solid waste landfill site of National Capital Region of India have been measured. The study has been carried out during two seasons i.e., winter and summer. The measurement of TVOC was done by using Real-time monitoring was done for TVOC using a data-logging photo-ionization detector. In addition to this, NIOSH-1501 standard method was used for individual VOC measurement using Gas Chromatograph. The mean levels of TVOC exhibited the concentration of 526.7μg/m³ while ΣBTEX showed the concentration of 148.1μg/m³ Okhla landfill site during the studied period. It is clearly noticed that the levels of TVOC were found to be higher in the morning, lower in the mid-day and increased during evening hours. Seasonal and diurnal variability of TVOC and ΣBTEX might be due to the emission sources and prevailing meteorological conditions. Toluene and benzene had significant concentrations among the studied VOCs. The strong positive correlation has been found among BTEX during winter as compared summer which suggested similar sources of VOCs. On analysis of theoretical health risk assessment, it is found that the benzene has contributed the largest in non-cancer hazard as compared to others VOCS. It is also found that the observed Lifetime Cancer Risk (LCR) has exceeded the standard guideline value (1.0 E-06) established by WHO. Due to the release of greenhouse gases (nitrous oxide, methane and carbon dioxide), solid wastes have potential to contribute to global warming and climate change in short term and long term period. The proper management also requires the proper use of information system in the form of GIS. For the sustainable environment, there is need for change in attitude of peoples towards the consumerism, proper management through separation of solid waste at source and sink, recycling it to reusable product like compost, generation and capture of methane, invention of easily degradable plastic are the need of the day so as to avoid a manmade disaster.