Investigation of Volatile Mono-Aromatic Hydrocarbons and 1,3-Butadiene in an Urban Metropolis, India.

In urban areas, benzene, toluene, ethyl benzene and xylenes (BTEX) constitute up to 60% of nonmethane VOCs. The present work was conducted to determine the ambient volatile 1, 3-butadiene and mono-aromatic hydrocarbons in an urban metropolis of Nagpur, India. Continuous sampling was carried out at high density traffic junctions, major petrol filling stations along with some residential areas during March to May, 2011. The samples were collected in 10 litre tedlar bags during the peak hours and analyzed within 24 hours by VOC analyzer based on Gas Chromatography-Photo Ionization Detection technique. Appreciably high concentrations of Total BBTEX were observed at petrol filling stations (237.1 µg/m3) and traffic junctions (134.3 µg/m3). The levels of BBTEX observed around a major traffic junction were significant to commuter exposure. In view of the health impacts to commuter, nearby residents and occupational exposure, preventive measures like use of CNG, installation of vapor recovery system at petrol filling stations and use of mask by the workers were needed. The correlation analysis and concentration ratio study indicates the impacts of petrol pumps and vehicular traffic on the urban air quality at the residential sites. The levels of benzene were well within the National Ambient Air Quality Standards at all the residential locations.

Decolorisation, biodegradation and detoxification of benzidine based azo dye.

The present study deals with the decolorisation, biodegradation and detoxification of Direct Black-38, a benzidine based azo dye, by a mixed microbial culture isolated from an aerobic bioreactor treating textile wastewater. The studies revealed a biotransformation of Direct Black-38 into benzidine and 4-aminobiphenyl followed by complete decolorisation and biodegradation of these toxic intermediates. From cytotoxicity studies, it was concluded that detoxification of the dye took place after degradation of the toxic intermediates by the culture.

A study of electro-mechanical and infrastructure instrumentation facilities in environmental laboratory.

Environmental laboratories carry out measurement and analysis of a number of physical, chemical and biological parameters. Each parameter requires some sort of instrument for its determination. Providing efficient instrumentation services to various departments of the Institute is an stupendous task. Instrumentation services in the form of installation, operation, repair and maintenanace of electro-mechanical equipment requires an in-depth experience and knowledge of the working, fabrication, design and repair of similar type of instruments so that the need of space, installation pre-requisites, budget constraints, availability of essential spares parts could be assessed. The paper discusses the operation of an environmental instrument repairs and maintenance, and audio-visual facilities. Suggestions for drafting of the proper specifications for procurement of laboratory equipments, such as ovens, furnaces, refrigerators, blowers, audio visual aids, and spares and accessories are given in this paper. The paper also gives the detailed information on various aspects that are needed for checking and testing of the equipment against specification before putting it in operational use. Development of a preventive maintenance program involving QC checks and keeping an inventory of essential spares required are also discussed in this paper. It is felt that such services are essential in providing smooth support to carry out research and development activities of the Institute.

Assessment of occupational exposure to VOCs at the Gantry gasoline Terminal.

The gasoline components dispersed in the workplace environment have direct impact on human health because of their carcinogenic and mutagenic potential. The volatile portion of these compounds generally consists of a mixture of monoaromatics such as benzene, toluene, ethylbenzene, xylenes and substituted benzene compounds. Investigation of levels of these chemicals at the petroleum liquid storage, and distribution facilities is of growing importance for assessing the occupational exposure of workers at these locations. A continuous monitoring was conducted at the Gantry Terminal of a refinery with portable samplers for determining 8-hr TWA at various locations involving petroleum liquid loading and distribution in road tank trucks, rail cars, and drums. After thermal desorption, the concentrations were determined in the laboratory with advanced Varian Model 2200GC/MS system. TVOCs level ranged between 0.10 to 1.97 mg/m3.The 8-hr TWA for benzene, toluene, and xylenes were low and within the limits for occupational exposure of gasoline components.

Investigation of GC detectors performance and validation.

Detectors in gas chromatographs are used in many different ways. The functions varies with the requirement of sensing the chemicals at trace levels to measuring quantitatively the relative amounts of compounds in ppb to sub ppb levels. The requirement of minimum detectable sensitivity for GC detectors and its actual estimation during the analysis helps in assessing the performance of detectors and a stable response of the GC system. The paper reports the study carried out with a GC system equipped with detectors like Flame Ionization Detector(FID) and Electron Capture Detector(ECD). Both packed and capillary column have been used for estimating the minimum detectability of detectors. The FID sensitivity obtained is 1.14 coulombs/g C. The FID could minimum detect 2.65 x 10(-12) gram carbon per sec and ECD could minimum detect pesticides (Lindane) less than 1 femtogram. Such a procedure is useful for all those engaged in analysis with GC or are in the process of procuring good reliable GC system.

Operating environmental laboratories--an overview of analysis equipment procurement and management.

Management of equipment in an environmental laboratory requires planning involving assessment of the workload on a particular equipment, establishment of criteria and specification for the purchase of equipment, creation of infrastructure for installation and testing of the equipment, optimization of analysis conditions, development of preventive maintenance procedures and establishment of in-house repair facilities. The paper reports the results of such an analysis carried for operating environmental laboratories associated with R& D work, serving as an Govt. laboratory or attached to an Industry for analysing industrial emissions.

A comprehensive investigation of noise exposure in and around an integrated iron and steel works.

A comprehensive environmental noise exposure study was carried out in and around a major iron and steel works. The works was located in the central part of the city and was surrounded by residential, commercial, and sensitive receptors. Traffic activity near the plant was significant and added to the background noise level. Considering the variety of noise sources in the plant area and in the neighborhood, a practical approach to measure noise equivalent level in the plant and in the residential, commercial, industrial, and silence zone was adopted. A modular precision integrating sound level meter with statistical analyzer module, octave filter set, and calibrator were used during the measurements. The day and night level, Ldn, was determined. Worker exposure was assessed by determining the speech interference level (SIL), loudness level, and noise rating level at one of the major sources located in the power plant of the steel works. The results indicate that SIL was 94 dBA, loudness level was 112 phons, and the noise rating was in the range of 85-95. A traffic noise index also was determined near the works gates and was in the range of 68-96. The impact on the community is significant as observed from Ldn levels. Some mitigation measures for noise control are also discussed.

Development of low cost all glass recirculation systems for environmental applications.

Some simple glassware has been developed for recirculation of liquid medium. These glassware have wider applications and have been tested in experiments involving leaching, biodegradation, and desulfurization. The fabrication cost is minimum and can be developed in a small glassware workshop. Such a development has certain advantages as no separate mechanical devices are needed, the flow can be easily monitored due to transparency of the apparatus, acidic or alkaline medium can also be circulated. The paper discusses the development, design and fabrication of some specialized glass recirculation systems and its environmental applications.

Urban noise--a need for acoustic planning.

The noise status of growing urban centres of the country are very much required to develop acoustic design and planning guidelines for various land use classification. An attempt in this direction has been made by measuring noise equivalent levels for cities like Delhi, Jamshedpur, Dehradun and Nagpur. The choice of Ldn (Day-Night noise level) which is a better descriptor of noise quality provides an interesting status of noise in these urban centres. It has been observed that maximum percentage of areas in Delhi and Jamshedpur fall under moderately severe to very severe noisy conditions as compared to Dehradun and Nagpur on the noise rating scale. Ways and means are also considered for mitigation of noise.

Real time sound intensity measurements in an industrial complex.

The development of techniques and new tools for environmental acoustic measurements has opened up new ways and means to determine the source location, source ranking and energy flow path. The new tools posses versatile probes for different applications, better digital signal processing facilities and data presentation for sound pressure measurements--the quantity we hear, sound power measurements--the quantity emitted from a source, and the sound intensity measurements--the quantity of propogated sound power. The paper reports the results of real time sound intensity measurement carried out in an industrial complex with a portable sound intensity analyzer equipped with 1/3 octave filters and a dual microphone remote control probe for real time analysis. Extensive sound intensity measurement in the Power Plant, Ammonia Compressor House and Urea Compressor House have been carried out. The results are useful for sound power determination of various sources.

An investigation into the acid content of aerosols in the ambient air at the Taj Mahal, Agra.

A chemical analysis of suspended particulate matter (SPM) collected near the world famous Taj Mahal monument at Agra has been carried out. SPM samples collected on glass fibre filters were analysed for water-soluble sulphate, nitrate, chloride and ammonium ions. The data were derived from over 200 samples (each of 24 h), collected continuously during the winter periods (October through to March) of 1984-1985 and 1985-1986. The SO(4)(2-) and NO(3)(-) components are acidic in nature causing corrosion and effects on visibility, and so were studied in more detail. Mean values for SO(4)(2-) and NO(3)(-) derived from two-year data are 7.2 microg m(-3) and 8.2 microg m(-3), respectively. The SO(4)(2-)/SO(2) and NO(3)(-)/NO(2) ratiosobserved indicate faster conversion of SO(2) to SO(4)(2-) than NO(2) to NO(3)(-), the maximum levels being in January. Thus, both SO(4)(2-) and NO(3)(-) results appear to offer more promising indices of air quality than do SPM data alone.