Why Industries are considered to be one of the potential known sources of Air Pollution in India? – Answered!

Industries are considered to be one of the potential known sources that release toxic gases, fumes, vapors and particulate matter into the immediate work environment and the general living environment, which causes deterioration in the quality of air that we breathe and ultimately affects our health.

Let us examine today the environmental pollution problem posed to the living environment of Greater Bombay which is blessed with 60 percent of the total industries of Maharashtra State.

According to one emission inventory estimate, a refinery of capacity 3.7 million tonnes of crude oil per annum pollutes the environment by throwing 52.8 tonnes of sulphur dioxide, 4.6 tonnes of nitrogen oxides, 28.5 tonnes of hydrocarbons, 0.7 tonnes of particulate matter and 76.5 tonnes of carbon monoxide into the atmosphere every day.

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Likewise, a fertilizer plant manufacturing 140 tonnes of sulphuric acid can emit 20.9 kg of sulphur dioxide per tonne of acid produced.

A factory manufacturing lubricating oils was found to emit about 22 tonnes of sulphur dioxide, a by-product of fuel oil combustion and the burning of hydrogen sulphide in the flare. An olefin plant consuming 200 metric tonnes of naphtha per day for reducing 6 metric tonnes of toluene, one metric tonne of acetylene, 15 metric tonnes of propylene, 55 metric tonnes of ethylene, and 15 metric tonnes of benzene per day, was estimated to release 5.28 metric tonnes of sulphur dioxide, 4 metric tonnes of oxides of nitrogen and 2 metric tonnes of hydrocarbons per day into the atmosphere.

A group of 155 cotton and textile mills of Bombay are capable of emitting 74 tonnes of sulphur dioxide, 12.2 tonnes of nitrogen oxides, 3.7 tonnes of particulate matter, 10 tonnes of cotton fluff and 40 tonnes of kerosene vapour into the living environment every day.

It is estimated that a total of 10,000 tonnes of pollutant are thrown into the Bombay environment per day.

Undoubtedly such emission inventories may not reflect the exact degree of emis­sions, but they definitely indicate the pollution potential that exists if it is not arrested or minimized by adopting suitable control technology.

Although enough information on the total pollutants emitted by various industries in the country is not available, according to one estimate 2.548 million tonnes of carbon mono- oxide, 5.475 million tonnes of sulphur dioxide, 1.858 million tonnes of nitrogen oxide, and 0.26 million tonnes of hydrogen sulphide are thrown into the atmosphere in India annually.

There have been a few studies conducted by the National Environmental Engineering Research Institute, Nagpur, Society of Clean Environment, and other such organizations to identify and quantify the levels of harmful pollutants in some localities.

For instance, it is known that Chembur-Bombay region is highly polluted because of indiscriminate discharge of pollut­ants into the atmosphere provides some of the data available on some of the important industrial cities in India, indicating average as well as the maximum concentration for sulphur dioxide, nitrogen oxides, hydrogen sulphide and particulate matter.

Some of the results of sulphur dioxide measurement in the different localities of Greater Bombay are presented the high incidence of asthma, bronchitis, coughs, breathlessness, sneezing and nasal blockage in the area are found to be associated with the high levels of sulphur dioxide prevailing in the atmosphere surrounding the Chembur area.

It is interesting to note that concentrations of pollutants vary widely during the day. Diurnal and seasonal variations of atmospheric sulphur dioxide, total oxidants (including ozone) and nitrogen dioxide at the BARC side were studied in 1972, as four hourly average concentrations.

The pollution levels of some toxic chemicals in the work environment of a few typical industries as revealed by the studies conducted by the Central and the Regional Labour Institutes are presented.

A critical examination of the data would definitely convince one that the prevalence of toxic chemicals, at levels higher than their permissible standards, requires immediate attention to prevent adverse effects to health.

The pollution problem of the immediate work environment may be further aggravated by the growth of industries and by the introduction of new hazardous chemicals with inherent moderate to high toxicity to which a large number of workers would be exposed.

Some data on the extent of increase of typical industries and the workers along with the possible environment pollutants are presented the data show that, within a period of 4 years, the number of workers exposed to several pollutants in industries such as chemicals, plastics and petroleum, cotton and textiles and sugar, increased substantially.

For instance, in the cotton and textile industry, where pollution of work environment by cotton dust, in levels more than 0.2 mg/m’ can cause byssinosys, the work force increased from 9, 34,000 to 10, 42,000.

In the sugar industry, where the exposure to bagasse dust can result in Bagassis a lung disease, the workers strength increased from 1, 19,000 to 1, 30,000. The chemical industry wherein a large number of toxic chemicals with cyanogen, carcinogenic, mutagenic and other health impairing properties are used, also witnessed an increase in the strength of workers from 2, 69,000 to 11,000.

This indicates that the problem of air pollution in the work environment of industries has a greater possibility of causing adverse effects to the health of workers in comparison to the general living environment, where the pollutants get diluted several folds before reaching localities.

Industry wise, the manufacture of caustic soda, using mercury as a cathode, posse’s environmental pollution problem due to the escape of metallic mercury vapours and chlorine from different streams, joints, etc

Exposure to mercury vapours for prolonged periods has been found to cause the manifestation of the signs and symptoms of nervousness, tremors, loss of teeth, stomatitis, kidney damage, etc.

The vapours of this metal being colorless and odorless are hard to detect. 80 percent-of the vapour inhaled are absorbed and the pres­ence of mercury can be estimated in the body fluids.

The pollution effects of lead and its compounds also require attention. Lead compounds are present either in the form of dust or gases or vapour and if absorbed in the body, it may lead to anaemia, renal colic, gingivitis, bonearrow, etc.

Zinc and lead smelters, storage battery manufacture, printing presses, and refineries while soldering and blending of lead tetraethyl with gasoline are some examples of plants which emit these toxicarits.

It is true that rapid industrialization in the country poses problems of air pollution and consequently adversely affects health but this growth cannot be stunted or dwarfed as it helps provide minimum requirements of employment, basic needs of clothing, food and shelter in a developing country.

It is, therefore, a great challenge for industries to realize their social obligation towards the society by minimizing pollution at work and the general living environment.

For this, feasible and economically viable equipment and techniques for con­trolling pollution, irrespective of its location, must be provided. Pollution caused by sulphur dioxide in sulphuric acid plants can be reduced from 2,000-5,000 ppm to 500 ppm by using the Double Catalyst Double Absorption (DCDA) technique.

Likewise, fluorine evolved in the manufacture of phosphoric acid and phosphate fertilizers can be successfully absorbed by using a properly designed plant, thus, abating air pollution. Industries may have to spend 1 – 2 percent of their total outlay incorporating control devices for air pollution abatement.