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Asbestos: Foe or Friend?

Furquan Ahmad Ansari, Iqbal Ahmad Mohd. Yunus and Qamar Rahman

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Asbestos is grouped into two serpentine and amphibole. Serpentine group, which includes only chrysotile fibre, while amphibole covers actinolite, amosite, anthophyllite, crocidolite and tremolite.

Asbestos is characterized as long, thin, flexible, separable with high tensile strength, heat resistant and of course crystalline in nature. It is well known that the asbestos exposure threatens the normal life of occupational workers, neighbors, pets etc.

Across the globe, asbestos is being used for the manufacturing of more than 3000 different kinds of asbestos-based products including asbestos-cement pipes, asbestos-cement sheets, brake-shoes, brake linings, electric heater plates etc. (Ramanathan and Subramaniam, 2001).

In India alone more than 30 mines are operational in Andhra Pradesh and Rajasthan. About 2500 tonnes of chrysotile (Serpentine) and 36,500 tonnes of tremolite (Amphibole) asbestos are annually mined in India. Asbestos production at present is about 2000 tonnes per month from their own mines in Andhra Pradesh, Rajasthan and Bihar. In addition, India imports asbestos worth Rs 40 – 50 crores annually, without mentioning any remarks of hazardous product (Govt. of India., 1997,1999). The tremolite asbestos variety of amphibole group mined accounts 58% in Rajasthan. Tremolite and Anthophyllite are the largest amphibole deposits in Rajasthan known so far (Mansinghka and Ranawat, 1996).

In India asbestos mining and milling is concentrated to the mainly small-scale sector. Asbestos deposits in Rajasthan are primarily located in Beawar, Deogarh and Jharol ultramafic belts (Mansighka and Ranawat; 1996).

Occupational exposure though inhalation is the most hazardous to industrial workers. During the asbestos-based industrial activities whether related to mining, milling or manufacturing, asbestos fibers get airborne at the work places. The people living in the vicinity of asbestos mines and asbestos related industries might be exposed to higher levels of asbestos (Case and Sebastein, 1987).

Epidemiological surveys and experimental studies have confirmed that asbestos acts as carcinogen as well as co-carcinogen. Its prolonged exposure causes progressive pulmonary fibrosis (asbestosis), pleural diseases (pleural plaques and effusion), malignancies as mesothelioma and bronchogenic carcinoma (Rahman et al, 1993, Rahman and Athar, 1994, Mossman et al, 1996). This article is focused on the unorganized units of grinding and milling processes of Beawer, Deogarh in Rajasthan. Most of the units are not registered by any Government agencies. These units presently exist in these areas mainly producing asbestos cement pipes and pillars as mentioned above. These unorganized small-scale units consuming asbestos depend on the indigenous asbestos supply from local sources. Mostly these units exist in the corner or far distance from central village or public place; such units are running by only very small number of workers. Further it seems that these workers are not aware about the hazardous nature of asbestos and the children, infants of workers were found to be playing along with pets like goats, dogs etc were also present in the vicinity premises. Goats grazing in asbestos contaminated fields inhale an asbestos fibre, which causes parietal and pleural plaques (Dumortier P., 2002). People living in the vicinity of these units are also at higher risk. (Selikoff et al; 1980).

Fibre Toxicology Division Industrial Toxicology Research Centre,
Post Box - 80, M. G. Marg Lucknow-226 001
E-mail: [email protected] Dean, Department of Environmental Sciences Babasaheb Bhimrao Ambedkar University (A Central University)

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