Author: Chalani Rubesinghe.
The toxicity of asbestos is well-known, and as such its use has been banned in more than 40 countries. Yet Sri Lanka is behind in this process.
Asbestos is still used in many construction materials and automobiles. People exposed include workers who are engaged in asbestos related industries or in its transportation or its handling at sales outlets and the many citizens who spend the entirety or just part of their lives under asbestos roofs. Health threats from exposure to asbestos include mesothelioma, asbestosis, lung cancer, gastrointestinal tract cancers, diffuse pleural thickening and warts or corns in the skin. Health effects generally appear after 15 years or more from the first exposure and interestingly, keep progressing even when exposure is stopped.
Although Sri Lanka has the legal backing to ban the use of asbestos, more policy actions are necessary for its proper management and for banning or phasing out its use. It should not be difficult to find asbestos alternatives and treating mechanisms. Indeed, examples of these are already available from many parts of the globe.
- Applications of asbestos
- Contamination Situation in Sri Lanka
- Exposure studies from other countries
- Health effects
- Reducing the threat of Asbestos
- Getting tested
- Status of asbestos use, in Sri Lanka
- Legal status of Asbestos in Sri Lanka
- Issues to be addressed immediately
- Policy recommendations
In Sri Lanka, asbestos has only recently been recognized as a toxic substance to which the general public are exposed. Yet its hazardousness has remains the same for humans throughout the world.
The dangers of Asbestos came to the fore following the discovery of its link to mesothelioma, a type of cancer, in persons exposed to asbestos over an extensive period of time. Since then more than 40 countries, including all member states of the European Union, have banned or phased out the use of all forms of asbestos. Yet in Sri Lanka this is a hidden toxin which rarely gets the attention it requires.
Asbestos is a mineral that occurs naturally and has several forms, namely; chrysotite, Amosite, Crocidolite, tremolite asbestos, actinolite asbestos, and anthophyllite asbestos. It is the strength, heat and chemical resistivity of asbestos fibers make it appear to be an ideal material for use in number of products.
Applications of asbestos
Asbestos is generally found in: asbestos gaskets, cigarette filters, fire proofing & prevention materials, plastics, vinyl products, asbestos sheets, electrical cloth & electrical panel partition, fume hoods & laboratory hoods, textile cloths & garments, construction products, adhesives and Gold Bond adhesives, ductwork connectors & flexible duct connectors, insulation, construction mastic & gunning mix, floor backing, drywall taping compounds and zonolite insulation
Contamination- Situation in Sri Lanka
Contamination of Asbestos mainly occurs through inhalation and ingestion.
In Sri Lanka, asbestos is mainly used in roofing and ceilings. An asbestos sheet is not a harmful material as long as it remains on a roof in a good condition. However, it is common practice among carpenters in Sri Lanka to cut the asbestos sheets to the required size. During this process, massive amounts of asbestos dust are generated. It is this dust which can then cause serious health problems.
Once released, the dust is inhaled in large quantities by workers without protective gear. In addition, through their clothes and on other equipment, they become carriers of this toxic dust. Where they transport it to their homes, their children and other family members are then also exposed.
The release of asbestos ‘fibres’ does not just occur during cutting; dust is also released when mosses are scraped from roofing sheets and during the natural decay of asbestos, in sheets or in asbestos containing materials, which are often carelessly dumped.
Careless dumping and transport are major contamination pathways. Even among the factory workers, the majority do not wear any protective gear during their work. It is quite surprising that they do not get traced of being one amongst majority recorded with the cancer diseases.
From childhood to adulthood, most of Sri Lankans spend the time beneath asbestos roofs; most of the schools use asbestos roofing sheets or have asbestos ceilings. These could be damaged and decaying which expose fibers to the environment. Yet there is no measure to see the exposure levels.
Since children enjoy playing in the dirt, they are more vulnerable to asbestos exposure, if the dirt they are playing contains asbestos, they inhale the dust and may also ingest while taking food with their dirty hands. In the Sri Lankan situation, especially as asbestos sheets are freely dumped in the backyard and children like to observe their world around.
House trained cats and dogs can also bring asbestos into the home by carrying dust or dirt on their fur or feet if they spend time in places that have high levels of asbestos in the soil.
There are no proper records on cancer patients in Sri Lanka, which is a major missing in proving the threat of these contaminants in the environment. Information on health effects of Asbestos given by Agency for Toxic Substances and Disease Registry (ASTDR) concludes that there’s a strong relationship between respiratory cancers (cancers of the lung and mesothelioma) and exposure to asbestos in human. Whereas the Statistics available in Sri Lanka (in 2007) points out that, out of 10725 new patients registered during the year 2007, 7200 patients were identified as malignant. Among whom the top three malignancies in males (3204 patients) were carcinoma of bronchus, lung, oesophagus and prostate. It’s only having not tested whether this is exactly due to asbestos, which has no meaning when it gets to the malignant stage.
Since asbestos are mainly used in building components, carpenters, building maintenance, repair and demolition workers are mostly exposed to high levels of asbestos fibers. In Sri Lanka people engaged in solid waste removal and management and workers engaged in Asbestos transportation and handling at sales outlets are also exposed to asbestos dust.
According to the European Directive of the EC 2003/18, permissible limits are 0.1 [f/mL] for all types of asbestos, based on an 8-hour time-weighted average (8h-TWA). The same limit is in force in most Canadian provinces (Alberta, British Columbia, Manitoba, Ontario, Newfoundland and Labrador, Prince Edward Island, New Brunswick and Nova Scotia); New Zealand; Norway; and, the USA. Other countries have permissible limits of up to 2 fibres/cm3.
For some luck, Sri Lanka does not have asbestos mines. All the manufactures use asbestos imported from other countries. That reduces the sources of exposure to asbestos products and their dumping sites.
Exposure studies from other countries
A study conducted by Agency for Toxic Substances and Disease Registry (ATSDR, 2000), shows that the measured asbestos concentration in indoor air of homes, schools and other buildings ranged between 30- 6000 fibers/ m3. This variation depended on whether the asbestos-containing material is in good condition or deteriorating and the type of application such as insulation, ceiling and floor tiles.
Despite the total ban of asbestos, about 1500 workers (mainly construction workers and auto mechanics) were reported as having exposure to asbestos on the Finnish Register of Workers exposed to Carcinogens (ASA Register) in 2006.
In 2004, approximately 61000 workers performing demolition and reconstruction work in Germany were registered in the Central Registration Agency for Employees Exposed to Asbestos Dust.
According to a study on Swedish asbestos cement workers, the highest exposure levels of asbestos concentrations were identified in the milling and grinding operations.
A Finnish study shows that during break repair of trucks or buses, the estimated 8-hour time-weighted average exposure to asbestos was 0.1–0.2 [f/mL], while high levels of exposure (range, 0.3–125 [f/mL]; mean, 56 [f/mL]) were observed during brake maintenance if local exhaust ventilation was not used. Other operations such as cleaning of brakes with a brush, wet cloth or compressed air jet without local exhaust, the concentration exceeded 1 [f/mL] .
In United Kingdom, the high risk jobs on Asbestos contamination has included school teachers. According to the health statistics published by the HSE (Health and Safety Executive, UK), deaths from mesothelioma, continue to increase in the UK (from 153 in 1968 to 2,347 in 2010).
The study carried out by Michael Lee, one of the founder members of the Asbestos in Schools Group (AiS), showed that the numbers of school teachers dying of mesothelioma is on the increase. In figures, 17 school teachers and 3 teaching and educational support assistants died of mesothelioma in 2011. This compares with an average of 13 school teachers a year between 2001 and 2005, and 15 between 2006 and 2010. Researchers in the US points out that for every death of a teacher from asbestos related diseases, 9 children will die. In June 2013 the Government’s advisory committee on cancer concluded that children are more at risk from exposure to asbestos than adults, being more vulnerable because they have longer than adults to develop work related diseases related to the material.
According to the World Health Organization, about 125 million people in the world exposed to asbestos at the workplace. Global estimates show that at least 90 000 people die each year from Asbestos related lung cancer, mesothelioma and asbestosis resulting from occupational exposure.
Asbestos fibers enter the body when a person breathes in. The body can get rid of the large fibers but microscopic fibers can pass in to the lungs causing diseases. The body can naturally get rid of any asbestos fibers entering through the mouth and asbestos fibers cannot be absorbed through the skin.
The monograph published by the International Agency for Research on Cancer (IARC), gives important information on relationship of asbestos on cancer. Breathing Asbestos fibers can lead people to develop;
- Asbestosis – an irreversible scarring of the lungs that causes a decrease in elasticity. An industrial disease that was associated with past high levels of exposure of all types of asbestos.
- Lung cancer – increased incidence in those working with chrysotile, amosite, anthophyllite, and with mixed fibers containing crocidolite, and tremolite.
- Mesothelioma – cancer of the lining of the chest or abdominal wall. Pleural and peritoneal mesotheliomas were reported to be associated with occupational exposures to crocidolite, amosite, and chrysotile. mesothelioma may also occur among individuals living in neighborhoods of asbestos factories and crocidolite mines, and in persons living with asbestos workers.
- Diffuse pleural thickening – a non-malignant disease affecting the lung lining
- Gastrointestinal tract cancers these were reported to have been demonstrated in groups occupational exposed to amosite, chrysotile or mixed fibres containing chrysotile.
Long and thin fibers retain in the lung longer. They are comparatively more toxic than short and wide fibers as these fibers reach the lung and pleura. Fibers of amphibole asbestos such as tremolite asbestos, actinolite asbestos, and crocidolite asbestos are retained longer in the lower respiratory tract than chrysotile fibers of similar dimension.
Information on the health effects of asbestos in people comes mostly from studies of people who were exposed in the past, to levels of asbestos fibers (greater than or equal to 5 μm in length) in workplace air that were as high as 5 million fibers/m3 (5 fibers/mL). The effects of asbestos in workers generally show after 15 years or more after the first exposure to asbestos.
The effect or the disease can increase with factors such as;
- The type of the asbestos fibers that they are exposed to
- The amount of fibers they inhale
- The number of times they are exposed
- The duration of time they exposed to
- Exposure to asbestos can increase the likelihood of lung cancer, mesothelioma, and non-malignant lung conditions such as asbestosis (restricted use of the lungs due to retained asbestos fibers) and changes in the pleura (lining of the chest cavity, outside the lung).
- Changes in pleura such as thickening, plaques, calcification, and fluid around the lungs (pleural effusion) may be early signs of asbestos exposure. These changes can affect breathing more than previously thought. Pleural effusion can be an early warning sign for mesothelioma (cancer of the lining of the lungs).
- When asbestos fibers are inhaled, most fibers are expelled, but some can get stuck in the lungs and remain there throughout life. Fibers can accumulate and cause scarring and inflammation. Enough scarring and inflammation can affect breathing, leading to disease.
- Most cases of mesothelioma are diagnosed 30 years or more after the first exposure to asbestos.
- Asbestos-related disease has been diagnosed in asbestos workers, family members, and residents who live close to asbestos mines or processing plants.
- Health effects from asbestos exposure may continue to progress even after exposure is stopped.
- People exposed to high concentrations of asbestos, for longer periods of time, and/or are exposed more often have a higher risk of getting an asbestos related disorder/s.
- Inhaling longer, more durable asbestos fibers (such as tremolite and other amphiboles) contributes to the severity of asbestos-related disorders.
Health effects of asbestos in contact with skin reveal the formation of small “warts” or corns. The example comes from a group of workers installing amosite insulation in ships; nearly 60% of the people had one or more of these lesions, mostly on the hands (Alden and Howell 1944).
Reducing the threat of Asbestos
- Be aware of the source of exposure
- Regular hand and face washing to remove asbestos-containing dusts and soil, especially before meals, can lower the possibility of asbestos fibers on the skin being accidentally swallowed while eating.
- Door mats can help lower the amount of soil that is tracked into the home; removing your shoes before entering will also help.
- Planting grass and shrubs over bare soil areas in the yard can lower the contact that children and pets may have with soil and reduce the tracking of soil into the home.
- If you are working related to any of the activities that are likely to contaminate your cloths with asbestos fibers, such as carpentry, demolition or maintenance of asbestos containing buildings, automobile repair and servicing, etc. showering or changing cloths before leaving work helps preventing toxic dust contamination in
As long as consumers are considered, any person who has any other material than asbestos, on their roof is strictly advised not to change. Those who have asbestos on their roofing, are advised not to scratch or cut dry asbestos sheets and have a coating paint on top of the Asbestos sheet and a ceiling of any other material to prevent exposure.
The x-ray can detect early signs of lung disease caused by asbestos. While other substances besides asbestos can sometimes produce similar changes in the lungs, this test is usually reliable for detecting asbestos-related effects produced by long-term exposures at relatively high concentrations of asbestos fibers.
- Gallium-67 lung scanning – to detect changes in the lung
- High-resolution computed tomography- detects changes in the lungs.
- Detection of microscopic asbestos fibers in pieces of lung tissue removed by surgery.
- Asbestos fibers detected in material rinsed out of the lung, mucus (sputum), urine, or feces. – but these tests are not reliable to estimate how much asbestos a person have been exposed to or to predict whether a person is likely to suffer any health effects.
Status of asbestos use, in Sri Lanka
Sri Lanka does not mine asbestos. 100% of asbestos are imported from different countries. They are used in roofing sheets, chemical insulation, Asbestos containing materials in machinery and in automobile components such as; break shoes, brake pads and clutch pads.
The safety measures and practices among workers engaged in manufacturing, transportation, building constructions, demolition and discarding are almost none. Asbestos are commonly found discarded in backyards and also used in simple garden decorations open for degradation.
Legal status of Asbestos in Sri Lanka
Sri Lanka ratified the Rotterdam convention since 19th January 2006, The Ministry of Agriculture being the national focal point and the Central Environmental Authority being the competent Authority in managing industrial chemicals. Main objective of this convention is to protect human health and the environment by sharing information on certain hazardous chemicals among parties and prior informed consent in international trade of chemicals (PIC).
Blue asbestos was banned in Sri Lanka since 1987, under the gazette Extraordinary No. 452/4, published on 6th May 1987 and only Chrysotile is used.
According to the Central Environmental Authority, a situation report and a policy recommendation report has been prepared while the preparation of a National Policy on usage of Asbestos related products is in process. In addition, several discussions have been carried out with all the stakeholders regarding the elimination of Asbestos related diseases in Sri Lanka.
After a meeting of Technical advisory committee for the management of Industrial Chemicals (TACMIC) in 2012, decisions were made to find out the possibilities of granting tax concessions for health and environment friendly non Asbestos products, awareness raising among public on health impacts of Asbestos products and also on the available alternatives including ceiling sheets and to restrict the approval for new Asbestos related industries and expansion for such existing industries.
Following, the Ministry of Environment and the Ministry of Health has submitted a joint cabinet paper to the cabinet and was granted the approval on 5th July 2012. The cabinet decisions included;
- To update the national database on Chemicals
- To identify priorities in management of carcinogenic chemicals in factories with the help of World Health Organization
- To minimize the effects of the carcinogenic chemicals in factories and
- To carry out a national program on carcinogenic chemicals.
Importation of asbestos:
Interestingly, the records of importation extracted from “External trade statistics” by Sri Lanka Customs shows the imported amounts of asbestos including blue asbestos. (Table 1) thus it is seen that regulations on paper does not ensure the safety in practical situation.
Table 1: Importation details from 2005 to 2008 for asbestos coming under the HS Code 2524….
|In year 2005
|25240009 – Other
|In year 2006
|25240009 – Other
|In year 2007
|25240001 – Blue Asbestos
|25240009 – Other
|252410 – Crocidolite
|252490 – Other
|In year 2008
Issues to be addressed immediately
Since the effects of asbestos contamination remains similar throughout the world, immediate steps should be taken to protect workers from extensive exposure while introducing a proper mechanism for disposal of Asbestos discarded from households, maintenance, production and demolition activities.
Since these items falls under hazardous waste, people should be made aware and effective mechanism should be introduced before these toxics are found in lungs.
- Policy should be brought up to manage the existing asbestos in use and also to introduce and popularize asbestos alternatives, if possible through the existing asbestos producing companies.
- Form regulations to prevent or reduce the exposure to asbestos,
- Form arrangements to deal with accidents, incidents and emergencies,
- Form regulations to prevent or reduce the spread of asbestos and safe removal.
A procedure has been suggested by the EU-Asia Project on sustainable Constructional waste management in Sri Lanka. This indicated procedure for Asbestos removal according to a technology developed by the Technology Regency International Group (UK) on Asbestos conversion. The main process steps of this includes; Loading, Shredding, Chemical bath (de-watering), Furnace (the rest of the moisture removing), Rotary kiln (1200 degrees, one hour), Ejecting and finally sealing.
Methods and mechanism are available in other countries on safe removal of Asbestos according to the contamination levels in the air.
For man has discovered worse chemicals first and the safer ones second, alternatives are now available for asbestos. (Table 2)
Table 2: Alternatives for asbestos products
|Fiber-cement roofing using: synthetic fibers (polyvinyl alcohol, polypropylene) and vegetable/cellulose fibers (softwood Kraft pulp, bamboo, sisal, coir, rattan shavings and tobacco stalks, etc.); with optional silica fume, fly ash, or rice husk ash
Micro-concrete (Parry) tiles
Galvanized metal sheets
Vegetable fibers in asphalt
Coated metal tiles (Harveytile)
Aluminum roof tiles (Dekra Tile)
Extruded uPVC roofing sheets
Recycled polypropylene and high-density polyethylene and crushed stone (Worldroof)
Plastic coated aluminum
Plastic coated galvanized steel.
|Asbestos-Cement Flat Sheet (ceilings, facades, partitions)
||Fiber-cement using vegetable/cellulose fibers (see above), wastepaper, optionally synthetic fibers
Gypsum ceiling boards (BHP Gypsum)
Polystyrene ceilings, cornices, and partitions
Façade applications in polystyrene structural walls (coated with plaster)
Aluminum cladding (Alucabond)
Galvanized frame with plaster-board or calcium silicate board facing
Softwood frame with plasterboard or calcium silicate board facing.
Cast iron and ductile iron pipe
High-density polyethylene pipe
Polyvinyl chloride pipe
Steel-reinforced concrete pipe (large sizes)
Glass-reinforced polyester pipeLow Pressure:
Cellulose/PVA fiber-cement pipe
Glass-reinforced polyester pipe
Steel-reinforced concrete pipe (large diameter drainage)
|Asbestos-Cement Water Storage Tanks
|Asbestos-Cement Rainwater Gutters; Open Drains (Mining Industry)
There is no debate on the toxicity of Asbestos. May it not been proved for Sri Lankans. It is just few decisions of policy makers that will be required to bring the change, including, replacement of the Asbestos fibers with an alternative. As for the general public the best option is to be aware and take measures at every step to prevent contamination of the toxic material/s.
- http://www.asbestos.com/products/ (Accessed 26 February 2014)
- http://www.atsdr.cdc.gov/asbestos/asbestos/health_effects/, Asbestos, Health Effects, ASTDR. (Accessed 31 January, 2014)
- http://www.ncisl.lk/statistic.php , statistics of National Cancer Institute. (Accessed 31 January, 2014)
- EU (2003). Directive 2003/18/EC of the European Parliament and of the Council of 27 March 2003 amending Council Directive 83/477/EEC on the protection of workers from the risks related to exposure to asbestos at work. Official Journal L 097, 15/04/2003 P.0048 – 0052.
- ACGIH (2007). Documentation of the TLVs and BEIs with Other Worldwide Occupational Exposure Values – 2007, Cincinnati, OH [CD-ROM].
- Saalo A, Länsimäki E, Heikkilä M, Kauppinen T (2006). ASA 2006. Syöpäsairauden vaaraa aiheuttaville aineille ja menetelmille ammatissaan altistuneiksi ilmoitetut Suomessa. (In Finnish)
- Hagemeyer O, Otten H, Kraus T (2006). Asbestos consumption, asbestos exposure and asbestos-related occupational diseases in Germany. Int Arch Occup Environ Health, 79: 613–620. doi:10.1007/s00420-006-0091-x PMID:16523318
- Albin M, Jakobsson K, Attewell R et al. (1990). Mortality and cancer morbidity in cohorts of asbestos cement workers and referents. Br J Ind Med, 47: 602–610. PMID:2207031
- Kauppinen T & Korhonen K (1987). Exposure to asbestos during brake maintenance of automotive vehicles by different methods. Am Ind Hyg Assoc J, 48: 499–504.PMID:3591672
- Elimination of Asbestos related diseases, (2006), World Health Organization.
- http://www.atsdr.cdc.gov/asbestos/asbestos/health_effects/ (Accessed 5 March 2014)
- Alden HS, Howell WM. 1944. The asbestos corn. Archives of Dermatology and Syphilology 49:312-314.
- www.atsdr.cdc.gov/toxprofiles/tp61-p.pdf (Accessed 5 March 2014)
- https://www.safework.sa.gov.au/…/How_to_Safely_Remove_Asbestos.pdf , (December 2011) by Safe Work Australia
- cowam.tec-hh.net/COWAM-presentation-PVC,asbestos.pdf, PVC and Asbestos waste management in Sri Lanka, EU-Asia Project on sustainable Constructional waste management.
- Substitutes for Asbestos-Cement Construction Products, by Barry Castleman Updated October 8, 2009 (Accessed on 20/ 02/ 2014)
- http://info.mayiclaim.co.uk/personal_injury_compensation_claim_news/bid/331511/Children-are-More-at-Risk-from-Asbestos-than-Teachers-in-Schools, “Children are More at Risk from Asbestos than Teachers in Schools” by Tony Wheeler on Thu, Jan 09, 2014.
-  Substitutes for Asbestos-Cement Construction Products, by Barry Castleman Updated October 8, 2009 (Accessed on 20/ 02/ 2014)