Asbestos in Soil Introduction to asbestos Presented by Jane Tierney July 2015 INSTITUTE OF OCCUPATIONAL MEDICINE www.iom-world.org
Presentation brief What is asbestos, naturally occurring • Where does it come from, importation into UK • Health effects and ongoing legacy • • Why was it used – unique properties • • Asbestos in buildings/structures – where was it used • Locate, manage, remove/remediate • Brief on methods etc. • • Asbestos in soils: how did it get there • Locate, manage, remove/remediate • Brief on methods etc. •
Today The World Health Organization (WHO) • estimates that 125 million people around the world are annually exposed to asbestos in the workplace, and the International Labor Organization says about 100,000 workers die each year from a related disease.
Asbestos Naturally occurring minerals which have crystallised • to form long thin fibres and fibre bundles. 90-95% of world production: Chrysotile (white • asbestos) World production peaked at 5.1 million tonnes • (1975) Asbestos is still mined and used in the developing • world – Russia, Brazil, China, India and Kazakhstan Asbestos was banned in many countries, however a • legacy of former use remains
Asbestos Mines Jeffrey mine, Quebec, Canada Troodos Mountains, Cyprus – defunct Chrysotile mine Libby mine, Montana, USA
ASBEST, Russia, ab asbestos mine on eastern slope of Ural Mountains (taken from article in New York Times 2013)
Asbestos Veins/minerals Chrysotile • fibres Crocidolite • vein
Asbestos Asbestos was banned in UK in 1999, • although there was a voluntary ban on Crocidolite in 1970 and on Amosite in 1980, with a mandatory ban on both in 1985 Like many countries there remains a legacy • of use
Worldwide Asbestos Extract taken from www.asbestos.com
Types of Asbestos 6 identified types -commercially exploited • 2 mineral groups, serpentines and amphiboles • sheet & chain silicates • Chrysotile: White Asbestos • Long, thin, flexible, inelastic & silky fibres • Amosite (Grunerite): Brown Asbestos • short needle like fibres • Crocidolite: Blue Asbestos - short needle like fibres • short needle like fibres • Anthophyllite • Straight, needle-like, flexible & elastic fibres • Tremolite • Actinolite •
Chrysotile Chrysotile is the major asbestos type in world due to; Most abundant naturally occurring, and therefore commercially mined. Initial type used (1880s) and last type prohibited in Europe (1999). Most ‘versatile’ – woven into fabrics Added to most products – cement, tiles, coatings Still used for some products in USA and other countries Still mined in Canada
Amosite Amosite asbestos in currently more commonly identified than crocidolite, but much less than chrysotile: Smaller areas of commercial exploitation (South Africa, Zimbabwe, Zambia). Acronym of Asbestos Mines Of South Africa. Voluntary import ban c1980. Used in insulating boards.
Crocidolite Crocidolite is less commonly found, due to; Voluntary import ban in 1970. Smaller areas of commercial exploitation, mainly in South Africa (2% of world production)
Health effects
Health Effects Why is Asbestos Dangerous? • Level of Exposure - Dose • (concentration / duration/ frequency) Diseases - Asbestosis • - Lung Cancer - Mesothelioma
Health Effects cont. Although asbestos is a • hazardous material, it only poses a risk to health if the asbestos fibres become airborne and are then inhaled ACMs only release • fibres into the air when the material is disturbed
Why is Asbestos Dangerous? 90 Splits into long respirable • 80 fibres 70 Long Fibres (>15µm) not • cleared from lungs 60 Cells die – release toxins • 50 East Toxins cause scar tissue • 40 West Amphiboles more resistant • 30 than Chrysotile North Amphiboles cause problems 20 • for many years 10 0 1st 2nd 3rd 4th Qtr Qtr Qtr Qtr
Can a Single Exposure Lead to an Asbestos- Related Disease? All exposures to asbestos should be avoided, however, that does not mean that you should necessarily worry about a one-off exposure. Your risk of developing an asbestos-related disease depends how much asbestos you are exposed to, for how long and on how many different occasions. A one-off short-term exposure is unlikely to be of concern, but each time you are exposed, the risk increases a little bit more – like smoking!
Asbestosis Fibrosis or scarring • Effects both lungs • Caused by inhalation of fibres • 10-20 years after exposure • Associated with high exposure over a period • of time More common in smokers • Incurable •
Lung Cancer Increased incidence of all lung cancers associated • with exposure sufficient to cause asbestosis Incidence increases with smoking and asbestos • exposure – synergistic effect individuals who are exposed to both tobacco smoke and asbestos have roughly a 30- to 50-fold increase in risk of developing lung cancer
Mesothelioma Affects lung or intestine • 20-60 year latency • No treatment • Invariably fatal • Average life expectancy 6 - 18 months • 1200 new cases each year and this figure is • on the increase
UK Asbestos Imports and Predicted Mesothelioma Deaths UK mesothelioma deaths UK Imports of asbestos 175,000 tons/year Chrysotile by 1970 3,400 deaths/ year by 2020 25,000 tons/year Amphibole by 1960 About 1,000 deaths for 1997 2040 1980 2000 2020 1960 1920 1940 Year After Peto et al 1995
Why Was It Used? Thought of as a “wonder” material • Very useful commercial properties, • Acid/Alkali resistance • Fire resistance • Thermal insulation • Mechanical strength • Sound insulation • Electrical insulator • Can be woven into textiles •
History Funeral dress for the cremation of kings • Napkins & tablecloths – Charlemagne, • ‘magic tablecloth’ Marco Polo was shown items made from • asbestos cloth on his travels Greek & Romans, slave clothing • Strengthening pots •
Variety of uses
Asbestos in the movies Wizard of Oz, poppy field snow scene • Wicked witch of the west had an asbestos • broomstick
Asbestos in Buildings
General uses • Insulating boards • Lagging • Sprayed coatings • Flooring materials • Reinforced cement products • Textured coatings • Loose insulation • Electrical insulator • Textiles
General photographs
General photographs cont.
Locate, manage, remove/ remediate Duty to manage • Assessment of presence • Assessment of work • Prevention or reduction of exposure • Duty to prevent or reduce spread •
Brief on methods HSG 264, The survey guide • Types of surveys, Management, • refurbishment/demolition HSG 248, The analyst’s guide • Methods for sampling and analysis of air • and bulk, PCOM, PLM HSG 247, The contractors guide • Removal techniques, control measures, PPE, training
Why We Need To Manage Asbestos In UK approximately 4,000 people a year • die from asbestos related diseases This is more than those associated with road traffic accidents • Within the next 25 years 50,000 • Mesothelioma deaths will occur in Britain – this equates to 150,000 asbestos deaths 25% of these people will have worked in • building trades Each week approximately 8 joiners, 6 electricians & 4 plumbers die from asbestos related diseases •
Asbestos in the ground Deliberately placed – tunnels, ducts, services, • below ground buildings, bunkers, registered and unregistered waste sites Below ground structures may remain following demolition • of original buildings Surplus material, overspray, off cuts remaining • from construction Incomplete asbestos removal prior to demolition • Building collapse or damage – fires, floods, • explosions Fly tipping • Demolition rubble, crushed and spread across site • ‘Clean’ imported material spread across site •
Sites & stockpiles
Locate, manage, remove/ remediate Cannot undertake an asbestos survey in • terms of HSG264 guidance Site investigation • Desk top site review • Surface inspection • Below surface investigation • Methodical but non-biased sampling • Asbestos screening • Asbestos quantification • Interpretation of results •
Locate, manage, remove/ remediate Decisions re licensed, non-licensed, • notifiable non-licensed activities Informed decisions regarding re-use and • associated future liabilities
Brief on methods CIRIA C733, asbestos in soils and made ground, a guide to • understanding and managing the risks HSG 248, The analyst’s guide • Methods for sampling and analysis of air and bulk, PCOM, PLM • HSG 247, The contractors guide, Removal techniques, • control measures, PPE, training Not necessarily suitable for land remediation projects e.g. 1 Monitoring needs greater detection limits e.g. SEM analysis e.g. 2 Quantification of asbestos in soils requires additional accreditation
Activity based sampling US EPA
Activity based sampling UK
Any Questions
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