Introduction to asbestos Presented by Jane Tierney July 2015 - PowerPoint PPT Presentation

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