Increasing Awareness: Asbestos Ancient History, Characteristics, Types, Uses, Health Effects

Asbestos Definition

The word asbestos derives from a Greek word meaning “inextinguishable”

Asbestos definition

Either of two incombustible, chemical-resistant, fibrous mineral forms of impure magnesium silicate, used for fireproofing, electrical insulation, building materials, brake linings, and chemical filters.

What is Asbestos?

Natural Mineral (Rock)

Brief History

First known use: 2,500 B.C. pottery and hut insulation Greeks spun and used in cloth Used for wicks in sacred lamps Pottery

Diseases in the 1950s-1960s 1971 Asbestos listed as a hazardous air

pollutant

Characteristics

Aerodynamic

Aerodynamic

Characteristics

Aerodynamic Chemically Resistant Hydrophobic Heat resistive (1250-2000 deg. F) Flexible with High Tensile Strength

Aerodynamic Chemically Resistant Hydrophobic Heat resistive (1250-2000 deg. F) Flexible with High Tensile Strength

Characteristics continued

Size Fibers (1-5 microns, human hair is 80) Fibers>Fibrils>microfibrils

Asbestos Types

Chrysotile (white) >95% of all asbestos (white) Hair-like

Asbestos Types

Amosite (Brown) 5 % of all asbestos Needle Like

Asbestos Types

Crocidolite (blue) <1 %

Asbestos Types

Chrysotile >95% of all asbestos (white)

Amosite <5% of all asbestos (brown)

Crocidolite (blue) <1 Tremolite Anthophyllite Actinolite

Asbestos Types

Tremolite, Anthophyllite, Actinolite Little commercial value Usually a contaminant of other

asbestos or material type

Vermiculite?

Why Use Asbestos?

Heat resistive (1250-2000 deg. F) Chemically resistive Great acoustical reduction

properties Good elastic/tensile strength

properties Poor conductor of electricity Great binder

Asbestos Containing Materials

Acoustical Materials Fire proofing Heat resistive materials Ceiling and floor tile Sheet rock mud Plaster Insulation

Materials cont.

Decorative spray for texture Roof shingles, siding shingles,

sheets, etc. Mastics, glues Welding booth panels and soffits Window glazing Some paints

Health Effects

Caused by Inhalation (most likely) Ingestion Injection

Asbestos Diseases

Asbestosis (lung scarring) Lung cancer Mesothelioma (cancer of membrane

lining lungs) Pleural plaques, pleural thickening Colon, stomach, esophagus,

pancreas cancers

Respiratory Systems Defense Mechanisms

Nose, Mouth, Trachea, Bronchus, Bronchioles

Turbulent airflow Smaller pathways

Mucous Sticky layer, catches some particles

Respiratory Systems Defense Mechanisms (Continued)

Cilia Hair-like Coated with mucous and move

particles back up through bronchus Alveoli (air sacs)

O2/CO2 exchange Macrophage Cells

Macrophage Cell

Smoking/Asbestos Relationship

Asbestos-Smoking-Lung Cancer

Asbestos exposure=5X greater chance lung cancer

Smoking no asbestos exposure=10X greater chance lung cancer

Asbestos exposure of Smoker=50X greater chance of lung cancer. Newest figures now say 88X greater chance

“King of Cool” - Steve McQueen

Died of Mesothelioma in 1980 at the Age of 50

Exposed to Asbestos from Work/Hobbies Brake Pads on Cars Construction Work Ship Work

What Level of Exposure is Safe or Permissible????????

0.1 fibers per cc of air 5 f/cc, 1 f/cc, 0.1 f/cc in last 10

years

Asbestos Health Benefits

Crowds gather at Market and Laguna streets to flee the Great Fire. Building at lower center right still survives along Laguna. Almost all others pictured here burned.

Crowds gather at Market and Laguna streets to flee the Great Fire. Building at lower center right still survives along Laguna. Almost all others pictured here burned.

The 1906 San Francisco Great Fire as seen from a ferry boat in the Bay.

Closing Thought. Keep Health Effects in Perspective

Expected deaths per 100,000 Motor vehicle 1,600 Coal mining 441 Diagnostic X rays 75 Lightning 3 Hurricanes 3 Asbestos in buildings 1

Acknowledgement

Created by Larry Hagel, Industrial Hygienist, Kyron Environmental Consulting and Training

Formerly with Spokane Public Schools and a member of AASA’s Urban Healthy Schools Coalition

Email lhagel@kyronenvironmental.com AASA is dedicated to healthy school

environments, visit http://www.aasa.org/focus/