Bijlage aan bulk - analyses  “vermiculite”  in opdracht van xxxxx ( company name n/a)   written   maandag 30 juni 2003

 informatie enkel ter informatieve titel / onder elk voorbehoud, en zonder enige nadelige erkentenis

Facts that places the “safe” use and “safe” fabrication of Vermiculite containing materials into question !

What is Vermiculite?                   
Vermiculite is the mineralogical name given to hydrated laminar magnesium-aluminum-ironsilicate which resembles mica in appearance.

All vermiculite ores contain a range of other minerals that were formed along with the vermiculite in the rock.

Vermiculite ores from most sources have been found to contain asbestos minerals but asbestos is not intrinsic to vermiculite and only a few ore bodies have been found to contain more than tiny trace amounts.

Vermiculite mines are surface operations where ore is separated from other minerals, and then screened or classified into several basic particle sizes. Vermiculite is found in various parts of the world.

Locations of the predominant commercial mines are in;

Australia, Brazil, China, Kenya, South Africa, USA and Zimbabwe.

How becomes a compact material a heat insulation material ?

When subjected to heat, vermiculite has the unusual property of exfoliating or expanding into worm-like pieces

(the name vermiculite is derived from the Latin 'vermiculare' - to breed worms).

 

This characteristic of exfoliation, the basis for commercial use of the mineral, is the result of the mechanical separation of the layers by the rapid conversion of contained water to steam.

The increase in bulk volume of commercial grades is 8 to 12 times,

but individual flakes may exfoliate as many as 30 times.

There is a color change during expansion that is dependent upon the composition of the vermiculite and furnace temperature.

 

Why / and How Is Vermiculite Used?
Vermiculite has been used in various industries for over 80 years. It is used in the construction, agricultural, horticultural and industrial markets.

Generic Applications -

According to the bulk sampling of vermiculite attic insulation, the asbestos content in vermiculite may be as high as 2 percent.

It therefore appears necessary that more simulations with vermiculite containing higher asbestos contents are necessary to assess the upper range of cancer risks associated with residential use of vermiculite attic insulation.

The result of analyses by PLM performed on vermiculite insulation ranged from less than 1 percent to 2 percent tremolite.

The result of the bulk analyses by electron microscopy performed on this vermiculite attic insulation ranged from non-detect to 1.54 percent actinolite/tremolite.

Vermiculite is not known to typically contain chrysotile.

 

Personal air samples were collected by two air sampling cassettes (0.8 µm) and two SKC low volume air sampling pumps, which were respectively attached to the shoulder and waist of the individual

The sampling cassettes were oriented downward and positioned within the breathing zone of the individual

The sampling pump was run for 30 minutes at the flow rate of approximately 2.1 LPM.

 

Analysis of Air Samples

Air samples were analysed by using both PCM and electron microscopy

 

The use of PCM equivalent fibers may understate the actual risk.

 

Bulk Sample of a product contained trace amounts of asbestos fibres (i.e., the laboratory reported an asbestos content of <1 percent tremolite based on PLM and <0.1 percent actinolite/tremolite based on electron microscopy)

 

• Two bags of vermiculite were opened and poured out to simulate manipulation.

 

Levels of Airborne Asbestos Fibres Detected  in a Bulk Sample

This product contained trace amounts of asbestos fibres (i.e., the laboratory reported tremolite based on PLM and <0.1 percent actinolite/tremolite based on electron microscopy

 

Airborne asbestos fibres were detected in personal air samples, stationary air samples A level of 0.10 f/cc by electron microscopy was detected in one of the stationary air samples 

 

The highest asbestos level of 0.43 fibres per cubic centimeter (f/cc) was detected by electron microscopy in one of personal air samples.

This result indicates the potential for asbestos exposure during disturbances of  vermiculite.

 

The maximum airborne concentration

of 4.3 total actinolite f/cc by electron microscopy occurred in one of the personal sampling during the first simulation with dry vermiculite.

The maximum ambient air concentration of 0.45 total actinolite f/cc by electron microscopy occurred in personal sampling (removal of the vermiculite)

 

Airborne asbestos fibres were detected in stationary air monitors on a considerable distance of the simulations, indicating the potential for asbestos fibres to migrate from source of disturbance of the vermiculite.

Detected concentrations during these simulations ranged from 0.014 to 0.37 total actinolite f/cc by electron microscopy.

 

Asbestos Levels Detected

The maximum airborne concentration

of 0.5 total actinolite f/cc by electron microscopy occurred in one of the personal sampling with dry vermiculite.

 

Two highest stationary sampled ambient air concentrations

of 0.099 and 0.099 total actinolite f/cc by electron microscopy

 

Airborne asbestos fibres were also detected in at least one of the stationary air monitors indicating the potential for asbestos fibres to migrate to a important distance of the disturbance of the vermiculite.

 

Detected concentrations ranged

from 0.0026 to 0.068 total actinolite f/cc by electron microscopy.

 

The concentrations detected in the containment system ranged

from 0.0027 to 0.24 actinolite f/cc

from 0.027 to 0.041 actinolite f/cc.

These results were used to estimate the range of potential exposure due to passive exposures to asbestos fibres migrating after disturbance of the vermiculite.

 

According to bulk sampling of vermiculite insulation in 5 bulk samples, the asbestos content in vermiculite may be as high as 2 percent

 

 

Focus on the consequences of the use of vermiculite as a heat insulator in houses.

 

Is my family at risk of exposure to asbestos if we have renovated and removed/disturbed the asbestos-contaminated vermiculite insulation? What if I have lived in a home with vermiculite insulation?

Asbestos fibres are microscopic and easily released into the air. These tiny fibres can be present in the dust in an area where asbestos-contaminated vermiculite insulation is disturbed. Therefore, it is possible that you inhaled some asbestos fibres. The amount inhaled - and the corresponding risk - will depend on how many fibres (of the respirable size) were in the air, and the time period over which you were breathing the air containing the fibres, as well as how fast you were breathing. Risks are more substantial with longer and larger exposures.

If you are concerned about having experienced a significant exposure, consult a physician who specialises in environmental or occupational medicine. It may take many years after an exposure for symptoms to develop; however, you should see a doctor if you notice any change in your breathing ability or develop problems breathing.

The preliminary results of this phase of the study indicate that exposure to asbestos is possible when vermiculite attic insulation is disturbed. The results of the initial phase of the study have enabled EPA to identify additional areas requiring further study and the agency is planning a larger scale investigation into risks. The results of the study support the agency’s existing guidance to homeowners: 1) manage asbestos contaminated material in place, 2) do not disturb it and 3) hire professionals for removal and testing

 

Do I have vermiculite insulation?

Vermiculite can be purchased in various forms for various uses. Sizes of vermiculite products range from very fine particles to large (coarse) pieces nearly an inch long. Vermiculite attic insulation is a pebble-like, pour-in product and is usually light-brown or gold in colour. The pictures below show several samples of vermiculite attic insulation.

 

 Photo - Different Grades of Vermiculite -

How does asbestos cause health problems?
Asbestos can cause health problems when inhaled into the lungs. If products containing asbestos are disturbed, thin, lightweight asbestos fibers are released into the air. Persons breathing the air may breathe in asbestos fibers. Continued exposure increases the amount of fibers that remain in the lung. Fibers embedded in lung tissue over time may result in lung diseases such as asbestosis, lung cancer, or mesothelioma. Smoking increases your risk of developing illness from asbestos exposure.

What should I do if I have vermiculite attic insulation?
DO NOT DISTURB IT.

Any disturbance has the potential to release asbestos fibers into the air. Limiting the number of trips you make to your attic and shortening the length of those trips can help limit your potential exposure. EPA and ATSDR strongly recommend that: