Where asbestos is found in the home, when and how should it be removed?

Most products made today do not contain asbestos.  Those few products made which still contain asbestos that could be inhaled are required to be labeled as such.  However, until the 1970’s, many types of building products and insulation materials used in homes contained asbestos. The automotive industry uses asbestos in vehicle brake shoes and clutch pads.  More than 5,000 products contain or have contained asbestos. U.S. Environmental Protection Agency (EPA) banned all new uses of asbestos; uses established prior to 1989 are still allowed.

Common Home Building Products that May Contain Asbestos:

  • Common products that might have contained asbestos in the past and conditions which may release asbestos fibers include: STEAM PIPES, BOILERS and FURNACE DUCTS insulated with an asbestos blanket or asbestos paper tape.  These materials may release asbestos fibers if damaged, repaired, or removed improperly.
  • RESILIENT FLOOR TILES (vinyl asbestos, asphalt and rubber), the backing on VINYL SHEET FLOORING and ADHESIVES used for installing floor tile.  Sanding tiles can release fibers.  So may scraping or sanding the backing of sheet flooring during removal. CEMENT SHEET, MILLBOARD and PAPER used as insulation around furnaces and wood burning stoves.  Repairing or removing appliances may release asbestos fibers.  So may cutting, tearing, sanding, drilling, or sawing insulation.
  • DOOR GASKETS in furnaces, wood stoves and coal stoves.  Worn seals can release asbestos fibers during use.
  • SOUNDPROOFING OR DECORATIVE MATERIAL sprayed on walls and ceilings.  Loose, crumbling or water-damaged materials may release fibers.  So will sanding, drilling, or scraping the material.
  • PATCHING AND JOINT COMPOUNDS for walls and ceilings and TEXTURED PAINTS.  Sanding, scraping, or drilling these surfaces may release asbestos.
  • ASBESTOS CEMENT, ROOFING, SHINGLES and SIDING.  These products are not likely to release asbestos fibers unless sawed, drilled, or cut.
  • ARTIFICIAL ASHES AND EMBERS sold for use in gas-fired fireplaces.
  • Also, other older household products such as FIREPROOF GLOVES, STOVE-TOP PADS, IRONING BOARD COVERS and certain HAIRDRYERS may contain asbestos. AUTOMOBILE BRAKE PADS AND LININGS, CLUTCH FACINGS and GASKETS.

How to know if it is asbestos

Despite what some fraudsters may tell you, it is not possible to identify asbestos just by looking at it.  It can only be positively identified by a person trained in fiber identification with a special polarized light microscope.  There are certified labs throughout the country that can identify asbestos in building materials (see attached list).  Contact a lab to find out how the sample should be collected and sent for testing.  It is usually not an expensive test and typically should cost about $35 per sample. Do NOT try to take samples yourself unless instructed by an asbestos expert.  You don’t want to risk exposure to the airborne fibers by disturbing it without taking the proper precautions.

Why you should Not Disturb asbestos unnecessarily

Asbestos fibers can have serious effects on your health if inhaled.  There is no known safe exposure to asbestos.  The greater the exposure, means the greater the risk of developing an asbestos-related disease. The amount of time between exposure to asbestos and the first signs of disease can be as much as 30 years.  It is known that smokers exposed to asbestos have a much greater chance of developing lung cancer than just from smoking alone. Asbestos can cause asbestosis, a scarring of the lungs that leads to breathing problems and heart failure.  Workers who manufacture or use asbestos products and have high exposures to asbestos are often affected with asbestosis. Inhalation of asbestos can also cause lung cancer and mesothelioma, a rare cancer of the lining of the chest and abdomen.  It may be linked to cancer of the stomach, intestines and rectum as well.

History of Asbestos Use & Associated Health Risks

The story of asbestos is an all-too-familiar one.  It was once considered a miraculous, do-anything natural fibre but is now identified as a serious health hazard except for one thing.  Unlike many of its doomed chemical contemporaries, asbestos is not a product of modern technology.  Its use predates history and the recognition of health hazards associated with asbestos is recorded in writings from the first century. The word asbestos comes from the Greek word meaning “inextinguishable” or “indestructible.”  However, asbestos has been known by many other names including “mountain leather,” “incombustible linen,” and “rock floss.”  The name of chrysotile, one of the most common forms of asbestos, is derived from the Greek words “chrysos” (gold) and “tilos” (fiber) or “gold fiber.” Romans used asbestos in their building materials.  Historian Pliny the Elder went so far as to note that asbestos “affords protection against all spells, particularly that of the Magi.” The Egyptians embalmed pharos with asbestos and the Persians imported asbestos from India for wrapping their dead.  They thought it was hair from a small animal that lived by fire and died by water. In medieval times Asbestos was used extensively as insulation in suits of armor. Near the end of the 19th century, the use asbestos became even more widespread as a result of the industrial revolution.  Asbestos was used in the manufacture of more than 3000 products including textiles, building materials, insulation and brake linings.  Its use continued to increase through the 1970s.  At that time the evidence against asbestos as a health hazard (it was found to cause asbestosis and mesothelioma) could no longer be denied and its use fell into sudden decline. Interestingly, the hazards of asbestos were recorded as early as Roman times.  Both Pliny the Elder and the first century geographer Strabo noted that workers exposed to asbestos had many health problems.  Pliny the Elder recommended that quarry slaves from asbestos mines not be purchased because “they die young.”  Lung ailments were common to anyone who worked with asbestos fibers.  Pliny the Elder suggested the use of a respirator made of transparent bladder skin to protect workers from asbestos dust. It is interesting that despite the evidence of severe health risks related to asbestos exposure dating as far back as the first century, the production of products containing asbestos continued to grow until the mid-1970s.  Documents reveal that asbestos manufacturers were aware of the health risks related to exposure to asbestos from the 1940s and 1950s, but chose to conceal this information from their employees.  In the 1970s, the Environmental Protection Agency (EPA) and Occupational Safety and Health Administration (OSHA) began to regulate asbestos.  Today workers are protected from exposure to asbestos as a result of very strict regulations and enforcement.  Unfortunately, legislation cannot undo the damage that was done to those who worked in asbestos related jobs prior to 1980s.


Types of Mould

Many people seek to define mould by the colour that it presents: ‘green mould’ or ‘white mould’, ‘grey mould’ or ‘brown mould’, or, even more general, ‘black mould’ versus ‘non-black mould’.  Unfortunately, the colour of a mould rarely tells you anything useful: there are harmful and non-harmful kinds of mould in each colour group.  It is difficult or impossible to determine if a mould is harmful based on what it looks like growing on a surface.

Some Common Indoor Moulds

This is a short list of the more common moulds that grow in households.  Since moulds are incredibly diverse, even within the individual species, it isn’t a complete picture, but it may help to explain why ‘black mould’ isn’t synonymous with ‘dangerous’.

(pronounced ‘clad-oh-spore-ee-um’) It can appear green, brown, grey or black on surfaces.  It can grow in many places, including walls, wood, dust and insulation.

(pronounced ‘as-per-jill-us’) It can look grey, brown, yellow, green, white or blackAspergillus can grow on walls, insulation, paper products, soil, clothing and many other places.

 (pronounced ‘pen-ih-sill-ee-um’) Penicillium is a name that often strikes people as familiar and that is because modern antibiotics were discovered thanks to a species of Penicillium long ago.  However, that doesn’t mean that the genus can’t be hazardous.  It can look blue, green, or white.  It can be found on foods, such as cheese and fruit, or in the walls, the insulation and other places.

(pronounced ‘you-low-clad-ee-um’) Usually looks black or grey and tends to grow in damp areas.  It can be found on walls, around windows, in dusty areas and other places

(pronounced ‘ack-ri-moan-ee-um’) Acremonium is often found on insulation and drywall/sheetrock, although it can be found in many other areas, too; it grows in damp places.  It can appear whitegrey or brown

(pronounced ‘stack-ee-bot-riss’) Stachybotrys is the infamous black mould that made the news in association with ill health effects many years ago.  It needs a very damp area to grow and can create toxins.  It looks black on surfaces.

(pronounced ‘all-ter-nair-ee-uh’) Alternaria looks similar to Ulocladium under a microscope.  It can appear black or grey on surfaces and has been known to cause various allergic reactions.  It can grow on walls, dusty areas, around windows, damp areas, in soil, on plants and in various other places.

Mould Myths

Myth #1: There is only one type of black mould and it’s very bad. Fact: In actuality, there are many moulds that look black.  The type of black mould that made the news years ago, associated with a lot of ill health effects, was called Stachybotrys (pronounced ‘stack-ee-bot-riss’).  However, there is a ton of other moulds that look black and are fairly common and generally not of concern.  The take-home message here is that not all black moulds are ‘bad’.

Myth #2: Only black moulds are bad.  Other types shouldn’t be worried about. Fact: A lot of people aren’t even aware that mould can be white, or orange, or blue, for instance.  The colour of a mould generally has to do with the spores it produces and has no bearing on whether it is dangerous or not.  There are some white moulds that grow on walls and other surfaces that can be just as bad as some harmful black moulds.

Myth #3: If I see mould, I should just scrub it with bleach to get rid of it. This is a complicated myth.  There are a couple of different parts to it.

  • Bleach: Bleach is generally not recommended as a fungicide (mould killer).  It works by dousing the mould in toxic levels of a chemical.  The problem is twofold: not only are humans just as susceptible to bleach’s damaging properties, but the bleach is generally a water-based solution.  In the long run, this often means that water penetrates the surface, giving moisture to the roots of the mould, which happily begin to grow again.  In the case of small patches of mould, ordinary household detergent will suffice.  It is important to make sure that the area dries quickly (ideally within 24-48 hours) so that any small bits (too small to see with the naked eye) of mould left over don’t get the chance to start growing again.
  • Is it really gone? Mould is able to grow because it has a moisture source.  Often this means that there is or was a leak or something similar involved in the first place.  Just removing the mould without fixing the water problem will usually result in the mould coming back.  Also, mould can grow behind walls in addition to just on them, so it is important to determine whether you’ve only dealt with the obvious portion of the mould, or the whole thing.

Myth #4: I can just paint over the mould to seal it up. Fact: Actually, mould can eat the paint.  Many people attempt to paint over mould only to discover that in a few months the mould has either poked its way through the paint, or the paint has started peeling off.  The mould really has to be removed before painting can be done, even if you’re using “mould-resistant” paint. Myth #5: mould and mildew are totally different things. Fact: Mildew is mould.  It’s a word that is used generally to refer to a few specific types of moulds, but it’s still all mould.

Mould Facts:

Fact #1: Mould is everywhere, no matter what you do. Bits of mould are part of the air you breathe everywhere you go.  Moulds grow on plants and in soil, float off into the air and float in through your doors and windows.  You’ve been dealing with it all your life and there is usually no way (except in very special circumstances) to create a space with no mould in the air.  

Fact #2: Large areas of mould should really be dealt with by a professional. When mould areas get larger than about 10 square feet (about a square meter) or you don’t know the extent of the problem (for instance: mould can grow behind the walls) it is important to bring in a professional who is familiar with how to deal with mould properly.  This large area usually requires extra precautions when removing mould.  Much larger areas of mould can require very complicated procedures and precautions.  Even a common, usually harmless mould can be a health issue when there is a lot of it.

Fact #3: Stains and mysterious spots are not always mould. Sometimes a black, brown, grey, or white spot isn’t actually mould.  Efflorescence, for instance, is a whitish deposit, especially on concrete, that happens when water permeates the material and leaves behind a deposit of salts.  Note, however, that in this case there is water permeation, which may mean there is mould growing where you don’t see it.  Other spots can be caused by soot or soil deposits, giving a darker colour.  If you want to know what you’re looking at, you can collect samples yourselves and send them to mould laboratories that can test air samples or pieces of material and tell you whether you have mould or not.