Lead & Crystalline Silica Page

Quebecers have been aware of the harmful health effects of asbestos dust for years now, but there’s another deadly dust on the horizon: crystalline silica dust.

What is crystalline silica?

Quartz is a form of crystalline silica. The most common mineral in the world, it’s found in all forms of rock, including sand. Silica isn’t considered a health risk when it’s amorphous (inert), but when it’s released into the air in the form dust, after shattering, cutting or polishing marble, concrete, stone, granite, brick, mortar or any other material that contains it, it can easily be breathed deep into the lungs. The dust is so fine that it’s only visible under a microscope.

After asbestos, crystalline silica is the second most identified cause of death due to toxic dust inhalation and has been for the past ten years. A form of occupational lung disease, like occupational asthma and asbestosis, silicosis is irreversible and can lead to disability and/or death.    

Just because you don’t see anything in the air and there isn’t a cloud of dust around a worker doesn’t mean silica isn’t present. So, if you’re going to be doing work that requires demolition with a jackhammer — or the breaking, crushing, piercing, sawing, sanding and grinding of concrete or masonry structures — proper dust control and protection measures have to be taken.

Lead-based paint

Are you worried about the deterioration of paint in or on a building that was built before 1978? You should be, as it could contain lead.

What is lead-based paint?

A highly toxic metal that was used in paint before 1978, lead was originally incorporated into paints because of its water resistance, durability, washability, and capacity to make them opaque. Ingesting or breathing lead-based paint can cause a myriad of health effects, including neurological and behavioural problems in exposed children. Even though it was banned in paint in 1978, it’s found in buildings that were built before the ban.

Where is lead generally found?

High levels of lead are usually found in brightly coloured paints, like yellow and orange, because they require the use of lead-chromate pigments. High levels of lead are also found in white paints, as well as houses built before 1950. Homes that were built after 1990 shouldn’t contain any lead, because most paint manufactured for the general public in Canada and the United States barely contained any by then.

Windowsills and the nooks and crannies around windows are among the highest risk areas because of the amount of friction and contact that occurs when windows are opened and closed. Over time, this friction can cause the rapid deterioration and peeling of paint, faster than in other areas of the home. Another reason windowsills are particularly dangerous is how accessible to children they are.

Why is lead so dangerous for children?

Children under the age of six are most vulnerable to lead poisoning. The reason why is because lead is absorbed into the bones before it spreads to the rest of the body. Once spread, lead can cause irreversible neurological damage that reduces cognition in adulthood. Another reason kids are so vulnerable is their tendency to put things in their mouths, including lead dust, and even the smallest amounts of dust containing lead are dangerous for infants and children. Lead that’s absorbed by the mother while pregnant can also cause harm to the unborn child. We now know there’s no safe level of lead exposure.

Where is lead-based paint most commonly found?

Some residential, commercial and institutional buildings could have walls covered with lead-based paint. If the paint is peeling, coming off or deteriorating because of normal use (on doors, windows, stairs and ramps) or construction work, you and your children could be exposed to serious health hazards like anemia (a deficiency of red blood cells), which is one of the effects of lead poisoning along with brain and nervous system damage.

If you want to know if your house contains lead-based paint, you can send samples of the paint to a laboratory for analysis, or hire a contractor with analytical x-ray equipment to determine the elemental composition of painted surfaces, to detect lead.