It will depend on the size and composition of the dust and fibres. Large dust particles and fibres will mostly be captured in your nose and throat. They can also get in your eyes and fall on your skin. These larger particles can irritate your eyes, nose, throat and skin. This can cause cough, runny nose, and itchy eyes, nose and skin but this will only be for the short-term.
Very fine dust can be generated when you are sawing, cutting, grinding and scraping, particularly if you are using power-tools. The finer dust, which is invisible to the naked eye, can get deep into your lungs. This may cause some breathing problems, particularly if you have an existing respiratory disease, such as asthma, and are sensitive to dust.
Some dusts and fibres can be dangerous if they contain certain chemicals or compounds, such as asbestos, respirable crystalline silica, lead, formaldehyde or mould. These are discussed below.
Asbestos
Asbestos was used widely in building materials up until the mid to late 1980s. Many homes that were built before 1990 will still contain asbestos materials and products. These include walls, roofs, fencing, eaves, and insulation (although asbestos was not used widely as roof insulation in WA).
Asbestos can cause some cancers, such as mesothelioma, lung, laryngeal and ovarian cancer, and asbestosis. There is no known safe level of asbestos exposure and therefore you need to try to avoid any exposure to fibres; however, if you have been exposed it doesn’t mean you will get disease. There are strong regulations for the removal of asbestos. For homeowners the relevant regulations are the Health (Asbestos) Regulations (external site). If your house was built before 1990 and you are unsure if it contains asbestos, you should either check with an expert or treat any material you are going to work with as asbestos and follow the regulations.
You should never grind, sand or use power tools on material that might contain asbestos. If you do accidentally use power tools, on material that you later discover contained asbestos, it does not mean that you will develop an asbestos related disease. Asbestos related diseases do not commonly occur without multiple exposures over several years.
Respirable crystalline silica
Silica is found in many common construction materials including, brick, cement, concrete, drywall, grout, and tile. The products with the highest silica content are engineered stone benchtops. Silica in construction material is not a problem until it is cut or ground to create very fine particles [respirable crystalline silica (RCS)] that can be breathed into your lungs.
Respirable crystalline silica can cause lung cancer and a lung disease called silicosis. Unlike asbestos, silica is still mainly an occupational exposure problem and most cases of silicosis, and silica-related lung cancer, are due to long-term and/or repeated high exposures in the workplace. However, home renovators still need to be cautious when cutting or grinding material such bricks, concrete and engineered stone.
Lead
Before 1970, paints containing high levels of lead were used in many Australian houses. Lead was phased out of paint from that time, although it is still present in trace amounts. As with any of the substances mentioned here, lead in house paint is a problem only if it is disturbed and can be either breathed in or eaten/swallowed. Flaking lead-based paint can be a problem, particularly for children who may purposefully or accidentally put the flakes in their mouth. Sanding lead paint can be a problem as it will create fine dust that can be breathed in.
Lead can cause immediate (acute) and long-term (chronic) health effects.
Wood dust and formaldehyde
Both natural wood and composite wood products will generate fine dust when cut or sanded. Composite wood products are made of strands, particles, fibres, or boards of wood held together with glues. These products are commonly used in the manufacture of furniture, cupboards, flooring, and wooden children’s toys. The glue, or resin, that is used in composite wood products contains formaldehyde. Formaldehyde is also a naturally occurring chemical in wood
Both wood dust and formaldehyde, independently, can cause health problems. High levels of wood dust can cause cancers in the nose, as can formaldehyde. Again, these cancers occur predominantly in people who work with wood and composite wood products and, therefore, have long-term exposure. Short-term exposures to either wood dusts or formaldehyde can cause irritation of the eyes, nose, and throat, coughing, wheezing, nausea, and skin irritation.
Man-made mineral fibres (MMMF)
A lot of insulation material is made from various MMMF, like fibreglass and mineral wool. Over timeinsulation can break down and deteriorate. This happens from normal wear and tear and if animals nest in your roof space. Therefore, fibres and particles can come loose and airborne if disturbed.
There is not strong evidence that MMMF are carcinogenic, even with high occupational exposures, and they do not seem to cause other lung disease in workers. Risk of disease from MMMF insulation in the home is therefore extremely low. However, some people may find that these fibres can irritate the skin, eyes and throat.
Other biological dusts
Accumulated dust in hidden spaces may contain mould spores, animal dander, plant pollen and other materials from the local environment that can cause irritation of eyes nose and throat when released into the air during a renovation.