Climate Change, Indoor Air Quality and Ventilation
Most Canadians spend a significant portion of their time indoors. As we work to address climate change, one of the actions we can take is to improve the energy efficiency of our homes through adding insulation and sealing air leaks through caulking, weather-stripping, and other weatherization measures. Taking these positive steps should be accompanied by an understanding of the importance of proper ventilation as well, to protect our health.
Take appropriate ventilation actions when using the following:
- Gas ranges and space heaters. Use a range hood or fan to draw contaminated air outdoors directly at the source where possible. Opening a window slightly will improve indoor air quality, but will result in slightly lower home energy efficiency.
- Open wood fireplaces. Ensure sufficient fresh air intake into the home through opening a window slightly to enable smoke and particulates to leave the home through the chimney.
- Home improvement activities. Painting, paint stripping, welding, sanding, or using pesticides cause indoor air pollution. Conduct these tasks outside where possible, or open a window during these activities. Consider choosing low-emission paints and varnishes.
- Avoid smoking indoors, or open a window while smoking to avoid the health impacts of second-hand smoke.
Advanced designs of some new homes, or renovated homes, may feature mechanical systems that bring outdoor air into the home, through heat recovery ventilators. These units maximize the energy efficiency of bringing fresh outdoor air into the home by transferring the heat from the outgoing air.
It’s important to ventilate bathrooms and kitchens to prevent mould growth, which has respiratory and allergy-related health impacts. Too much humidity in a well-sealed home can also cause mould growth. And as flood risks grow with climate change, we will see more danger from mould growth in affected homes. Use kitchen and bathroom exhaust fans when cooking and showering. More information is to come when we spotlight mould in December.
Radon gas forms naturally in the ground and can seep into buildings. Exposure to high levels over the long-term is a leading cause of lung cancer in Canada. Testing your home for radon is the only way to know if you are being exposed to high levels – and is particularly important as homes becomes increasingly well insulated and energy efficient. Find out more in November’s focus on radon.
Take Action on Radon
Radon is a naturally-emitted radioactive gas that enters buildings by seeping in through cracks in foundations, pipes and windows. It forms naturally through the breakdown of uranium in the ground.
• Radon is colourless, odourless and tasteless
• Radon is the second leading cause of lung cancer in Canada, causing an estimated 3,000 deaths a year
• 16% of lung cancer deaths in Canada are from radon
Radon levels can vary from house to house. Health Canada recommends that all Canadians test their homes. Workplaces, schools and daycares should also be tested.
Radon test kits are found in Home Depot and Home Hardware stores across Canada, and at a number of speciality suppliers, listed here.
When purchasing a radon test kit, be sure that it is a long-term test kit (one that measures radon levels in your home for at least 3 months). Also, find out if the purchase price includes shipping and laboratory analysis fees.
If your radon results are above the Canadian guideline, the problem can be fixed for a reasonable cost. Depending on the test results, sealing cracks in the foundation of your home could be a solution. The most common and effective solution is the installation of an active soil depressurization system (seen left). This system draws the radon from below the building to the outside to stop it from entering the building and reduces radon levels by over 90%. Be sure to contact a certified radon mitigation professional to help you.
Only a small percentage of Canadian homes and buildings will have radon levels above the guideline.
Having a staff meeting? November is Radon Awareness Month. Ask for 5 minutes on the agenda to talk about radon, and use material from our three-slide PowerPoint presentation!
Health Canada has supported outreach on radon for several years and works with partners to provide online information.
Read about people who have suffered from the health effects that undiscovered radon build up can cause:
- ‘There was no clue’: Woman certain radon found in basement caused her lung cancer from CBC
Visit Take Action on Radon.
Mould & Health
As we make our homes and workplaces more energy efficient to address climate change, we may decrease air circulation, which in some cases can lead to mould growth.
Health Canada considers indoor mould growth to be a significant health hazard. Mould can grow behind walls or above ceiling tiles where it is hard to see, so it is important to check for the presence of mould anywhere that is damp and especially where water damage has occurred. Unless the cause of the moisture problem has been identified and solved, mould will reappear.
In order to grow, mould needs moisture and a material it can live on. It then releases spores into the air, which are tiny particles that people can actually breathe in. Breathing in these spores and the by-products they produce can negatively impact our health. Living in homes with mould and damp conditions increase the risk of respiratory symptoms such as eye, nose and throat irritation, coughing and phlegm build-up, wheezing and shortness of breath and worsening of asthma symptoms.
Mould can cause:
Any type of fungi that grows on food or damp materials is commonly known as mould. Black mould refers to a specific type of mould that can be various colours regardless of the name. Mildew also refers another type of mould. Regardless of the type, Health Canada recommends that all moulds need immediate attention.
Anything that can get wet! This includes carpets, books, mattresses and pillows, toys, bathrooms, furniture, walls, ceilings, etc.
Mould thrives in damp, warm and humid environments. Common sources of moisture that lead to mould growth include:
It is important to take preventative measures to ensure your home does not host the ideal conditions for mould or for mould to continuously return. Take these steps to prevent damp, and moulds from thriving.
1. Keep humidity level low:
Cracking open windows while showering or bathing, washing clothes or cooking.
Use bathroom and kitchen fans and ensure they are operating correctly and use them. To ensure your fans are operating lift your hand up to the fan to ensure there is a decent airflow.
2. Fix leaks or infiltration
3. Dry wet areas within 48 hours
4. Clean up any mould you find following proper procedure
It is important to determine the extent of the mould problem in your home to help you decide on the clean-up procedure. Many small patches of mould in one area or throughout your home are a sign of moisture problems that need to be investigated and corrected right away. If you live in an apartment it is your landlord’s duty to hire professionals in the case of medium to large mould areas.
An area of mould is considered small if it covers one square metre or less (seen left). There should be no more than three patches of mould, with the total area staying within one square metre. Small areas of mould need to be cleaned up using proper procedures and protective equipment. If ignored, small mould areas may become larger over time, to it is important to clean them up before the problem gets larger.
The area of mould is considered medium if there are more than three patches of mould (each patch smaller than a square metre), but the total area is less than three square metres (seen left). In this case, assessment by a qualified professional is recommended but in most cases, a medium amount of mould may be cleaned up using proper procedures and protective equipment.
An area of mould is considered large if a single patch of mould is larger than three square metres (seen left). Health Canada does not recommend that an unqualified person clean up large areas of mould. You may need a professional assessment to determine why the mould is there in the first place and how to clean it up.
Having a staff meeting? Ask for 5 minutes on the agenda to talk about mould, and use material from our three-slide PowerPoint presentation!
Climate Change, Bug-Transmitted Diseases and Health
In North America, mosquitoes are often associated with carrying diseases over great distances. With climate change, mosquitoes and other vectors – organisms that can transmit disease to humans or animals – such as ticks, flies and fleas are increasingly carrying infectious diseases further north.
Scientists agree that the effects of climate change will include more sporadic and irregular precipitation, with longer periods of drought separated by more intense rainfall; and increasing average temperatures. These conditions may enable vectors – and the diseases they carry – to extend their populations and increase their ranges. This, in turn, will increase the chances that humans contract vector-borne diseases.
This month, the Healthy Communities focuses on two important vector-borne diseases for Canada; Lyme Disease and West Nile Virus. Understanding common symptoms and taking simple, preventative steps can greatly reduce your chances of contracting them.
Infected black-legged ticks (also known as deer ticks) can transmit Lyme Disease to people through bites. Black-legged ticks are most often found in (but are not limited to) forests, wooded areas, shrubs, tall grass and leaf piles.
Information on areas designated as risk areas by the Public Health Agency of Canada is available here. However, it is important to note that infected ticks can also exist outside of these areas.
While symptoms of Lyme disease can vary, early signs typically occur 3 to 30 days after a bite by an infected tick. These may include: rash (sometimes shaped like a bull’s eye), fever, chills, headache, fatigue, and muscle and joint aches.
If left untreated, more severe symptoms may occur and can last from months to years; including severe headaches, additional skin rashes, facial paralysis, intermittent muscle, joint, tendon and bone aches, heart disorders, neurological disorders, and arthritis.
How To Protect Yourself
When spending time outdoors, you can take important precautionary steps:
- Wear clothing that covers exposed skin, such as long-sleeved shirts and long pants, and tuck your socks into your pants
- Use bug repellent, especially around your wrists, ankles and neck
- Stay on trails or paths to avoid long brush or grasses
- Check your body for ticks once you return indoors
- If bitten, remove the tick safely – instructions from the Government of Canada are available here.
Infected mosquitoes can pass virus that causes West Nile from birds to humans.
Symptoms can include headaches, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis. In extreme cases, West Nile Virus can result in fatal neurological disease.
However, only about 20% of people who are infected will develop severe symptoms, which appear 3 to 14 days after infection. Elderly people and those with impaired immune systems are at a highest risk of contracting symptoms.
How To Protect Yourself
You can take steps the following steps to protect yourself from mosquito bites:
- Use bug repellent, especially around your wrists, ankles and neck
- Wear clothing that covers exposed skin, such as long-sleeved shirts and long pants
- Install window screens
- Reduce mosquito habitat around your home by regularly emptying containers that may hold water, such as buckets, children’s pools or bird baths
Related News Articles
Climate Change, Air Quality and Health
Unhealthy air comes from cars and trucks, some industries and power plants, and construction equipment, to name a few sources. Natural sources like wildfires and dust also contribute to air pollution.
Depending on the length of time you are exposed, your health status and genetic background, and the concentration of pollutants, air pollution can have a negative effect on your heart and lungs. It can make it harder to breathe, irritate your lungs and airways, and worsen chronic diseases such as heart disease, chronic bronchitis, emphysema and asthma.
The Air Quality Health Index (AQHI) is a scale developed by governments to help Canadians protect their health.
The AQHI used by the Government of Canada updates the air quality status for most cities across Canada and forecasts future maximum air quality conditions:
Find out your local Air Quality Health Index conditions here
Use the new AQHI Canada App to stay informed about outdoor air quality, plan your outdoor activities and receive alerts to find the best time to be active outdoors. Using this tool can help you protect your health by limiting exposure and adjusting outdoor activity levels during increased levels of air pollution. (Source: Air Health Check).
Download the AQHI Canada App for Android, iPhone, and iPad, or check your local forecast and AQHI conditions online at www.theweathernetwork.com.
Poor air quality affects us differently. Learn more here about those who may be at a higher risk:
- Young children
- Existing respiratory conditions
- Existing cardiovascular conditions
- Exercise or play sports outdoors
- Do strenuous work outdoors
*You may also notice symptoms if you are not in one of these groups if the air quality risk is high.
The following table provides the health messages for ‘at risk’ individuals and the general public for each of the AQHI Health Risk Categories:
Symptoms that may indicate an exposure to poor air quality include coughing or wheezing, difficulty breathing, sore throat, and irritated nose and eyes. Here are some suggestions on protecting your health:
- Time your exercise or activities for cooler times if possible, such as early morning or evening
- Drink lots of water, take lots of breaks, and modify your activity level if you feel any symptoms
- If you are someone who may be at a higher risk, talk to your health care professional about protecting your health when air pollution levels are high
- Consider the location of your activity and if possible, stay active indoors if cooler and away from traffic
Related News Articles
Climate Change, Extreme Weather and Health
As our climate changes, extreme weather events occur more frequently and with more intensity. Understanding how these weather events can affect your health is a first step towards taking protective action. For example:
Periods of extreme heat can trigger cardiovascular and respiratory disease, and in some cases can be fatal. Elderly populations are especially vulnerable – and factors including housing conditions, availability of air conditioning, and general health can also play a role.
What you can do: protect yourself from the heat!
- Plan ahead to keep cool: The best defence against heat -related illness is prevention — stay cool inside an air conditioned building, even if it is just for a couple of hours a day. If your home does not have air conditioning, choose other places that you can go to get relief from the heat (e.g., shopping malls, libraries or theatres). Timing is key: If you must be outside, limit your activities and don’t plan to do them during the warmest part of the day (between 11 am and 4 pm).
- Water intake: Increase your water intake even if you don’t feel thirsty (and be aware that alcoholic drinks are dehydrating).
- Dress for heat: Wear lightweight, light-coloured clothing. Protect your face and head by wearing a wide-brimmed hat. Don’t forget to wear sunscreen!
- Listen: Listen to weather reports for “Humidex Advisories” issued by Environment Canada, and avoid unnecessary outdoor activities when the humidex is above 40˚C. Advisories are issued when temperatures are expected to exceed 30˚C, and when humidex values are expected to exceed 40˚C.
FYI: Humidex is a measure of how hot we feel, taking into account the combined effect of temperature and humidity.
Flooding is predicted to become a greater threat to communities across Canada, as rainfall becomes more intense and more irregular. In addition to damaging buildings and infrastructure, flooding impacts our water supply systems through an increase in stormwater runoff and sewer overflows. When sewer overflows occur, harmful pollutants (including pharmaceuticals, flame retardants, and heavy metals such as cadmium, lead, mercury, silver, and zinc), as well as bacteria, viruses and other pathogens, can make their way into lakes and rivers and can pose serious risks for human health. This increases the burden on drinking water treatment facilities, and can make water bodies unsuitable for recreational activities.
What you can do: reduce runoff and watch what you flush
- Redirect your downspout: Help reduce stormwater overflows and runoff by connecting your downspout to a rain barrel or allow it to drain to a permeable surface.
- Increase permeable surfaces: Choose permeable surfaces for driveways and walkways (this minimizes flash floods and stormwater runoff) such as gravel, wood chips, punctured concrete, or porous forms of concrete.
- Watch what you flush: Learn what shouldn’t go down the drain and take the “I don’t flush” pledge at idontflush.ca
Links and Resources
• Health Canada extreme heat information: https://www.canada.ca/en/health-canada/services/environmental-workplace-health/reports-publications/climate-change-health/communicating-health-risks-extreme-heat-events-toolkit-public-health-emergency-management-officials-health-canada-2011.html#a1.1
• US Center for Disease Control extreme heat information: https://www.cdc.gov/climateandhealth/pubs/extreme-heat-final_508.pdf
• Pollution Probe Primer on Climate Change and Human Health: https://www.pollutionprobe.org/publications/primer-on-climate-change-and-human-health/
• Pollution Probe Great Lakes Fact Sheet #12: Wastewater Management: https://www.pollutionprobe.org/publications/great-lakes-fact-sheet-12-wastewater-management/
• I don’t flush campaign: http://idontflush.ca