The holidays are often spent with our families and friends, giving us time to reflect on our lives together with gratitude.

But the holidays also mean that more people are traveling and spending time together indoors, sometimes in small, cramped spaces. This can greatly increase the risk of poor indoor air quality from airborne pollutants and pathogens, triggering asthma and allergies as well as exposing you to viral and bacterial infections.

But there are steps you can take to help improve your air quality and reduce your risk of exposure to air pollution and airborne infections during the holidays. Here are nine invisible challenges to holiday air quality and how you can manage them.

1. Airborne viruses

There’s inherent risk in any gathering – and beyond COVID-19 (a serious disease, often fatal, that is caused by the SARS-CoV-2 virus), other infections that easily spread in groups include:

• the common cold
• the flu
• measles
• tuberculosis (TB)

While an air purifier alone isn’t recommended for avoiding COVID-19, it’s important as a line of defense along with source control measures, such as social distancing and wearing masks (1).

While no one is saying you should be alone on the holidays, take protective measures so that you don’t put family or friends in harm’s way given the increased risk of COVID-19 and other airborne infections like influenza this winter.

What you can do:

• When possible, use video chats for get-togethers rather than meeting in person
• Consider using an Atem Desk personal air purifier as a centerpiece or near sofas and chairs in the living room

2. Winter allergies

Winter allergies can be problematic during the holidays. Pet dander, dust mites, molds, artificial scents, and indoor smoking can all contribute to miserable allergy symptoms and potentially trigger attacks in asthma sufferers (2).

Addressing allergens in the home can help mitigate symptoms for both the allergy and asthma sufferers among your family and friends.

What you can do:

• Before holiday guests arrive, clean your home with a high efficiency particulate air (HEPA) filter vacuum
• Clean pillows, beds, and mattresses
• If you have a room air purifier, be sure you’ve replaced your filter

3. Traffic pollution

To reduce the risk of COVID-19 during the holidays, avoid travel (3).Both cars and traffic are known to result in air pollution. Furthermore, air pollution has been found to increase the severity of COVID-19 symptoms(4) (5).

Traffic air pollution is a major risk for pregnant women, increasing the risk of asthma and poor lung function (6).

The Harvard Center for Risk Analysis found that pollution from traffic congestion kills 2,234 people in the U.S. every year.

What you can do:

• Run an air purifier, if you live by highways
• Invest in a car air purifier device like the Atem Car
• To reduce air pollution, select vehicles that are fuel efficient, hybrid or electric vehicles

4. Cooking and cleaning

With out-of-town guests and holiday celebrations taking place in the home, there’s bound to be an increase in household cleaning and cooking.

All human activity in buildings, especially cooking and cleaning, can release particulates, gases, chemicals, and odors into the atmosphere, including (7):

• harmful cleaning chemicals found in air fresheners
• chlorine bleach
• furniture and floor polish
• rug and upholstery cleaners
• oven cleaners
• aerosol spray products
• detergents
• dishwashing liquid
• ammonia, found in many cleaners

Charcoal briquets used for cooking or heating can also release particulates that are linked to heart and lung conditions (8).

What you can do:

• Purchase green or eco-friendly cleaning products with few volatile organic compounds (VOCs), fragrances, irritants, and flammable ingredients
• Use warm water and soap or baking soda as a safer cleaning solution
• Avoid petroleum-based lighter fluids and self-lighting charcoal
• Cook without grills or barbecues, if possible

5. Wood-burning fireplaces and stoves

A crackling fire on a frosty night has traditionally been the preferred way to keep warm during long, cold winters, especially in regions where forms of indoor heating like furnaces aren’t available. But studies have determined that wood burning in fireplaces and stoves can result in extremely poor air quality (9).

Wood fires are also connected to a range of health conditions (10) (11). The American Lung Association has found that health threats linked to wood burning can include (12):

• coughing
• wheezing
• asthma attacks
• heart attacks
• lung cancer
• premature death

Wood-burning emissions also release particle pollution, carbon monoxide, nitrogen oxides, and VOCs as well as add carbon dioxide and methane to the atmosphere, both of which are major contributors to climate change (13).

Despite regulatory efforts to curb wood stoves and fireplace use, wood burning is an essential means of heating homes in a number of regions around the world.

Air pollution from wood burning is still a major concern even in Western countries where other types of heating are available. In the United States, for example, the Census Bureau found that ten counties with populations over 65,000 relied on wood for between 16.6 and 60.6 percent of their heating (14).

An additional nine counties in Arizona, California, Maine, Massachusetts, New Hampshire, New Mexico, Oregon, Washington with populations under 65,000 also had similar percentages of wood-burning homes.

What you can do:

• Try to find alternatives to burning wood
• If you must burn wood, use wood that has been split, dried, and covered for six months
• Use a HEPA filter in your fireplace, if possible
• If you’re going to use a fireplace, use it sparingly with an air purifier running
• Power your heating mechanisms, such as furnaces, with a clean, renewable resource when possible, like solar power
• Find a fireplace video, put on some holiday music, and enjoy breathing fresh air
• Stay up to date on your community’s air quality with an air quality monitor

6. Scented candles & fragrances

If you’re looking brighten your holidays with scented candles or artificial fragrances, you may want to think again. Scented candles present hidden dangers even when they’re not lit.

Many candles are made of paraffin wax and use synthetic fragrances and dyes. Paraffin is a petroleum byproduct. When burned, paraffin wax releases VOCs and ultrafine particles.

Scented candles usually use synthetic fragrances and dyes that can emit VOCs whether the candle has been lit or not (15).

What you can do:

• Simmer cinnamon sticks, cloves, and nutmeg in a pot of water on your stove
• Diffuse essential oils (not fragrance oils that contain artificial ingredients)
• Place potpourri bowls around your home

7. Christmas tree syndrome

Tightly-bound trees accumulate moisture and can become a breeding ground for molds. These molds enter your home when the tree is brought indoors and can spread mold spores as long as the tree remains indoors.

This can result in “Christmas Tree Syndrome,” an allergic reaction caused by any of the 53 types of mold found on the bark and needles of Christmas trees. A 1970 study published in the Canadian Medical Association Journal found that 7 percent of allergy sufferers were allergic to conifers (16).

What you can do:

• If you plan to keep the tree, buy preventative medication for allergies
• Put the tree up later in the season to reduce exposure time
• Keep the tree in a cold area of the home to prevent mold growth
• Place the tree outdoors within view from indoors
• Decorate the house with ornaments and lights rather than with a tree
• Use a room air purifier for allergies

8. Indoor plants

You may want to brighten your home with indoor plants for the holidays. You may have even heard that plants can clean your indoor air. But what’s the truth about plants and indoor air quality?

Some popular research around this topic seems promising. A 1989 NASA report suggests that VOCs could be removed by plants in airtight laboratory conditions, finding that 10 to 90 percent of benzene, trichloroethylene, and formaldehyde was removed from the air within 24 hours. A 2017 study focused on ozone reduction suggested .9 to 9 percent of ozone was removed by a leaf surface area to room volume ratio of 0.06 m-1(17).

While these studies may seem like good news, there’s a problem. Our homes aren’t airtight. The air in many homes and offices completely swaps out at least once every hour. To get the same air cleaning power from a plant as in the 2017 study to keep up with this air turnover, you’d need 80 plants in a 500 square-foot room. And while plants can remove VOCs in small amounts, you’d need 1,000 plants in a 10x10x8-foot room to match the air filtration potential outlined in the NASA study (18).

Introducing new plants into a home can also risk exposing both humans and pets to allergies, in particular if the plant is toxic to a cat or dog.

What you can do:

• If safe for pets and animals, enjoy plants for their appearance
• Grow plants outdoors for appearance, food, and seasoning
• Use an air purifier for gases and odors rather than relying on indoor plants

The takeaway

The holidays are meant for relaxation and time spent with family – addressing some of the holiday season’s biggest air quality challenges can allow you to put your feet up and enjoy the comforts of home without irritants, pollutants, or pathogens clouding your indoor air.

You’ll breathe easier knowing that you’ve helped make your home cleaner and safer for your family members and loved ones.