Wildfires: How to cope when smoke affects air quality and health
As wildfires become more frequent due to climate change and drier conditions, more of us and more of our communities are at risk for harm. Here is information to help you prepare and protect yourself and your family.
How does wildfire smoke affect air quality?
Wildfire smoke contributes greatly to poor air quality. Just like fossil fuel pollution from burning coal, oil, and gas, wildfires create hazardous gases and tiny particles of varying sizes (known as particulate matter, or PM10, PM2.5, PM0.1) that are harmful to breathe. Wildfire smoke also contains other toxins that come from burning buildings and chemical storage.
The smoke can travel to distant regions, carried by weather patterns and jet streams.
How does wildfire smoke affect our health?
The small particles in wildfire smoke are the most worrisome to our health. When we breathe them in, these particles can travel deep into the lungs and sometimes into the bloodstream.
The health effects of wildfire smoke include eye irritation, coughing, wheezing, and difficulty breathing. The smoke may also increase risk for respiratory infections like COVID-19. Other possible serious health effects include heart failure, heart attacks, and strokes.
Who needs to be especially careful?
Those most at risk from wildfire smoke include children, older adults, outdoor workers, and anyone who is pregnant or who has heart or lung conditions.
If you have a chronic health condition, talk to your doctor about how the smoke might affect you. Find out what symptoms should prompt medical attention or adjustment of your medications. This is especially important if you have lung problems or heart problems.
What can you do to prepare for wildfire emergencies?
If you live in an area threatened by wildfires, or where heat and dry conditions make them more likely to occur:
- Create an evacuation plan for your family before a wildfire occurs.
- Make sure that you have several days on hand of medications, water, and food that doesn't need to be cooked. This will help if you need to leave suddenly due to a wildfire or another natural disaster.
- Regularly check this fire and smoke map, which shows current wildfire conditions and has links to state advisories.
- Follow alerts from local officials if you are in the region of an active fire.
What steps can you take to lower health risks during poor air quality days?
These six tips can help you stay healthy during wildfire smoke advisories and at other times when air quality is poor:
- Stay aware of air quality. AirNow.gov shares real-time air quality risk category for your area accompanied by activity guidance. When recommended, stay indoors, close doors, windows, and any outdoor air intake vents.
- Consider buying an air purifier. This is also important even when there are no regional wildfires if you live in a building that is in poor condition. See my prior post for tips about pollution and air purifiers. The EPA recommends avoiding air cleaners that generate ozone, which is also a pollutant.
- Understand your HVAC system if you have one. The quality and cleanliness of your filters counts, so choose high-efficiency filters if possible, and replace these as needed. It's also important to know if your system has outdoor air intake vents.
- Avoid creating indoor pollution. That means no smoking, no vacuuming, and no burning of products like candles or incense. Avoid frying foods or using gas stoves, especially if your stove is not well ventilated.
- Make a "clean room." Choose a room with fewer doors and windows. Run an air purifier that is the appropriate size for this room, especially if you are not using central AC to keep cool.
- Minimize outdoor time and wear a mask outside. Again, ensuring that you have several days of medications and food that doesn't need to be cooked will help. If you must go outdoors, minimize time and level of activity. A well-fitted N95 or KN95 mask or P100 respirator can help keep you from breathing in small particles floating in smoky air (note: automatic PDF download).
About the Author
Wynne Armand, MD, Contributor
Dr. Wynne Armand is a physician at Massachusetts General Hospital (MGH), where she provides primary care; an assistant professor in medicine at Harvard Medical School; and associate director of the MGH Center for the Environment and … See Full Bio View all posts by Wynne Armand, MD
The cicadas are here: How’s your appetite?
You’ve probably heard the news: Cicadas are coming. Or — wait — they’re already here.
And are they ever! Due to an unusual overlap of the lifecycles of two types (or broods) of cicadas, trillions of cicadas are expected to emerge in the US by the end of June, especially in the Midwest.
If you’d like to see where they’ve already arrived, track them here. And if you’re wondering if this cicada-palooza could help with grocery bills, read on to decide for yourself how appealing and how safe snacking on cicadas is for you. The pros and cons could change your outlook on the impending swarm.
What to know about cicadas
Don’t worry, cicadas are largely harmless to humans. In fact, their appearance is welcome in places where people routinely snack on them as a low-cost source of calories and protein.
Estimates suggest up to two billion people regularly eat insects, especially in South and Central America, Asia, Africa, Australia, and New Zealand. Cicadas, when available, are among the most popular. And if you thought no one in the US eats cicadas, check out this video from a May 2024 baseball game.
Are you tempted to eat cicadas?
For plenty of people, cicadas aren’t the food of choice. Some people can’t get past the idea of eating insects as food. That’s understandable: after all, the culture in which we are raised has a powerful influence on what we consider acceptable in our diets. Something some Americans might find off-putting (such as eating snakes) is common in China and Southeast Asia. Meanwhile, people outside the US find aspects of the typical Western diet unappealing (such as root beer, peanut butter and jelly, and processed cheese).
But some people shouldn’t eat cicadas because it could be dangerous for them.
Why you should — or shouldn’t — eat cicadas
Eating cicadas is common in many parts of the world because they are
- nutritious: cicadas are low in fat and high in protein, including multiple essential amino acids
- inexpensive or free
- tasty (or so I’m told): descriptions of their flavor vary from nutty to citrusy to smoky and slightly crunchy.
In years when cicadas emerge, recipes for dishes containing cicadas emerge as well.
Then again, there are several good reasons to avoid making cicadas a part of your diet, including these:
- You just can’t get past the “ick” factor. Adventurous eaters may be willing to try or even embrace consuming cicadas, while others will be unable to view the idea as anything other than horrifying.
- You find the taste or consistency unappealing.
- You’re “cicada intolerant.” Some people get stomach upset, nausea, or diarrhea if they eat too many cicadas.
- You’re pregnant or breastfeeding, or are a young child. Concerns about even low levels of pesticides or other toxins in cicadas have led to recommendations that these groups not eat them. Doesn’t this suggest the rest of us should also steer clear? Well, thus far, at least, there’s no evidence that toxins in cicadas are causing health problems.
But there is one more very important entry on this list: people with a shellfish allergy should not eat cicadas. Odd, right?
The shellfish-cicada connection
Cicadas are biologically related to lobsters, shrimp, crabs, and other shellfish. So if you’re allergic to shellfish, you might also be allergic to cicadas. A particular protein called tropomyosin is responsible for the allergy. It’s found in shellfish as well as in many insects, including cicadas.
The allergic reaction occurs after eating the cicada. Just being around them or handling them won’t trigger a reaction.
Among people with a shellfish allergy, developing a reaction after eating cicadas could be a bigger problem than it seems: up to 10% of people have shellfish allergies and, as noted, insect consumption is common worldwide.
Is it okay for your dog or cat to eat cicadas?
Walking your dog after the emergence of cicadas can be a new and exciting experience for you and your pet! Dogs may chase after cicadas and eat them. Cats might, too, if given the chance. That can be a problem if your pet eats too many, as some will experience stomach upset or other digestive problems.
While the insects are considered harmless to dogs, the American Kennel Club says it’s best to steer them away from cicadas once they’ve eaten a few.
Which other insects trigger allergies?
While insect-related allergic reactions (think bee stings) and infections (like Lyme disease) are well known, the insect-food-allergy connection is a more recent discovery.
One recently recognized condition is the alpha-gal syndrome, in which a person bitten by certain ticks develops an allergy to meat. The name comes from a sugar called galactose-α-1,3-galactose (or alpha-gal) found in many types of meat including beef, lamb, pork, and rabbit. According to the CDC, up to 450,000 people in the US may have developed this condition since 2010.
There aren’t many rigorous studies of the overlap of insects and food allergies, so there are probably others awaiting discovery.
The bottom line
When it comes to eating cicadas, I’ll pass. It’s not because of the risks. I’ve never had a problem with shellfish, and for most people the health risks of eating cicadas seem quite small. It’s just unappealing to me, and I’m not a particularly adventurous eater.
But let’s go easy on those who do enjoy snacking on cicadas. Insects offer a good source of calories and protein. Just because eating them seems unusual in the US doesn’t make it wrong.
So, if you like to eat cicadas and have no shellfish allergy or other reason to avoid them, go for it! This may be a very good summer for you.
About the Author
Robert H. Shmerling, MD, Senior Faculty Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing
Dr. Robert H. Shmerling is the former clinical chief of the division of rheumatology at Beth Israel Deaconess Medical Center (BIDMC), and is a current member of the corresponding faculty in medicine at Harvard Medical School. … See Full Bio View all posts by Robert H. Shmerling, MD
A hot weather plan is essential to staying healthy
Here’s a new fact about spring, summer, fall, and sometimes even winter: now that climate change has blurred seasonal boundaries, sizzling heat may be on the way, or currently blanketing your community.
High temperatures stress the body, leading to thousands of heat-related illnesses and deaths every year in the US. Creating a personal heat plan can help you stay safe when the heat index soars.
Caleb Dresser, MD, MPH, is the health care solutions lead for C-CHANGE, the Center for Climate Health and the Global Environment at the Harvard T.H. Chan School of Public Health, and an emergency medicine doctor at Harvard-affiliated Beth Israel Deaconess Medical Center. Below we interview him about who, how, and why heat harms. Then we’ll help you create your personal heat safety plan.
Interview edited for clarity
Who is especially vulnerable during hot weather?
High temperatures can affect anyone. But some people — children, outdoor workers, people who are pregnant or have health problems or disabilities, and older people — are more likely to experience harm when temperatures rise. For example:
- Young children, especially babies, have less physical capacity to deal with very high temperatures.
- People working outdoors may not have access to shade and could be performing physically intensive labor. They need adequate hydration, adequate breaks, and access to a cool space during break time, as OSHA guidelines spell out.
- People with chronic medical conditions, such as kidney disease or heart disease, may have difficulty adapting physiologically to hot weather, or may be more susceptible to its health impacts.
- And some people living with disabilities or certain neurological conditions may have difficulty with thermoregulation — that is, controlling the temperature of their bodies — or may not be able to take actions that keep them safe, such as taking off layers or moving to a cool area.
Which weather patterns create dangerous levels of heat?
Dangerous heat is the result of both high temperatures and high humidity, which interfere with our ability to cool off by sweating. In dry areas, extremely hot temperatures can be dangerous on their own.
Danger zones vary across the United States and around the world. But hospital use and deaths rise once we get above threshold temperatures. The threshold varies in different places depending on whether bodies, cultures, and architecture are adapted to heat.
For example, here in New England, where some people (particularly those of limited means) may not have access to air conditioning, we see increases in healthcare use and deaths at a lower temperature than in the American South, where people and organizations may be more used to dealing with hot weather.
When does hot weather become dangerous to our health?
Risk goes up the longer hot weather sticks around.
One hot day can put some people at risk. A stretch of several hot days in a row during a heat wave is particularly dangerous because it can overwhelm people’s ability to adapt. Eventually people run out of physiological reserves, leading to greater health harms and greater need for medical care.
Surprisingly, spring and early summer are particularly dangerous times because people and organizations aren’t as prepared for hot weather.
How to create your personal heat safety plan
Five key points to help you create a personal heat plan are below. Americares offers further information through heat tip sheets developed with the Harvard C-CHANGE team that are tailored to people in different health circumstances.
Planning is important because intense heat is occurring more often: a Climate Central analysis found 21 additional risky heat days, on average, for 232 out of 249 locations between 1970 and 2022.
- Stay ahead of hot weather. Check apps, websites, TV, or radio for updates on weather today and in coming days. If local weather alerts are available by phone or text, sign up.
- Have a cooling plan. When temperatures soar, you need to spend as much time as possible in cool spaces. Plan options if your home is likely to be too hot and unsafe to stay in. You may be able to stay with a neighbor or family member who has air conditioning until a heat wave passes. Many cities and towns have neighborhood splash pads for children, and open cooling centers or air-conditioned libraries, public buildings, or community centers to everyone — sometimes even overnight. Spending time in air-conditioned businesses or malls, or in a shady green space like a park, may help too.
- Sip plenty of fluids. Water is the best choice. Skip sugary drinks and avoid caffeine or alcohol.
- Use fans correctly. Fans help if surrounding air is relatively cool. If air temperatures are very high, it’s important to dampen your clothes or skin to help keep your body from overheating, and move to a cooler location, if possible.
- Know your personal risks and the signs of heat-related illness. If you have health problems or disabilities, or take certain medicines such as diuretics, talk to your doctor about the best ways for you to cope with heat. It’s also essential to know the signs of heat-related illnesses, which range from heat rash and sunburn to heat cramps, heat exhaustion, and heat stroke. This chart from the Centers for Disease Control and Prevention describes the signs to look for and what you can do, particularly when heat becomes an emergency.
About the Author
Francesca Coltrera, Editor, Harvard Health Blog
Francesca Coltrera is editor of the Harvard Health Blog, and a senior content writer and editor for Harvard Health Publishing. She is an award-winning medical writer and co-author of Living Through Breast Cancer and The Breast … See Full Bio View all posts by Francesca Coltrera
About the Reviewer
Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing
Dr. Howard LeWine is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD