Smoke from more than 200 wildfires burning across Canada has been turning skies hazy in North American cities far from the flames. We asked Chris Migliaccio, a toxicologist at the University of Montana who studies the impact of wildfire smoke on human health, about the health risks people can face when smoke blows in from distant wildfires.

What’s in wildfire smoke that’s a problem?

When we talk about air quality, we often talk about PM2.5. That’s particulate matter 2.5 microns or smaller – small enough that it can travel deep into the lungs.

Exposure to PM2.5 from smoke or other air pollution, such as vehicle emissions, can exacerbate health conditions like asthma and reduce lung function in ways that can worsen existing respiratory problems and even heart disease.

But the term PM2.5 only tells you about size, not composition – what is burning can make a significant difference in the chemistry.

In the northern Rockies, where I live, most fires are fueled by vegetation, but not all vegetation is the same. If the fire is in the wildland urban interface, manufactured fuels from homes and vehicles may also be burning, and that’s going to create its own toxic chemistry, as well. Chemists often talk about volatile organic compounds, (VOCs), carbon monoxide and PAHs, or polycyclic aromatic hydrocarbons produced when biomass and other matter burns having the potential to harm human health.

How does inhaling wildfire smoke harm human health?

If you have ever been around a campfire and got a blast of smoke in your face, you probably had some irritation. With exposure to wildfire smoke, you might get some irritation in the nose and throat and maybe some inflammation. If you’re healthy, your body for the most part will be able to handle it.

As with a lot of things, the dose makes the poison – almost anything can be harmful at a certain dose.

Generally, cells in the lungs called alveolar macrophages will pick up the particulates and clear them out – at reasonable doses. It’s when the system gets overwhelmed that you can have a problem.

One concern is that smoke can suppress macrophage function, altering it enough that you become more susceptible to respiratory infection. A colleague who looked at lag time in the effect of wildfire smoke exposure found an increase in influenza cases after a bad fire season. Studies in developing countries have also found increases in respiratory infections with people who are cooking on open fires in homes.

The stress of an inflammatory response can also exacerbate existing health problems. Being exposed to wood smoke won’t independently cause someone to have a heart attack, but if they have underlying risk factors, such as significant plaque buildup, the added stress can increase the risk.

Researchers are also studying potential effects on the brain and nervous system from inhaled particulate matter.

When smoke blows over long distances, does its toxicity change?

We know that the chemistry of wildfire smoke changes. The longer it’s in the atmosphere, the more the chemistry will be altered by ultraviolet light, but we still have a lot to learn.

Researchers have found that there seems to be a higher level of oxidation, so oxidants and free radicals are being generated the longer smoke is in the air. The specific health effects aren’t yet clear, but there’s some indication that more exposure leads to greater health effects.

The supposition is that more free radicals are generated the longer smoke is exposed to UV light, so there’s a greater potential for health harm. A lot of that, again, comes down to dose.

Chances are, if you’re a healthy individual, going for a bike ride or a hike in light haze won’t be a big deal, and your body will be able to recover.

If you’re doing that every day for a month in wildfire smoke, however, that raises more concerns. I’ve worked on studies with residents at Seeley Lake in Montana who were exposed to hazardous levels of PM2.5 from wildfire smoke for 49 days in 2017. We found a decrease in lung function a year later. No one was on oxygen, but there was a significant drop.

This is a relatively new area of research, and there’s still a lot we’re learning, especially with the increase in wildfire activity as the planet warms.

What precautions can people take to reduce their risk from wildfire smoke?

If there is smoke in the air, you want to decrease your exposure.

Can you completely avoid the smoke? Not unless you’re in a hermetically sealed home. The PM levels aren’t much different indoors and out unless you have a really good HVAC system, such as those with MERV 15 or better filters. But going inside decreases your activity, so your breathing rate is slower and the amount of smoke you’re inhaling is likely lower.

We also tend to advise people that if you’re in a susceptible group, such as those with asthma, create a safe space at home and in the office with a high-level stand-alone air filtration system to create a space with cleaner air.

Some masks can help. It doesn’t hurt to have a high-quality N95 mask. Just wearing a cloth mask won’t do much, though.

Most states have air quality monitors that can give you a sense of how bad the air quality is, so check those sites and act accordingly.

This article was updated May 22, 2023, with the morning’s updated wildfire smoke map.

Christopher T. Migliaccio, Research Associate Professor in Toxicology, University of Montana

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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How can I make studying a daily habit? – Jesni P., age 15, Mumbai, Maharashtra, India

Studying – you know you need to do it, but you just can’t seem to make it a habit. Maybe you forget, become distracted or just don’t want to do it.

Understanding what a habit is, and how it forms, can help you figure out how to study on a daily basis.

The habit loop

A habit is a behavior you do regularly or routinely. As a professor who studies how to help students become better readers and writers, I can tell you that research shows habits have a loop: cue, routine, reward.

Let’s say you have a habit of eating a snack after school. When school is about to end, you start to feel hungry. Dismissal is the cue to get your snack.

Eating the snack is the routine. The reward is that it tastes good and your hunger goes away, which reinforces the habit – and makes you want to repeat the loop again the next day.

Here are the things you need to make a studying loop:

1. A set time to study every day.
2. A cue to start studying.
3. An environment that helps you stick to your studying routine.
4. A reward for studying.

Setting a time

When you do things at the same time every day, it is easier to remember to do them.

To determine how much time you should set aside each day to study, multiply your grade level by 10 minutes.

That means if you’re in third grade, you would plan to spend about 30 minutes per day studying. This can include the time you spend practicing your reading. If you’re in eighth grade, you would spend 80 minutes per day – that is, one hour and 20 minutes – studying.

Research suggests that two hours is the maximum amount of daily studying time that is beneficial. Spending more time than that on a regular basis can cause stress, anxiety and possibly disturb healthy sleep habits.

So choose a single block of time during the afternoon or evening when you will have the right amount of time to study every day.

There may be days when your assignments do not fill the full block of time that you have set. On those days, you should spend time reviewing material that you’ve already studied; regularly going back over information helps you remember it and think about how to integrate it with the new things you’re learning.

You also can spend those extra minutes reading a book. Studies show a daily habit of reading for 20 minutes will improve your vocabulary, language skills and overall knowledge.

The cue

Studying at the same time every day is one cue, but you may need something more concrete when first forming your habit.

This can be a calendar reminder you set on your phone or laptop, or something as simple as a card with the word “study” printed on the front. You can leave the card where you hang up your coat or put down your bag when you get home from school – or on your television or computer screen.

On the back of the card, write the word “studying.” Then keep this side facing up and posted to the back of your computer, on your door, or above your desk while you work.

This will signal to others that they should not disturb you during this time. When you finish studying, return the card to its starting spot so that it’s ready to remind you to study the next day.

Your study environment

To help yourself study, you need a place set up for work and not for doing other things. Do not study on your bed – that’s for sleeping – or in front of the television, or anywhere it’s difficult to hold and use the materials you need. Best option: a table or desk with good lighting.

Your study place should limit distractions. That includes other people’s conversations and all media: TV, video games, social media, texts or music. Research repeatedly has shown the human brain cannot multitask well; people make more mistakes if they try to do two things at the same time, especially when one of those things requires concentration. Bouncing back and forth between two things also means it takes longer to complete the task.

Although you should put away electronic devices when studying, that may not be an option if you need them for homework. If that’s the case, set the “do not disturb” notification on your phone, silence incoming notifications and close all social media and gaming apps.

Gaming, social media and video apps are programmed to make you want to keep checking or playing them. That means you have to replace the bad habit of constantly using them with the good habit of studying for a designated block of time.

The reward

That said, after you finish studying, you can give yourself a little gaming or social media time as your reward.

With time, the studying itself will become its own reward. Improving your knowledge and skills will give you a sense of achievement and make you more confident and happier at school. But while forming your study habit, a really fun reward will help you stick with it.

This is especially true if the subject you’re studying is difficult for you. No one likes to do something they think they’re not very good at. However, it’s impossible to get better if you do not practice, and studying is just like practicing a sport, instrument or hobby.

How long it takes

The amount of time it takes to make studying a daily habit can be anywhere from 21 days to a few months, depending upon the person.

To help you stay with it, find a study buddy to form the habit along with you. Ask your family not to interrupt you during study time. And consider using apps to set goals and track your study time so you can watch your habit form and celebrate your progress. The good news: Daily studying gets easier the more you do it.

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Deborah Reed, Professor of Education, University of Tennessee

This article is republished from The Conversation under a Creative Commons license. Read the original article.