Wildfire Particulates in Smoke Dangerous to Brain Function

"Some particles from wildfire smoke have been shown to be able to cross the blood-brain barrier and cause inflammation of the brain."

Kent Pinkerton, pediatrics professor, University of California, Davis

 

"Hitchhiking on these tiny particulate matter are pieces that are toxic metals -- lead from leaded gasoline, iron from brake pads and platinum from catalytic converters."

"It may be that this particulate matter entering into our nose and the gateway to our brain, which is normally protected by a blood-brain barrier, is getting exploited by the front door." 

"Whether you are a newborn baby or an older adult with Alzheimer's disease, air pollution is likely harmful to your brain."

Ray Dorsey, neurology professor, University of Rochester, New York 

"Studying cognitive abilities is important because they are core to all daily life functioning and can be key to understanding individual needs as they rebuild and rehabilitate in disaster-affected communities."

January study, journal PLOS Climate

A person travels in a boat past people walking on the boardwalk as smoke from the McDougall Creek wildfire blankets the area on Okanagan Lake, in Kelowna, B.C., Friday, Aug. 18, 2023. (THE CANADIAN PRESS/Darryl Dyck)

Pollution from wildfire smoke -- according to a growing body of international research -- can produce cognitive deficits, post-traumatic stress and may increase the risk of dementia, Alzheimer's and Parkinson's disease. The effects of wildfires have conventionally and to the present, been studied on lungs, hearts and blood of affected patients. Researchers, however have begun studying how fine particulate matter from wildfire smoke can enter the body and travel to the brain.

According to Professor Pinkerton the nose acts as a filter to ensure some inhaled particles don't reach the lungs. During wildfires, though, concern has arisen that tiny soot particles and other chemicals in smoke have the capacity to enter body cells and nose nerves. Scientists know that these entries can have a direct brain connection. Cells and nerves can get inflamed and damaged by wildfire smoke, as they pass from nose to brain.

Wildfires in Canada's Northwest Territories and British Columbia saw thousands of people forced to vacate their homes, in one of the worst years for wildfires in the country, where close to 137,000 square kilometres of land have been scorched. The composition of wildfire smoke is not restricted to vegetation from trees and other plants, but includes as well products caught in the flames which would include metals from vehicles and homes, plastic and fabric fibers.

Some such particulate matter from wildfire smoke is sufficiently minuscule that it can travel into the smell centres of the brain, emphasized neurology professor Ray Dorsey. Higher concentrations of heavy metal are seen in the brains of people with Parkinson's and Alzheimer's. Smell centres of the brain damage is found almost universally in patients with these two diseases, Dr. Dorsey explains.

A July 2018 study published in the journal Environmental Research saw a group of international researchers find that people in Mexico City exposed to air pollution showed the signatures of Alzheimer's and Parkinson's in their brains. "Exposure to air pollutants plays a major role in the development and-or acceleration of Alzheimer's disease" the study, called Hallmarks of Alzheimer's Disease Are Evolving Relentlessly in Metropolitan Mexico City Infants, Children and Young Adults concluded.

Recent reports suggest that air pollution from wildfires presents a denser or higher concentration of particulate matter than does air pollution from vehicular traffic. A January study published in the journal PLOS Climate found people exposed to smoke from the 2018 Camp fire, the most destructive wildfire in the history of California, had "significantly" greater chronic symptoms of post-traumatic stress disorder, anxiety and depression than those not exposed to the fire.

 

A decrease in cognitive performance -- the ability to suppress distractions and focus on a task at hand -- results from exposure to wildfires, concluded lead author of the California Fire study, Jyoti Mishra. Six months following the wildfire the study was initiated, when the smoke had subsided. Thsre's a "lot of complex interactions" when a person suffers from loss of property, family and injury, explains Dr. Mishra. 

 

Emotional responses generally associated with post-traumatic stress disorder can be set off by wildfires.

 The body reacts to particulate matter from wildfire smoke, in the same way it would with inflammation. Particulates as well could enter the lungs and chronically affect the brain, at the height of the wildfires. 

Smoke from wildfire rises into pyrocumulus cloud. PATRICK T. FALLON/AFP via Getty Images

"We don't know that exact link as to how the particulates can affect the brain systems over the long term, but what we found in a series of studies was that there was definitely prevalence of climate trauma."

"We see the final outcome, we see that there's cognitive deficits, there are brain changes, there are psychiatric symptoms, but how do you get from wildfire smoke to that kind of an end point?"

"Those intermediate complexities ... are not well understood."

Jyoti Mishra, lead author, California fire study, associate professor of psychiatry, University of California, San Diego

Knock-Knock : Who's There?

"Concussions happen all the time. You get tackled and your head hits the turf, you see flashes of light or ringing in your ears but you're able to play -- that's a concussion."

"That's what's kind of frightening about the concussion thing. It's the ones that seem minor that do the damage, because you're able to keep going, and still today, there's probably guys that have them, they're 'I'm not going out'."

"I don't remember my daughter playing soccer, playing youth soccer, one summer. I don't remember that. I got a pretty good memory and I have a tendency like we all do to say, 'Where are my glasses?' and they're on your head. This was pretty shocking to me that I couldn't remember my daughter playing youth soccer, just one summer, I think."

"I remember her playing basketball, I remember her playing volleyball, so I kind of think maybe she only played a game or two. I think she played eight. So that's a little bit scary to me."

Brett Favre, professional footballer, NFL, Hall of Famer

Getty Images

 

Favre is on record as having stated his opinion that youth tackle football should be banned until players at least reach age 14. He has taken part in Concussion Legacy Foundation events. He hasn't encouraged his three grandsons to play football, considering it "too risky" to play the sport with no effective treatment for head trauma.

 

If anyone should know, he should. He has experienced enough of them over the years. And he is beyond fortunate that the after-effects are as relatively mild as he states them to be. For others that isn't the case.

During the years of his NFL career Brett Favre was notorious for the number of hard hits he took. He's looking back now and reconsidering his time on the field. In an interview he recalled suffering frequent head injuries; by his estimation the number of concussions he suffered would exceed 50 per season during his 20-year career. "So, based on that, thousands", he emphasized.

His career spanned 1991 to 2010, the third-most sacked player in NFL history with a total of 525 instances. Known for his ability to play through injuries, he started for a record 297 consecutive regular-season games -- or 321 counting playoff games. Following his retirement three years ago, he detailed the end effect repeated concussions have had on him.

"The thing about concussions is we still don't know a lot about them. If you had asked me this 10 years ago, how many concussions I had, I would have said three."

"The reason I would have said three [is] I thought concussions were where you get knocked out, where you black out, for a period of time you don't know where you are, memory loss, dizzy."

"A boxer gets knocked out and tries to get up, his legs are rubber. That's a concussion." 

"Having kids play before high school is just not worth the risk. CTE is a terrible disease, and we need to do everything we can to prevent it for the next generation of football players."

Brett Favre 

 

The Centers for Disease Control defines concussions as traumatic injuries caused by hits to the head or body, causing the brain to move around the skull. Like boxers, football players potentially and actually experience multiple concussion-causing blows throughout their professional careers. Chronic traumatic encephalopathy (CTE) can result from repeated concussions. CTE is characterized by long-term effects like concentration difficulties, memory retention problems, and a state of depression.

 

Now 52, a bit of introspection since his retirement has led Favre to the realization that while he was actively playing football he misunderstood what the constant knocks to his skull represented. They were more than hard knocks, they were concussions. He felt confident before mulling over the situation after he found out what the symptoms of those hard skull knocks really represent that he was wrong the entire time with the realization that he was experiencing a dangerous situation, one that has left him with the impression there was a vacuum in parts of his lived memory.

Former quarterback Brett Favre. Photo: Mike Ehrmann/Getty

Vulnerability of the Human Brain

"Instead of looking just at how the head is moving, we can visualize what's happening to a representative brain model inside the head."
"It's next-level information that can be used to validate the computer models used in helmet design."
"We're trying to understand the specific injuries that the cells undergo when the brain stretches. We want to know how the stretch and pull response of the brain might lead to injury and, specifically, where those injuries might be occurring." 
"We want to understand the critical limits of what those cells and those structures can take before they're affected."
"The brain is a very complex system and understanding exactly what leads to injury is not a trivial matter. We're still developing that understanding."
"The ultimate goal of this research is to change the way helmets are designed to improve helmet response, and also to influence in the longer term how helmets are evaluated and the safety standards applied to them."
Oren Petel, researcher, mechanical and aerospace engineering, Carleton University, Ottawa

Folds in a human brain. David Duprey / AP

"In hockey, you don’t see people dying from a hit to the head, and that is because the helmet works reasonably well for catastrophic injury."
“Football, you do get some deaths, but it’s fairly well-managed or mitigated. But neurological disease and concussion are not managed very well by a helmet. So this data will be very helpful for us; it will get us precision. The better data we get to capture the risk of concussion, the more innovation we can do in terms of helmets to reduce that risk."
“So, when we look at trauma related to neurological disease, we are only validating part of the brain and its response to trauma. This study is going to give us a really good opportunity to map different parts of the brain. . . . We are going to be able to get into parts of the brain we think are really important in terms of predicting risk."
"The brain is mostly water, so it doesn’t compress, but it does shear. It’s like jello. You can’t compress jello easily but you can shear it. And when you shear it, you damage it, and that is what is happening in the brain."
"We’re trying to understand trauma associated with sport that put athletes at risk for neurological disease. We connect the trauma to disease."
Dr. Blaine Hoshizaki, director, Neurotrauma Impact Science Laboratory, University of Ottawa

Although research into concussion has advanced in the last ten years more is required to understand what happens in the brain when a high-speed collision occurs. The design of a helmet to increase protection against injury is a high priority. Professor Petal aspires for the research he is engaged with to ultimately ensure greater safety for athletes in sports competitions such as hockey and football. From his position at Carleton University, Professor Petal applied for funding to develop a design he came up with, an X-ray system, and an impact research laboratory.

He found that funding with the Canada Foundation for Innovation and the Ontario Research Fund which came up with the required funding, and at a cost of about $320,000, both the lab and the X-ray system were completed in the space of two years. Ongoing research of Professor Petel's lab has brought contributions to his work from the Canadian Institutes of Health Research and the Natural Sciences and Engineering Research Council.

The completed laboratory is lined with lead to enable his very special type of research, equipped with a linear impactor, capable of delivering a head blow at 12 metres per second. An X-ray system capable of capturing images of the collision at 100,000 frames per second complete the major constituents of this very specialized research lab where Professor Petel and his research team are able to recreate what occurs with a helmet -- and the brain it protects -- during a high-speed collision.



The high-resolution images produced by the X-ray system lend themselves to the creation of a video -- known as cineradiography -- that illustrates interaction between a helmet and a head while at the same time revealing the physical response of the brain to an impact; the manner in which the brain compresses, twists and stretches. This revealing process and the information it contains will lead researchers in their work of designing improved helmets for hockey and football players, soldiers and cyclists.

In partnership with Defence Research and Development Canada, one project is to test what occurs to a synthetic brain within a plastic head model where markers are implanted inside the artificial brain for the purpose of measuring how it deforms in a collision. Yet another project in collaboration with Carleton neuroscience professor Matt Holahan is how pig brains [taken from an abattoir] respond to an impact. Validation of computer models commonly in use in head-injury research, another project.

When Dr. Petel studied at McGill University, he immersed himself in blast research when he joined the Shockwave Physics Group there. "It just sounded like a lot of fun, things impacting each other. And it was really challenging. Your experiments typically last several microseconds, several millionths of a second, and you have to collect all your data in the time before your experiment is destroyed", he explained.

He studied the response of ballistic armour and allied protective materials to an explosion, becoming ever more interested in the dynamics of blast injuries of what was occurring internally when a body was hit by a shock wave. And what made the lungs and brain so susceptible to injury, along with the question of how the tissue was becoming deformed. Which led the researcher to the conclusion that answers to those questions could improve protective equipment design.

As he initiated his study into injury biomechanics, at a conference years ago he questioned an experienced researcher why it was that more information relating to the reaction of internal tissue to a blast wasn't available. The response was there was no known way to measure what was happening at such high speeds. "So why isn't someone developing something to measure this?", he asked. "If you think you're so smart, why don't you do it?" was the comeback. So he set about to do just that.

Here, he sets up a machine that hits the “head” with great velocity from which he can measure impact and damage to the head. Julie Oliver / Postmedia

Memory Restoration

"We all have good days and bad days, times when we're foggy or when we're sharp."
"We found that jostling the system when it's in a low-functioning state can jump it to a high-functioning one."
"We find there's even more variability during retrieval than encoding more potential to increase performance." 

"It’s one thing to go back through your data, and find that the stimulation works. It’s another to have the program run on its own and watch it work in real time."

"Now that the technology is out of the box, all sorts of neuro-modulation algorithms could be used in this way."Michael Kahana, psychology professor, University of Pennsylvania

"We have good evidence that things like nicotine and aerobic exercise improve some aspects of attention."
"The stimulation may be activating some of the same systems, only more directly and precisely."
Zach Hambrick, professor of psychology, Michigan State University

"One woman in her sixties got to where she could recall more than one hundred words in correct order."
"That ability didn't transfer to any improvement in general cognition, like the ability to concentrate, to store new information without using the technique, or speed of processing."
David Balota, researcher, Washington University, Missouri

A magnetic resonance image of an epileptic brain. Scientists have tested a brain implant on people with epilepsy that aided memory. Credit Bsip/UIG, via Getty Images

It was revealed in February in the journal Nature Communications that scientists had developed a brain implant whose purpose is to boost memory. Yet another piece of bioscience coupled with advanced technology to aid people suffering from serious memory loss. Scientists at the University of Pennsylvania and Thomas Jefferson University studied decades of work devoted to the decoding of brain signals with the use of the most advanced techniques of machine learning.

The result was the development of a new implant represented by an array of electrodes embedded deep in the brain to monitor electrical activity -- somewhat like a peacemaker in that it can deliver a stimulating pulse when required and that would be when the brain struggles to store new information. It is felt that this device may provide support to people with extreme thought deficits and in so doing radically improve their lives.

For others, with normal brain function and thought processes, the central discovery advancing the device; that a wandering brain can be boosted to make it more alert -- already has resonance for people have been stimulating their brains and minds on their own, somewhat less formally and invasive in the technical-engineering sense, by using caffeine, nicotine, prescription drugs, and when all else fails, a brisk run in fresh air around green trees, to clear the mind and boost brainpower.

Some individuals have remarkable memories capable of storing data and retrieving it at will. Those who score high in memory tests depend on cues specific to their memory capabilities, thought to be partially inherited -- though psychologists appear to believe that almost anyone is capable of expanding a native ability, using techniques to mentally arrange new names, facts or words linked to a familiar place.

Science Alert

Researchers at Washington University in Missouri conducted a study where fifty older adults were trained to memorize word lists, with the use of location imagery. Building on the capacity to recall lists of facts using either imagery-based training or with the use of a brain implant may appear to those with normal memories to be without value; on the other hand, those suffering from serious deficits may find enormous value in the new brain implant technology.

According to the researchers involved in discussions on commercializing the technology, the device could correct injuries by aiding in listing and recalling critical life-enhancing details. As, for example, whom to contact for aid, how to use the telephone, keeping everyday but vital information foremost in mind. Perhaps the simple expedient of making reminder notes clear and concise and in handy view hadn't occurred as a simpler, more practical nudge in aiding memory...??

On the other hand, scientists looking to the future are perhaps likelier to switch the technology to the efficiency and practicality of memory retrieval, instead of mere memory storage.

Brain activity    SCIEPRO / Getty Images

Violent-Impact-Driven Long-Term Brain Disease

"We're really excited about this. No one else in the world will have these data sets."
"In hockey, you don't see people dying from a hit to the head, and that is because the helmet works reasonably well for catastrophic injury. Football, you do get some deaths, but it's fairly well-managed or mitigated. But neurological disease and concussion are not managed very well by a helmet. So this data will be very helpful for us; it will get us precision."
"The better data we get to capture the risk of concussion, the more innovation we can do in terms of helmets to reduce that risk."
"So, when we look at trauma related to neurological disease, we are only validating part of the brain and its response to trauma. This study is going to give us a really good opportunity to map different parts of the brain. ... We are going to be able to get into parts of the brain we think are really important in terms of predicting risk."
"The brain is mostly water, so it doesn't compress, but it does shear. It's like Jell-O. You can't compress Jell-O easily but you can shear it. And when you shear it,  you damage it, and that is what is happening in the brain."
"We're trying to understand trauma associated with sport that put athletes at risk for neurological disease. We connect the trauma to disease."
Dr. Blaine Hoshizaki, director, Neurotrauma Impact Science Laboratory, University of Ottawa

David Koncan, a Phd candidate in the Neurotrauma Impact Science lab at the University of Ottawa, measures impact on a head with a linear impactor machine. Julie Oliver / Postmedia

"When you think about environmental exposure to a chemical, you have acute exposure and low-level, long-term, repeated exposure that can be detrimental in the long run."
"If you're looking at head injuries in sport, you have acute, severe injuries but also low-level repeated injury that over time could develop into a disabling condition."
Dr. Oren Petel, department of mechanical and aerospace engineering, Carleton University

Thee has been a long-overdue increase in focus on long-term brain disease, following on the findings of a study by Boston University scientists. Their research pointed out that close to 90 percent of 202 studied brains -- donated by individuals or families resulting from behavioural issues or brain disease while the individuals were alive -- of deceased football players, revealed that signs of chronic traumatic encephalopathy were present in forms of mild to severe.

Similar research undertaken on the brains of former NFL players as part of the sample, proved even higher for the presence of chronic traumatic encephalopathy (CTE), at 99 percent. It yet remains an educated hypothesis that there is a definite but undiscovered tell-tale link between concussions and CTE. Neurological scientists undertaking their unprecedented search in this area do so with the drawback of the reality that parts of the human brain have not yet been entirely mapped.

The Ottawa study now being undertaken through cutting-edge research into brain injuries and sport helmet design will have the function of ultimately succeeding in filling in some of those unexplored areas of the brain. Together with Dr. Patrick Bishop, lead researcher from University of Waterloo with a background in sports-injury prevention and head protection, Dr. Hoshizaki and Dr. Petel are collaborating in the use of high-speed X-rays to reach their eventual goal.

A research grant to the value of $700,000 was received for this express purpose; a three-year study on the scientific response within the unknown reaches of the brain, reacting to high-speed impacts. Cadavers will be utilized in impact-testing labs, along with computer mapping in the end game of designing a safer helmet for sports such as football and hockey. As yet unknown is whether repetitive, lower-impact strikes can result in long-term injuries to the brain, or whether it is just one violent slam causing concussion that is responsible.

The intention is that the researchers will discover the way in which the brain moves, becomes deformed and tends to shear under the pressure of violent contact. Relatively minor-seeming and localized effects might turn out to be worthwhile investigating as well, to determine just how the complex interaction of the brain is involved with violent contact to the skull.

As far as Dr. Hoshizaki's lab is concerned, it is an imperative that they succeed in developing a helmet capable of reducing brain rotation on violent contact. "It makes no sense to decrease participation in sport and recreation", he states, "because it enriches people's lives."