Wildfire smoke has immediate harmful health effects
June 24, 2020
Science Daily/University of British Columbia
Exposure to wildfire smoke affects the body's respiratory and cardiovascular systems almost immediately, according to new research from the University of British Columbia's School of Population and Public Health.
In a study published today in Environmental Health Perspectives, researchers found that exposure to elevated levels of fine particulate matter during wildfire seasons in British Columbia was associated with increased odds of ambulance dispatches related to respiratory and cardiovascular conditions, with increased ambulance dispatches occurring within only one hour after exposure. Among people with diabetes, the researchers found that the odds of health complications increased within 48 hours following exposure to wildfire smoke.
"We have long known about the harmful health effects of wildfire smoke," says Jiayun Angela Yao, the study's lead author who conducted this research while completing her PhD in the UBC School of Population and Public Health. "But it's alarming to see just how quickly fine particular matter seems to affect the respiratory and cardiovascular system. And the acute effects for people with diabetes is relatively new to us."
Particulate matter, also called particle pollution, is made up of tiny pieces of dust, dirt, and smoke in the air. While larger particles can irritate the eyes and throat, fine particles are more dangerous as they can reach deep parts of the lungs and even enter the bloodstream.
For the study, the researchers used statistical modelling to evaluate the relationship between ambulance dispatches, paramedic assessments and hospital admissions related to respiratory, circulatory and diabetic conditions with levels of fine particulate matter during wildfire seasons in B.C. from 2010 to 2015. A total of more than 670,000 ambulance dispatch calls from more than 500,000 individuals were included in the study.
The researchers say this study adds to the limited previous evidence on how quickly exposure to wildfire smoke can have harmful health effects. The findings are especially timely now during the COVID-19 pandemic, as air pollution from wildfire smoke can make viral infections affecting the respiratory and cardiovascular systems even more severe.
With wildfire season quickly approaching in B.C., the researchers say their research underscores the need for rapid public health actions to limit exposure to wildfire smoke.
"It is vital that everyone start preparing for wildfire smoke events to ensure that they are ready, especially since COVID-19 still a serious public health threat in B.C.," says Yao. "Anyone with pre-existing heart and lung disease and diabetes is especially vulnerable and should consider purchasing air cleaners, and ensuring that they have adequate supplies of medication at home."
This study was supported by the Australian Research Council Linkage Program and the British Columbia Lung Association.
https://www.sciencedaily.com/releases/2020/06/200624100045.htm
Air pollution's tiny particles may trigger nonfatal heart attacks
February 14, 2020
Science Daily/Yale School of Public Health
Yale-affiliated scientist finds that even a few hours' exposure to ambient ultrafine particles common in air pollution may potentially trigger a nonfatal heart attack.
Myocardial infarction is a major form of cardiovascular disease worldwide. Ultrafine particles (UFP) are 100 nanometers or smaller in size. In urban areas, automobile emissions are the primary source of UFP.
The study in the journal Environmental Health Perspectives is believed to be the first epidemiological investigation of the effects of UFP exposure and heart attacks using the number of particles and the particle length and surface area concentrations at hourly intervals of exposure.
"This study confirms something that has long been suspected -- air pollution's tiny particles can play a role in serious heart disease. This is particularly true within the first few hours of exposure," said Kai Chen, Ph.D., assistant professor at Yale School of Public Health and the study's first author. "Elevated levels of UFP are a serious public health concern."
UFP constitute a health risk due to their small size, large surface areas per unit of mass, and their ability to penetrate the cells and get into the blood system. "We were the first to demonstrate the effects of UFP on the health of asthmatics in an epidemiological study in the 1990s," said Annette Peters, director of the Institute of Epidemiology at Helmholtz Center Munich and a co-author of this paper. "Since then approximately 200 additional studies have been published. However, epidemiological evidence remains inconsistent and insufficient to infer a causal relationship."
The lack of consistent findings across epidemiological studies may be in part because of the different size ranges and exposure metrics examined to characterize ambient UFP exposure. Chen and his co-authors were interested in whether transient UFP exposure could trigger heart attacks and whether alternative metrics such as particle length and surface area concentrations could improve the investigation of UFP-related health effects.
With colleagues from Helmholtz Center Munich, Augsburg University Hospital and Nördlingen Hospital, Chen examined data from a registry of all nonfatal MI cases in Augsburg, Germany. The study looked at more than 5, 898 nonfatal heart attack patients between 2005 and 2015. The individual heart attacks were compared against air pollution UFP data on the hour of the heart attack and adjusted for a range of additional factors, such as the day of the week, long-term time trend and socioeconomic status.
"This represents an important step toward understanding the appropriate indicator of ultrafine particles exposure in determining the short-term health effects, as the effects of particle length and surface concentrations were stronger than the ones of particle number concentration and remained similar after adjustment for other air pollutants," said Chen. "Our future analyses will examine the combined hourly exposures to both air pollution and extreme temperature. We will also identify vulnerable subpopulations regarding pre-existing diseases and medication intake."
https://www.sciencedaily.com/releases/2020/02/200214134717.htm
Is pollution linked to psychiatric disorders?
August 20, 2019
Science Daily/PLOS
Researchers are increasingly studying the effects of environmental insults on psychiatric and neurological conditions, motivated by emerging evidence from environmental events like the record-breaking smog that choked New Delhi two years ago. The results of a new study publishing August 20 in the open-access journal PLOS Biology by an international group of researchers using large data sets from the US and Denmark suggests a possible link between exposure to environmental pollution and an increase in the prevalence of psychiatric disorders.
The team found that poor air quality was associated with higher rates of bipolar disorder and major depression in both US and Danish populations. The trend appeared even stronger in Denmark, where exposure to polluted air during the first ten years of a person's life also predicted a more than two-fold increase in schizophrenia and personality disorders.
"Our study shows that living in polluted areas, especially early on in life, is predictive of mental disorders in both the United States and Denmark," said computational biologist Atif Khan, the first author of the new study. "The physical environment -- in particular air quality -- warrants more research to better understand how our environment is contributing to neurological and psychiatric disorders."
Although mental illnesses like schizophrenia develop due to a complex interplay of genetic predispositions and life experiences or exposures, genetics alone do not account entirely for variations in mental health and disease. Researchers have long suspected that genetic, neurochemical and environmental factors interact at different levels to affect the onset, severity and progression of these illnesses.
Growing evidence is beginning to provide insight into how components of air pollution can be toxic to the brain: Recent studies on rodents suggest that environmental agents like ambient small particulate matter (fine dust) travel to the brain through the nose and lungs, while animals exposed to pollution have also shown signs of cognitive impairment and depression-like behavioral symptoms. "We hypothesized that pollutants might affect our brains through neuroinflammatory pathways that have also been shown to cause depression-like signs in animal studies," said Andrey Rzhetsky, who led the new study.
To quantify air pollution exposure among individuals in the United States, the University of Chicago team relied on the US Environmental Protection Agency's measurements of 87 air quality measurements. For individuals in Denmark, they used a national pollution register that tracked a smaller number of pollutants with much higher spatial resolution.
The researchers then examined two population data sets, the first being a U.S. health insurance claims database that included 11 years of claims for 151 million individuals. The second dataset consisted of all 1.4 million individuals born in Denmark from 1979 through 2002 who were alive and residing in Denmark at their tenth birthday. Because Danes are assigned unique identification numbers that can link information from various national registries, the researchers were able to estimate exposure to air pollution at the individual level during the first ten years of their life. In the US study, exposure measurements were limited to the county level. "We strived to provide validation of association results in independent large datasets," said Rzhetsky.
The findings have not been without controversy. "This study on psychiatric disorders is counterintuitive and generated considerable resistance from reviewers," said Rzhetsky. Indeed, the divided opinions of the expert reviewers prompted PLOS Biology to commission a special companion article from Prof. John Ioannidis of Stanford University (Ioannidis is unconnected with the study, but assisted the journal with the editorial process).
"A causal association of air pollution with mental diseases is an intriguing possibility. Despite analyses involving large datasets, the available evidence has substantial shortcomings and a long series of potential biases may invalidate the observed associations," says Ioannidis in his commentary. "More analyses by multiple investigators, including contrarians, are necessary."
Rzhetsky also cautioned that the significant associations between air pollution and psychiatric disorders discovered in the study do not necessarily mean causation, and said that further research is needed to assess whether any neuroinflammatory impacts of air pollution share common pathways with other stress-induced conditions.
https://www.sciencedaily.com/releases/2019/08/190820141604.htm
Air pollution linked to childhood anxiety
Researchers investigate traffic-related air pollution and symptoms of childhood anxiety, through neuroimaging
May 21, 2019
Science Daily/University of Cincinnati Academic Health Center
A new study looks at the correlation between exposure to traffic-related air pollution (TRAP) and childhood anxiety, by looking at the altered neurochemistry in pre-adolescents.
Exposure to air pollution is a well-established global health problem associated with complications for people with asthma and respiratory disease, as well as heart conditions and an increased risk of stroke, and according to the World Health Organization, is responsible for millions of deaths annually. Emerging evidence now suggests that air pollution may also impact the metabolic and neurological development of children.
A new study from researchers at the University of Cincinnati and Cincinnati Children's Hospital Medical Center looks at the correlation between exposure to traffic-related air pollution (TRAP) and childhood anxiety, by looking at the altered neurochemistry in pre-adolescents.
"Recent evidence suggests the central nervous system is particularly vulnerable to air pollution, suggesting a role in the etiology of mental disorders, like anxiety or depression," says Kelly Brunst, PhD, assistant professor in the Department of Environmental Health at the College of Medicine, and lead author on the study.
"This is the first study to use neuroimaging to evaluate TRAP exposure, metabolite dysregulation in the brain and generalized anxiety symptoms among otherwise healthy children," says Brunst.
The study was published by the journal Environmental Research.
The researchers evaluated imaging of 145 children at an average age of 12 years, looking specifically at the levels of myo-inositol found in the brain through a specialized MRI technique, magnetic resonance spectroscopy. Myo-inositol is a naturally-occurring metabolite mainly found in specialized brain cells known as glial cells, that assists with maintaining cell volume and fluid balance in the brain, and serves as a regulator for hormones and insulin in the body. Increases in myo-inositol levels correlate with an increased population of glial cells, which often occurs in states of inflammation.
They found that, among those exposed to higher levels of recent TRAP, there were significant increases of myo-inositol in the brain, compared to those with lower TRAP exposure. They also observed increases in myo-inositol to be associated with more generalized anxiety symptoms. "In the higher, recent exposure group, we saw a 12% increase in anxiety symptoms," says Brunst.
Brunst noted however, that the observed increase in reported generalized anxiety symptoms in this cohort of typically developing children was relatively small and are not likely to result in a clinical diagnosis of an anxiety disorder. "However, I think it can speak to a bigger impact on population health ... that increased exposure to air pollution can trigger the brain's inflammatory response, as evident by the increases we saw in myo-inositol," says Brunst. "This may indicate that certain populations are at an increased risk for poorer anxiety outcomes."
https://www.sciencedaily.com/releases/2019/05/190521162421.htm