Health Risks of Indoor Exposure to Particulate Matter Workshop Summary (2016) / Chapter Skim
Currently Skimming:
7 Potential Health Concerns
7 Potential Health Concerns
Pages 77-92
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 77... ...
In the first of the day's two sessions, Ryan Allen of Simon Fraser University discussed the effect of indoor PM on cardiovascular health, David Rich from the University of Rochester Medical Center presented emerging evidence linking ambient PM and adverse birth outcomes, and Marc Weisskopf of the Harvard T.H. Chan School of Public Health addressed the role that PM may play in neurological and psychiatric disorders.
|
From page 78... ...
The second mechanism involves the activation of the autonomic nervous system, which in turn affects blood vessels, heart rhythm, heart variability, and other physiological systems. The third mechanism involves direct transport of the smaller particles into the bloodstream, where they interact with blood vessels and various blood cells.
|
From page 79... ...
represents the contribution of respiratory infections; the light blue bar, chronic lung diseases; the medium blue bar, cardiovascular and circulatory diseases; and the dark blue bar (far right) , cancer.
|
From page 80... ...
The data showed that the use of portable HEPA filtration for 7 days, which reduced PM2.5 levels from 11 micro
|
From page 81... ...
Although the data are not entirely consistent, human studies have found links between indoor PM levels and increased systemic inflammation, blood vessel dysfunction, and increased blood pressure. The study of indoor PM, he said, presents an important epidemiologic research challenge, and more research is needed to better characterize the relative toxicity of PM generated indoors and outdoors, of PM from specific indoor and outdoor sources, and of PM2.5 versus UFP.
|
From page 82... ...
. This type of study, using existing datasets of birth outcomes, birth registry data, and pollution levels, has been conducted in numerous locations around the world to evaluate whether air pollution exposure during pregnancy is associated with preterm birth, fetal growth restriction, and pregnancy complications, Rich said.
|
From page 83... ...
. A separate analysis examining a longer study period and more pregnancies than just immediately before, during, and after the Beijing Olympic Games found that increases in 8th-month PM2.5, nitrogen dioxide, sulfur dioxide, and carbon monoxide levels were associated with decreased birth weight, which provided complementary evidence of a late-pregnancy air pollution effect on birth weight.
|
From page 84... ...
Pregnancy cohort studies, longitudinal panel studies that look at biomarkers throughout pregnancy, and intervention studies involving indoor air pollution could be used to study the effects of indoor PM on pregnancy outcomes, he suggested. Such studies would require identifying internal dose markers of individual exposures to indoor pollution and mechanistic biomarkers that could be measured throughout pregnancy.
|
From page 85... ...
The final study Rich discussed was conducted by Ryan Allen and Enkhjargal Gombojav in Ulaanbaatar, Mongolia. It examined whether removing indoor PM using a portable HEPA filtration unit would prevent preterm birth.
|
From page 86... ...
, prompting researchers to look for a possible link between maternal PM exposure during pregnancy and autism. Using data from monitoring networks, meteorological readings, and a set of geographic information system–based predictors, Weisskopf and his colleagues created a time and space model of average predicted PM10 and PM2.5 levels from 1988 to 2007 (Yanosky et al., 2014)
|
From page 87... ...
That may be less of a concern with the aforementioned studies because the extensive work modeling ambient air pollution levels show that the inputs are largely independent of personal behaviors and many other factors that could also be related to disease. However, that independence is not likely to be true for indoor exposures to PM because personal behaviors are an important determinant of exposure.
|
From page 88... ...
He added that he believes that intervention studies, where PM is removed from the indoor environment, could make possible the kind of analysis Kipen would like to see for short-term effects. For larger prospective cohort studies, he suggested doing smaller validation studies to see if there are simple questions that could be asked of study subjects that could probe the link between indoor activities and indoor air particulate levels.
|
From page 89... ...
He added that he is optimistic that collaborations among members of the International Society of Environmental Epidemiology, the International Society of Exposure Science, and the International Society of Indoor Air Quality and Climate would provide a better mechanistic understanding of how to take outdoor PM levels and provide estimates of indoor exposures. Arnold Schwartz from the Milken Institute of Public Health at the George Washington University asked Weisskopf if there were any correlations between pollution and olfactory nerve dysfunction.
|
From page 90... ...
An online workshop participant asked if the neurological health effects of PM exposure are thought to be caused by the irritant effect or by the chemical composition of the particles, and Weisskopf replied that he would guess that the answer is both. The irritant effect could trigger the inflammatory cascade and activation of microglial cells that prune the connections between nerve cells, he said, and if there were metal ions in the particles, such as lead, they could certainly have direct adverse effects on nerve cells.
|
From page 91... ...
by even a few points or having a bad day in the office because of particulate matter, that is a big impact on productivity." He noted, though, that there is the important question of how much exposure people are getting indoors over the course of the entire day. Allen said he agreed completely with Weisskopf, both in terms of potential impact and the importance of determining indoor exposures, and he said that, at least for outdoor exposures, there does not appear to be a threshold in terms of dose–response level.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.