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Measuring Carbon Content in Airway Macrophages Exposed to Carbon-Containing Particulate Matters
Published on: July 12, 2024
Ultrafine, fine, and black carbon particle concentrations in California child-care facilities
F W Gaspar1, R Maddalena2, J Williams3
1Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA.
Insights
Child care centers have significant airborne particulate matter (PM) exposures, including ultrafine particles (UFP) and black carbon. These exposures are linked to traffic and poor air exchange, highlighting risks for children's respiratory health.
Area of Science:
- Environmental Health
- Air Quality Monitoring
- Pediatric Respiratory Health
Background:
- Children in child care settings experience unknown exposures to airborne particulate matter (PM).
- PM is linked to asthma and respiratory illnesses, a major concern for young children's health.
- Data gaps exist regarding indoor PM levels and their determinants in child care environments.
Purpose of the Study:
- To measure airborne particulate matter (PM) concentrations, including ultrafine particles (UFP), PM2.5, PM10, and black carbon, in child care facilities.
- To examine associations between indoor PM levels and potential determinants like air exchange rates and traffic volume.
- To evaluate the utility of a low-cost optical particle measuring device (Dylos monitor) for indoor PM monitoring.
Main Methods:
- Conducted air quality monitoring in 40 California child-care facilities.
- Measured indoor concentrations of UFP, PM2.5, PM10, and black carbon using established methods.
- Collected data on potential determinants such as air exchange rate and proximity to traffic.
Main Results:
- Median indoor concentrations were 14,000 particles/cm³ for UFP, 15 μg/m³ for PM2.5, 48 μg/m³ for PM10, and 0.43 ng/m³ for black carbon.
- Indoor black carbon was inversely associated with air exchange rate and positively associated with nearby traffic volume.
- The Dylos monitor showed potential as a low-cost tool for indoor PM monitoring.
Conclusions:
- Child care facilities exhibit significant indoor particulate matter exposures.
- Traffic-related air pollution and inadequate ventilation are key contributors to elevated PM levels.
- Further research is needed on health impacts and mitigation strategies for PM in child care settings.
Abstract:
Although many U.S. children spend time in child care, little information exists on exposures to airborne particulate matter (PM) in this environment, even though PM may be associated with asthma and other respiratory illness, which is a key concern for young children. To address this data gap, we measured ultrafine particles (UFP), PM2.5 , PM10 , and black carbon in 40 California child-care facilities and examined associations with potential determinants. We also tested a low-cost optical particle measuring device (Dylos monitor). Median (interquartile range) concentrations for indoor UFP, gravimetric PM2.5 , real-time PM2.5 , gravimetric PM10 , and black carbon over the course of a child-care day were 14 000 (11 000-29 000) particles/cm3 , 15 (9.6-21) μg/m3 , 15 (11-23) μg/m3 , 48 (33-73) μg/m3 , and 0.43 (0.25-0.65) ng/m3 , respectively. Indoor black carbon concentrations were inversely associated with air exchange rate (Spearman's rho = -.36) and positively associated with the sum of all Gaussian-adjusted traffic volume within a one-kilometer radius (Spearman's rho = .45) (P-values <.05). Finally, the Dylos may be a valid low-cost alternative to monitor PM levels indoors in future studies. Overall, results indicate the need for additional studies examining particle levels, potential health risks, and mitigation strategies in child-care facilities.
