A Preliminary Assessment of the Role of Ambient Nitric Oxide Exposure in Hospitalization with Respiratory Syncytial Virus Bronchiolitis

Short-Term Elevation of Fine Particulate Matter Air Pollution and Acute Lower Respiratory Infection

RATIONALE

Nearly 60% of U.S. children live in counties with particulate matter less than or equal to 2.5 μm in aerodynamic diameter (PM_2.5) concentrations above air quality standards. Understanding the relationship between ambient air pollution exposure and health outcomes informs actions to reduce exposure and disease risk.

OBJECTIVES

To evaluate the association between ambient PM_2.5 levels and healthcare encounters for acute lower respiratory infection (ALRI).

METHODS

Using an observational case-crossover design, subjects (n = 146,397) were studied if they had an ALRI diagnosis and resided on Utah's Wasatch Front. PM_2.5 air pollution concentrations were measured using community-based air quality monitors between 1999 and 2016. Odds ratios for ALRI healthcare encounters were calculated after stratification by ages 0-2, 3-17, and 18 or more years.

MEASUREMENTS AND MAIN RESULTS

Approximately 77% (n = 112,467) of subjects were 0-2 years of age. The odds of ALRI encounter for these young children increased within 1 week of elevated PM_2.5 and peaked after 3 weeks with a cumulative 28-day odds ratio of 1.15 per +10 μg/m³ (95% confidence interval, 1.12-1.19). ALRI encounters with diagnosed and laboratory-confirmed respiratory syncytial virus and influenza increased following elevated ambient PM_2.5 levels. Similar elevated odds for ALRI were also observed for older children, although the number of events and precision of estimates were much lower.

CONCLUSIONS

In this large sample of urban/suburban patients, short-term exposure to elevated PM_2.5 air pollution was associated with greater healthcare use for ALRI in young children, older children, and adults. Further exploration is needed of causal interactions between PM_2.5 and ALRI.

Children's Exposure to Environmental Contaminants: An Editorial Reflection of Articles in the IJERPH Special Issue Entitled, "Children's Exposure to Environmental Contaminants"

Children are at increased vulnerability to many environmental contaminants compared to adults due to their unique behavior patterns, increased contaminant intake per body weight, and developing biological systems. Depending upon their age, young children may crawl on the floor and may practice increased hand to mouth activity that may increase their dose-intake of specific contaminants that accumulate in dust and other matrices. Children are also smaller in size than adults, resulting in a greater body burden for a given contaminant dose. Because children undergo rapid transitions through particular developmental stages they are also especially vulnerable during certain growth-related time windows. A Special Issue was organized focused on the latest findings in the field of children’s environmental exposure for these reasons. This editorial introduces articles in this Special Issue and emphasizes their main findings in advancing the field. From the many articles submitted to this Special Issue from around the world, 23 were accepted and published. They focus on a variety of research areas such as children’s activity patterns, improved risk assessment methods to estimate exposures, and exposures in various contexts and to various contaminants. The future health of a nation relies on protecting the children from adverse exposures and understanding the etiology of childhood diseases. The field of children’s environmental exposures must consider improved and comprehensive research methods aimed at introducing mitigation strategies locally, nationally, and globally. We are happy to introduce a Special Issue focused on children’s environmental exposure and children’s health and hope that it contributes towards improved health of children.