Allergic disease associations with regional and localized estimates of air pollution.

BACKGROUND: Exposure to multiple types of air pollution may contribute to and exacerbate allergic diseases including asthma and wheezing. However, few studies have examined chronic air pollution exposure and allergic disease outcomes among an adult population. Associations between potential estimates of annual average fine particulate matter (PM2.5), traffic related air pollution, and industrial source air emissions and three allergic disease outcomes (asthma, allergies and wheezing) were examined in a state-wide general population of adults. METHODS: The study includes a representative sample of 3381 adult Wisconsin residents who participated in the 2008-2013 Survey of the Health of Wisconsin (SHOW) program. Participant data were geographically linked to The United States Environmental Protection Agency (USEPA) Baysian space-time downscaler air pollution model for PM2.5, the United States Census roadway, and USEPA's Toxic Release Inventory data. Self-report and lung function (FEV1) estimates were used to define prevalence of asthma, allergies and wheezing symptoms. RESULTS: Annual mean exposure to fine particulate matter (PM2.5) was between 6.59 and 15.14µg/m3. An increase of 5µg/m3 in the annual mean PM2.5 resulted in a 3.58 (2.36, 5.43) increase in the adjusted odds (95% CI) of having asthma. Exposure to vehicle traffic increased the odds of both current allergies [OR (95% CI)=1.35 (1.07, 1.35)] and current asthma [OR (95% CI)=1.51 (1.14, 2.00)]. Living within 300m of an Interstate roadway was associated with a 3-fold increase in the odds of asthma. Those living within 800m of an industrial site were 47% more likely to have asthma. No significant associations were seen with wheezing. CONCLUSIONS: Within this population exposed to overall annual average levels of estimated low level chronic exposure to fine particulate matter (PM2.5) at or near 12µg/m3, the USEPA standard for air quality, significant association between both modeled PM2.5 exposure and proximity to roadways with asthma and allergies but not wheezing were found. Industrial source emissions were not associated with any allergic disease outcomes.

Impact of ambient fine particulate matter carbon measurement methods on observed associations with acute cardiorespiratory morbidity.

Elemental carbon (EC) and organic carbon (OC) represent a substantial portion of particulate matter <2.5 µm in diameter (PM2.5), and have been associated with adverse health effects. EC and OC are commonly measured using the National Institute of Occupational Safety and Health (NIOSH) method or the Interagency Monitoring of Protected Visual Environments (IMPROVE) method. Measurement method differences could have an impact on observed epidemiologic associations. Daily speciated PM2.5 data were obtained from the St Louis-Midwest Supersite, and St Louis emergency department (ED) visit data were obtained from the Missouri Hospital Association for the period June 2001 to April 2003. We assessed acute associations between cardiorespiratory ED visits and EC and OC from NIOSH and IMPROVE methods using Poisson generalized linear models controlling for temporal trends and meteorology. Associations were generally similar for EC and OC from the different measurement methods. The most notable difference between methods was observed for congestive heart failure and EC (for example, warm season rate ratios (95% confidence intervals) per interquartile range change in EC concentration were: NIOSH=1.06 (0.99-1.13), IMPROVE=1.01 (0.96-1.07)). Overall, carbon measurement method had little impact on acute associations between EC, OC, and ED visits. Some specific differences were observed, however, which may be related to particle composition.

Outdoor air pollution activities at the Wisconsin State Laboratory of Hygiene.

Outdoor air quality testing at the Wisconsin State Laboratory of Hygiene (WSLH) began in the 1970s with the advent of the federal Clean Air Act. Since then, air quality has emerged as a major environmental issue equal to or more important, from a public health standpoint, than water pollution. Epidemiological studies have shown that health issues are not limited to highly urbanized areas. In Wisconsin, local climatic conditions caused by the Great Lakes can result in unhealthy conditions even in relatively pristine areas. Air pollution affects thousands of Wisconsin residents each year, and it can be severe enough to require a physician's care. Although certain air testing (e.g., ozone) is done regionally by in situ monitors, the WSLH analyzes a variety of air pollutants including ozone precursor hydrocarbons, air particulates, and toxic metals. Exposure to aerosols containing metals may not follow typical patterns of air pollution based on routinely monitored particle mass.