Lessons from Dairy Farmers for Occupational Allergy and Respiratory Disease

PURPOSE OF REVIEW

Exposure to bioaerosols at dairies has long been associated with allergy, respiratory disease, and decreases in lung function. Recent advancements in exposure assessments have aided our understanding on the size distribution and composition of these bioaerosols, but investigations focusing solely on exposures may overlook important intrinsic factors impacting worker's susceptibility to disease.

RECENT FINDINGS

In our review, we discuss the most recent studies examining the exposures and genetic factors that contribute to occupational disease in dairy work. We also review more recent concerns in livestock work associated with zoonotic pathogens, antimicrobial resistant genes, and the role of the human microbiome. The studies highlighted in this review demonstrate the need for further research to better understand bioaerosol exposure-response relationships in the context of extrinsic and intrinsic factors, antibiotic-resistant genes, viral pathogens, and the human microbiome to help inform effective interventions that improve respiratory health among dairy farmers.

Assessing the Impact of Wildfires on the Use of Black Carbon as an Indicator of Traffic Exposures in Environmental Epidemiology Studies

Epidemiological studies frequently use black carbon (BC) as a proxy for traffic-related air pollution (TRAP). However, wildfire smoke (WFS) represents an important source of BC not often considered when using BC as a proxy for TRAP. Here, we examined the potential for WFS to bias TRAP exposure assessments based on BC measurements. Weekly integrated BC samples were collected across the Denver, CO region from May to November 2018. We collected 609 filters during our sampling campaigns, 35% of which were WFS-impacted. For each filter we calculated an average BC concentration. We assessed three GIS-based indicators of TRAP for each sampling location: annual average daily traffic within a 300 m buffer, the minimum distance to a highway, and the sum of the lengths of roadways within 300 m. Median BC concentrations were 9% higher for WFS-impacted filters (median = 1.14 μg/m3, IQR = 0.23 μg/m3) than nonimpacted filters (median = 1.04 μg/m3, IQR = 0.48 μg/m3). During WFS events, BC concentrations were elevated and expected spatial gradients in BC were reduced. We conducted a simulation study to estimate TRAP exposure misclassification as the result of regional WFS. Our results suggest that linear health effect estimates were biased away from the null when WFS was present. Thus, exposure assessments relying on BC as a proxy for TRAP may be biased by wildfire events. Alternative metrics that account for the influence of "brown" carbon associated with biomass burning may better isolate the effects of traffic emissions from those of other black carbon sources.

Wildfire Smoke Is Associated With an Increased Risk of Cardiorespiratory Emergency Department Visits in Alaska

Alaskan wildfires have major ecological, social, and economic consequences, but associated health impacts remain unexplored. We estimated cardiorespiratory morbidity associated with wildfire smoke (WFS) fine particulate matter with a diameter less than 2.5 μm (PM2.5) in three major population centers (Anchorage, Fairbanks, and the Matanuska-Susitna Valley) during the 2015-2019 wildfire seasons. To estimate WFS PM2.5, we utilized data from ground-based monitors and satellite-based smoke plume estimates. We implemented time-stratified case-crossover analyses with single and distributed lag models to estimate the effect of WFS PM2.5 on cardiorespiratory emergency department (ED) visits. On the day of exposure to WFS PM2.5, there was an increased odds of asthma-related ED visits among 15-65 year olds (OR = 1.12, 95% CI = 1.08, 1.16), people >65 years (OR = 1.15, 95% CI = 1.01, 1.31), among Alaska Native people (OR = 1.16, 95% CI = 1.09, 1.23), and in Anchorage (OR = 1.10, 95% CI = 1.05, 1.15) and Fairbanks (OR = 1.12, 95% CI = 1.07, 1.17). There was an increased risk of heart failure related ED visits for Alaska Native people (Lag Day 5 OR = 1.13, 95% CI = 1.02, 1.25). We found evidence that rural populations may delay seeking care. As the frequency and magnitude of Alaskan wildfires continue to increase due to climate change, understanding the health impacts will be imperative. A nuanced understanding of the effects of WFS on specific demographic and geographic groups facilitates data-driven public health interventions and fire management protocols that address these adverse health effects.

Print media coverage of California's smokefree bar law

OBJECTIVE

To assess the print media coverage of California's smokefree bar law in the state of California.

DESIGN

Content analysis of newspaper, trade journal, and magazine items.

SUBJECTS

Items regarding the smokefree bar law published seven months before and one year following the implementation of the smokefree bar law (June 1997 to December 1998). Items consisted of news articles (n = 446), opinion editorials (n = 31), editorials (n = 104), letters to the editor (n = 240), and cartoons (n = 10).

MAIN OUTCOME MEASURES

Number and timing of publication of items, presence of tobacco industry arguments or public health arguments regarding law, positive, negative, and neutral views of opinion items published.

RESULTS

53% of items published concerning the smokefree bar law were news articles, 47% were opinion items. 45% of items regarding the smokefree bar law were published during the first month of implementation. The tobacco industry dominated coverage in most categories (economics, choice, enforcement, ventilation, legislation, individual quotes), except for categories public health used the most frequently (government role, tactics, organisational quotes). Anti-law editorials and letters to the editor were published more than pro-law editorials and letters. Region of the state, paper size, presence of local clean indoor air legislation, and voting on tobacco related ballot initiatives did not have an impact on the presence of opinion items.

CONCLUSIONS

The tobacco industry succeeded in obtaining more coverage of the smokefree bar law, both in news items and opinion items. The tobacco industry used historical arguments of restricting freedom of choice and economic ramifications in fighting the smokefree bar law, while public health groups focused on the worker protection issue, and exposed tobacco industry tactics. Despite the skewed coverage, public health groups obtained adequate attention to their arguments to keep the law in effect.

The new battleground: California's experience with smoke-free bars

OBJECTIVES

This study examined the tobacco industry's tactics in the political, grassroots, and media arenas in attempting to subvert California's smoke-free bar law, and the efforts of health advocates to uphold and promote the law by using the same 3 channels.

METHODS

Interviews with key informants involved in the development and implementation of the smoke-free bar law were conducted. Information was gathered from bill analyses, internal memoranda, tobacco industry documents, media articles, and press releases.

RESULTS

The tobacco industry worked both inside the legislature and through a public relations campaign to attempt to delay implementation of the law and to encourage noncompliance once the law was in effect. Health groups were able to uphold the law by framing the law as a health and worker safety issue. The health groups were less successful in pressing the state to implement the law.

CONCLUSIONS

It is possible to enact and defend smoke-free bar laws, but doing so requires a substantial and sustained commitment by health advocates. The tobacco industry will fight this latest generation of clean indoor air laws even more aggressively than general workplace laws.