Characterization of occupational smoke exposure among wildland firefighters in the midwestern United States.

Wildland firefighters are repeatedly exposed to elevated levels of wildland fire smoke (WFS) while protecting lives and properties from wildland fires. Studies reporting personal exposure concentrations of air pollutants in WFS during fire suppression or prescribed burn activities have been geographically limited to the western and southeastern United States. The objective of this study is to characterize exposure concentrations of air pollutants in WFS emissions among wildland firefighters who conducted prescribed burns in the Midwest. Between 2016 and 2019, a total of 35 firefighters (31 males and 4 females, age of 35.63 ± 9.31 years) were recruited to participate in this study. Personal particulate matter 2.5 (PM2.5) and carbon monoxide (CO) exposure concentrations were measured during prescribed burns. The level of black carbon (BC) in WFS particulates was determined using the light transmission technique, while trace metal composition was analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The results showed geometric means for PM2.5, CO, and BC concentrations were 1.43 ± 0.13 mg/m3, 7.02 ± 0.69 ppm, and 58.79 ± 5.46 µg/m3, respectively. Although no occupational exposure limits (OELs) were exceeded by 8-h time-weighted average (TWA) exposure concentration observed in the firefighters, a total of 28 personal CO exposure concentrations were above the National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL) Ceiling (200 ppm) for CO. PM2.5 and CO concentrations were about 2-7 times higher in the Midwest than the other regions. Firefighters who performed holding had higher CO exposure concentrations compared to firefighters who performed lighting (p < 0.01), while lighters were exposed to higher level of BC in the smoke particulates (p < 0.01), possibly due to the domination of exposure by different combustion sources and stages. The levels of trace metals in WFS particulates were well below the corresponding OELs and no task-related difference was observed except for manganese. Our results suggest that wildland firefighters in the midwestern region have higher WFS exposures while working at prescribed burns compared to those western and southeastern United States.

Testing three explanations for stigmatization of people of Asian descent during COVID-19: maladaptive coping, biased media use, or racial prejudice?

OBJECTIVE: To investigate factors associated with the stigmatization of people of Asian descent during COVID-19 in the United States and factors that can mitigate or prevent stigmatization. DESIGN: A national sample survey of adults (N = 842) was conducted online between May 11 and May 19, 2020. Outcome variables were two dimensions of stigmatization, responsibility and persons as risk. Hierarchical regression analyses were performed. RESULTS: Racial prejudice, maladaptive coping, and biased media use each explained stigmatization. Racial prejudice, comprising stereotypical beliefs and emotion toward Asian Americans, was a stronger predictor of stigmatization than maladaptive coping or biased media use. Fear concerning the ongoing COVID-19 situation and the use of social media and partisan cable TV also predicted stigmatization. Low self-efficacy in dealing with COVID-19, when associated with high estimated harm of COVID-19, increased stigmatization. High perceived institutional efficacy in the handling of COVID-19 increased stigmatization when linked to high estimated harm of COVID-19. On the other hand, high perceived collective efficacy in coping with COVID-19 was associated with low stigmatization. More indirect contacts with Asians via the media predicted less stigmatization. CONCLUSIONS: Efforts to reduce stigmatization should address racial stereotypes and emotions, maladaptive coping, and biased media use by providing education and resources to the public. Fostering collective efficacy and media-based contacts with Asian Americans can facilitate these efforts.

Urinary mutagenicity and oxidative status of wildland firefighters working at prescribed burns in a Midwestern US forest.

OBJECTIVE: Wildland firefighters (WLFFs) experience repeated exposures to wildland fire smoke (WFS). However, studies about WLFFs remain regionally limited. The objective of this study was to assess the effect of WFS exposure on urinary mutagenicity and cell oxidation among WLFFs who work at prescribed burns in the Midwestern USA. METHODS: A total of 120 spot urine samples was collected from 19 firefighters right before (pre-shift), immediately after (post-shift), and the morning (next-morning) following work shifts on prescribed burn days (burn days) and regular workdays (non-burn days). The levels of urinary mutagenicity, 8-isoprostane, malondialdehyde and oxidised guanine species (Ox-GS) were measured. Linear mixed-effect models were used to determine the difference of cross-shift changes in the concentrations of urinary biomarkers. RESULTS: Post-shift levels of creatinine-corrected urinary mutagenicity and 8-isoprostane were non-significantly higher than pre-shift levels (1.16× and 1.64×; p=0.09 and 0.07) on burn days. Creatinine-corrected Ox-GS levels increased significantly in next-morning samples following WFS exposure (1.62×, p=0.03). A significant difference in cross-shift changes between burn and non-burn days was observed in 8-isoprostane (2.64×, p=0.03) and Ox-GS (3.00×, p=0.02). WLFFs who contained the fire (performed holding tasks) had a higher pre-morning to next-morning change in urinary mutagenicity compared with those who were lighting fires during the prescribed burns (1.56×, p=0.03). CONCLUSIONS: Compared with the other regions, WLFFs who worked in Midwestern forests had an elevated urinary mutagenicity and systemic oxidative changes associated with WFS exposure at prescribed burns.

Efficacy and Mediators of a Web-Based Media Literacy Intervention for Indoor Tanning Prevention.

Extant media literacy interventions have been delivered in person, limiting their potential for large scale reach, implementation, and dissemination. Although emerging evidence suggests the interventions can impact behavior, the theoretical mediators that can explain the efficacy remain unknown. This study investigated the efficacy and mediators of a web-based media literacy intervention for reducing indoor tanning behavior among young women. Participants were randomly assigned to one of three conditions: a media literacy intervention with counter argument production, a media literacy intervention with counter story production, or an assessment-only control condition. The outcomes of indoor tanning behavior and intention were evaluated with 3- and 6-month follow-ups. Results indicated significant effects of the web-based intervention on reducing indoor tanning behavior at the follow-ups. Changes in perceived media realism completely mediated the intervention effects on behavior. Perceived media realism, positive and negative outcome expectancies, and collective efficacy partially mediated intervention effects on intention. This study demonstrates the efficacy of a web-based media literacy intervention and the theoretical mechanisms underlying the efficacy. It indicates that by altering perceived media realism, outcome expectancies, and collective efficacy, web-based media literacy interventions could generate behavioral effects.

Measuring acute pulmonary responses to occupational wildland fire smoke exposure using exhaled breath condensate.

Wildland firefighters are directly exposed to elevated levels of wildland fire (WF) smoke. Although studies demonstrate WF smoke exposure is associated with lung function changes, few studies that use invasive sample collection methods have been conducted to investigate underlying biochemical changes. These methods are also either unrepresentative of the deeper airways or capable of inducing inflammation. In the present study, levels of biomarkers of oxidative stress (8-isoprostane) and pro-inflammatory response (interleukin-6 [IL-6], interleukin-8 [IL-8], C-reactive protein [CRP], and soluble intercellular adhesion molecule-1 [sICAM-1]) were determined in exhaled breath condensate (EBC) samples that were collected from firefighters before, after, and next morning following prescribed burn and regular work shifts. Results show only a marginal cross-shift increase in 8-isoprostane on burn days (.05 < p value < .1), suggesting WF smoke exposure causes mild pulmonary responses.