Abstract 25: Per- and polyfluoroalkyl substances and obesity in Florida firefighters

Background/Objective: Per- and polyfluoroalkyl substances (PFASs) are hazardous synthetic chemicals that have been linked to adverse human health effects such as cancer and endocrine disruption. Firefighters have been shown to be occupationally exposed to PFAS through aqueous film-forming foam (AFFF) used during difficult-to-suppress fires, and in the textile liners of their safety turnout gear. PFASs have both hydrophobic and hydrophilic chemical structures, giving them strong thermal stability and making them resistant to environmental and physiological degradation. Studies of human exposures to PFAS have observed associations between some PFAS and increased risk of obesity or elevated body mass index (BMI). Given the unique occupational exposures of firefighters to PFAS, we examine the association between obesity and PFAS in a sample of Florida firefighters.

Methods: A cross-sectional study design was used to collect a health survey and a blood sample from a non-probabilistic sample of career Florida fighters between June and October 2021. The health surveys, administered on REDCap using tablet devices, assessed information on firefighter socio-demographic and work characteristics. We quantified 7 distinct PFASs using a solid-phase extraction-high-performance liquid chromatography-isotope dilution-tandem mass spectrometry approach; the limit of detection was between 0.5 and 0.05 ng/mL, depending on the analyte. All 7 PFASs, including Perfluorobutanesulfonic Acid (PFBS), Perfluoroheptanoic Acid (PFHpA), Perfluorohexanesulfonic Acid (PFHxS), Perfluorooctanoic Acid (PFNA), Perfluorononanoic Acid (PFNA), Perfluorooctanesulfonic Acid (PFOS), and Perfluoroctanesulfonamide (PFOSA), were detected in the blood samples; concentrations below the limit of detection were replaced by the limit of detection/√2.35.

Results: Among the 208 firefighters who completed the survey and provided a blood sample, 92.8% were male, 16.2% Hispanic/Latinx, 81.7% White, 89.8% used AFFF at their fire department, with a group mean age 40.2±10.3 standard deviation. Approximately 15.8% of firefighters were of healthy weight, 51.5% overweight, and 32.7% obese. Firefighter body mass index was positively correlated with serum concentrations of PFHxS (rs=.17;p=.020) and PFBS (rs=.60;p=.26). Group geometric mean of each PFAS congener (in ng/mL): PFBS (0.09), PFHpA (0.08), PFHxS (2.17), PFOA (1.38), PFNA (0.42), PFOS (2.69), and PFOSA (0.10). Total serum PFAS concentrations was highest among obese firefighters (7.62 ng/mL) and lowest in healthy weight firefighters (6.55 ng/mL).

Conclusions: Firefighters who were overweight and obese, based on body mass index, had higher total serum PFAS concentrations than those firefighters of healthy weight. Both long- and short-chain PFASs, PFHxS and PFBS respectively, were positively correlated with firefighter body mass index.

Citation Format: Alberto J. Caban-Martinez, Paola Louzado Feliciano, Simi Oduwole, Natasha Schaefer Solle, Catalina Gonzalez-Umana, Thomas Stone, Erin N. Kobetz. Per- and polyfluoroalkyl substances and obesity in Florida firefighters [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 25.

Incidence of SARS-CoV-2 infection among COVID-19 vaccinated and unvaccinated healthcare personnel, first responders, and other essential and frontline workers: Eight US locations, January-September 2021

BACKGROUND

We sought to evaluate the impact of changes in estimates of COVID-19 vaccine effectiveness on the incidence of laboratory-confirmed infection among frontline workers at high risk for SARS-CoV-2.

METHODS

We analyzed data from a prospective frontline worker cohort to estimate the incidence of COVID-19 by month as well as the association of COVID-19 vaccination, occupation, demographics, physical distancing, and mask use with infection risk. Participants completed baseline and quarterly surveys, and each week self-collected mid-turbinate nasal swabs and reported symptoms.

RESULTS

Among 1018 unvaccinated and 3531 fully vaccinated workers, the monthly incidence of laboratory-confirmed SARS-CoV-2 infection in January 2021 was 13.9 (95% confidence interval [CI]: 10.4-17.4), declining to 0.5 (95% CI -0.4-1.4) per 1000 person-weeks in June. By September 2021, when the Delta variant predominated, incidence had once again risen to 13.6 (95% CI 7.8-19.4) per 1000 person-weeks. In contrast, there was no reportable incidence among fully vaccinated participants at the end of January 2021, and incidence remained low until September 2021 when it rose modestly to 4.1 (95% CI 1.9-3.8) per 1000. Below average facemask use was associated with a higher risk of infection for unvaccinated participants during exposure to persons who may have COVID-19 and vaccinated participants during hours in the community.

CONCLUSIONS

COVID-19 vaccination was significantly associated with a lower risk of SARS-CoV-2 infection despite Delta variant predominance. Our data demonstrate the added protective benefit of facemask use among both unvaccinated and vaccinated frontline workers.

Perceptions of Work-Related Health and Cancer Risks Among Women Firefighters: A Qualitative Study

OBJECTIVES

We use a qualitative method to gain further insight into women firefighters' experiences, perceptions of cancer, health, and safety risks in the fire service.

METHODS

We conducted six focus groups with U.S. women firefighters. Participants engaged in a 60 to 75-minute, semi-structured discussion and completed a sociodemographic questionnaire. A qualitative descriptive approach was used to inductively create themes. Data collection concluded when saturation was met.

RESULTS

Forty-nine women firefighters participated. Qualitative results indicated the main health concerns include: occupational cancer risks including, risks related to hazardous exposures, sleep disruption and stress; and women's health concerns including, cancer, pregnancy and breastfeeding, and lack of resources.

CONCLUSIONS

Women firefighters are concerned about their risk for cancer due to their occupation and identify a lack of resources specific to health and safety needs of women firefighters.

Objective Measurement of Carcinogens Among Dominican Republic Firefighters Using Silicone-Based Wristbands

PURPOSE

Firefighters around the world are exposed to physical hazards and toxic chemical agents during fire incident response. Occupational epidemiologic studies of the firefighter workforce have documented an excess cancer risk for brain, digestive, genitourinary, and lymphohematopoietic organs compared with the general population. Despite the elevated cancer risk, little is known about what specific types of carcinogenic chemicals first responders encounter during a typical work shift, particularly in low-resources settings, like the Dominican Republic. This pilot study characterizes objective measurements of carcinogenic exposure using passive sampling silicone-based wristbands among Dominican firefighters.

METHODS

Firefighters from a metropolitan fire service in the Dominican Republic were asked to wear a silicone-based wristband during one typical 24-hour shift. A pre- and postshift survey was administered to the firefighter to assess their self-reported sociodemographic, employment, and work shift characteristics. Wristbands were collected after their 24-hour shift and processed for the type and quantity of polycyclic aromatic hydrocarbons (PAHs), a family of known carcinogenic compounds, to which firefighters were exposed.

RESULTS

Among 15 firefighters who wore a wristband during their 24-hour shift, 73.3% responded to a fire with an average of 3.7 calls during the shift. Fire incident responses included structural fires (54.5%), outside and other fires (36.4%), and vehicle fires (9.1%). Total PAH exposure was significantly higher among Dominican firefighters who responded to a fire compared with firefighters with no fire during their shift (261 parts per billion [ppb] v 117 ppb, respectively; P = .003). Among the 19 PAHs quantified, low-molecular-weight phenanthrene was present in the highest concentration (32 ppb) among firefighters not responding to fires.

CONCLUSION

Passive objective sampling of PAHs using silicone-based wristbands among Dominican firefighters showed direct exposure to carcinogenic compounds during a typical 24-hour firefighter shift. Firefighters not attending a fire had lower levels of PAHs, suggesting carcinogenic contaminants are present at the fire station.