Use of Urinary Creatinine to Assess Occupational Exposure as a Firefighter: A Preliminary Study

Recently, it was described that occupational exposure as a firefighter can causes bladder cancer. Although the creatinine is a renal biomarker commonly used in the diagnosis of acute kidney injury (AKI), the characterization of urinary creatinine changes in firefighters due to their active participation in fire events remains poorly characterized. An exploratory study was conducted to determine, for the first time, the urinary creatinine levels of 15 firefighter trainees during a controlled urban fire event. The range of urinary creatinine concentrations were slightly increased in the day after firefighting (48.76–308.03 mg/dL) than pre-fire levels (31.36–243.78 mg/dL). A total of 27% of firefighters presented an increase of, at least, 1.5 times in the urinary creatinine levels after participation in firefighting. Also, 6.7% of participants presented urinary levels of creatinine that exceeded the recommended guidelines (30–300 mg/dL). The findings of this preliminary study highlight the need to explore the relationship between urinary creatinine and kidney injury in firefighters. Further studies, with a superior number of individuals and including other biomarkers of early kidney damage are needed to characterize firefighters’ renal function and explore its relationship with exposure to health-relevant pollutants, heat, and associated physiological disorders (e.g., dehydration and muscle damage).