Occupational Exposure to Ultrafine Particles (UFPs) in Pizzerias: Personal Monitoring and Comparison of Oven Technologies

Background: Ultrafine particles (UFPs) represent a significant occupational health concern in commercial cooking environments, yet comprehensive exposure assessment in pizzerias remains limited despite their global prevalence and unique cooking processes. Understanding UFP exposure patterns and associated health effects in this widespread food service sector is crucial for protecting worker health. Objective: To quantify occupational exposure to airborne UFPs among pizzeria workers across different oven technologies. Methods: A cross-sectional observational study was conducted in 10 pizzerias in the Cagliari metropolitan area (April 2022–March 2024), encompassing wood-fired ovens (WFO, n = 6), electric ovens (EO, n = 3), and mixed systems (BO, n = 1). Ventilation characteristics were documented at each site to evaluate their influence under real-world operating conditions. Personal UFP exposure was measured using DISCmini diffusion size classifiers (10–700 nm range), while qualitative particle characterization employed ELPI+ impaction with SEM-EDS analysis. Results: UFP concentrations varied dramatically by oven type, with median values of 3.18 × 10⁴ particles/cm³ (WFO), 1.29 × 10⁵ particles/cm³ (EO), and 2.55 × 10⁵ particles/cm³ (BO). Seven of ten pizzerias exceeded WHO precautionary limits (20,000 particles/cm³), with electric oven facilities showing concentrations comparable to high-emission industrial operations. Elemental analysis revealed predominantly carbon-based particles with significant iron, aluminum, and silicon content, indicating combined combustion and mechanical abrasion sources. Conclusions: Pizzeria workers experience substantial UFP exposure levels that frequently surpass those in other food service environments and approach levels typically observed in high-exposure industrial workplaces. Electric ovens generate significantly higher UFP levels than wood-fired systems, likely due to ventilation efficiency differences.