# Quantification of Volatile Organic Compounds (VOCs), Nitrogen Oxides (NO x ), and Ultrafine Particles (UFPs) Emitted by Domestic Air Fryers: A Chamber Study of Indoor Air Quality Impacts

## TL;DR

This study measures indoor air pollutants like VOCs, NOx, and UFPs emitted by air fryers during cooking, finding significant variation based on food type and fryer usage.

## Contribution

The study quantifies pollutant emissions from air fryers and identifies factors like food type and fryer residue affecting indoor air quality.

## Key findings

- Pollutant emissions varied with food type, with high-fat foods producing UFPs comparable to deep frying.
- Residues in the air fryer after multiple uses increased VOC and UFP emissions even when no food was cooking.
- NOx was only detectable during cooking certain foods and not during empty appliance runs.

## Abstract

Air frying has emerged as a popular low-oil cooking method,
yet
its impact on indoor air pollutant emissions remains insufficiently
understood. In our study, emissions of volatile organic compounds
(VOCs), nitrogen oxides (NO
x
), and ultrafine
particles (UFPs) were measured during the air frying of 12 different
dishes within a ca. 0.15 m3 Perspex chamber. Pollutant
emissions varied significantly depending on the food type, with rates
in the ranges of 17.8–184.0 μg min–1 for total cooking VOCs, 24.6–37.9 μg min–1 for NO
x
, and 0.1–17.4 ×
1012 # min–1 for UFPs, primarily due
to Maillard reactions and lipid thermal decomposition. While pollutant
concentrations and ozone formation potentials were elevated within
the chamber, scaling to the volume of a small kitchen indicated substantially
lower levels compared to conventional frying methods. Notably, only
high-fat foods produced UFP concentrations comparable to those of
deep frying. No NO
x
emissions were found
during blank (empty appliance) runs, and NO
x
was only detectable while cooking certain types of foods.
However, residues accumulating within inaccessible areas of the air
fryer following over 70 uses led to increases of 23% in VOC and 236%
in UFP concentrations while not cooking food.