Particle exposure level and potential health risks of domestic Chinese cooking

Cooking oil fumes (COF) contain massive particulate matter. Chronic exposure to cooking oil fumes constitutes a health hazard. This study aims to measure the COF exposure level during a typical Chinese domestic cooking process and evaluate whether a short-term exposure at this level entails deleterious cardiopulmonary, inflammatory health effects and oxidative stress. 6 young healthy students were recruited to conduct a contrast experiment in a kitchen chamber. Every participant cooked successively three typical Chinese dishes twice a day for two consecutive days, during which the particle mass and number concentration in the breathing zone were monitored. A slot around the pan supplied air at varied rates during cooking, resulting in altered exposure dose. Before the experiment and after their cooking, the levels of biomarkers were measured including 8 biomarkers for lung function, fractional exhaled nitric oxide for respiratory inflammation, blood pressure for cardiovascular risks and three biomarkers in urine for oxidative stress. PM2.5concentration and particle number concentration in 0.02–6.25 μm were 10.97 ± 9.53 mg/m3and 23.12 ± 18.27 103/cm3in the breathing zone under normal ventilation condition and might triple under poor ventilation. Health measurements showed that forced vital capacity and vital capacity declined significantly after the fourth cooking process. Peak expiratory flow rose significantly after the third cooking. Meanwhile, forced expiratory flows at 25% of the vital capacity also increased significantly after both the third and fourth cooking. However, a single short-term exposure to COF of around 20 min does not explicitly entail significant health risks.