The Oregon Department of Environmental Quality and the Southwest Washington Clean Air Agency has issued an air quality advisory for the Portland-Vancouver metro area due to elevated levels of ozone pollution.
Ozone forms when hot temperatures and low winds combine with pollution from cars, gas-powered engines and chemicals in paints and aerosols. These air pollutants react with sunlight and heat to produce ozone and haze, which irritates the eyes, nose and lungs, and contributes to breathing problems.
The agencies expect ozone pollution to reach levels Monday afternoon that could be unhealthy for sensitive groups, including children, seniors, pregnant women and people with heart disease or respiratory conditions. Health officials recommend sensitive groups limit outdoor activity when pollution levels are high.
Ozone pollution increases throughout the day with exposure to sunlight, so pollution levels tend to be highest during afternoons and early evenings. Air quality monitors may show good air quality in the morning, then quickly jump to unhealthy levels later in the day.