Residents of Los Angeles and surrounding areas enjoy vibrant fireworks displays for the Fourth of July, yet this tradition also carries serious health implications. When fireworks light up the sky, they leave behind pollutants that can impact both the environment and human health.

The South Coast Air Quality Management District reports that central and southern Los Angeles County, northern Orange County, and Riverside and San Bernardino counties will experience hazardous air pollution from 5 p.m. Saturday through 3 p.m. Sunday. Northern Los Angeles County and southern Orange County are also expected to face unhealthy air quality levels during this period.

Pollution levels are expected to build from dusk onward Saturday, as light winds and increased firework activity lead to an increase in smoke.

Exposure to firework-related pollution can lead to respiratory problems, asthma attacks, and cardiovascular issues. Los Angeles County Public Health advises individuals experiencing severe symptoms such as chest pain or difficulty breathing to seek immediate medical attention.

The proximity of pyrotechnics when set off at home heightens the risk of cardiovascular issues, according to the American Lung Association. July 4th and 5th are typically among the worst days for air quality in the region.

This year’s celebration follows a significant warehouse fire in Boyle Heights in late June, which released large amounts of soot and smoke comparable to the pollution caused by previous wildfires.

To mitigate health risks, Los Angeles County Public Health suggests limiting strenuous physical activity and keeping doors and windows closed. The use of air purifiers or air conditioners is recommended over fans and coolers that might draw pollutants indoors.