Strong smell in North County unrelated to Escondido battery fire, officials say

SAN DIEGO (FOX 5/KUSI) — Residents across North County reported smelling a strong chemical scent outside Friday afternoon, with many taking to social media to speculate about its origin.

Those as far north as Oceanside and as far south as Encinitas said they began to encounter the odor around 5 p.m. in a flurry of posts on Twitter and Reddit. Some described it as "toxic" while others said it had a kind of smoke-like stench.

Many speculated that the smell blanketing North County was linked with a fire at a San Diego Gas & Electric-operated battery storage facility in Escondido, but San Diego County Air Pollution Control District officials said in a statement around 8:30 p.m. Friday that it was not related.

"Our field inspectors are on-site and have documented odors resembling a mix of plastic and asphalt/oil in certain areas but the odors dissipate quickly," the district continued. "Due to the fleeting nature of the odors, we have been unable to identify the source at this time."

An investigation remains ongoing into smell's origin. Hazmat teams were dispatched to the Interstate 5 corridor where the smell was reported for air sampling, Oceanside police said in a post on X around 6:20 p.m.

Environmental Protection Agency officials, the U.S. Coast Guard, county health and emergency services, and local officials also coordinated in efforts to respond to the stench reports.

An incident page through the county's emergency alert system, Alert San Diego, was launched around 6 p.m. to provide updates about the investigation into the stench. No further details were immediately available.

While the lithium-ion battery fire at the storage facility was ruled out as a contributor to the stench, strong fumes did impact part of North County on Thursday, as a mandatory evacuation warning was put in place for surrounding area.

"That's why we left, we couldn't stand the smell of it," one business owner told FOX 5/KUSI on Friday regarding the Escondido fire.

This is a developing story. Check back for updates.