The La Porte Office of Emergency Management (LPOEM) said the Fire Department and the Harris County Pollution Control confirmed there were no "detectable amounts of immediately hazardous products" near or downwind the facility.

The announcement comes after officials had cautioned residents to shelter in place due to a phosgene leak at Altiva, a chemical manufacturer and transporter that develops phosgene derivatives for pharmaceuticals and the agriculture industry.

"Eight people were transported from Altivia due to exposure, and all were stable at the time of leaving the facility," said Houston County Judge Lina Hidalgo on a post on X, formerly known as Twitter.

Phosgene is a colorless gas with a suffocating odor like musty hay that is used in the manufacture of other chemicals, pesticides, and pharmaceuticals, according to the U.S. Centers for Disease Control and Prevention.

Exposure to phosgene gas may cause vomiting, breathing difficulty, chest pain and, in its liquid form, frostbite.

Halliburton's Multi-Chem Bayport site, Stepan's Pasadena facility, and three other sites belonging to Kuraray Americas, Evonik, and NCTI, also lifted orders to shelter in place, according to community alerts.

"There was no impact to any schools as they were not in the shelter area," LPOEM added.

An Altiva spokesperson did not immediately reply to requests for comment.

(Reporting by Deep Vakil and Rahul Paswan in Bengaluru; Editing by Chris Reese, ,Bill Berkrot and Aurora Ellis)