Several elementary students in Autauga County are recovering from reactions to a potential chemical leak near school grounds on Friday.

A chemical truck passed by Pine Level Elementary School as students played outside during physical education class, video footage reviewed by school officials showed. About six minutes later, a group of about 40 students began experiencing facial swelling and watery eyes, said Daniel Boyd, the district’s interim superintendent.

“All of the kids who were sick are doing much better,” Boyd told AL.com on Saturday morning. “They’re doing OK.”

School officials contacted the local emergency management agency and fire department Friday and concluded their investigation Saturday morning, ruling out an off-campus fire as a possible source of exposure. They also confirmed that the playground area and buildings had no presence of poisons or toxins.

“Based on video review of activity and traffic patterns in the area, the conclusion is that a commercial truck traveling along Highway 31 may have had an accidental chemical leak near the school, and, with yesterday’s weather pattern, the wind carried it to the playground,” read a statement posted on the school’s website Saturday morning.

The fire department hosed down all playground equipment, and the campus has been cleared for students to return next week.

In its notice Saturday, the school noted a few reports of lingering symptoms and asked parents to consult a doctor if any reactions got worse.

District leadership on Friday spoke with the families of the students who had adverse reactions, but Boyd said he wanted to wait to release details to the public until the investigation concluded.

“There’s really nothing to hide, it’s just that we can’t give them information we don’t have,” he said. “It takes time to test the air and inspect the building and do all those particular things.”

Below is the full statement from Pine Level Elementary:

“Thank you for your patience as ACS worked to pull all data sources together for a comprehensive synopsis. Yesterday’s incident has been confirmed as environmental by the proper authorities. They later determined the off-campus fire was only releasing carbon dioxide, ruling it out as a possible source of exposure. The playground area and buildings were also confirmed to have no presence of poisons or toxins. Based on video review of activity and traffic patterns in the area, the conclusion is that a commercial truck traveling along Highway 31 may have had an accidental chemical leak near the school, and, with yesterday’s weather pattern, the wind carried it to the playground. As an extra precaution, the fire department hosed down all playground equipment, and the campus has been cleared for students to return next week. District leadership has spoken with the families of the students who had adverse reactions, and thankfully the initial symptoms have subsided. There are still only reports of minor reactions to a small population of the groups outdoors during the possible exposure. Common reactions include itching, burning, and stinging eyes, throats, and skin. Parents are encouraged to consult a healthcare provider if any unusual symptoms present this weekend and contact Mrs. Harry to record the exposure.”