LA PORTE, Texas (KXAN) — An evacuation order is still in effect for areas around a chemical plant in La Porte, officials said Wednesday.

The La Porte Office of Emergency Management said a half-mile radius around 13300 Bay Area Blvd., the address for Dow Chemical, needed to be evacuated, as crews responded to a “process upset” call. There are other chemical plants in the area, too.

In a statement to NBC-affiliate KPRC, Dow Chemical said the incident involved a tank wagon venting the chemical Hydroxy Ethyl Acrylate, which is used in acrylics for coating and adhesives. It can cause irritation of the nose and throat, and in liquid form, can irritate eyes and skin.

KPRC reports Dow Chemical stated the venting has stopped, and now emergency personnel are monitoring the tanker truck to find out if the reaction is decreasing or increasing.

Earlier shelter-in-place orders for areas east of Bay Area Boulevard outside of the evacuation zone were lifted around 10:45 a.m. Wednesday. Officials asked people to turn off their air conditioning units while they stayed indoors.

La Porte is east of Houston along Galveston Bay.

Officials don’t know if any chemicals or harmful fumes are in the area.

We will have more information on the incident as it becomes available.