Essex — A fire at Calamari Recycling Co. Inc. at 20 Dump Road continues to burn and produce smoke conditions in the area, a fire official said.

Four air samples taken Thursday at the site of the fire at the recycling facility have not detected levels of toxic compounds hazardous to public health, the state Department of Energy and Environmental Protection said Thursday.

DEEP Emergency Response crews, wearing protective gear, entered the metal structure where the fire was located to collect air samples, and also sampled the air just outside the building, on the same property, and downwind at the Essex fire station, DEEP said in a news release.

The sample from within the structure had trace amounts of "various indicator chemicals," but all were below levels deemed a risk to public health, DEEP said.

No toxins were detected in the sample taken from town.

The other two samples are still being analyzed, DEEP said, but levels of toxins are expected to be lower than those found in the sample from inside the building.

DEEP said two water samples were taken from an unnamed brook on the property that flows into Ward Brook. Results are expected Friday.

DEEP said no petroleum sheen was visible on the watercourse and no distressed wildlife was observed.

The agency advised people who live near the site to avoid visible smoke from the fire.

Unburned particles can be harmful, especially to those with respiratory ailments, DEEP said.

Fire Marshal Keith C. Nolin said the fire was reported at 2:35 p.m. Wednesday inside a building used to recycle construction debris.

He said mostly wood scraps are dumped inside the building, and personnel sort out any metal or other products from the wood. The scrap wood is then trucked to the Trash to Energy Plant in Hartford.

Nolin said fire officials have not been able to go inside the building, but they have discovered the area of the origin of the fire, which he did not disclose.

"When we can enter the building safely, we will be looking to find the exact point of origin and the cause," Nolin said.

Firefighters from more than a dozen departments battled for hours to bring the three-alarm fire under control Wednesday.

Fire crews were still at the scene Thursday morning, putting out flare-ups and using excavators to move materials and properly douse them.

The building was destroyed in the fire.

First Selectman Norman Needleman praised the mutual aid agreement that the town shares with local fire departments.

"We had more than 12 fire chiefs here last night who coordinated with our fire chief," Needleman said. "I can't tell you how important they were to us in getting this fire under control."

No injuries were reported, he said.

According to Calamari's website, the company sits on 14 acres in Essex and employs more than 25 full-time workers.

Primarily a metals recycling facility, it also handles materials from appliances and asphalt to flooring and insulation.

The company relocated to Essex from New London in 1999 after development of the Fort Trumbull peninsula in the city.

Known as Calamari Brothers Co. Inc. at the time, the company's former property on Trumbull Street cost the public about $9 million to clean up before Pfizer Inc. built the office building now occupied by Electric Boat, according to The Day archives.

Dennis Schain, spokesman of the state DEEP, said the agency sent an emergency response unit Wednesday to the fire scene.

He said the unit was observing firefighting operations and was consulting with local officials. It was also assessing any potential environmental risks.

On Wednesday night, northeast winds were favorable and carried much of the smoke from the fire out toward the Connecticut River to sparse areas of population, but conditions Thursday changed, and smoke from the fire was being carried over downtown Essex, he said.

"Efforts to fight the fire did involve large amounts of water and there was much runoff toward the Connecticut River ... sometimes in fires like this remnants of petroleum products are caught up in such runoff, but our staff did not observe that happening in this situation," he said.

Needleman confirmed that smoke had been seen in the downtown.

State police reopened Exit 4 on Route 9 northbound at 4:50 a.m. after it was closed for more than 12 hours to prevent motorists from driving near the fire scene.

i.larraneta@theday.com

Twitter: @larraneta