More than three dozen people were evacuated from nearby homes and businesses while the state DEP recovered the canister, which contained Methyltrichlorosilane, in an auxiliary parking lot, police Detective Sgt. Matthew Hoogmoed said.
The chemical, which is "highly flammable and reacts violently with water," Hoogmoed said.
"After the canister was punctured, it spilled a yellow tinted fluid into the dirt and a vapor cloud was released," the sergeant said. "The liquid that spilled from the canister began to violently react as well."
The fumes sickened a 40-year-old crew member, who bystanders said was taken to the hospital in an ambulance.
Wagaraw Road was closed from Lafayette to Lincoln avenues beginning around 1:45 p.m. with "no entry to the roadway whatsoever," Hawthorne police said.
Evacuations were also required.
A command center was set up at the Wagaraw Road ballfield, which was closed to practices for the rest of the day.
The roadway was reopened around 6 p.m. and evacuees were allowed to return.
Hawthorne police, firefighters and the Volunteer Ambulance Corps, responded, along with a Passaic County Hazardous Materials Unit, the Passaic County Health Department and Sheriff's Office and Valley Hospital EMS.
Michael Jannicelli took the photo and contributed to this account.
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