Johannesburg — Biological testing proved that the white powder found at Sanral's operations centre in Pretoria on Tuesday was not anthrax, the Electronic Toll Collection (ETC) said.
Thirty seven people were decontaminated and hospitalised as a precautionary measure, ETC CEO Jamie Surkont said in a statement on Tuesday night.
The Tshwane hazardous material unit was called to the centre on Tuesday afternoon after a "suspicious envelope containing a white substance" was found on the premises.
This resulted in the shutdown of electricity there and the evacuation of the building.
"We treat this threat in a very serious light," said Surkont.
While Sanral said earlier that the evacuation had disrupted the Gauteng highway tolling system, Surkont said it remained operational and that there had been insignificant service interruptions at the call centre.
He said full services would be reinstated as soon as possible.