TAIPING: Investigations into the appearance of "black dust" on surfaces of items in Tekkah here are being conducted, says Perak Environment Department (DOE) director Datuk Dr Mohammad Ezanni Mat Salleh.
Dr Mohammad Ezanni said the DOE has received five reports of the incident last week.
He said the incident is believed to have affected about 100 homes in Taman Tekkah Permai and Taman Tekkah Jaya.
"Observations at the locations found that no odour, smoke, dust or open burning occurred.
"And based on our analysis of the air quality between Aug 6 and 11, we found two dominant gas readings, which are hydrogen cyanide and acetylene, which is produced from pyrolysis of tyres," he said in a press conference held at state environment committee chairman Teh Lok Lim's service centre here on Tuesday (Aug 12).
"The highest data collected was on Aug 7, with the permitted amount of gas emission having exceeded the standard Malaysian Air Quality Index reading.
"We've also carried out monitoring using drones within a 5km radius of the complaint location but did not find any traces of open burning or premises releasing pollution into the air in the monitored area," he added.
Mohammad Ezanni said the DOE had checked about 30 premises in a nearby industrial area in Kamunting.
"As of now, one premises is our primary suspect.
"We have taken samples of the substance from the affected residents' homes and the premises involved and sent it to a chemical laboratory in Petaling Jaya to be analysed," he said, adding that the emission of the black dust may have been due to a malfunction of pollution control equipment.
"If the samples match, we will take action against the premises," he added.
Teh said the situation has now stabilised, but urged residents in the areas affected to continue being vigilant.
"Please ensure the windows are closed when the wind blows. All cooking equipment should also be cleaned thoroughly," he said.
