Prosecutors are expanding their investigation into allegations that the British firm Oxy Reckitt Benckiser concealed negative lab test results involving its sterilizing product for humidifiers.
 
An official from the prosecution said Friday that investigators will look into speculation raised by an exclusive KBS report about a research team at Seoul National University's veterinary college that examined the toxicity of Oxy's sterilizer. The official said prosecutors will look into whether the company attempted to destroy evidence.
 
At Oxy's request, a research team at SNU conducted lab tests and released a report in November 2011. Test results showed that unborn babies of pregnant mice who were exposed to the sterilizer died in the womb.
 
The research team at the time said that the sterilizer could be toxic and that more tests were necessary. However, Oxy is confirmed to have left out the test results concerning the pregnant mice in a letter of opinion submitted to prosecutors in 2014.
 
Based on official government tally so far, some 140 South Koreans have died after using the sterilizer. With the investigation picking up steam, manufacturers have begun issuing apologies.