SK Discovery, formerly SK Chemicals, and its former chief have been indicted on charges of false and exaggerated advertising over materials that suggested that a humidifier disinfectant containing toxic ingredients was harmless to humans.

The Seoul Central District Prosecutors' Office on Tuesday indicted SK Discovery and former CEO Hong Ji-ho on charges of violating the law on fairness of advertisements.

SK Discovery, which had manufactured the product, named "Home Clinic Humidifier Mate," allegedly colluded with seller Aekyung Industrial in issuing press releases in 2002 and in 2005, claiming the product was harmless and safe.

SK Discovery and its former CEO allegedly provided Aekyung with false information, despite being aware that CMIT/MIT, a main ingredient, could cause lung diseases or worsen existing conditions. They are accused of having such false information included in media reports until around September 2022.

Hong and former Aekyung chief Ahn Yong-chan, who was also indicted on charges of false advertising, are awaiting a top court ruling regarding their selling of the harmful substance.