The former employee, identified only as Choi, was in charge of the production and distribution of toxic raw materials for humidifier cleaners at SK Chemicals, Yonhap News Agency reported.
Former and current officials at SK Chemicals previously avoided punishment by claiming they didn't know the toxicity of humidifier cleaner raw materials, but the prosecution has secured circumstantial evidence suggesting they lied.
Prosecutors applied a charge of professional negligence resulting in death to Choi, and the Seoul Central District Court held a pretrial detention hearing on Choi on Friday.
The Ministry of Environment last month filed a complaint against two SK Group companies and their employees with prosecutors, accusing them of concealing crucial research results that indicate the toxicity of their raw materials for humidifier sterilizers. The ministry's complaint against SK Chemicals Co., SK Innovation Co. and their employees was submitted to the Seoul Central District Prosecutors' Office.
In the complaint, the ministry claimed the SK companies and employees attempted to destroy key evidence in the unfolding humidifier sterilizer scandal by failing to mention results of a 1994 study suggestive of the potential toxicity of sterilizer raw materials during a raid by ministry officials last year.
The complaint came after Hong Ji-ho, former president of SK Chemicals, and Park Cheol, senior vice president of SK Chemicals, were arrested in March on charges of destroying evidence on the toxicity of raw materials for humidifier sterilizers supplied to other local companies.
SK Chemicals, which was renamed SK Discovery in group-wide restructuring in 2017, manufactured key ingredients of humidifier sterilizers supplied to Oxy Reckitt Benckiser Korea and Aekyung Industrial, whose disinfectant products caused the deaths of about 100 consumers in South Korea.
Between 2006 and 2011, 73 people, including children and a pregnant woman, died of pulmonary disease, with a total of 181 consumers affected by the toxicity of a humidifier disinfectant sold by Oxy. The Supreme Court confirmed a six-year prison term for former Oxy chief Shin Hyun-woo last year on charges of accidental homicide due to professional negligence.
Aekyung's Humidifier Mate, produced between 2002 and 2012 with raw materials supplied by SK Chemicals, was accused of making 128 consumers sick and killing 27 of them.