The party will also work with the government to conduct an overall inspection on all biocide type products that are currently being sold in South Korea.

The follow-up measures will be taken care of by the Prime Minister’s Office, instead of the current Environment Ministry, the officials said.

Families of the victims, and the members of the opposition parties, have been calling for parliamentary action to uncover those responsible and ensure compensation.

“The National Assembly will launch a parliamentary probe and hearing, and speed up its efforts to revise necessary regulations,” said Saenuri Party floor leader Rep. Chung Jin-suk.

“The government should also report (to the parliament) how products which were unauthorized in other countries could be sold in the local market, and check if any other hygiene products in sale are chemically safe,” he added.

The prosecutorial probe, meanwhile, is expected to widen to foreign officials of Oxy Reckitt Benckiser amid escalating public uproar over the massive number of deaths, sources said Sunday.

The Seoul Central District Prosecutors’ Office is reportedly setting up schedules over when to summon several foreign executive board members of Oxy, who are knowledgeable about the company’s operation.

These include two former CEOs -- John Lee, a 48-year-old Korean national with American citizenship, and a 47-year-old.

Lee served as the CEO from June 2005 to May 2010, succeeding Shin Hyun-woo who was summoned late last month. Sales of the problematic product surged while Lee was holding the post, the prosecution said. Lee is suspected of pushing ahead with the product sales despite continuous health complaints from users.

The second man, who worked from May 2010 for two years, is suspected to have been a key person who directed to conceal key evidence.

Prosecutors said that it was around the time he was holding a post in the company, that Oxy changed its corporation type and allegedly sought to manipulate Seoul National University’s experiment report over the product toxicity test.

The prosecution will also look into whether these former leaders served as a link between the Korean branch and the U.K. headquarters by sharing information and reports over the toxic product case, they added.

A Seoul National University professor surnamed Cho was arrested Saturday on charges of manipulating evidence in favor of Oxy. Cho, 57, is suspecting of making up an experiment report that is allegedly advantageous to Oxy’s stance over the product toxicity.

In an alleged attempt to refute the government’s health probe that pointed out humidifier disinfectant as the culprit behind more than a hundred deaths in 2011, the company had requested that Cho conduct a toxicity test of PHMG, the main ingredient of the humidifier disinfectant. Oxy allegedly handed over 250 million won ($216,000) to Cho for the experiment cost.

Toxicity was found in the initial reproduction-toxicity test but Oxy allegedly bribed Cho to release an inhalation-toxicity test report in favor of the company.

Prosecutors found that the company had sent a total of 12 million won to Cho’s personal account on three occasions, separate from the experiment fee.

In the following year, Cho released a health report that causality between the product use and the lung damage was not clear.

Cho denied the allegations and said the company had not asked him for such a favor.

Meanwhile, it was revealed that a 2013 report by the Korean Centers for Disease Control and Prevention showed that use of the humidifier disinfectant could increase lung risk by 116 times.

Based on a comparison between PHMG-exposed people and others under the same condition, the health agency confirmed that longer exposure to PHMG could lead to higher lung risks.

The report was not released to the public, citing that the result was similar to the government’s health probe result already released in 2011, the health authorities said.

The report was published in international science journal PLOS ONE in March this year.

Meanwhile, Kim Deok-jong, 40, a father who claims to have lost his son to Oxy’s humidifier sterilizer said Saturday he will file a compensation suit against the British company later this month. Kim had gone to the U.K. headquarters last week to urge CEO Rakesh Kapoor to visit Seoul and officially apologize

He said he decided to file the damage suit after the CEO refused his demand to visit South Korea to make an apology in front of the sterilizer’s victims. His 5-year-old son died in 2009 due to a respiratory disease.

The company, however, said in its press release that the CEO had sincerely apologized to them.

“Mr. Kapoor repeated his heartfelt apology to all those victims who used Oxy HS products in Korea and extends his apology to all victims. He confirmed his commitment to a full resolution announced by Ata Safdar in Korea last week,” the company said.

By Lee Hyun-jeong (rene@heraldcorp.com)