Updates to this story
Optoelectronics company Wintek issued a statement intended to re-assure shareholders that its house is in order.
Last week we reported that one of its employees at its Chinese factory in Suzhou called for an investigation into the company's practice.
Wintek had used the poison n-hexane to clean Apple components, including iPhone touch screens.
Wintek released a statement to the Taiwan bourse yesterday about the incident. It said that the incident using n-hexane in August 2009 was now resolved.
"At the time of the incident, Wintek immediately enacted a number of effective improvement measures that are still under implementation including the immediate removal of n-hexane from the production lines. All affected workers were then screened and medical treatment has been provided to all personnel who were affected by the exposure and they are now recuperating or have returned to their jobs," the statement said.
Wintek further said that n-hexane is widely used for cleaning in the electronics industry and is not on the national list of highly toxic substances.
But, Wintek continued, "when persons come into contact with n-hexane for extended periods of time in poorly ventilated spaces, symptoms such as fatigue, numbness of the limbs and peripheral neuritis can appear. In severe cases, it can also lead to neuronal damage. However, if the affected people are given the proper treatment, they can successfully recover from n-hexane exposure. As a result, companies need to take effective occupational health protection measures when using n-hexane."
It acknowledged that some employees at its wholly owned subsidiary United Win in Suzhou became ill at the beginning of August 2009.
"Our company made it our top priority to ensure that the affected personnel received well medical treatment and take corrective actions in internal management," the statement said.
Those actions included stopping using n-hexane, giving employees with personal protective equipment, improving ventilation, and measuring airborne chemicals.
Wintek has carried out six inspections since August 5th 2009, and checked for n-hexane and that acetone and other chemicals were within occupational health standards.
It has ensured anyone affected by n-hexane were given prompt treatment. The affected employees have recovered or are in the process of recovering, Wintek claimed.