Apple will ban two potentially hazardous chemicals during the final assembly of its iPhones and iPads.
The decision came five months after labour activist group China Labour Watch and the environmental group Green America launched a petition urging the technology company to stop using the potentially harmful chemicals, benzene and n-hexane.
Apple said a four-month investigation at 22 factories found no evidence that benzene and n-hexane were endangering the roughly 500,000 people who work at the plants.
Despite this, the company has ordered its suppliers to stop using both chemicals during the final assembly of iPhones, iPads, iPods, and various accessories.
It will also ask all of its factories to test substances for benzene and n-hexane.
"This is doing everything we can think of … to crack down on chemical exposures and to be responsive to concerns," said Lisa Jackson, Apple's vice president of environmental initiatives.
"We think it's really important that we show some leadership and really look towards the future by trying to use greener chemistries." Benzene is a carcinogen that can cause leukaemia if not handled properly and n-hexane is a neurotoxin that has caused problems with workers' motor function, and is linked to headaches and nausea, according to Geoffrey Crothall, a spokesman for China Labour Bulletin.
"Basically workers were hospitalised for long periods of time after exposure to the two," Crothall said.
Suzhou Wintek, a major supplier of components for Apple's iPhone and iPod touch, illegally used n-hexane solvent instead of alcohol to wipe mobile phones, resulting in poisoning among its staff in 2010.
More than 49 employees at Wintek showed symptoms of n-hexane poisoning and were treated at a Suzhou hospital.
"Workers have to be aware of any potential hazards they're working with," Crothall said.
"In the case with the n-hexane poisoning in Suzhou, workers were simply not aware of the dangerous substance until they fell ill.
"The most important thing is that existing regulations on health and safety and the prohibitions of certain chemicals are enforced by local authorities."