Apple has banned the use of benzene and n-hexane in the final assembly process of its products, after pressure from labour watch groups to safeguard the health of workers.
A four-month investigation was carried out by Apple in China after concerns about hazardous chemicals were raised by Green America and China Labor Watch.
The iPhone-maker said it visited 22 facilities, which collectively employ 500,000 people to make devices including the iPhone and iPad. Investigators carried out screening for benzene and n-hexane, evaluated protective equipment and checked ventilation.
"Our four-month investigation of our 22 final assembly plants found no widespread use of benzene or n-hexane, and no evidence of worker health and safety being put at risk from exposure to chemicals," Apple said in an online report.
Apple claimed that 18 out of the 22 facilities it inspected did not have any traces of benzene or n-hexane. However, the firm has taken steps to help safeguard the health of workers.
"First, we concluded that safer alternatives to these chemicals exist. So we have updated our RSS to explicitly prohibit the use of benzene and n-hexane in cleaning agents and degreasers in the final assembly process. We have also tightened our benzene restriction even further, to 0.1 ppm from 0.5 ppm."
Green America welcomed the news, but stressed Apple needs to do more to regulate chemical usage by second and third tier suppliers.
The non-profit organisation claims that Apple uses a total of 349 facilities in China, employing approximately 1.5 million people.
"Apple has investigated just 22 of these facilities (6.3 per cent) which employ a third of the workers who work on Apple's products," Green America said in a statement.
"This sample does not represent a cross-section of all of Apple's suppliers in China. Apple is still allowing benzene and n-hexane, and many other potentially hazardous chemicals, to be used in its second and third tier suppliers."
