This spring, Green America’s End Smartphone Sweatshops campaign, in partnership with China Labor Watch (CLW), called on Apple to remove toxic chemicals including benzene and n-hexane from its supplier factories in China. Only five months into the campaign, Apple announced in August that it would “explicitly prohibit the use of benzene and n-hexane” at 22 of its final-assembly supplier factories.

“If you’ve ever wondered if signing a petition can really make a difference, now you know. With 23,000 signatures since March of 2014, we’ve been able to push one of the biggest companies in the world to change its practices,” says Elizabeth O’Connell, Green America’s campaigns director.

A known carcinogen, benzene can cause leukemia, a blood cancer, and leukopenia, a dangerously low white blood cell count.The chemical n-hexane is a neurotoxicant that can cause nerve damage and paralysis after long-term exposure. As reported in the April/May Green American, workers in electronics supplier factories—including those making Apple products—use both chemicals to clean touch screens. Undercover CLW representatives have found such workers using little to no protective equipment, with inadequate safety training.

In a statement released August 13th, Lisa Jackson, former EPA Secretary and current Apple vice-president of environmental affairs, stated that Apple had investigated 22 final-assembly supplier factories that make iPhones, iPads, iPods, and Mac computers, “and found no evidence of workers’ health being put at risk from exposure to [benzene and n-hexane].”

O’Connell, however, says the campaign’s work is not over. “Benzene and n-hexane are still allowed in factories that produce the components for iPhones and iPads,” she sas. “Beyond benzene and n-hexane, there are thousands of chemicals used in electronics manufacturing—some which are largely untested—and many chemicals used by Apple suppliers remain undisclosed. Apple needs to do more to protect workers.”

With production set to ramp up this fall with the release of the iPhone 6, Green America and CLW are now calling on Apple to extend the chemical ban to substances other than benzene and n-hexane, and to all of its supplier factories, including early-production facilities where chemical usage and safety measures are less controlled.

In July, the campaign also began targeting Samsung, after news broke that five children below the age of 16 and many minors between 16 and 18 were found working in Shinyang Electronics Co., Ltd., one of its Chinese suppliers. Workers are also exposed in Samsung’s factories to toxins like benzene and n-hexane.

Sign our new petition to Apple, as well as our petition to Samsung and demand they take action to protect all workers across their supply chains.