Workers at a Chinese factory believed to make electronic components for tech giants like Apple and Nokia are back on the job after a violent strike to protest what they believe was deadly on-the-job exposure to toxic chemicals...Protesters said they believe four co-workers died from exposure to a toxic chemical...Neither Wintek, which is based in Taiwan, nor Apple, responded to requests for comment...Wintek’s refusal to address the toxins issue seemed to feed the factory rumor mill.... “We heard a girl died in a strange manner from chemicals at the Suzhou factory, but we weren’t allowed to talk about it,” said an employee of the Dongguan factory...“They said anyone who talked about it would be fired.”... Workers at subcontracting factories...often don’t know who they’re making parts for, and typically have no means to complain to...brands about labor violations.