GENERAL Electric Co. said Thursday its investigators hadn’t been able to substantiate allegations of overworked employees and improper mercury exposure at its Chinese fluorescent lighting joint venture, Xiamen Topstar Lighting Co.

A study released by Cleveland, the United States-based nonprofit Policy Matters Ohio on Wednesday said that the plant’s workers endure 64-hour weeks and improper exposure to mercury.

GE immediately dispatched an environmental health and safety team to the facility, the Fairfield, the Connecticut-based company said.

“They are in the process of examining all of the allegations in the report,’’ spokeswoman Kim Freeman said in a statement.

“At this point, none of the allegations in the report have been substantiated, possibly making the allegations in the report untrue and reckless, needlessly damaging the good record of Topstar and GE,’’ she said.

The report, based on interviews with 35 workers, alleged that Xiamen Topstar Lighting violated Chinese labor laws and GE’s policies by exhausting employees, Zach Schiller, spokesman for the policy group, said Thursday.

“What we’ve reported stands on its own,’’ said Schiller. “I hope GE keeps an open mind in doing its investigation.’’

Xiamen Topstar, based in Xiamen, Fujian Province in southern China, makes compact fluorescent light bulbs that contain mercury.

GE, founded by incandescent bulb developer Thomas Edison, last year said it would cut 425 workers in Ohio as it shut plants and moved production overseas to pare costs. (SD-Agencies)