The incident occurred at a plant in Shanghai, according to a one-sentence report released by the country's state news agency. It did not provide any other details.
Industrial accidents are common in China due to lax safety and building standards.
The Shanghai government information office said the accident happened at a plant in the Baoshan district of the east coast city, and that six of those injured were in serious condition. It added that rescue work at the plant was over and the cause of the leak was not known.