Three of the jailed men were environmental inspectors who allowed industrial plants to skirt inspections and discharge contaminants into the Longjiang River, the official Xinhua News Agency reported.
Zeng Juefa, the former vice president of the city's environmental protection bureau, was sentenced to 4 1/2 years in prison for taking bribes and delinquency, court officials said.
Lan Qunfeng and Wei Yei, the former heads of an environmental inspection team, were both sentenced to three years and six months in jail on the same charges.
The court found Guangxi Jinhe Mining Co. Ltd. a polluter and fined the company $162,997.
The company's three managers were each sentenced to three years in jail, Xinhua reported.
Seven managers of another polluter, Hongquan Lithophone Material Co., were sentenced to three to five years in jail.
The pollution began in April 2011, but was not discovered until January 2012, when dead fish were found floating in the river.
Investigators found that concentrations of a cadmium, a carcinogenic chemical, in the river were 80 times the official standard.