The Ministry of Environmental Protection received nearly 15,000 public tip-offs about pollution in 2015, with air pollution dominating the complaints, it said on Tuesday.

All the complaints were lodged through the telephone hotline "12369" and an official WeChat account.

Among 1,145 complaints received through the hotline, 78.3 percent were related to air quality, a 3.3-percent year-on-year decrease, said the ministry, adding others involved water and noise pollution.

The industries subject to most complaints were chemicals, non-metallic mineral processing, metal smelting and processing, accounting for 57 percent of air pollution tip-offs lodged by telephone.

The rest 13,719 complaints were received through the official WeChat account which was opened in June 2015. Among the 10,176 cases handled, 7,001 were about air pollution, accounting for 68 percent of the total WeChat tip-offs.

Others involved water, noise, solid waste and radiation pollution, the ministry added.