Only three of China's 74 major cities met state pollution standards last year, according to the 2013 China Environmental Situation Report.

Haikou, Zhoushan and Lhasa were the least polluted while Beijing, neighboring Tianjin and cities in north China's Hebei Province were the worst.

Of the 10 cities that suffered the most serious problems, seven were in Hebei, including the worst three — Xingtai, Shijiazhuang and Handan.

Beijing residents breathed "good" air on just 175 days last year.

In Shanghai, environmental authorities said the city had 241 "good" days.

At a press conference ahead of today's World Environment Day, Li Ganjie, vice minister of environmental protection, quoted the report as saying that although China's environment had improved in general, water quality is "not optimistic" and air quality in cities is "serious."

In China's top 10 river valleys in 2013, about 9 percent of the water sections was class V, the worst level. Of 4,778 monitoring sites for groundwater almost 60 percent were poor or extremely poor.

Water quality offshore was not good either, according to the report, with 18.6 percent of offshore water areas only reaching class IV. Water quality in the East China Sea and in four of China's nine biggest bays was extremely poor.

As for air quality in cities, accumulation of air pollutants such as sulfur dioxide and nitric oxide led to acid rain which mostly affected areas along the Yangtze River, especially the southern side of the middle and lower reaches, around 10.6 percent of the nation's land.

Soil pollution and land degradation are also serious, according to Li, who said arable land had been reduced by 80,200 hectares in 2013, and a total of 295 million hectares, or 30.7 percent of China's land area, was suffering soil erosion.

China's soil was found to be mainly polluted by industrial and agricultural activities. About 82.8 percent of the polluted land was contaminated by inorganic materials with the top three pollutants cadmium, nickel and arsenic.

The wide use of antibiotics in the animal husbandry industry also raised pollution risks.

Zhou Shengxian, minister for environmental protection, told Xinhua news agency that emissions of major pollutants had dropped in the past year.

For example, chemical oxygen demand emissions reduced by 2.9 percent, while emissions of sulfur dioxide dropped by 3.5 percent, but compared to 2012, the percentage of class V water quality in the 10 major river basins dropped by only 1.2 percentage points.

As for air quality in cities, a five-year action plan in 2013 put forward 35 integrated measures. The plan stipulated cuts in coal use and the density of inhalable particulate matter, as well as the closure of polluting enterprises.

In April, a revised law on environmental protection was approved, stipulating environmental protection as a basic policy, and prioritizing protection over development.

Zhou said he wants to improve the legal system to establish more strict supervision of environment issues, and address pollution of water, air and soil.

Li said the ministry sees water, air and soil pollution as major tasks, adding that action plans will address water and soil pollution as soon as possible.

Better handling of the interplay between economic development and environmental protection was also needed.