Effective measures should be taken immediately to stop worsening pollution in the sea off South China's Guangdong Province, experts said.

A recent research report by the Guangdong provincial oceanic and fishery administration, showed that the seawater quality of the affluent province has been deteriorating each year since the first study in 2001.

Based on data from 75 observation stations in the near-shore areas of 13 coastal cities, the research showed that the Pearl River estuary, Shantou in East Guangdong and Zhanjiang port in Southwest Guangdong, had fallen into the category of "seriously polluted".

Pollutants such as inorganic nitrogen, phosphate and petroleum have been found in the areas, which could cause harmful red tides.

Tests also found that the sea's sullage contained lead, copper, cadmium, mercury, arsenic and petroleum.

In the Pearl River estuary, the ecology system has been destroyed and cannot be rectified in the short-term, the report said.

"It's a result of neglect by local governments. They spend generously on improving the water quality of rivers, but not much on the protection of oceans," said Li Zhujiang, director of Guangdong Provincial Oceanic and Fishery Administration, at a recent press briefing.

Industrial, agricultural and urban waste are to blame for the pollution, he said.

The province monitored 112 land source sewage outlets last year and found 84, or 75 percent, of the outlets had discharged pollutants higher than the permitted level.

About 8.3 billion tons of sewage from 82 outlets was discharged into the sea last year, up more than 60 percent from 5 billion tons five years ago, according to the Guangdong Monitoring Centre on Oceanic and Fishery Environment.

The centre estimated that 12.6 tons of pollutants had been discharged from the province into the sea last year.

Three sewage outlets in Dongguan, which borders Guangzhou, have been cited for discharging excessive pollutants into the sea.

Li suggested the provincial government update regulations for land-to-sea sewage because present regulations were outdated, having being enforced a decade ago.

Apart from increasing financial resources, Li said cities in the province should also sign letters of commitment to curb pollution.

A researcher surnamed Zhang, with Guangdong Ocean University, told China Daily that it is never to late to clean the sea.

"It's an inevitable result of economic growth. Local governments have always pursued economic growth at the expense of the environment, no matter if it is land or sea," Zhang said.

He said the governments should attach greater importance to limiting the discharge of new pollutants into the sea.

Xia Zhen, a professor with Guangzhou Marine Geological Survey, said the governments should stop the unnecessary reclamation of land, which indirectly causes seawater pollution.

The coastal cities in Guangdong have claimed nearly 6,700 hectares from the sea in the past few years. This has reduced the area of the Pearl River estuary, and raised seawater levels, Xia said.

Editor: Yan