Over the past few months, the Korean government has been pressured to look into the water quality of the nation’s four largest rivers as bryozoans were found to have formed colonies after the river refurbishment project started in late 2008.

Amid a series of allegations raised by environmental protection advocates, the Ministry of Environment has launched a full-fledged probe into the rivers ― the Hangang, Geumgang, Yeongsangang and Nakdonggang ― to investigate the emergence of bryozoans, known as moss animals.

The Ministry of Environment announced Tuesday that it would “resolve needless misunderstanding and debates by carrying out a probe on the animal from July to November.” The ministry also said it plans to review cases in foreign countries.

Before the probe, the ministry clarified that there have been no reports from the academic community, which has warned of the moss animals’ toxicity. A moss animal is a 0.5- to 1-millimeter-long aquatic invertebrate that generally lives in brackish water.

“Though pundits have shown little concern, the government aims to prevent needless debates from spreading further and calm down public worries,” it said in a statement.

Before the unveiling of its investigation, the ministry took the tentative stance that the species lived not only in contaminated areas but also in clean water. It also argued that that the moss animal was not harmful to humans.

The basic debate began with the advocates’ claim that detection of the moss animal means that some regions of the rivers are contaminated.

“Accordingly, apart from the toxicity of the moss animal, the government should focus its probe more on the water quality,” said a spokesman for the Incheon unit of the Korean Federation for Environment Movement.

He said the government should verify whether bryozoans are really found also in clean water as it stated in its earlier remarks.

Environmental advocates say that bryozoans do not usually inhabit flowing water. As the water flow has been slowed by the refurbishment project, they appear to have flourished in various regions along the four major rivers, according to the advocates.

Meanwhile, some conservatives say that the debate should not be politicized, alleging that some advocates are trying to tarnish the image of the refurbishment project led by the administration of former President Lee Myung-bak.

Oh Se-ho, a director of the state-run K-water, said it was necessary for the media to refrain from fostering concern among the public.

“The worries should be based on scientific research and overseas cases,” he wrote in a contribution to a newspaper. He claimed that the moss animals do not form colonies in contaminated water, citing theses from some universities.

A government official said he echoed the view among liberals that “the Lee administration’s controversial four rivers project, which struggled to gain full backing from politicians and environmentalists, is estimated to have greatly benefited the wallets of builders involved.”

However, he stressed that issues involving the water quality should be determined through scientific research.

By Kim Yon-se (kys@heraldcorp.com)