Philippines launches investigation into Chinese sewage-dumping at sea

The Philippines has launched an investigation against hundreds of Chinese vessels that were dumping sewage into contested areas of the South China Sea.

"While we are confirming and verifying these wastes being dumped ... we consider such irresponsible acts, if true, to be gravely detrimental to the marine ecology in the area," Philippine Defence Secretary Delfin Lorenzana said in a statement.

"Despite conflicting claims and interests by states in the South China Sea, all nations must be responsible stewards of our natural resources and environment."

The Philippines has become more vocal in recent months over the presence of hundreds of vessels it believes are Chinese maritime militias.

It comes after a report by US-based tech firm Simularity Inc showed swarms of Chinese vessels had dumped human waste and wastewater for years in a disputed area of the South China Sea, causing algae blooms that have damaged coral reefs and threatened fish in an unfolding catastrophe.

The company had released satellite images over the last five years, showing how human waste, sewage, and wastewater have accumulated and caused algae in a cluster of reefs in the Spratlys region where hundreds of Chinese fishing ships have anchored in batches.

Liz Derr, who heads Simularity Inc, a software company creating artificial intelligence technologies for satellite imagery analysis, said the waste could threaten fish stocks.

China, which is engaged in hotly-contested territorial disputes in the South and East China Seas, has made substantial progress in militarising its man-made islands in the past few years.

Beijing claims sovereignty over all of the South China Sea. But Vietnam, Malaysia, the Philippines, Brunei, and Taiwan have counterclaims. In the East China Sea, China has territorial disputes with Japan.

Both maritime areas in the South and East China seas are rich in minerals, oil, and other natural resources and are also vital to global trade.

(With inputs from agencies)