PORT LOUIS: Sailing the world’s remotest seas in search of the awesome Sperm whale, the steel-hulled Odyssey has been dredging up some dark secrets about mankind’s damaging impact on the oceans.

A scientific research vessel circumnavigating the globe, the 93-foot (28 metres) sailing boat has been tracking the giant whales in the hope that they may hide in their bulk important clues to the state of the world’s seas.

The mission is not over, but the early indications are ominous. Pollutants, the debris of man’s life on land, have poisoned the waters that dominate the planet.

Working for the US-based Ocean Alliance, a whale conservation and research body, the Odyssey set out in March 2000 to quantify that toxicity, using tissue samples from Sperm whales to indicate how polluted the waters really are.

“We chose to study the toxicity levels in Sperm whales because they are one of the most abundant great whale species left on the planet and are found in all seas and oceans in the world,” said Genevieve Johnson, Ocean Alliance’s education director.

“We were surprised by the levels of pesticides like DDT found in our preliminary analysis of Sperm whale tissue samples.

“We have completed almost four years of our five year study and have so far taken tissue samples from about 900 sperm whales in various parts of the world.”

BANNED BUT WIDELY USED: An adult male Sperm whale can reach lengths of 18 metres (60feet) and weigh more than 60 tons. It is believed to be the biggest toothed predator in the world.