"The accumulated scientific evidence indicates that the impacts of nodule mining in the Pacific Ocean would be extensive, severe and last for generations, causing essentially irreversible damage," the report, commissioned by the Deep Sea Mining Campaign and MiningWatch Canada, found.

Polymetallic nodules are potato-sized lumps formed by layers of iron and manganese hydroxides around a core in the seabed and contain cobalt, nickel, copper, manganese that are used in batteries where demand is constantly rising in high-tech industries.

The report also warned against unrealistic expectations in the Pacific where many island states are cash strapped, rely on Australian aid and are already feeling the effects of climate change and rising seas and temperatures.

"Expectations that nodule mining would generate social and economic gains for Pacific island economies are based on conjecture," it said. "The impacts of mining on communities and people's health are uncertain and require rigourous independent studies."

The Pacific Ocean covers 30 per cent of the earth's surface and the report says it is the new frontier for mining with companies and investors driving a speculative rush for mineral deposits - and there are foreign policy implications for Australia.

The 52-page report entitled "Predicting the Impacts of Mining Deep Sea Polymetallic Nodules in the Pacific Ocean" provides a scientific consensus based on 250 peer reviewed scientific and other related articles.

It added: "The interconnected nature of the ocean means that impacts would be felt region wide".

It says deep sea mining will have severe and long-lasting impact on fish species and could pose significant risks to marine ecosystems more broadly while the impact on fisheries, communities and human health are largely unknown and thus pose risks.

Sperm whales, whale sharks, Leatherback turtles and bird life could be at risk from nutrient enrichment and metal toxicity caused by waste discharge as much as the commercial end which includes tuna an other fish catches.

"Costs of deep sea nodule mining in the Pacific Ocean are likely to outweigh the asserted but unsubstantiated benefits," it said.

Hence, a moratorium is being urged to allow further studies.

Last year Canadian company Nautilus Minerals went bankrupt, scuppering a deep sea mining project that cost PNG about $A183 million. That came soon after Australia announced to would commit $A300 million in direct budget assistance for its northern neighbour.

Australia is also expected to provide $A336 million through its Pacific Regional Program over the current financial year.

To date, the International Seabed Authority (ISA) - tasked by the United Nations - has issued 30 international exploration licenses, 25 in the Pacific Ocean and 18 of those in the Clarion Clipperton Zone which stretches from Kiribati to Mexico.

European, Japanese and Korean companies are among the most prominent alongside Australian company Bluewater Metals, according to the ISA.

However, the report was also critical of the ISA which it says has stated that a 20-year mining operation would impact an area of 8,500 square kms.

"But there is no publicly available research indicating how much sediment would be suspended during mining or how mine waste would be treated and released," the report said.

"One study estimated that a mining operation could discharge up to 50,000 tonnes of sediment laden-water per day," it added.

Australian Associated Press