Scientists hope a new study will prove the Bay of Plenty environment has fully recovered from the Rena disaster, which spilled approximately 350 tonnes of oil into the ocean.

Research team Te Mauri Moana began a project this week to assess the progress of recovery among a variety of marine species during the last eight months.

Scientists are hoping the Bay environment has bounced back after the Rena oil spill eight months ago.

Scientists have been surprised by the low levels of contamination after tracking the accumulation of toxic elements in the tissues of shellfish such as tuatua and pipi, and found the toxic levels have returned to normal.

Group leader professor Chris Battershill says the spill was effectively managed in the early stages, when salvors gathered the majority of the off-shore oil and volunteers reduced the amount left on beaches.

Without the work of both parties the local environment would not be approaching full recovery, he says.

'I think the worst is over for the oil pollution.

'Now we need to check for other potential pollutants, trace metals, plastics, PCB's etc.”

Research will reveal if contaminants have moved through the marine food chain and whether any damage has been done to reproductive ability.

Chris says the research supplies the group with a rare opportunity, as it has in its possession data on the affected areas both before and after the spill.

The group, consisting of academics and students from the University of Waikato, Bay of Plenty Polytechnic, Te Whare Wananga o Awanuiarangi and the University of Canterbury, is one of the largest projects within the $3 million Rena recovery programme.