Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Are antifouling paints harming our sealife?

Are antifouling paints harming our sealife?


NIWA has recently completed a national project for modelling the leaching of copper from antifouling paints on vessels’ hulls.

NIWA’s modelling suggests that in many New Zealand marinas, copper concentrations could be above the guidelines for protection of marine aquatic life.

The port areas predicted to be at greatest risk are Nelson and the designated port area of Milford Sound in Fiordland, a world heritage area with high ecological value.

This modelling work was conducted for New Zealand’s Environmental Protection Authority (EPA), which assesses the risk of hazardous substances to the environment.

Antifouling paints are used to protect our environment by preventing unwanted organisms attaching themselves to the hulls of boats.

Copper is used in almost all antifouling paints on boats in New Zealand. These paints are designed to leach copper into the water column while vessels are in the water.

Copper leaching from moored vessels represents a potentially significant source of copper in the marine environment. Dissolved copper, the most harmful form to organisms, is measurable in water samples from marinas and ports around New Zealand. Significant copper inputs also come from stormwater discharges, with high concentrations often measured in harbour sediments.

An existing OECD model, the Marine Antifoulant Model to Predict Environmental Concentrations (MAM-PEC), was used by NIWA scientists to predict concentrations of antifouling compounds at 11 ports and 13 marinas around New Zealand.

A study to test the predictions for the Auckland area was undertaken by Auckland Council’s Stormwater Contaminant Scientist, Marcus Cameron, in collaboration with NIWA’s Dr Jennifer Gadd and principal scientist Dr Chris Hickey. The study measured copper in the water column of Auckland marinas.

Dr Hickey says, “When the measured copper concentrations were compared to the predicted concentrations there was generally overlap between the modelled and measured results.

“We have provided a robust modelling tool configured for New Zealand ports and marinas, which the EPA can confidently use for their antifouling assessment procedure.”

It will also assist the EPA in assessing the various antifouling paints approved for use in New Zealand waters.

“Based on the results from this study, and information compiled from previous studies, leaching of antifouling paints from vessel hulls appears to be the major source of copper in marina waters,” says Hickey.

In Auckland, where the validation study was done, the highest concentrations were measured at Westpark and Milford marinas, which are both also influenced by urban stormwater and marina hard-stand activities such as boat-washing, scraping and repainting.

Marcus Cameron says,"The results were quite surprising - the modelling indicated that copper levels could be quite elevated in marina waters and the sampling broadly confirmed that. On top of this the estimates of copper being exported from marinas were also significant, with as much copper exported from the four marinas in the Waitemata Harbour as from inputs of stormwater for the whole Waitemata Harbour catchment."

The lowest concentrations were measured at Bayswater Marina. Bayswater has floating walls, while the other marinas primarily use solid walls and have small entrances which restrict tidal flows.

"Even though these results were surprising, they are still comparable to results from studies overseas where in some cases leaching from antifouling paints on vessel hulls has been found to be the dominant source of copper in the marine environment," says Cameron.

The EPA is currently carrying out a reassessment of antifouling paints approved for use in New Zealand.

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Must Sell 20 Petrol Stations: Z Cleared To Buy Caltex Assets

Z Energy is allowed to buy the Caltex and Challenge! petrol station chains but must sell 19 of its retail sites and one truck-stop, the Commerce Commission has ruled in a split decision that acknowledges possible retail price coordination between fuel retailers occurs in some regions. More>>

ALSO:

Huntly: Genesis Extends Life Of Coal-Fuelled Power Station To 2022

Genesis Energy will keep its two coal and gas-fired units at Huntly Power Station operating until 2022, having previously said they'd be closed by 2018, after wringing a high price from other electricity generators who wanted to keep them as back-up. More>>

ALSO:

Dammed If You Do: Ruataniwha Irrigation Scheme Hits Farmer Uptake Targets

Enough Hawke's Bay farmers have signed up for water from the proposed Ruataniwha Water Storage Scheme for it to go ahead as long as a cornerstone institutional capital investor can be found to back it, its regional council promoter announced. More>>

ALSO:

Reserve Bank: OCR Stays At 2.25%

Reserve Bank governor Graeme Wheeler kept the official cash rate at 2.25 percent, in a decision traders had said could go either way, while predicting inflation will pick up as the slump in oil prices washes out of the data and capacity pressures start to build in the economy. More>>

ALSO:

Export Values Down: NZ Posts Biggest Annual Trade Deficit In 7 Years

New Zealand has recorded its biggest annual trade deficit since April 2009, reflecting weaker prices of agricultural commodities such as dairy products, beef and lamb, and increased imports of vehicles and machinery. More>>

ALSO:

Currency Events: NZ's New $5 Note Wins International Banknote Award

New Zealand’s new Brighter Money $5 note has been named Banknote of the Year in a prestigious international competition. The $5 note was awarded the IBNS Banknote of the Year title at the International Bank Note Society’s annual meeting. More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news