Sydneysiders planning to have some fun in the sun have been cleared to return to the city’s beaches after thousands of strange black balls washed up on shore.
After conducting preliminary tests on the balls, scientists from the University of NSW found they were not toxic and instead contained bituminous materials and some biological material such as fatty acids.
But the good news is somewhat tempered by the forecast from the Bureau of Meteorology, which predicts gray clouds will linger over the port city, with a 70 per cent chance of rain on Saturday, before clearing on Sunday.
It comes as seven beaches in Sydney were closed to the public after black tar balls washed up on the sand earlier this week.
Despite the large-scale removal of thousands of balls, NSW Maritime director Mark Hutchings urged the community to remain vigilant if they head to the beach this weekend.
“Based on advice from the EPA, we can now confirm that the balls consist of fatty acids, chemicals similar to those found in cleaning and cosmetic products, mixed with some fuel oil,” Hutchings said.
‘They are not harmful if left on the ground, but should not be touched or picked up.
‘We expect to see thousands of people heading to our beaches this weekend as the rain starts to clear.
Sydney beachgoers will be relieved to get back in the water after beaches were declared safe to reopen
‘If you see these balls, report them to a lifeguard. If you or your family accidentally touch one, wash your hands with soap and water or baby oil.”
NSW EPA director Stephen Beaman said investigations into the origin of the balls were continuing.
‘Until we have completed all our test results we cannot clearly state where they come from and what any environmental impact they may have – it is still a bit of a mystery and it may take a few more days to determine the origin .
‘We remind anyone who finds these balls, especially in new locations that have not yet been identified, to report them to the Environment Line on 131 555.’
Ms Beaman said people should check with their local council whether the beaches are open or not.
2,000 ‘unusual’ bulbs were discovered for the first time along Coogee Beach on Tuesday, prompting Randwick City Council to immediately close the beach while tests were carried out.
Tests by scientists at the University of NSW found the tar balls were not highly toxic to humans
Since then, Gordons Bay, Clovelly Beach and Maroubra Beach have been closed to the public after tar balls also washed ashore.
Bondi, Tamarama and Bronte beaches were also closed ‘as a precaution’, Waverley City Council said.
With fewer than 150 balls left on some beaches, Hutchings said a coordinated multi-agency approach would continue to investigate the bizarre items.
“We’ve had teams on the ground, ships on the water and drones in the air to clear most of the balls from our beaches,” he said.
‘We have found no further evidence of the substance so this appears to be an isolated incident.
“We continue to monitor the situation, but at this stage NSW Maritime is reducing the risk and advising councils that beaches can be open.”
Councils have the final authority on whether or not to reopen beaches.
UNSW chemist Alex Donald said the findings confirmed the tar balls came from weathered oil.
Seven beaches in Sydney were closed while the clean-up operation continued
“It is still unclear whether they are the result of natural seepage or a crude oil spill,” he said.
‘Further chemical analysis is needed to determine the source.’
The researchers also placed the balls under UV radiation.
The dots on the balls are fluorescent, indicating organic compounds.
The tar balls “likely originated from petroleum-based sources.”
‘Whether caused by human activity or natural processes, solving the mystery of these persistent invaders requires continued scientific research.’
“The source could be related to oil spills, petrochemical processes or environmental pollution involving hydrocarbons,” Professor Donald said.
The fluorescence indicates that marine algae are attaching.
Similar balls appear on California coasts due to oil seeping from the seafloor. Golden Beach in Queensland and Ninety Mile Beach in Gippsland have seen similar stains, following oil spills or ship discharges.
Professor Donald said it was important to find out whether the tar balls came from a spill or naturally from the seabed, in shaping the appropriate environmental response.
Clean-up operations started on Wednesday to remove debris from popular beaches and remove it safely
An industrial spill can lead to legal action and requires immediate cleanup.
“The toxins in tar balls can leach into water and pose a long-term threat to marine biodiversity,” he said.
‘The appearance of tar balls on beaches like Coogee not only damages Australia’s pristine coastal reputation, but also threatens the health of ecosystems that support industries such as fishing and tourism.’
The six UNSW scientists will continue to analyze the balls, receiving samples from Randwick City Council.
Randwick Mayor Dylan Parker said the council would continue to remove the material from all beaches.
“The safety of the community is our first priority. Council has therefore taken the precaution of closing these beaches whilst we undertake the safe collection and disposal of this material.
‘We do not yet know what has happened to the debris washing up on our beaches, but we will continue to work with the relevant authorities to ensure the safety of the public and to keep our beaches clean.’
Preliminary results showed that the material of the ‘unusual’ spheres was a ‘hydrocarbon-based contaminant consistent with the composition of tar balls’.
Clean-up operations started on Wednesday to remove debris from popular beaches and remove it safely.
The mayor said council staff had been working with the NSW Environment Protection Agency, Ports Authority and Transport for NSW to assist with the clean-up effort.
The cleanup process is expected to continue through Thursday, Mayor Parker advised.
“Our community is rightly very protective of our natural environment and this has been a deeply concerning incident,” he said.
“We have engaged an expert industrial hygienist and specialist waste removal contractor who are currently systematically removing debris from the beaches in accordance with an agreed safe working practice statement developed in partnership with the NSW EPA.”
He thanked the public for staying off the beach while testing and clean-up work continues.