The mysterious balls that forced the closure of several Sydney beaches last week contained saturated acids, E. coli and faecal bacteria, authorities say.
Sydney’s Northern Beaches Council said it had sent the debris to the New South Wales Environmental Protection Authority (EPA) for further analysis.
Nine beaches, including popular Manly and Dee Why, were closed on January 14 after the marble-sized balls began washing ashore.
It came months after thousands of black spots began appearing on the city’s shores in October, prompting authorities to close some of its most famous beaches for several days and order a massive cleanup.
The last batch of bales was cleared from the harbor beaches this week, the Northern Beaches Council said in its statement on Tuesday.
He urged anyone who spotted the bullets not to handle them and to contact authorities.
Besides acids and bacteria, the balls also contained volcanic pumice.
Northern Beaches Mayor Sue Heins said she hoped the EPA’s analysis would “identify the source so they can prevent this from happening on other beaches”.
“We continue to regularly inspect our beaches and encourage the community to report any sightings,” she said.
The first batch of debris in October was initially mistakenly called “tar balls,” but was later found to contain everything from molecules of cooking oil and soap scum up to blood pressure medications, pesticides, hair, methamphetamine and veterinary drugs.
Scientists said they resemble blobs of fat, oil and grease – often called “fatbergs” – which commonly form in sewage systems.
But Sydney Water said its water treatment plants were operating normally and there were no known problems with wastewater treatment systems in the city.
