Tar balls: mystery substance on beaches could be linked to sewage plant, scientists say

Scientists examining petroleum-based balls believed to have come from an oil spill off Sydney as Bondi beach reopens

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Scientists analysing the black debris that closed Sydney beaches this week believe the tar balls" are likely from an oil spill but have not ruled out a link to a nearby sewage treatment plant.

Bondi, Bronte and Tamarama beaches reopened on Friday after they were closed along with several other eastern suburbs beaches when the mysterious dark spheres washed up on the sand. The balls were first spotted at Coogee beach on Tuesday afternoon.

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