Scientists have identified the neon orange 'goo' that washed up in a village in northwest Alaska.
According to the scientists from the National Oceanic and Atmospheric Administration (NOAA), the substance is made up of microscopic eggs.
Originally it was thought that the 'goo', which appeared in the harbour at Kivalina last week, might be some form of algae.
"We now think these are some sort of small crustacean egg or embryo, with a lipid oil droplet in the middle causing the orange colour," said Jeep Rice, a lead NOAA scientist at the Juneau lab, said in a release. "So this is natural. It is not chemical pollution; it is not a man-made substance.
"It was easy to see cellular structure surrounding the lipid droplet, and to identify this as 'animal'," Rice added. "We have determined these are small invertebrate eggs, although we cannot tell which species."
Because scientists are still not sure what species is responsible for the eggs, they may still be toxic and this continues to worry the residents of the tiny hamlet of Kivalina.
Apparently there have been reports of dead minnows found in the village's lagoon the night the eggs appeared.
It's not known why the eggs suddenly emerged on the shores of Kivalina last week. Villagers say they've never seen anything like it before.
Samples have been sent for further testing to NOAA's Center for Coastal Environmental Health and Biomolecular Research in Charleston, South Carolina.
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