'Alarming' find in Aussie dolphins sparks water quality concerns

While the high PFAS levels have now been documented, no one knows how they reached such high levels in the dolphins' livers.

Tests on dolphins living in Australian waters have revealed many are riddled with toxic chemicals, similar to those found in household "non-stick" products.

After examining the liver of a juvenile male from Victoria’s iconic Port Phillip Bay, researchers discovered it had the highest level of PFAS ever recorded in a dolphin. These toxins are commonly referred to as “forever chemicals” because some scientists believe they don’t break down in our bodies or the environment.

The dolphin study results have been revealed amid growing calls to ban the sale of the chemicals in Australia, and the government indicating it plans some restrictions on imports.

A dolphin swimming in Port Phillip Bay with Melbourne's skyscrapers in the distance.
Melbourne's dolphins have been found contaminated with alarming levels of PFAS. Source: Marine Mammal Foundation

Despite the staggeringly high presence of PFAS in the dolphin, you might be surprised to learn they’re not actually manufactured in Australia. However, they are imported into the country.

These chemicals are a common component in many products like non-stick cookware, sunscreens, cosmetics and stain resistant sprays. They’ve also been incorporated into firefighting foams, packaging and possibly even toilet paper.

Key PFAS facts you need to know

  • PFAS are Perfluoroalkyl and Polyfluoroalkyl synthetic chemicals designed to make substances non-stick.

  • If you live in Australia, you most likely have detectable levels of PFAS in your blood.

  • Chronic exposure in animals has been linked to several concerning health issues.

  • While Australian authorities maintain the impact on humans is yet to be "well established", the US warns PFAS could lead to increased cancer risk, low birth weight, high cholesterol and liver enzyme changes.

What the dolphin results can tell us about Victoria's waters

The juvenile male had 30 per cent more PFAS in its liver than any other global sample, but it wasn’t just this result that led researchers to describe the situation as "alarming". Tests of 38 dolphin carcasses collected in Port Phillip Bay and the Gippsland Lakes found PFAS levels were consistently high. The study’s lead author, RMIT researcher associate Chantal Foord, described this as “highly concerning and globally significant”.

While it had long been established that water across the dolphins’ Victorian habitats was polluted, the new results reveal for the first time the concentrations that exist in dolphin bodies.

Left - an egg on a non-stick frying pan. Right - someone sunbaking.
PFAS are regularly found in non-stick frying pans and sunscreen. Source: Getty (File)

Foord chose to study dolphins because they are at the top of the food chain, so they are absorbing PFAS from the rest of the food chain. “They’re a canary in the coal mine, because they tell us what’s in the water system… and they could be an indicator that there’s a potential concern about high chemical concentrations,” she said.

But she doesn’t think the high concentrations found in dolphins would necessarily be the same in humans. “Dolphins eat the entire animal, the liver, kidney, everything, but we’re only eating the muscle tissue and concentrations are nowhere near as high,” she said.

Foord warns her research raises a “lot of questions” as researchers are yet to understand where the pollutants are originating from. But unfortunately, we’re unlikely to know the source any time soon because Foord's research has concluded and there is no more funding immediately available.

Rare dolphin population under threat

The research was a joint project between RMIT, Marine Mammal Foundation and Melbourne University, and looked at four types of dolphin, including the Burrunan species, an animal recognised as distinct by the state of Victoria.

First described in 2011 by Dr Kate Robb who heads the Marine Mammal Foundation, Burrunan dolphins are restricted to Southern and South Eastern Australia, the Victoria population is believed to number just 250 individuals.

“These are incredibly small populations and they’re living near industrial, agricultural and urban areas, they are particularly susceptible,” Robb told Yahoo. “A lot of our focus has been based on the threatening processes that increase the risk of extinction.”

While PFAS is a concern for Burrunan dolphins, they are likely just one of several threats to the species. While the Port Phillip Bay population is believed to be stable, the Gippsland Lakes residents have declined 60 per cent in recent years. Two factors that have likely impacted water quality are the Black Summer Bushfires and the La Niña weather system.

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