Ian A. Wright, Amy-Marie Gilpin, & Katherine Warwick, Western Sydney University / The Conversation
The recent air, picturesque vistas, and pristine bush of the Blue Mountains west of Sydney draw millions of visitors a 12 months.
Sadly, the Blue Mountains are additionally the positioning of a controversial investigation into water contamination with “endlessly chemical substances”, additionally referred to as PFAS.
Our recent study investigated long-term PFAS contamination from two incidents, each involving petrol tanker crashes and fires. Each accidents occurred in ingesting water catchments, and our research discovered contamination was current however undetected for twenty-four and 33 years, respectively. We have now searched the worldwide literature and couldn’t discover related examples.
PFAS (Perfluoroalkyl and polyfluoroalkyl substances) are a broad class of 1000’s of artificial chemical substances utilized in quite a few client and trade merchandise. Publicity to PFAS is related to a better threat of a number of sicknesses.
Our analysis reveals how susceptible ingesting water provides are to long-term PFAS contamination. It additionally reveals how contamination can stay hidden because of an absence of PFAS monitoring.
Two historic accidents
The 1992 petrol tanker accident within the Blue Mountains at Medlow Bathtub triggered PFAS contamination of the native ingesting water provide. And 32 years later, it compelled the closure of two storage reservoirs.
Regardless of restricted information, we recognized the supply of contamination as a kind of foaming materials used globally by firefighters to assist extinguish burning gasoline fires. This foaming substance was combined with water utilizing perfluorooctane sulfonate, a kind of PFAS.
Firefighters used this substance to kind a foam “blanket” and coat burning supplies and extinguish liquid fires. The PFAS foams had been used for decades earlier than their dangerous human well being and environmental impacts had been understood.
9 years after the primary petrol tanker accident, one other fuel tanker crash and hearth linked to PFAS contamination occurred in 2000, close to Ourimbah on the NSW Central Coast. The gasoline tanker was carrying 40,000 litres of gasoline, and the crash and hearth had been triggered by a collision with a automotive. This resulted within the tragic demise of two folks.
Just like the Medlow Bathtub accident, information footage confirmed water and foam had been used to manage the blaze. It additionally confirmed a foamy runoff draining from the accident.
Why are PFAS an issue?
PFAS, typically referred to as “endlessly chemical substances”, are a broad class of 1000’s of synthetic chemicals. They’re utilized in numerous products, reminiscent of non-stick cookware, stain-resistant materials, takeaway meals packaging and even cosmetics.
PFAS molecules don’t simply break down and readily accumulate within the tissues of wildlife across the globe. Publicity to small quantities of PFAS sees the chemical substances construct up within the very important organs of animals and people. Analysis of human autopsy tissue revealed accumulation of PFAS within the mind, lungs, liver, kidney, and bones.
In 2025, an Australian Bureau of Statistics report revealed practically all Australians have PFAS chemical substances accumulating in their bodies.
Ought to we be nervous?
Publicity to PFAS is related to a better threat of several illnesses. These embody decreased fertility, increased blood stress, elevated threat of most cancers (significantly prostate, kidney and testicular cancers), liver illness, increased ldl cholesterol, and weight problems.
One of many methods people are more likely to devour PFAS is thru consuming meals containing PFAS and drinking water.
The Higher Blue Mountains water provide serves about 40,000 folks, and is operated by Sydney Water Company. It reported that one of the hazardous types of PFAS, PFOS, reached 16.4 nanograms per litre within the native ingesting water on June 25 2024. That is double the secure quantity, based on the not too long ago revised Australian drinking water guidelines.
Discovery of PFAS triggered the closure of two ingesting water reservoirs downstream of the Medlow Bathtub petrol tanker crash and hearth. Though a scarcity of testing information creates uncertainty, it’s doubtless PFAS contamination was undetected within the Blue Mountains ingesting water provide for greater than 30 years.
What our research confirmed
Our research confirmed contaminated creek water contained 2,000–2,400ng/L of PFOS in October 2025. That is 250–300 instances the utmost secure focus (lower than 8ng/L) really helpful by the Australian Drinking Water Guidelines.
The Blue Mountains contamination plume prolonged downstream into Greaves Creek within the higher Blue Mountains. This creek is a part of the UNESCO Blue Mountains World Heritage Area, the place PFOS ranges exceeded aquatic ecosystem pointers by 100 instances. The secure degree of PFOS focus for defense of freshwater species is 0.23ng/L.
So far as we all know, the PFAS contamination recognized on this research has not acquired any remediation to take away contaminated soil or water. Most PFAS contamination throughout Australia has occurred at websites the place PFAS foam was utilized in repeated firefighting training activities. Our work reveals even single incidents involving PFAS can have long-lasting environmental impacts.
Ian A. Wright, Affiliate Professor in Environmental Science, Western Sydney University; Amy-Marie Gilpin, Senior Lecturer in Invertebrate Ecology, Western Sydney University, and Katherine Warwick, PhD Candidate, Western Sydney University
This text is republished from The Conversation below a Inventive Commons license. Learn the original article.
