PFCs are of increasing interest in Australia and have been detected at a number of locations nationally and internationally especially where fire fighting facilities were located.
PFC testing is now well established in Australia (NATA accredited methods from June 2009) and detection limits are extremely low. With increasing interest in these chemicals the question has often been asked – where do they end up and where do you find them? Many studies have been carried out internationally and the presence of Bisphenol-A and DEET have long been identified as common in leachates among many landfills. In more recent time, PFCs have been detected in landfill leachates. This is of interest due to their inclusion in the Stockholm Convention and also their physical properties and mobility.
With a number of overseas papers reporting the presence of PFCs in landfill leachates and the question often raised as to ‘what makes up the organics or TOC in my landfill leachates,’ ALS commenced a small study in Australia. This involved determining whether PFCs were present in a random selection of landfill leachate, aeration pond and evaporation pond samples. Fifteen leachate type samples were tested from small and large metropolitan landfills across three states. A very small survey of groundwater samples was also performed.
PFCs in landfill leachates plus aeration/evaporation ponds
- PFCs were detected in all landfill leachates/evaporation/aeration pond samples with PFOS or PFOA found in every sample tested.
- PFOS was detected at up to 1.87ug/L with two results over 1ug/L in leachates/evaporation/ aeration pond samples.
- PFOA was detected at up to 0.88ug/L with six samples returning results over 0.5ug/L
- 6:2 FTS and 8:2 FTS were detected in 10 of 15 samples tested and at levels up to 13.0ug/L with several results over 10ug/L
- Other PFCs were detected at up to 4.6ug/L with PFBS, PFHxS, PFHxA, PFHpA, PFOSA and PFNA the most prevalent.
This data demonstrated that PFCs are present in landfill leachates in Australia as identified overseas and that appropriate controls may be warranted. Please see figure 1 overleaf for the profile of leaches detected and figure 2 with analytical LORs, median results of positive detects and CAS numbers.