Sleeper issue: What are PFAS?

A group of chemicals called PFAS have flown under the radar for years but could be dangerous. Waste Management Review reports on the new national PFAS management plan and its effects on the landfill industry.

Everyday items often contain a number of chemicals, most are harmless or even beneficial, but what happens when these chemicals are found to be a possible threat to human health?

Asbestos was an example of this. It was a popular fireproofing material, and can still be found in houses built before 1990 – before its deadly effects were discovered.

Removing and disposing of these substances and chemicals can be tricky, and if the chemical is already present in the waste stream it makes it even harder to manage.

Chemicals and substances that manage to go undetected cause issues, as often they are widespread and their impacts on health may be unknown.

Per- and poly-fluoroalkyl substances (PFAS) are a group of man-made chemicals that have been heavily used for household and industrial applications since the 1950s. They are found on items like non-stick cookware, fabrics, furniture, carpet stain protectors, food packaging, some industrial processes and in firefighting foams.

Following evidence of their widespread detection in environmental samples, they are considered an emerging contaminant by the global regulatory body, the Stockholm Convention.

Due to their heavy usage, it is still unknown if the most common and well-studied PFAS chemicals, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS) are dangerous to human health, according to the PFAS Health Effects and Exposure Pathways report released by the Australian Government Department of Health.

The report says existing studies on animals have found that PFAS may be linked with issues in the immune system, liver, reproduction, development and benign tumours after prolonged exposure at relatively high levels. However, no existing studies have found a causal link between PFAS exposure and health effects in humans.

Exposure to humans occurs through everyday contact with dust, water and with products containing PFAS. Food consumption tends to be the most common route of exposure as some PFAS can accumulate through the food chain, according to the Australian Health Protection Principal Committee PFAS factsheet.

PFAS are absorbed through the gut but aren’t metabolised or broken down inside the stomach and are slow to be removed from the body.

Due to their chemical structures, PFAS can travel long distances in air and water currents.

The people of Williamtown in NSW were shocked to learn that the nearby Royal Australian Air Force had contaminated the local wetlands with PFAS, according to a release from the NSW Government Department of Health.

The chemicals had slowly worked their way through the soil to the groundwater underneath the site. Surface water samples taken from nearby waterways were found to contain high levels of PFOS, one of the PFAS used in firefighting foams.

To assist organisations and companies cleaning up and handling PFAS, the heads of all state and territory Environment Protection Authorities (EPA), alongside the Federal Government, released a National Environment Management Plan (NEMP).

The plan aims to explain how to properly handle and clean contaminated sites and methods for safely destroying the chemicals. It also has guidelines for what levels indicate the need for action, provides information on what action should occur, techniques for sampling and measuring PFAS concentrations, how to transport and handle the waste and future research to support the plan and any revisions.

Before it was released, there was no consistent guide or direction for communities like Williamtown that had been affected by PFAS contamination.

The standards set within the plan offer guidance, but could be problematic in the short term for those in the industry taken by surprise by PFAS.

EPA Victoria, under direction from the Heads of EPA, organised and ran consultation sessions in capital cities across the country and more than 80 written submissions were collected for the plan.

LANDFILL AND PFAS

PFAS can enter the environment from landfill sites that accept waste containing PFAS through ground and surface water via sewer discharges and leachate movement, the Australian Health Protection Principal Committee report states.

The NEMP outlines how to manage and handle PFAS within landfill. According to the plan, accepting PFAS contaminated materials is a commercial decision for the landfill operator and must be approved by the environmental regulator.

It also says that site by site assessment is needed to determine whether a landfill can accept waste that contains PFAS.

Leachate samples undergoing solid phase extraction for PFAS.

WHAT THE RESEARCH SAYS

Christie Gallen, PhD Candidate at The University of Queensland, has studied the presence of PFAS in Australian landfills to understand which chemicals in the PFAS family are in the Australian solid waste stream, as well as in water treatment plants.

Her research involved testing 35 landfills across Australia which voluntarily participated in a leachate sampling and analysis program.

“We conducted two landfill leachate and waste water treatment sampling campaigns in 2014 in partnership with the Department of the Environment. It was the first time any PFAS analysis had occurred in landfill leachate, and we conducted it on different types of landfills, in terms of their size, age, waste type accepted and geographical location,” Christie says.

“We detected PFAS in every landfill that we tested, in both operational landfills and closed ones. We found that there was a relationship with the age of the landfill and the amount of certain PFAS detected in their leachate.

“Newer landfills had higher concentrations of PFAS in the leachate we studied. There are a number of possible reasons for this. For example, older landfills might have undergone a flushing effect where the PFAS inside them had already been depleted, but it’s hard to tell, as we never know how much PFAS is there to start with.”

Christie says the items where PFAS chemicals were often used may also have an effect on the connection between the age of the landfill and contamination level.

“From the year 2000, PFOS was phased out of use. Before that time, there was a lot more PFOS floating around, mostly on longer use products like carpets or furniture fabrics.

“If someone was to buy a carpet from 1990, they might not replace it for a couple of decades, so even though these chemicals have been phased out of use for years, they would be only entering the waste stream more recently,” Christie says.

“The landfill waste type also seemed to have a relationship with the amount of PFAS. On average, construction and demolition waste landfills had a higher concentration in their leachate.”

“We’re starting to get this simplistic picture where we can expect these PFAS concentrations to be popping up in landfills. But because every landfill is unique, it’s difficult to come up with hard and fast conclusions.”

According to Christie, the problem with PFAS is the fact that they’re naturally persistent and resist breaking down in the environment or the human body. The fact that they are also relatively mobile and persist for a long time in the environment can make clean-up operations difficult and expensive.

“There are some methods developed to remove PFAS chemicals from water and possibly leachate, but still leaves the question of what you do to handle the PFAS once it’s been extracted,” she says.

“By moving it into one place, it does make it more manageable to handle and compartmentalise, but they are still very difficult to destroy. They can be destroyed at high temperatures, but that’s still a challenge as there are not many facilities in Australia that can do that.”

“Destroying PFAS is a very specialised process, which would require a high energy input to dispose of large amounts. That makes it expensive to deal with, and though there are some small experimental methods of disposal, there’s very little employed on a large scale.”

Christie says new detection methods are in progress, with a smartphone app-based portable sensor to detect PFOA that reads a sample based on extract colour, but these methods haven’t been widely adopted yet.

“At the moment, there’s no guideline that dictates a specific type of disposal method for PFAS contaminated leachate that I am aware of,” Christie says.

She says leachate contains a cocktail of other chemicals like flame retardants, metals and pesticides, adding that we’re still just learning the extent of PFAS in landfill leachate.

“First, we need to establish the PFAS profile or fingerprint present in the leachate before we can work out what to do with it.

“Then, you can move to practical questions with what’s the most cost-effective and practical method of remediation, who pays for it and all the things that come along with that,” she says.

THE LOGISTICS OF MANAGING PFAS

Colin Sweet, Chief Executive Officer of Australian Landfill Owners Association (ALOA), says that there is a logistical issue with the new guidelines set in place.

“Nobody has released information on what quantity and what exposure is dangerous to human health. It leaves us in a position where we don’t really know what the criteria are,” Colin says.

“If we look at the report, you can see that the limit for acceptance is seven micrograms per litre in the Australian Standard leaching procedure leachable concentration. How do you test for that with incoming waste?

“Bearing in mind that the biggest landfill in Sydney takes in around 3000 tonnes of waste a day, that’s about 500 truckloads of material. In order to make sure we’re not accepting PFAS contaminated waste, we’d need to take samples from each truck, wait for the test results, and then decide what we want to do with it.”

Colin says because PFAS is so common in household products, it’s difficult to determine what trucks may be carrying contaminated waste.

“If a truck has picked up rubbish from 50 different shops or factories, or if someone has thrown out carpets or furniture, it’s almost impossible to tell without testing. And if the test shows that the load is contaminated, where does it get sent to then?

“Landfills aren’t generating PFAS. It just comes into the facilities and goes out. It appears in the leachate that then needs to be disposed of. In a closed and capped landfill, you’ve also somehow got to manage the leachate that may contain PFAS, even if you’re not taking any more.”

“The topic has just been lumped onto the landfill industry.

“We need to know with respect to what levels of PFAS are in water treatment plants and what can be considered reasonable.”

Landfill operators are given recommendations by the plan on how to properly handle PFAS. The plan says that leachate should be collected in a sump and pumped to a storage location, usually one that is suitably engineered or a lined evaporation pond/tank. If PFAS is detected in high levels, options for treatment and remediation or destruction should be considered and implemented to prevent PFAS distribution to the environment.

Colin says that the current plan’s restrictive guidelines are an issue for leachate management and require practical limits.

“Some landfill owners reinject discharged leachate, while some have to discharge it into sewerage and satisfy the containment treatments. If it’s up to the liquid treatment operators whether they accept PFAS contaminated material, where does the leachate get discharged?”

Colin says he welcomes science-based regulation to ensure PFAS contamination is treated appropriately and says ALOA is establishing its official position on the plan in its current state.

“We support the banning of nonessential PFAS contaminated materials and products and support the regulators in their efforts to try and minimise PFAS in the supply chain.

“We also support the destruction of PFAS through thermal technology, and the implementation of a national standard for landfills,” he says.

Alex Serpo, Policy Officer at the National Waste and Recycling Industry Council, says PFOS is a sleeper issue for landfills across Australia.

“PFOS is analogous to asbestos in terms of its overall national impact, perhaps not as deadly, but it’s a similar kind of problem. It’s longstanding, it’s toxic, it’s difficult to destroy,” Alex says.

“It was used as a fire suppressant – and thus was designed specifically to be difficult to destroy. Currently there are only a few treatment options, one of which is a plasma arc owned by ToxFree, which is an effective way to treat PFOS.”

“Existing stockpiles of PFOS should be identified and treated as the first step in the most environmentally sound manner possible.”

Alex believes that the states should coordinate a response in regard the effects of PFAS in landfills and that clear guidance should be set that takes into consideration infrastructure management and planning across private industry and local governments.

“Infrastructure need a realistic plan, enforceable standards and time to adapt to new regulatory requirements,” Alex says.

Alex says the major issue with PFOS is land contamination. Existing contaminated land issues need to be addressed while landfill standards can come later.

“From a waste management perspective, technology should be used to destroy the existing stores, then an economically and technically realistic plan needs to be put in place for landfill. The industry will need funding, time and government support to apply that correctly.”

Nial Finegan, Chief Executive Officer of EPA Victoria, says PFAS are just one possible pollutant that will require management by any landfill operator.

“EPA will require landfill operators to manage the pollution for which they are responsible and provide management plans to show how they will achieve that and contain PFAS on site as much as possible,” Nial says.

“Under the NEMP, each jurisdiction will be developing further specific advice with respect to landfills licensed to accept PFAS contaminated material.”

Nial says the body of evidence regarding PFAS and their impacts on human health is growing.

“The Commonwealth Government has advised that ‘research has not conclusively demonstrated that PFAS are related to specific illnesses, even under conditions of occupational exposure,” he says.

“It should be noted that as PFAS are highly mobile and persistent in the environment, Environment Protection Authority Victoria takes a cautionary approach about actions to protect human health.

“Table 6 in the NEMP provides a guideline for landfill acceptance criteria which is based on national data, for example the Stockholm Convention, and may be modified by each jurisdiction to reflect specific landfill requirements,” Nial adds.

Nial says landfill operators are responsible for managing the waste they accept.

“How they determine PFAS levels in incoming waste will be one of the challenges they will be required to meet,” he says.

“Appropriately licensed landfill operators will require to test waste loads as per their licence requirements as per current requirements.”

“As per the NEMP, there are multiple alternative management and treatment methodologies available for the management of PFAS contaminated materials.”

Nial says the EPA holds those responsible for creating pollution to account.

“If sites have high PFAS levels they will be expected to demonstrate how they will manage it, that their plan is viable and provide the results that show it is working.”

The Heads of EPA, in collaboration with other groups, will continue to develop the plan and update it by mid-2018, with the first formal review expected five years later. Ecological guideline values and criteria for soil and waste reuse and for water authorities and utilities is expected to be completed by June 2018. The plan will also be supported by guidance notes on the requirements for preliminary treatment and remediation trials, the process for site prioritisation and containment and protocols for data sharing along with a range of other measures.

Research activities to characterise PFAS in trade waste/sewer systems entering wastewater treatment plants will be conducted. This will aim to assist in identifying the relative contributions of industrial sources discharging to trade waste, including landfills, in the total PFAS load.