Turf wars are currently being played out on sporting fields, schools and in residential landscaping.
The focus is pitching real grass against the artificial variety with many opponents very concerned about the health and environmental impacts of synthetic grasses. Advocates argue that less maintenance and weather readiness make artificial turf attractive.
In March 2024, the NSW Government released draft guidelines (https://www.planning.nsw.gov.au/policy-and-legislation/open-space/synthetic-turf-study) for the use of synthetic turf on playing fields and the public has been invited to submit their feedback by the end of April 2024.
However, many believe the guidelines do not go far enough, citing multiple concerns. Additionally, many countries overseas are taking a tougher line. In particular, the European Union announced last year a ban on a common type of infill used in many artificial grasses.
Opponents of artificial grass surfaces argue that there are numerous associated risks and that there are red flags that should be raising concerns. Issues surround increased microplastic pollution found in water sources near artificial turf fields, the higher potential for injuries at amateur and professional sporting levels, heat and burns caused through its high friction and incredible heat retention (with turfs getting up to 88°C in some cases!) and the loss of biodiversity.
Many Australians are concerned: In a recent response to Sydney’s Inner West Council installing an ‘all-weather’ sporting field planned in 2024, 63% of the 203 email submissions objected to the use of synthetic or hybrid turfs.
In fact, the NSW Government’s Report: ‘Synthetic turf study in public open space’ states: ‘Research has suggested that biological pathogens, toxic chemicals, and micro-plastic ingestion are all risks to human health that are associated with synthetic materials.’
Garnet Brownbill, of the Natural Turf Alliance, is of the opinion that the draft guidelines don’t go far enough and calls for tougher actions: ‘There are unknown human impacts and knowledge gaps (surrounding artificial turf),’ he says. ‘Until we have conclusive evidence that indicates that synthetic fields are safe for humans, and have no long-term degradation on the environment, they should be banned, and installation and implementation should be ceased in Australia.’
The Total Environment Centre and its Australian Microplastic Assessment Project recently called for a five-year moratorium on new planning and approvals for synthetic grass fields, and to subject existing fields to ‘pollution mitigation measures as soon as possible’.
Despite being invented and used in the United States for the first time in the late 1950s and early 1960s, the widespread use of artificial turf is a relatively recent phenomenon in Australia, starting largely in the early 2000s. For professional sporting use cases, it was accepted earlier by lawn bowls and tennis organisations in the 1980s, and later by Cricket Australia, the AFL, and the NRL in 2014.
Artificial turfs are now used in Australian residential settings for landscaping and in commercial settings for recreational and professional use. Ease with maintenance is often cited as a key factor as Australia’s variable rainfall and bright harsh sun can translate to many hours of upkeep for real grass surfaces.
Microplastics: Digging deep into major issues
Artificial turf has three major components: the green blades of artificial grass, a mat beneath the grass to connect all of the blades together, and an ‘infill’ product that sits between the grass blades to give the turf friction.
This infill varies in colour, size, and material. The most common type of infill is called styrene-butadiene rubber crumbs (SBR crumbs, or simply ‘rubber crumbs’). They are minuscule, often recycled shreds of old tyres that are grey-to-black in colour. These crumbs are produced in massive quantities – a typical football field requires approximately 100 tonnes of crumbs (from about 22,000 tyres!). Other types of infill are cork and organic.
Garnet Brownbill says that while the heavy focus on SBR crumbs is justified, it also clouds another issue: that of the blades, which he argues are also problematic. He says that hundreds of kilograms of blades eventually make their way into water supplies and the general environment.
When stripped from a plastic mat, individual blades of artificial grass and SBR crumb infills become ‘microplastics’, tiny fibres, or beads. Microplastics are strictly defined as any piece of plastic that are less than 5mm (or 0.2 inches) in length. They are increasingly entering ecosystems and being consumed by humans and animals.
These blades and crumbs are stripped from their mats in a number of ways. These include being drained out from rainfall, ripped up by children and pets, and regular wear and tear. Carried on clothing and shoes, or carried by small rain streams, a surprising amount of these microplastics enter drainage systems and open water ways. The 2022 NSW Chief Scientist & Engineer ‘Independent review into the design, use and impacts of synthetic turf in public open spaces Final Report’ noted that between “10 to 100kg of infill per year per field” alone is transported away from artificial turf fields in Australia.
When they are consumed by humans or animals after they find their way into food supplies or water sources, they can cause significant issues.
The 2022 NSW Chief Scientist’s report recommended more research into synthetic turf’s impacts and that measures be taken to mitigate environmental risks. It stopped short of suggesting it should be banned. It found that “mixed contaminants including heavy metals” and zinc have been found in SBR crumb. Within aquatic ecosystems, the types that exist in drainage systems and open waterways, ‘sorption’ occurs, where chemicals dissolve into the surrounding water.
In particular, zinc is “considered the toxicant most likely to pose a risk to aquatic ecosystems” and has been found in excess of ‘guideline values for freshwater ecosystems’ within the State.
An example of negative effects was identified in a 2020 study from the Pacific Northwest of the U.S., where coho salmon had ‘unexplained acute mortality’ when migrating to urban creeks to reproduce and coming into contact with stormwater. Through the study, researchers identified a ‘highly toxic quinone transformation product’ of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD) as a cause for the coho salmon’s death - a substance found globally in tyre rubbers used in artificial turfs.
Garnet Brownbill also argues that soil health of nearby natural turf is also heavily impacted by microplastics ‘with implications for microbes and biota’. Referring to aligned biodiversity issues, he says that ‘fields of grass provide opportunities for birds, bees, and other pollinators to forage. This is removed with synthetic grass.’
The potential impacts of artificial turfs also extend to humans. A 2019 study evaluating potential carcinogenicity of synthetic turf crumb rubber https://www.sciencedirect.com/science/article/abs/pii/S0013935118305528 determined that, of the 306 chemicals present, 197 were predicted to be carcinogenic and 19% of the total chemicals were present in quantities harmful for human consumption. Another study published in 2021 that examined 91 crumb rubber infill football field samples from 17 countries and throughout four different continents found hazardous compounds for human consumption – polycyclic aromatic hydrocarbons (PAHs), plasticizers, and vulcanizers – in allsamples.
These chemicals are consumed indirectly by humans, through inhaling evaporated forms of them in surrounding air as determined by a 2014 study, or directly, through oral consumption of microplastics undertaken when swimming in waterways. A small-scale study conducted in this year found that ‘forever chemicals’ called per- and polyfluoroalkyl substances (PFAS) had higher concentrations on coaches’ and students’ hands after using an artificial turf field. These ‘forever chemicals’ aren’t just present in SBR crumb, but also ‘coat artificial turf strands’, as Brownbill points out.
‘Although this was a preliminary study, it raises red flags and calls for additional studies to determine what risk there is of dermal absorption of PFAS from artificial turf,’ Partnership for European Environmental Research (PEER) Science Policy Director Kyla Bennett stated in a press release.
Only mentioned briefly as a challenge in the NSW Chief Scientist’s report, climate change will continue to increase both the frequency and intensity of rain and flooding events in the near future. An unintended consequence of these changes in weather patterns, increased rain and flooding events could accelerate the already high amount of microplastics leaving artificial turf fields each year.
This potential issue is extremely problematic with the NSW Chief Scientist’s report noting that ‘extreme flooding events have moved and lifted entire synthetic turf fields’ in the Central Coast and Sydney floods of February-March 2022, and trends occurring for more intense rainfall periods.
Where is the grass greener?
Regardless of the research indicating highly concerning health and environmental impacts, many Australian councils, schools, sporting organisations and homeowners press ahead and opt for artificial grass. Their rationale is lower maintenance ‘costs’ and ‘ease’ of use.
A number of mitigations and alternatives have been suggested.
One solution that was implemented in the European Union on September the 25th of 2023 was a ban on SBR crumb being used as infill.Instead, other more environmentally conscious materials such as cork and coconut husk are used throughout the EU to give artificial fields the friction they require.
Cities like Boston in the U.S., and countries like in the Netherlands are aiming or have already banned artificially turfed surfaces in some or all situations.
Some artificial turf fields across New South Wales install fences, pipes and gates surrounding artificial turf fields that intend to keep potential microplastics from leaving fields. Mats for users of fields to rub their shoes clean from microplastics placed at entrances and exits of fields are recommended to minimise the effects fields have on surrounding environments.
Garnet Brownbill advocates implementing natural turfs with ‘holistic turf management practices’ involving drainage, irrigation, and run-off management practices. Says Brownbill: ‘We should be doing the same thing as farming practices (with natural turfs instead) – rotating areas that are practised on, and simple things like aerating the fields 3 to 4 times a season, and providing water and nutrients’.
As recommended in the NSW Chief Scientist Report, ‘advancing materials’ research into new alternative materials’ and collaboration in ‘government and non-government settings and sectors’ is needed to ‘develop appropriate standards and end of life solutions’ – but these recommendations don’t highlight any urgency for action.
The issue is certainly not a level playing field.
Author: Gautam Mishra