Biodegradable infill at risk

The Risk Assessment Committee (RAC) of the European Chemical Agency (ECHA) has decided to further investigate ‘biodegradable’ polymers as part of their investigation for the restriction dossier on intentionally added microplastics. ECHA is considering a ban on polymeric infills like SBR, TPE and EPDM amongst others, as polymeric infill particles contribute to environmental pollution from microplastics. While biodegradable infills will ultimately vanish, RAC is not convinced that these infills will not leave a polluting residue.

The European Commission aims for reducing microplastics pollution by 400.000 tonnes in the coming 20 years. As third generation synthetic turf fields require a vast amount of (polymeric) infill, banning this infill would allow the commission to take a giant leap. Until recently biodegradable infills were not included in the proposed ban, but the views of RAC have changed.

According to RAC, test material can be considered to be (bio)degradable, and therefore derogated from the restriction, if it meets one or more of the ‘screening-tier’ criteria described under elements 1-4, below. If the test material does not meet any of the criteria described under elements 1-4, further ‘higher-tier’ assessment (5) can be conducted to demonstrate (bio)degradability under relevant environmental conditions.

  1. Ready biodegradation -60 % mineralisation measured as evolved CO2or consumed O2in 28 days (10-day window does not apply). Permitted test methods: OECD TG 301 B,C,D,F and OECD TG 310.
  2. Enhanced/modified ready biodegradation -Test duration may be extended to up to 60 days and larger test vessels used. 60 % mineralisation measured as evolved CO2or consumed O2in 60 days (10-day window does not apply). Permitted test methods: OECD TG 301 B,C,D,F, OECD TG 310, and modified OECD TG 306 (mineralisation measured as evolved CO2)
  3. Inherent biodegradation ≥ 70 % mineralisation (measured as O2uptake or evolved CO2) fulfilling the TG specific criteria as indicated below. Permitted test methods: . OECD 302B (Zahn-Wellens), ≥70 % mineralisation within 7 d, log phase no longer than 3d, removal before degradation occurs below 15%, pre-adapted inoculum is not allowed
  4. Bio(degradation) relative to a reference material; Ultimate degradation of ≥ 90 % relative to the degradation of the reference material within 6 months in aquatic test, and 24 months in soil and water/sediment interface tests.

Especially the latter will be difficult to accept as no field owner would want to see its infill disappear naturally with 6 to 24 months.

RAC’s proposal for further investigation will be submitted to the European Commission for review later this year.

 

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