{
  "url": "https://openlegislation.uk/eu-regulation-2009-761/annex-V/appendix-1",
  "json_url": "https://openlegislation.uk/eu-regulation-2009-761/annex-V/appendix-1.json",
  "legislation": "eur/2009/761",
  "legislation_title": "Commission Regulation (EC) No 761/2009 of 23 July 2009 amending, for the purpose of its adaptation to technical progress, Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) (Text with EEA relevance)",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2009-761",
  "path": "annex/V/appendix/1",
  "kind": "appendix",
  "number": "1",
  "heading": "Phase distribution of 14C",
  "text": "In order to check the procedure, the routine measurements of residual total organic 14C activity (TOA) should be supplemented by mass balance measurements involving a direct determination of the evolved 14CO2 after trapping in an absorber (see Appendix 3). In itself, a positive 14CO2 formation is a direct evidence of biodegradation as opposed to abiotic degradation or other loss mechanisms, such as volatilisation and sorption. Additional useful information characterising the biodegradability behaviour can be obtained from measurements of the distribution of TOA between the dissolved state (dissolved organic 14C activity, DOA) and the particulate state (particulate organic 14C activity, POA) after separation of particulate by membrane filtration or centrifugation. POA consists of test substance sorbed onto the microbial biomass and onto other particles in addition to the test substance carbon that has been used for synthesis of new cellular material and thereby incorporated into the particulate biomass fraction. The formation of dissolved 14C organic material can be estimated as the DOA at the end of biodegradation (plateau on the degradation versus time curve).\nEstimate the phase distribution of residual 14C in selected samples by filtering samples on a 0,22 μm or 0,45 μm membrane filter of a material that does not adsorb significant amounts of the test substance (polycarbonate filters may be suitable). If sorption of test substance onto the filter is too large to be ignored (to be checked prior to the experiment) high-speed centrifugation (2 000 g; 10 min.) can be used instead of filtration.\nProceed with the filtrate or centrifugate as described in Appendix 3 for unfiltered samples. Dissolve membrane filters in a suitable scintillation fluid and count as usually, normally using only the external standard ratio method to correct for quenching, or use a sample oxidiser. If centrifugation has been used, re-suspend the pellet formed of the particulate fraction in 1-2 ml of distilled water and transfer to a scintillation vial. Wash subsequently twice with 1 ml distilled water and transfer the washing water to the vial. If necessary, the suspension can be embedded in a gel for liquid scintillation counting.",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2009/761/annex/V/appendix/1",
    "retrieved_at": "2026-11-01T14:51:19.625001+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}