Commission Decision (EU) 2018/1702Show full title

Biodegradation U.K.

• ‘Inherently biodegradable’ means a substance, which achieves the following level of degradation:

  • > 70 % after 28 days for inherent biodegradation test, or

  • > 20 % but < 60 % after 28 days in tests based on oxygen depletion or carbon dioxide generation.

  Inherent biodegradability shall be measured in accordance with the following tests:

  • Regulation (EC) No 440/2008 (Part C.9 of the Annex), OECD 302 or equivalent methods,

  • tests based on oxygen depletion or carbon dioxide generation: Regulation (EC) No 440/2008 (Part C.4 of the Annex), OECD 306, OECD 310, or equivalent methods.

• ‘Readily biodegradable’ means an arbitrary classification of chemicals which have passed certain specified screening tests for ultimate biodegradability; these tests are so stringent that it is assumed that such compounds will rapidly and completely biodegrade in aquatic environments under aerobic conditions. Substances are considered rapidly degradable in the environment if one of the following criteria holds true:

  1.

  if, in 28-day ready biodegradation studies, at least the following levels of degradation are achieved:

  • tests based on dissolved organic carbon: 70 %,

  • tests based on oxygen depletion or carbon dioxide generation: 60 % of theoretical maximum.

  These levels of biodegradation must be achieved within 10 days of the start of degradation which point is taken as the time when 10 % of the substance has been degraded, unless the substance is identified as an UVCB or as a complex, multi-constituent substance with structurally similar components. In this case, and where there is sufficient justification, the 10-day window condition may be waived and the pass level applied at 28 days; or

  2.

  if, in those cases, where only BOD and COD data are available, when the ratio of BOD5/COD is ≥ 0,5; or

  3.

  if other convincing scientific evidence is available to demonstrate that the substance can be degraded (biotically and/or abiotically) in the aquatic environment to a level > 70 % within a 28-day period.

  Ready biodegradability shall be measured in accordance with the following tests:

  • Regulation (EC) No 440/2008 (Part C.4, C.5 in conjunction with C.6 and C.42 of the Annex), OECD 301, OECD 306, OECD 310, or equivalent methods.

  Note: Within the frame of this criterion, the 10-day window principle will not necessarily apply. If the substance reaches the biodegradation pass level within 28 days but not within the 10-day time-window a slower degradation rate is assumed. U.K.

• ‘Non-biodegradable’ means a substance which fails the criteria for ultimate and inherent biodegradability.

  The applicant may also use read-across data to estimate the biodegradability of a substance. ‘Read-across’ for the assessment of the biodegradability of a substance shall be acceptable if the reference substance differs by only one functional group or fragment from the substance applied in the product. If the reference substance is readily or inherently biodegradable and the functional group has a positive effect on the aerobic biodegradation, then the applied substance may also be regarded as readily or inherently biodegradable. Functional groups or fragments with a positive effect on the biodegradation are: aliphatic and aromatic alcohol [-OH], aliphatic and aromatic acid [-C(= O)-OH], aldehyde [-CHO], Ester [-C(= O)-O-C], amide [-C(= O)–N or -C(= S)–N]. Adequate and reliable documentation of the study on the reference substance should be provided. In case of a comparison with a fragment, not included above, adequate and reliable documentation of the studies should be provided on the positive effect of the functional group on the biodegradation of structurally similar substances.