OCNS ecotoxicology testing
Ecotoxicity data are required for offshore chemical products to
help assess the potential environmental risk in the marine
environment.
The OCNS requires bioaccumulation and biodegradation data, and
aquatic toxicity data from three trophic levels (algae,
crustacea and fish) to predict the potential ecosystem risk and, in turn, rank the
product by Hazard Quotient (HQ).
The registration of a new chemical product will require a full
set of ecotoxicity data on all components (except PLONORs
[Word, 227 KB] and those on the REACH
(EC 1907/2006) Annex IV).
When completing the HOCNF for the mandatory or conditional
toxicity tests, all toxicity fields must be completed. Where a
value was not determined this should be stated on the HOCNF and a
reason given.
Bioaccumulation data must be provided for all
organic substances, with the exception of surfactants. This can be
estimated by measuring Log Pow using the standard OECD
test methods (OECD 107 Shake Flask and OECD 117 HPLC) or
calculating the partitioning of the substances between water and
n-octanol (Pow).
Reliable methods are now available for calculation of Log
Pow for many types of organic substances and often
laboratory testing can be avoided. Calculations should be fully
validated and justified.
BCF data are also relevant. A BCF value can be determined
experimentally in a full bioconcentration test utilising either
fish or a bivalve mollusc (OECD 305 and ASTM E1022).
Biodegradability data must be provided for all
relevant organic substances. For complex mixtures, individual
information for all deliberately added substances is required.
Data from OECD 306, marine BODIS and other acceptable marine
protocols can be submitted. In the absence of valid results for
such tests data from OECD 301A-301F, OECD 310 and freshwater BODIS
may be acceptable.
If the substance is found not to be readily biodegradable, or if
a ready aerobic biodegradation test has not been performed, it will
be assumed that the substance is persistent in aerobic conditions
unless a simulation test (e.g. OECD 308, OECD 309) is performed,
which indicates the opposite.
Aquatic ecotoxicity data
Species requirements:
Algae
- OSPAR recommends test species Skeletonema costatum, or
another suitable algae species if unavailable.
- The test protocol for Skeletonema costatum is ISO/DIS
10253.
- The value that is used should be growth rate EC50,
not the value for biomass.
Crustacea
- OSPAR recommends test species Acartia tonsa, or
another suitable crustacean species if unavailable.
- The test protocol for Acartia tonsa is ISO TC
147/SC5/WG2.
Fish
- OSPAR recommends the test species Scophthalmus maximus
(juveniles); or Cyprinodon variegatus
(juveniles). The recommended test protocol is the PARCOM
Protocol 1995 part B.
- Limit tests are recommended to reduce the numbers of fish used
in testing. Please
see separate guidance.
- If a full fish test is required, the test protocol for the
Scophthalmus maximus test (or other suitable species) -
PARCOM Protocol 1995 Pt B - is recommended.
- Fish-toxicity data may not be required for a component when a
substance's dataset (algae/crustacean toxicity, biodegradation
and/or Log Pow/BCF) indicate that a substitution warning
will be applied, regardless of the fish test result. The supplier
is therefore advised to seek guidance from Cefas before
commissioning tests.
Toxicity-test data for a fish test might reduce the penalty
factor applied by CHARM when only two other species tests are
available and hence reduce the Hazard Quotient (HQ) and banding for
a product. This will only be the case if the individual substance
data "drives" the HQ for the product.
Sediment reworker
Sediment-reworker-ecotoxicity data are not mandatory but are
required in the following circumstances:
Where a component has at
least one of the following conditions a sediment reworker test must
be carried out:
- are "sinkers"; or
- have a Log Pow >4; or
- are in any other way known to adsorb to particles or end up in
the sediment; or
- contain surfactants.
OSPAR recommend test species Corophium volutator, for
which the protocol is PARCOM Protocol 1995 Pt A.
Cefas also actively encourages the use of literature data, where
possible, providing that the data meet certain requirements. Please
see the FAQs on OCNS toxicity-test
data for more information.
Further detail about the test species applicable for the data
submitted can be found in the downloadable document
Criteria for accepting alternative toxicity data to support an
HOCNF application (PDF, 13.9 KB).