Reaction products of diazotized 2-amino-4-nitrophenol, coupled with resorcinol and subsequently coupled with diazotized 5-amino-4-hydroxynaphthalene-2,7-disulfonic acid and diazotiazed paranitroaniline

Endpoint summary

Additional information

The aquatic toxicity assessment and classification are based mainly on the short-term toxicity information on Acid Brown 349 and on the similar substance 1.

 

According to the CLP Regulation (EC 1272/2008), acute aquatic toxicity is normally determined using a fish 96-hour LC50 , a crustacean species 48-hour EC50 and/or an algal species 72- or 96-hour EC50; nevertheless it is also specified in the Regulation that data on other species (e.g. Lemna spp.) shall also be considered if the test methodology is suitable. These species cover a range of trophic levels and are considered as surrogate for all aquatic organisms.

 

Data are available for Daphnia magna (EC50 48h Daphnia magna = 100 mg/L), on similar substance 1 and for Lemna minor (ErC50= 100 -1000 mg/l) on Acid Brown 349.

 

Several studies on algae conducted on dark dyes, including those with a modified test system for dye-stuffs, showed that the growth inhibition is mainly correlated to the reduced light absorption, caused by the stained water and not due to an effective toxicity of the dye.

Therefore, test on Acid Brown 349 on the aquatic plant "Lemna minor", was conducted and it demonstrated that no acute toxicity is expected as not influenced by the shading effect

 

Lemna is an aquatic plant that develops his leaves on the surface of the water, while nourishing substances are taken from the water solution. With this test the observed effect is only related to the potential toxicity of the substance and not to the potential shading effect of an Alga study. A deviation to the protocol has been applied to the test recommended for dyes (Michael Cleuvers, 2002), i.e. beakers will be incubated on a black non-reflecting surface; additionally, the walls of the incubation chambers will also be covered with black fabric in order to avoid reflection.

According to a broad agreement by EU Competent Authorities the Lemna test is a suitable alternative to an algal test for strongly coloured substances, as mentioned in the introduction to the method C.26 “Lemna sp. Growth inhibition test” of the European Commission Regulation No 761/2009 of 23 July 2009. "This method is equivalent to OECD TG 221 (2006). The EU authorities’ agreement refers to the Manual of Decision (EU Manual of Decisions dated July 2006, athttp://tsar.jrc.ec.europa.eu/documents/Manual_of_decisions.pdf13.5.3 Alternatives to the algae growth inhibition test with coloured substances). This method is also in conformity with the content of the Guidance on information requirements and chemical safety assessment — Chapter R.7b: Endpoint specific guidance; Table 7.8.3 Summary of difficult substance testing issues, available at:

https://echa.europa.eu/documents/10162/13632/information_requirements_r7b_en.pdf, as indicated in the Guidance on the Application of the CLP Criteria v 4.0, section 4.1.3.2.2.

Commission Directive 2001/59/EC of 6 August 2001 adapting to technical progress for the 28th time Council Directive 67/548/EEC on the approximation of the laws, Regulations and administrative provisions relating to the classification, packaging and labelling of dangerous substances, paragraph 5.2.1.3., that   “where it can be demonstrated in the case of highly coloured substances that algal growth is inhibited solely as a result of a reduction in light intensity, then the 72h EC50 for algae should not be used as a basis for classification. ”http://ec.europa.eu/environment/archives/dansub/pdfs/annex6_en.pdf.

For highly light absorbing substances, the modified standard algae growth inhibition test is not recommended. With these particular substances, a modified standard Lemna-test (OECD TG 221) is recommended.

 

Therfore, according to the CLP Regulation (EC 12720/2008) criteria for the identification of the classification categories for hazardous to the aquatic environment, studies about short-term toxicity to fish, Daphnia Magna and the Lemna study , Acid Brown 349 is not classified.