1-[bis[4-(diethylamino)phenyl]methyl]naphthalene-2,7-disulphonic acid

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Additional information

Acid Green 016 has been included by ECHA into the Annex III inventory; one of the critical aspects indicated as reason for inclusion is that the substance is suspected to be potentially toxic for reproduction: the Toolbox profiler DART scheme v.1.0 gives an alert for toxicity to reproduction.

In particular, DART refers to triarylmethane dye, as known precedent reproductive and developmental toxic potential.

The triarylmethane dyes are synthetic organic compounds containing triphenylmethane backbones; the scaffold structure of Acid Green 016 is characterized by two phenyl rings and a naphthalene sulphonate group. The differences occurring in the backbone structure may significantly impact the substance bioavailability and the toxicological behaviour. In particular, the major degree of sulphonation leads to expectation that the substance would be excreted quickly and easily, in fact the introduction of a sulphate function often decreases bioavailability and toxicity to mammals (Worth and Tier, 2007).

Unfortunately, there are no available data on Acid Green 016 reproductive toxicity, thus information on the structural analogous Green S (E 142) (EC: 221-409-2; CAS: 3087-16-9) have been taken into account.

Green S (E 142) is a triarylmethane food colour consisting of dark-green powder or granules, soluble in water and slightly soluble in ethanol.

Green S is authorised as a food additive in the EU; on 2010 the Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion re-evaluating the safety of Green S (E 142) (EFSA, 2010).

The available studies showed that the reproductive performance was not affected by Green S. There were no consistent treatment-related differences in the number of implantations, the number of implantations resulting in viable fetuses or in the weight and appearances of the fetuses and sex ratio. A NOAEL of 500 mg/kg bw/day has been indicated.

READ ACROSS APPROACH

The target chemical Acid Green 016 and the structural analogous Green S share the same scaffold structure, characterized by two aniline rings and a naphthalene sulphonate moiety. One of the differences is that anilines bear methyl groups in case of Green S, instead of the ethyl ones; this is expected to not determine a different reactivity and the steric indance for the target substance.

A further difference regards the presence of a hydroxy group on the naphthalene sulphonate portion of Green S. From the metabolic point of view, the two substances involved in read across approach represent subsequent oxidative steps, i.e. Green S can be considered as a possible oxidative product of Acid Green 016 and this lets to expect a comparable adsorption, distribution and excration pathway.

The last difference between similar substance and target chemical concerns the salification, which is expected to not impact the reliability and suitability of the read across approach proposed; in fact, a salification of Acid Green 016, due to biological processes, is likely to occur.

REFERENCE

EFSA (2010). EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS); Scientific Opinion on the reevaluation of Green S (E 142) as a food additive. EFSA Journal 2010;8(11):1851. [32 pp.]. doi:10.2903/j.efsa.2010.1851. Available online: www.efsa.europa.eu

Worth, A. and G. Tier (2007), A Compendium of Case Studies that helped to shape the REACH Guidance on Chemical Categories and Read Across, EUR report no 22481 EN.Worth A & Patlewicz G (Eds).

Effects on developmental toxicity

Additional information

Acid Green 016 has been included by ECHA into the Annex III inventory; one of the critical aspects indicated as reason for inclusion is that the substance is suspected to be potentially toxic for reproduction: the Toolbox profiler DART scheme v.1.0 gives an alert for toxicity to reproduction.

In particular, DART refers to triarylmethane dye, as known precedent reproductive and developmental toxic potential.

The triarylmethane dyes are synthetic organic compounds containing triphenylmethane backbones; the scaffold structure of Acid Green 016 is characterized by two phenyl rings and a naphthalene sulphonate group. The differences occurring in the backbone structure may significantly impact the substance bioavailability and the toxicological behaviour. In particular, the major degree of sulphonation leads to expectation that the substance would be excreted quickly and easily, in fact the introduction of a sulphate function often decreases bioavailability and toxicity to mammals (Worth and Tier, 2007).

Unfortunately, there are no available data on Acid Green 016 reproductive toxicity, thus information on the structural analogous Green S (E 142) (EC: 221 -409 -2; CAS: 3087 -16 -9) have been taken into account.

Green S (E 142) is a triarylmethane food colour consisting of dark-green powder or granules, soluble in water and slightly soluble in ethanol.

Green S is authorised as a food additive in the EU; on 2010 the Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion re-evaluating the safety of Green S (E 142) (EFSA, 2010).

In the multigeneration study in rat, the Panel derived a NOAEL of 500 mg/kg bw/day, based on increased spleen and kidney weight, taking into account that no effect on reproduction and offspring development were recorded. During the developmental study accelerated ossification of phalanges was reported at the hishest tested dose; however, this effect was not seen in other parts of the skeleton, therefore it was not considered as an adverse effect. The Panel concluded that the NOAEL is 1000 mg/kg bw/day for fetal development.

READ ACROSS APPROACH

The target chemical Acid Green 016 and the structural analogous Green S share the same scaffold structure, characterized by two aniline rings and a naphthalene sulphonate moiety. One of the differences is that anilines bear methyl groups in case of Green S, instead of the ethyl ones; this is expected to not determine a different reactivity and the steric indance for the target substance.

A further difference regards the presence of a hydroxy group on the naphthalene sulphonate portion of Green S.From the metabolic point of view, the two substances involved in read across approach represent subsequent oxidative steps, i.e. Green S can be considered as a possible oxidative product of Acid Green 016 and this lets to expect a comparable adsorption, distribution and excration pathway.

The last difference between similar substance and target chemical concerns the salification, which is expected to not impact the reliability and suitability of the read across approach proposed; in fact, a salification of Acid Green 016, due to biological processes, is likely to occur.

REFERENCE

EFSA (2010). EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS); Scientific Opinion on the reevaluation of Green S (E 142) as a food additive. EFSA Journal 2010;8(11):1851. [32 pp.]. doi:10.2903/j.efsa.2010.1851. Available online: www.efsa.europa.eu

Worth, A. and G. Tier (2007), A Compendium of Case Studies that helped to shape the REACH Guidance on Chemical Categories and Read Across, EUR report no 22481 EN.Worth A & Patlewicz G (Eds).