Leucophor 1111X

Toxicity to terrestrial plants

Description of key information

waiving

Additional information

According to the REACH Regulation EC 1907/2006, Annex IX, Column 2 (specific rules for adaptation from Column 1), plant toxicity testing is not proposed by the registrant because the Chemical Safety Assessment, according to Annex I, does not indicate the need to investigate further the effects on plants.

Leucophor 1111X is a Stilbene Fluorescent Whitening Agent (SFWA), 4,4’-bis(1,3,5-triazinyl-2-yl)amino)stilbene-2,2’-disulfonic acid (DAS) derivative. This class of substances have been available since 1941 and remain the most important class of optical brighteners in terms of quantity [1]. Some 75 derivatives Because fluorescent whiteners have been found to be present in ppm amounts in composted sludge of waste water treatment stations, investigations have been conducted in order to assess whether SFWAs were taken up through the root system by higher forms of plant life and whether should the sludge be used for land fill. In literature secondary source [3], it is reported that Muecke et al. [4] have investigated this and have found evidence of a successive accumulation of radiolabelled substances on the roots of bean plants (Phasaeolus vulgaris). Plants grown for 40 days in a nutrient solution containing 11.5 ppm of labelled SFWAs analogous substance 04 and 08 showed on their roots a linear increase in the accumulation of the whiteners applied. The authors also show that this accumulation of the whitener on the roots is greatly reduced if the plants are grown in soil instead of nutrient solution. Due to the strong adhesion of the SFWA to the soil particles, only 2 % of the amount of whitener applied to the soil was found on the roots after 42 days. The same writers also showed that the growth of the test plants was not adversely affected by the application of the analogous substance 04 in amounts far in excess of those used commercially.

Ganz et al. [3 and 5] have conducted similar experiments using corn plants (Zea mais) and soybean plants (Glycine scja) and analogous substance 04 in concentrations of 1, 10, 100, and 1000 ppm of the weight of the soil. ln the experiment with 1000 ppm analogous substance 04 they detected in the plants radioactivity corresponding to 0.4 ppm of the substance or less in the case of soybeans and only 0.07 ppm or less in com plants. In the experiments with the lower concentrations no radioactivity was detectable in the plants.

The substances abovementioned and used in a read across approach are Stilbene derivatives Fluorescent Whitening Agents salts. They display similar structural and physicochemical properties: all of them exhibit high degree of dissociation in water and very low octanol/water partition coefficients because to a higher affinity with water phase than the octanol one. They are all very soluble in water, due to the presence of sulphonated groups in the molecules; all of them are non readily biodegradable and are expected to undergo to the same environmental fate.

In both cases the read across approach can be considered as reliable and representative.

Further details about the justification for read across approach are given in the report attached to the Section 13 of this dossier.

REFERENCE

[1] AAVV, 2003. Industrial dyes. Chemistry, Properties, Applications. Edited by Klaus Hunger. Wiley-vch.

[2] Siegrist A. E., Eckhardt C., Kaschig J., Schmidt E, 1991. Optical Brighteners in Ullmann’s Encyclopedia of Industrial Chemistry, vol. A18, VCH, Weinheim, pp. 153176.

[3] Zinkernagel R., 1975. Fluorescent whitening agents in the environment. Environ Qual Saf Suppl. 4:12.-42.

[4] Muecke W., Dupuis G., Esser H.O. 1975. Fluorescent Whitening Agents, Environmental Quality and Safety, Supplement Vol. IV. Ed. by F. Coulston and F. Korte, p. 174, Georg Thieme Verlag, Stuttgart and Accademic Press, New York/London.

[5] Ganz C.R., Lyman F.L., Schulze J., Stensby P.S., 1975. Macek:Environ. Sc. Technol. 9: 738 - 744.