Hydrogen [tris[[[3-[(2-ethylhexyl)oxy]propyl]amino]sulphonyl]-29H,31H-phthalocyaninesulphonato(3-)-N29,N30,N31,N32]cuprate(1-), compound with 3-[(2-ethylhexyl)oxy]propylamine (1:1)

Endpoint summary

Description of key information

The UVCB substance consists of high molecular weight components of very poor solubility in water, but good solubility in octanol. Based on the n-octanol/water partition coeffiencent, a potential for accumulation might in theory  be possible. However, absence of systemic effects and absence of indications for substance such as test-item related coloration of internal organs or urine were observed for a structural analogue with slighthly smaller substitutents. Therefore, there is no indication of bioaccumulation.

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

Solvent Blue 70 consists of several blue colored isomers which are mixed sulfonated copper phthalocyanine amines or sulfonamides (see structures in the attached document). The molecular weight range is 814 -1591. The highest molecular weight of 1571 g/mol belongs to the component with four sulfonamide residues at the copper phthalocyanine core.

 

Target und main analogue (Solvent Blue 67) are identical in their core structure and their degree of substitution. They differ in the chain length of the branched side chain of the amine cation. In the target, it is3-((2-ethylhexyl)oxy)-1-propanamine whereas in the main analogue, it is the smaller 3-((1-methylethyl)oxy)-1-propanamine.Consistent with the longer alkyl-chain, the target substance is of better solubility in octanol. Both are poorly soluble in water and the solubility of the target substance is assumed to be slightly lower, noting that this was not verified experimentally as the water solubility was below the limit of detection.

 

Most components have a molecular weight of greater than 1000 g/mol which is a generally accepted threshold for systemic uptake. As the solubility in water is very low, transport in aqueous systems is very poor. The solubility in octanol is very high (136g/L), so solubility in fat is also expected to be good. However, experience with lower molecular weight solvent dyes shows that systemic uptake can be visualized at necropsy via coloring of the tissues or during the study via coloration of urine. In this case, no bluish discoloration of any organ or fat tissue was observed at the end of the OECD 422 study (BASF 2013) for the slightly smaller analogue SB 67 or in acute studies with the substance itself.Note here that for the highly soluble disodium salt of di-sulfo copper phthalocyanine, subacute oral dosing with 1000 mg/kg bw turned the urine colour in (blue plus yellow equals) green.

The main analogue is on average smaller in molecular weight and less hydrophobic than the target substance. It is therefore regarded as worst case in regard to potential systemic uptake compared to the analogue. It is stressed that for both target and main analogue, size and water solubility are in a range where absence of systemic uptake is plausible. At the same time, the solubility in octanol – though higher for the target, is still very high for the main analogue. Therefore, any uptake related to octanol solubility would have been already observed for the main analogue.

 

The copper phthalocyanine core itself has been investigated as part of the US national toxicology program. It was found to be not systemically available upon ingestion.Concentrations of copper phthalocyanine were analyzed in liver and kidney of male rats and mice after oral exposure in a subchronic 90-day feeding study. The concentrations were 0.3 %, 0.6 %, 1.25 %, 2.5 % and 5 % in the diet for rats (corresponding to approx. 0, 250, 500, 1100, 2200 and 4500 mg/kg bw for both sexes [based on 16.4 g/d average food consumption, 0.182 kg average bw for males and on 11.55 g/d average food consumption, 0.130 kg average bw] for females) and mice (approx. 0, 1000, 2000, 4000, 8000 and 16000 mg/kg bw for males [based on 7.3 g/d average food consumption, 0.023 kg average bw] and approx. 0, 1100, 2200, 4700, 9400 and 18700 mg/kg bw for females [based on 7.1 g/d average food consumption, 0.019 kg average bw], respectively), administered on 90 consecutive days. The liver and kidney tissues from the highest dose and from controls of male animals were dissolved in nitric acid and subsequently analyzed for copper by atomic absorption spectrophotometry. No statistically significant increases of copper incorporation were reported in the liver (2.82 ppm +- 0.34 ppm vs. 2.78 ppm +- 0.51 ppm) and kidney (5.62 ppm +- 0.49 ppm vs. 5.30 ppm +- 0.83 ppm) tissues of treated male rats of the highest dose group, compared to control animals. Therefore, the authors strongly suggested that the test material was not absorbed under the test conditions chosen. Slight, but statistically significant increases of copper incorporation were reported in the liver (3.98 ppm +- 1.16 ppm vs. 3.0 ppm +- 0.34 ppm) and kidney (7.47 ppm +- 2.86 ppm vs. 4.66 ppm +- 0.6 ppm) tissues of treated male mice, compared to control animals (Batelle 76-34-106002).

No experimental data is available for the dermal route of exposure. A default skin permeability of 10% can be assumed according to ECHA guidance if the molecular weight is higher than 500 g/mol and the log Pow is higher than 4. These criteria are fulfilled. Considering the molecular weight of > 1000 g/mol and the very poor solubility in water, skin permeability is considered to be negligible.

No experimental data is available for the inhalation route. It is not volatile and exposure could only occur via dusty material. Existing national exposure limits for dust ensure sufficient protection against dust-related effects. ECHA guidance proposes a limit of 10 mg/m³air.