REAKTIV-GELB F-68 072 FW

Endpoint summary

Additional information

Environmental Fate

It should be noted that the test substance is not considered as posing a hazard to the aquatic environment.

 

The test substance, Reactive Yellow F-68072 FW, is a solid under all environmental conditions and is highly soluble in water. It has a low volatility (based on a presumed low vapour pressure from the physico-chemical data available) and a low affinity for soil / sediment of log Koc < 1.3. As such, any environmental release will result in virtually all of the substance compartmentalising into water compartments, with little release directly to atmosphere or compartmentalising to soil/sediment compartments.

 

Any potential exposure to the environment is predicted to result in rapid redistribution to water; due to its low volatility, high water solubility and partitioning values indicates that the majority of the substance would eventually partition to water rather than to soil and sediment should it be released to the environment. 

 

A Level III fugacity model was conducted in the US EPA EPISUITE (Mackay,) which assumes steady-state but not equilibrium conditions. The Level III model in EPI Suite predicts partitioning between air, soil, sediment and water using a combination of default parameters and various input parameters. This model has been used to calculate the theoretical distribution of the highest % component substance between four environmental compartments (air, water, soil, sediment) at steady state in a unit world.

 

Partitioning is detailed to be:

-         Air            1.17e-005%

-         Water      1.9%

-         Soil           70 %

-         Sediment 28.1 %

 

It is proposed that although the majority of the substance distributes to the soil and sediment compartments within the model, the high solubility in water indicates that the substance is more likely to distribute to water – e.g. soil pore water. Structural analogues of Reactive Yellow F-68072 FW all showed to be 'not readily biodegradable' under test conditions. In addition, a screening test showed that the test substance is also not inherently biodegradable. By the nature of their design and use, reactive dyes are not intended to be readily biodegradable, as this would assist in the rapid destruction of the dyestuff, rendering it unfit for purpose. As such, it is accepted that such substances are not readily biodegradable under relevant environmental conditions.

As such, the substance is unlikely to achieve a half life of less than 40 or 60 days within fresh water attributed to ready biodegradation alone. However, it is expected to hydrolyse slowly under normal environmental conditions.  Experimental studies on hydrolytic effects demonstrated that the substance does undergo hydrolysis at environmentally relevant pH’s, with a half life of 1.8 days at pH 7 and less than 1 day at pH 9. The dyeing process involves reaction at alkaline pH indicating that it highly unlikely that the substance will be present in waters released to the environment. Should any substance be present, it will rapidly hydrolyse in the environment. As such, abiotic degradation and subsequent removal is anticipated via this route. Studies on direct phototransformation in water are not available but it is assumed on the basis of chemical structure and nature of use that the substance is not degraded by direct photolysis. It is concluded, therefore, that abiotic processes would contribute significantly to the depletion of the substance within the environment. 

 

Reactive Yellow F-68072 FW has a calculated log Pow of -6. This value indicates that possible bioaccumulation in the food chain is not anticipated.  Furthermore, a study of bioaccumulation in aquatic organisms (fish) is available; which gave a BCF value of < 17.9. This experimental data compliments indications from the physico-chemical studies, particularly the fat solubility study (with results of < 0.005 mg in 100 g fat at 37 deg C) indicate that bioaccumulation within body tissues is unlikely. Given the fact that the substance is subject to hydrolysis at biologically relevant pH’s (pH 9), it is anticipated that bioaccumulation of the substance itself would not occur, as hydrolytic effects in association with metabolic effects would result in removal of the substance.

 

Adsorption to soil is deemed to be low, based on the very low soil adsorption coefficient value and high water solubility. Such a low potential indicates that the substance is unlikely to bind tightly to soils and sediments and instead partition almost exclusively to water. As such, significant exposure related effects to sediment and soil dwelling organisms are considered to be negligible.

Based on its high water solubility, low partition coefficient and fairly rapid hydrolysis rate at environmentally relevant pH’s, it can be concluded that it is unlikely that Reactive Yellow F-68072 FW could potentially be persistent within the environment. Abiotic effects within the environment will result in eventual removal and hence significant contact with the organisms in the food chain can considered to be minimised. 

 

Finally, Reactive Yellow F-68072 FW demonstrates low acute toxicity in mammalian studies therefore in the event of exposure to environmental organisms, effects due to secondary poisoning can be excluded.

 

Reliability.

The studies have all been ranked reliability 1 according to the Klimisch et al system. This ranking was deemed appropriate because the studies were all conducted to GLP in compliance with recognised guidelines.

 

Justification for classification or non classification

The above results triggered no classification under the Dangerous Substance Directive (67/548/EEC) and the CLP Regulation (EC No 1272/2008).