Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
no hazard identified

Marine water

Hazard assessment conclusion:
no hazard identified

STP

Hazard assessment conclusion:
no hazard identified

Sediment (freshwater)

Hazard assessment conclusion:
no hazard identified

Sediment (marine water)

Hazard assessment conclusion:
no hazard identified

Hazard for air

Air

Hazard assessment conclusion:
no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
no hazard identified

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential to cause toxic effects if accumulated (in higher organisms) via the food chain

Additional information

Conclusion on classification

The CLP Regulation (EC No 1272/2008) states that Aquatic Chronic 4 is applicable to substances in:

 

Cases when data do not allow classification under the above criteria but there are nevertheless some grounds for concern. This includes, for example, poorly soluble substances for which no acute toxicity is recorded at levels up to the water solubility (note 3), and which are not rapidly degradable and have an experimentally determined BCF≥500 (or, if absent, a log Kow≥4), indicating a potential to bioaccumulate, will be classified in this category unless other scientific evidence exists showing classification to be unnecessary. Such evidence includes chronic toxicity NOECs > water solubility or > 1 mg/l, or evidence of rapid degradation in the environment.

The substance fulfills this criteria in that no scientific data apart from QSAR exists to dispute the bioaccumulation potential assigned to the substance. As such, the registrant proposes appropriate classification which is as follows:

CLP Regulation (EC No 1272/2008): Aquatic Chronic 4; H413: May cause long lasting harmful effects to aquatic life.

 

The environmental studies conducted on the substance have all been ranked reliability 1 according to the Klimish et al system. This ranking was deemed appropriate because the studies were conducted to GLP and in compliance with agreed protocols. Sufficient dose ranges and numbers are detailed; hence it is appropriate for use based on reliability and animal welfare grounds.

 

General discussion

There are no effects at the limit of solubility in either the aquatic toxicity studies, or in the chronic toxicity test in Daphnia, as limit values are derived for both NOEC and EC50 values. It is well understood that if no toxicity value exists for a substance, then it is impossible to derive a PNEC for a risk assessment. Furthermore, even if a substance is found to be nontoxic in an acute test at its limit of solubility, it cannot be assumed that toxic effects will not occur at lower concentrations over a chronic exposure period. ECHA Guidance document CHAPTER R.7B – ENDPOINT SPECIFIC GUIDANCE Pg 80 discusses advice on substance is poorly soluble in the test medium (water solubility typically <1 mg/L). The advice given here is “Substances that are not chronically toxic to aquatic organisms at their limit of solubility rarely need further consideration.” Furthermore, it is not possible to use a default assessment of 1/100th of the water solubility value, as the water solubility of the substance is deemed to be < 0.0067 mg/l at 20 °C.

Therefore, it is considered that the substance poses no hazards to the environment at the limit of solubility in water. It is proposed that a further investigation of chronic toxicity to fish is not undertaken; this species is not anticipated to be sensitive to the substance, as there are no indications of this in the acute studies, and a further animal study is not required to refine the risk which can be adequately predicted. The substance is demonstrated to be not harmful to aquatic organisms at the limit of solubility in water in both acute and chronic studies. Therefore whilst classification is provided as a "safety net" classification, is it the registrants consideration that the substance is not hazardous to environmental organisms.