Reaction mass of aluminium hydroxide and aluminium nitrate and aluminium sulphate

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

no data available: testing technically not feasible

Marine water

Hazard assessment conclusion:

no data available: testing technically not feasible

STP

Hazard assessment conclusion:

no hazard identified

Sediment (freshwater)

Hazard assessment conclusion:

insufficient hazard data available (further information necessary)

Sediment (marine water)

Hazard assessment conclusion:

insufficient hazard data available (further information necessary)

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

insufficient hazard data available (further information necessary)

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

Available data indicate that aluminium salts are relatively non toxic in most waters with circumneutral pH and this was sufficient for the EU Classification and Labelling Committee (1999) to determine that there was no need for classification of aluminium chloride. Therefore it was also concluded that aluminium salts are not toxic to the environment. Based on the available data, it is proposed from the CEPA that the three aluminum salts, aluminum chloride, aluminum nitrate and aluminum sulphate, are not entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity or that constitute or may constitute a danger to the environment on which life depends (Environment Canada and Health Canada, 2008).

Aluminium ions released to surface waters quickly form insoluble aluminium hydroxides in mixing zones. These colloids can sorb to fish gills resulting in asphyxiation and mortality in rare circumstances. Formation of the complex hydroxide causes the aluminium to drop out of solution very rapidly in neutral and alkaline waters. The dissolved natural background concentrations of aluminium, in most cases, are at equilibrium therefore an addition of aluminium would lead to the precipitation of aluminium compounds from solution and not result in effects to aquatic life. We conclude that a PNEC is not required for REACH. However, the aluminium industry is continuing its efforts to develop a PNEC for freshwater ecosystems for purposes of the Water Framework Directive. 

The long term goal of the industry is to develop an aquatic PNEC that covers the pH range of < 6, 6-7, and > 7. These pH ranges reflect that the form of Al present in water changes significantly as a function of pH.  Scientists around the world have worked towards a PNEC for Al for the past 30 years. The aluminum industryis continuing its efforts to develop a PNEC for freshwater ecosystems for purposes of the Water Framework Directive. 

Conclusion on classification

Available data indicate that aluminum salts are relatively non toxic in most waters with circum neutral pH and this was sufficient for the EU Classification and Labelling Committee (1999) to determine that there was no need for classification of aluminum chloride. Other aluminum compounds act similarly in water as aluminum chloride and are in many cases less soluble and non-hazardous.

Studies reported in the literature have extensively used test solutions (soluble salts) with aluminum concentrations above that of its solubility limit. Due to physical effects of precipitated material most of these studies are meaningless for the investigation of intrinsic toxicity. Aluminum ions released to surface waters quickly form insoluble aluminum hydroxides in mixing zones. Formation of the complex hydroxide causes the aluminum to drop out of solution very rapidly in neutral and alkaline waters.

The dissolved natural background concentrations of aluminum, in most cases, are at equilibrium therefore an addition of aluminum would lead to the precipitation of aluminum compounds from solution and not result in effects to aquatic life.

 

In conclusion, the reaction mass of aluminium hydroxide and aluminium nitrate and aluminium sulphate is not classified as hazardous to the aquatic environment according both to 67/548/EEC and Regulation (EC) 1272/2008 (self Classification).