Aluminium ammonium bis(sulphate)

Endpoint summary

Additional information

Aluminium ammonium sulfate will dissociate in moisture soils in its two component salts (aluminium sulfate and ammonium sulfate) and finally to SO4 2-; NH4+l and Al3+ ions. Therefore, the hazard of this salt for the terrestrial environment can be assessed by the effects of its dissociation products in a read across approach as justify in the Ecotoxicological information endpoint summary.

Aluminium

As aluminium is the third most common element in the earth’s crust, the literature is voluminous and the reviews, together with the number of reference papers on which they are based, that have been used in the compilation of this submission are the most recent and are listed below.

- ATSDR (2008). Agency for Toxic Substances and Disease Registry. Toxicological profile for aluminium. September 2008.

- Environment Canada and Health Canada (2010). Priority Substances List Assessment Report for Aluminium chloride, Aluminium nitrate and Aluminium sulphate, January 2010.

- WHO (1997). Environmental Health Criteria 194. United Nations Environment Programme, International Labour Organisation, World Health Organization, International Programme On Chemical Safety.

Aluminium (Al) is a major component of almost all common inorganic soil particles, with the exceptions of quartz sand, chert fragments, and ferromanganiferous concretions. The typical range of aluminium in soils is from 1% to 30% (10,000 to 300,000 mg Al kg-1), with naturally occurring concentrations varying over several orders of magnitude. Terrestrial organisms are exposed to added aluminum when alum sludge from water treatment facilities is applied to agricultural soils. Aluminum is found in the soil complexed with other anions, such as fluoride, sulfate, and phosphate. In general, the solubility and mobility of aluminum in soil is greatest when the soil is rich in organic matter capable of forming aluminum-organic complexes and when the pH is low, such as in areas prone to acid rain or in acidic mine tailings.

Toxicity data were reported for earthworms, plants, microorganisms and birds. According to the results, the potential ecological risks of aluminium are identified only at sites where the soil pH is less than 5.5. Under circum neutral to alkaline (pH 5.5-8.0) conditions, aluminium is forming hydroxide complexes, precipitating to gibbsite and the risks for soil organisms are negligible because aluminium is biologically inactive.

Ammonium The SIDS Initial Assessment Report (OECD SIDS, 2004) reports the terrestrial effects of ammonium sulfate. In the terrestrial environment, the major effect of repeated ammonium sulfate application is a reduction in soil pH. However, under the proposed conditions of use aluminium ammonium sulfate salt won't be apply directly to the soil but might reach the terrestrial compartement already diluted in water and therefore a pH effect is not expected. Moreover, in unsterilized soil, ammonium sulfate is mineralized fairly rapidly, and subsequently nitrified. From these data it can be postulated that under environmental conditions and proposed conditions of use no adverse effects on terrestrial organisms would result from the use of aluminium ammonium sulfate.