Dialuminium chloride pentahydroxide

Short-term toxicity to aquatic invertebrates

Description of key information

OECD guideline 202, GLP, key study, validity 2 (Schafers, 2004, static test), aluminium trichloride:

48h-EC50 = 0.214 - 1.26 mg/L (based on measured intial concentrations, dissolved aluminium)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.214 mg/L

Additional information

Eight read-across studies are available : two on Aluminium sulphate-14-hydrate, one on aluminium sulphate, one on aluminium octadecahydrate, two on aluminium trichloride and two on Aluminium chloride hydroxide sulphate.

1-              This first read-across study available was performed to evaluate the acute toxicity of aluminium sulphate-14-hydrate to Daphnia magna under semi-static conditions (daily renewal of the test medium) for 48 hours. Up to the highest test concentration, no immobility could be observed after 48 h. The NOEC of aluminium sulphate-14-hydrate under the described study conditions was determined as follows: NOEC ≥ 160 mg aluminium sulphate-14-hydrate / L and exceed the water solubility at the tested pH levels.

 

2-              This second read-across study was performed on aluminium sulphate-14 -hydrate. NOEC and LOEC determinations are considered not approriate according to the arguments of the authors. Expert judgement therefore states that only the EC10 and EC50 should be used for risk assessment. Furthermore, the EC50 determined for the dissolved amount of aluminium was calculated as the geometrical mean between the two highest measured concentrations between 0 and 100% effect. However, expert judgement states that the EC50 should have been determined as the geomean between 0.176 mg/L (first observed effect) and 0.468 (mg/L). Since the result of this adaptions should be a marginal difference, we can accept the value of 0.33 mg/L, calculated by the authors.

 

3-              This third read-across study was performed on aluminium sulphate. the acute immobilisation test with Daphnia, the LOEC was determined to be 750 mg/L ALS to Daphnia magna, The EC50 was determined to be 870 mg/L ALS. No reference test was used, as prescribed by the guideline. The test was performed according to the OECD 202 guideline. Most validity criteria have been met.

 

4-              This study aimed to evaluate the toxic effect of aluminium octadecahydrate on Daphnia magna and Selenastrum capricornutum at their possible residual concentrations simulating coagulation-flocculation process effluent. Alum concentration varied from 0.1 mg/l to 1 mg/l. Anionic polymer was then added as 0.5 mg/l, 1 mg/l, 1.5 mg/l and 2 mg/l to alum solution. The EC10 and EC50 were determined according to a ISO and EPA guideline, no data on GLP is presented. The EC10 and EC50 (both nominal) were, 755 and 782 ug/L, respectively.

 

5-              This study aimed to evaluate the acute toxicity of Gilufloc 40 H (aluminium trichloride) to Daphnia magna relevant for an accidental exposure. At the highest test concentration, the mean measured dissolved aluminium concentrations increased to 1.4 mg/L due to pH which was decreased to 5.1 by the test item. The EC50 of the test item was determined to be 38 mg test item /L (95 % confidence limits: 31 – 47 mg/L). Since no aluminium was observed at nominal test substance concentration above the LOD, effects could not have been caused by aluminium. Therefore the EC50 suggested by the authors could not be supported. In the control group, however, aluminium was observed and in the highest concentration Al was observed. Expert judgement therefore states the EC50 based on measured free Al to be between 0.212 and 1.26 mg/L.

 

6-              This study aimed to evaluate the acute toxicity of Gilufloc 40 H (aluminium trichloride) to Daphnia magna, under semi-static conditions (daily renewal of the test medium) for 48 hours. After subtraction of the background, all mean dissolved Al concentration were < 0.1 mg/L, irrespective of the applied amount of total aluminium. However, the immobility of daphnids indicates a clear concentration-response relationship when based on the test item. The resulting EC50 of the test item was determined to be EC50 = 98 mg test item/L (95 % confidence limits: 77 – 126 mg/L). Thus it is concluded that toxicity is driven by other causes than dissolved aluminium.

 

7-              This static test was run for 48h on Daphnia magna to evaluate the acute toxicity of aluminium chloride. The EC50 was found to be above 200 mg/L. While a number of details are not available and the analytical data only makes sense when the values from T0 and T48 are inversed, this does not impact the validity of the study as effects were greater than the maximum loading rate of the test substance used and thus greater than the solubility limit of the dissolved aluminium concentration measured in the study.

 

8-              This study aims to evaluate the toxicity of AQUALENCE F to Daphnia magna, for 48 hours (aluminium chloride). The nominal test concentration was 100 mg/L. Analysis showed 0.07 mg/L Al3+ as backgroud noise. No toxicological effects were observed. The NOEC was determined to be 100 mg/L nominal and 0.15 mg/L actual Al3 +. Expert judgement states that the NOEC should be 0.22 mg/L actual Al3 +. Analysis was performed but is very questionable. Concentrations on the analysis report do not match test concentrations as well as test date (range finding). The measured concentrations in the limit test have a high variance (around a factor 3). The conclusion from the range finding test also is questionable (since 0.1, 1.0 and 10mg/L were tested and the conclusion from the range finding is that the NOEC here is 100 mg/L).