Aluminum chloride, basic

Endpoint summary

Additional information

The available evidence shows the absence of aluminium biomagnification across trophic levels both in the aquatic and terrestrial food chains. The existing information suggests not only that aluminium does not biomagnify, but rather that it tends to exhibit biodilution at higher trophic levels in the food chain.

Metal concentrations in tissue based on a range of exposure concentrations may be quite similar but the BCFs will be quite variable reflecting an inverse relationship (i.e., higher BCFs at lower exposure concentrations and lower BCFs at higher exposure concentrations) between metal concentrations and the corresponding BCF (McGeer et al, 2003). From the above it is clear that any conclusion based on the application of classical concepts (e.g., use of bioconcentration factors; BCF -biomagnification factors; BMF) to assess metal hazards as they are applied to organic substances should be treated with caution.

More detailed information can be found in the attached document (White paper on waiving for secondary poisoning for Al & Fe compounds final report 02-02-2010. pdf). BCFs for Aluminium can be found to range from quite low (~100) to very high values (11,000) The inverse relationship between water and BCF/BAF values limits the ability to describe hazard as a result of the size of the BCF, i. e., the most pristine ecosystems have the highest BCFs. A better approach is to directly assess the concentrations of Al at various trophic levels in the ecosystem.

Herrmann and Frick (1995) studied the accumulation of aluminium at low pH conditions in benthic invertebrates with time and representing different functional feeding groups (predators and detritus feeders). Invertebrates of different taxa and feeding type were collected in springtime, when acidity and A1 levels mostly increase from seven streams in southern Sweden. Four of the streams typically had pH values of 4 - 4.5 and contained 0.40 - 0.70 mg inorganic A1/L. The other three streams showed pH values around 6 and A1 concentrations of 0.05 mg inorganic A1/l. For most taxa that could be compared, the animals from the most acidic streams (pH 4) contained more A1 than those from the less acid streams (pH 6). At both pH levels there was a clear tendency that predators contained significantly less amounts of aluminium than shredders. The latter results do not support the hypothesis that aluminium can be accumulated along a food chain in an acidic environment.

See Annex for White paper on waiving for secondary poisoning