Aluminium Toxicity pH Variable

Long-term toxicity to aquatic invertebrates

Toxicity decreased with increasing pH

Aluminium toxicity was reduced at high pH, but a larger reduction was observed when changing pH from 6 to 7 than from 7 to 8. 

https://echa.europa.eu/registration-dossier/-/registered-dossier/15529/6/2/5

Literature Review: Six long-term chronic toxicity studies to two species of aquatic invertebrates(Ceriodaphnia dubia and Daphnia magna) were identified as acceptable studies.

See Table # “Overview of long-term effect on aquatic invertebrates” (below). EC_r10s were calculated using raw data provided from each study using the statistical program Toxicity Relationship Analysis Program (TRAP) version 1.10 from the US EPA National Health an Environmental Effects Research Laboratory (NHEERL).

All other endpoints were as reported in each study. NOECs and EC10s ranged from 0.076 to 4.9 mg Al/L and 0.021 to 0.997 mg Al/L, respectively. Water quality data for these studies suggest a direct relationship between toxicity and pH, hardness, and DOC. For studies that experimentally manipulated water quality (e.g., CIMM 2009 and 2010a ), toxicity decreased with increasing pH, hardness, and DOC.

Aluminum and water: reaction mechanisms, environmental impact and health effects

Aluminum naturally occurs in waters in very low concentrations. Higher concentrations derived from mining waste may negatively affect aquatic biocoenosis. Aluminum is toxic to fish in acidic, unbuffered waters starting at a concentration of 0.1 mg/L. Simultaneous electrolyte shortages influence gull permeability, and damage surface gull cells. Aluminum is mainly toxic to fish at pH values 5.0-5.5. Aluminum ions accumulate on the gulls and clog these with a slimy layer, which limits breathing. When pH values decrease, aluminum ions influence gull permeability regulation by calcium. This increases sodium losses. Calcium and aluminum are antagonistic, but adding calcium cannot limit electrolyte loss. This mainly concerns young animals. An aluminum concentration of 1.5 mg/L turned out to be fatal to trout. The element also influences growth of freshwater bony fish.

Full : https://www.lenntech.com/periodic/water/aluminium/aluminum-and-water.htm#ixzz5xTLuYJaV

Choose Life : Considering what is happening in the world in these times, these studies about aquatics, helps link so much together. This post will be updated as I find more data on this, just started a new job so bare with me please.