Toxicity tests:
Eco-toxicity_Assessment_Report-May_2010-Final.pdf (page 3 of executive summary, last paragraph)
Bioaccumulation:
7_Wilfrid Laurier review.pdf (table 7 page 29)
In the first link I posted on my previous post, summary paragraph at beginning of paper, it mentions that a white precipitate had accumulated on cells of the bacteria tested. They believe it to be lanthanum phosphate crystals.
Both research papers that you provided links to are most thorough and informative.
A couple of scientific facts need to be emphasized prior to discussion of the potential toxicity of Lanthanum.
1. All Heavy metals are considered toxic a certain levels. Some, like Copper, can reach high toxicity at relatively low levels when compared to other metals such as Iron.
2. All Heavy Metals are bio-accumulates. The rate of bio-accumulation also widely varies among the metals.
3. Toxicity will vary based on water hardness and in some case pH.
In both studies covered in the two (2) papers, Lanthanum chloride was used in its undiluted form, or full-strength, if you will. In commercial Lathanum based Phosphorus binders the LaCl is offered in an already diluted form with plainly stated dosing instructions. Upon application, the LaCl binds with the Phosphorus in the water column usually first because of the stronger ionic attraction forming a stable LaPo4. This Lanthanum is no longer reactive and can not bond with or affect any aquatic organism and settles out of the water column as a precipitate. Again, this is where following the dosing instructions is all important.
Lanthanum Chloride is widely used in both fresh and salt water aquaria and in both small and very large facilities. It has been used for years with no ill-effects to the individual aquatic communities.
Mis-use and/or over use of this or any other water treatment will certainly cause toxicity issues.
I only recommend its use for controlling filamentous algae growth or to reduce the Phosphorus level to below 0.05 mg/L. It should not be used if Phosphorus levels are below 0.05 mg.L. Instead a Phosphorus adsorber, such as Ferric Iron can be used to maintain the lower P levels.
but what's different between the one in the website saying its 100% and one on ebay say 99%.... Does that even matter?
