Daily Archives: March 22, 2015

Chloride an Inconsistent Modifying Factor for Fluoride Aquatic Toxicity

Pearcy K, Elphick J, Burnett-Seidel C. Toxicity of fluoride to aquatic species and evaluation of toxicity modifying factors. Environmental Toxicology and Chemistry 2015 Mar 2. doi: 10.1002/etc.2963.

A study was performed to investigate the toxicity of fluoride to a variety of freshwater aquatic organisms and to establish whether water quality variables contribute substantively to modifying its toxicity. Water hardness, chloride and alkalinity were tested as possible toxicity modifying factors for fluoride using acute toxicity tests with Hyalella azteca and Oncorhynchus mykiss. Chloride appeared to be the major toxicity modifying factor for fluoride in these acute toxicity tests. The chronic toxicity of fluoride was evaluated with a variety of species, including three fish (Pimephales promelas, O. mykiss and Salvelinus namaycush), three invertebrates (Ceriodaphnia dubia, H. azteca and Chironomus dilutus), one plant (Lemna minor) and one alga (Pseudokirchneriella subcapitata). H. azteca was the most sensitive species overall, and O. mykiss was the most sensitive species of fish. The role of chloride as a toxicity modifying factor was inconsistent between species in the chronic toxicity tests.

Paper is here (Open Access).