Solubility and toxicity of resin acids

The solubilities of the eight most common resin acids have been measured using a solid phase extraction and gas chromatography determination. Their acute toxicity has also been determined by a bioassay procedure using Daphnia magna as LC50 values following different periods of exposure and the toxicity has been shown to correlate well with fish toxicity measurements using rainbow trout (Salmo gairdneri). The solubility and toxicity of individual resin acids have been shown to be structure dependent. Dehydroabietic acid is the most soluble, and the pimaric type resin acids are the least soluble. Toxicity has also been found to correlate inversely with solubility. Isopimaric acid is the most toxic and least soluble acid, whilst dehydroabietic acid is the least toxic and most soluble. Pimaric type resin acids are more toxic and less soluble than the abietic type.