Behavioural and Electrophysiological Characterization of an Unknown Water Soluble Anaesthesia-Inducing Agent Found in Common Adhesive Tape

Immersion of a ubiquitously used brand of translucent pressure sensitive adhesive tape (TLPSAT), in normal water was found to confer anaesthetic-like effects to the resultant solution (TLPSAT A). We characterised this anaesthetic-like property by assessing its dose-dependence, behavioural effects and toxicity in zebrafish (Danio rerio) in comparison to other commonly used anaesthetics, namely 2-phenoxyethanol (2-PE) and tricaine methanesulfonate (TMS). Toxicity tests showed that it is comparable to TMS and safer than 2-PE in terms of mortality. We also observed differences in the nature of opercular movement due to the three compounds with differences in the power spectrum. Electrophysiological investigations using grasshopper (Hieroglyphus banian) as a model system led us to conclude that nicotinic acetylcholine (nACh), γ-aminobutyric acid (GABAergic) mechanisms, or voltage gated calcium (Ca2+), sodium (Na+) and potassium (K+) channels in insects are not affected by this anaesthetic at the concentrations effective in fish. Electroretinography (ERG) measurement from honeybees (Apis mellifera) in the presence of the different compounds yielded abolishment of the receptor potential under TMS or 2-PE perfusion whereas all ERG components were preserved under TLPSAT A perfusion, indicating that the Ca2+ dependent channels and photo-transduction machinery in bees are not potentially affected by TLPSAT A. Thus, the unknown compound(s) in the TLPSAT aqueous extract likely induce(s) anaesthesia in zebrafish via a mechanism unlike that of TMS and 2-PE.