A 30-Min Exposure on Permethrin and Deltamethrin Modifies Ion Transport Pathways in the Skin.

Pyrethroids are pesticides used in agriculture, the textile industry, wood processing, and human and animal medicine. Pyrethroids inhibit voltage-sensitive sodium channels (VSSCs) in insects and mammals. It results in the premature opening and/or delayed closing of the channels, causing a prolonged influx of Na ions into the cell. Insects absorb pyrethroids throughout the entire body surface, while poisoning in humans most often occurs by inhalation and through the skin. In this study, 52 fragments of human skin taken from the eyelid fold were examined. A modified Ussing chamber was used to measure the active ion transport in epithelial tissue and quantify the tissue viability and integrity. Both permethrin and deltamethrin solutions induced changes in the transport of ions, mainly sodium, but by different mechanisms. Permethrin affected the transepithelial transport of sodium ions in a long-term mechanism, while deltamethrin affected the ability to respond to stimuli in an immediate mechanism. Contact with deltamethrin may cause a delay/slowness of sensation, inflammation, hypersensitivity, and/or allergy. The action of permethrin takes place in the intercellular spaces and is associated with the possibility of faster decomposition/metabolism, while deltamethrin interacts with receptors, channels, and the cell membrane, which translates into slower decomposition and longer action in the tissue.