Fluoride bioaccumulation in the signal crayfish Pacifastacus leniusculus (Dana) as suitable bioindicator of fluoride pollution in freshwater ecosystems

► Exoskeleton bioaccumulates higher fluoride levels than muscle in signal crayfish. ► Water chloride content reduces fluoride bioaccumulation in signal crayfish. ► Sex does not affect significantly fluoride bioaccumulation in signal crayfish. ► Juvenile signal crayfish release fluoride during depuration periods. ► Fluoride bioaccumulation in signal crayfish as bioindicator of fluoride pollution.