Effects of household pollutants on the metallothioneins in tissues of bivalve molluscs Unio tumidus

Personal care products and pharmaceuticals are the most common novel water pollutants, and it is difficult to predict the effects. It is expected that they can modulate the activity of molecular detoxification systems. Since the production of the metal-binding proteins, metallothioneins (MTs) are activated by a wide range of stress factors, the aim of the study was to compare the functional characteristics of the MTs from digestive gland (DG) of male bivalve mollusc Unio tumidus from reference pond, polluted by sewage effluents pond and after the exposure to widespread water personal care pollutants ibuprofen (I, 250 ng / L), triclosan (T, 500 ng / L) or estrone (E1, 100 ng / L) for 14 days (overall term of staying in the laboratory aquaria – 21 days). The elevation of the content of zinc, copper and cadmium in bivalves’ tissues of DG, gonads and MTs as well as total level of MTs was noted in polluted pond compared to the reference one. Exposure factors and chronic pollution caused an increase of level of Zn-binding MT form on a background of reduced (I-, T-group) or increased (E1 group) total protein content of MTs and constant total level of zinc and copper in tissue. Under the effect of I, T and E1, marked decreasing in copper level and increasing (in 2.2–3 times) in zinc level were observed in the gonads. Thus, we should assume that the elevation of the content of zinc-MT in the bivalves DG can be considerded as the compound of the unspecific supporting strategy of the signa­ling function of these ions under the harmful efects