Inhibition of cellular efflux pumps involved in multi xenobiotic resistance (MXR) in echinoid larvae as a possible mode of action for increased ecotoxicological risk of mixtures.

In marine organisms the multi xenobiotic resistance (MXR) mechanism via e.g. P-glycoprotein (P-gp) and multidrug resistance-associated protein (MRP) is an important first line of defense against contaminants by pumping contaminants out of the cells.

Early life developmental effects of marine persistent organic pollutants on the sea urchin Psammechinus miliaris.

A new 16-day echinoid early life stage (ELS) bioassay was developed to allow for prolonged observation of possible adverse effects during embryogenesis and larval development of the sea urchin Psammechinus miliaris. Subsequently, the newly developed bioassay was applied to study the effects of key marine persistent organic pollutants (POPs). Mortality, morphological abnormalities and larval development stages were quantified at specific time points during the 16-day experimental period.