Bioaccumulation of mineral elements within the vestimentiferan tube worm Riftia pachyptila (Jones): A review.

The bioaccumulation of several elements in the tissues of the vestimentiferan worm Riftia pachyptila, collected at various sites of the East Pacific Rise, has been evidenced. Important fluctuations of elemental levels are observed among specimens originating from different sites, or even from the same site. These fluctuations are related to the exposure of the sampled organisms and to the high variability of the vent fluids (frequency, duration, intensity, direction, chemistry). The storage of the elements as mineral compounds and the abundance of metallothioneins are responsible for their apparent lack of toxicity, and provide evidence of existing detoxication processes. Cadmium, copper and zinc have been quantified in the blood, leading to the hypothesis of the existence of a metal carrier responsible for their transportation from the plume toward the trophosome. These metals have also been quantified for the first time within isolated symbiotic bacteria and coelomic liquid.