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A glass electrode can be made to withstand high hydrostatic pressure, up to 1500 kg/cm2, by separating the inside fluid from the outside one with a layer of silicone oil acting as a liquid piston, enabling the inside and outside pressure to compensate continuously. Such a glass electrode, with two Ag–AgCl electrodes, maintains its hydrogen electrode function at high pressure. pH changes resulting from dissociation constant shifts caused by pressure in acid and buffer solutions have been measured in good agreement with theoretical expected values for HCl, acetic acid, carbonic acid, and acetate buffer. No agreement was found for bicarbonate buffer. Phosphate buffer and sea water have also been tested. An adapted version of the cell-assembly is planned to equip the French bathyscaphe for deep-sea investigations.

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The study of metal concentrations in Patella vulgata caught from a polluted environment reveals a direct relationship between Cd concentration and body size and an inverse relationship in regard to Zn and Cu. Most of the Cd present in limpets with heavy Cd loads is bound to thioneins, but this is not the case for Zn and Cu. In young limpets, Cd-thioneins were not detected. All results indicate that during long-term Cd intoxication under field conditions, Cd deposition and increase in metallothioneins in limpets were directly linked. The induced production of metallothioneins may thus be considered as the main mechanism responsible for the cumulative absorption of Cd in limpets living in the Bristol Channel. Isolation and characterization of limpet metallothioneins were performed. They indicate that mollusc metallothioneins are very similar to those from vertebrates.