Bioaccumulation of water soluble aluminium chloride in the hippocampus after transdermal uptake in mice.

Normally, only very small amounts of ingested aluminium are absorbed and accumulated. Despite the percutaneous absorption of many drugs and chemicals, the skin has not been considered as a possible site at which aluminium could enter the body. Application of low aqueous concentrations of aluminium chloride (A1C1(3), 6H20) (0.025-0.1 micrograms/cm2) to healthy shaved Swiss mouse skin for 130 days led to a significant increase in urine, serum and whole brain aluminium, especially in the hippocampus, compared to control animals. This percutaneous uptake and accumulation of aluminium in the brain was greater than that caused by dietary exposure to 2.3 micrograms per day in feed and water. In vitro studies demonstrated the passage of aluminium through viable mouse skin. This study shows for the first time that aluminium is absorbed through the skin of mice in vivo and this contributes to a greater body burden than does oral uptake.

[Physico-chemical fate of copper intrauterine devices]. / Devenir physico-chimique des stérilets au cuivre.

Often when copper intra-uterine contraceptive devices are removed they are found to have deposits on them. Studying these deposits with photonic microscopes and with scanning electronic microscopes and with fluorescence X and X diffraction shows that mostly these deposits are of calcium in the form of calcite. These crystals are not toxic but the fact that they are crystalline could give rise to microtraumatism. The study also shows that there are individual variations between patient and patient and the length of time these intra-uterine devices have been in the uterus is not an important factor in the appearance of these deposits. The phenomenon of dissolution and recrystallisation in situ of the calcite can be a trap because it can be a reservoir for micro-organisms.