[Detection of metal ions in hair after metal-metal hip arthroplasty]. / Detección de iones metálicos en cabello tras artroplastia de cadera metal-metal.

OBJECTIVE: There is an increase in the levels of metals in the serum and urine after the implantation of some models of metal-metal hip prosthesis. It has recently been demonstrated that there is an association between these levels and the levels found in hair. The aim of this study is to determine the presence of metals in hair, and to find out whether these change over time or with the removal of the implant. MATERIAL AND METHOD: The levels of chromium, cobalt and molybdenum were determined in the hair of 45 patients at 3, 4, 5, and 6 years after a hip surface replacement. The mean age was 57.5 years, and two were female. Further surgery was required to remove the replacement and implant a new model with metal-polyethylene friction in 11 patients, 5 of them due to metallosis and a periarticular cyst. RESULTS: The mean levels of metals in hair were chromium 163.27 ppm, cobalt 61.98 ppm, and molybdenum 31.36 ppm, much higher than the levels found in the general population. A decrease in the levels of chromium (43.8%), molybdenum (51.1%), and cobalt (91.1%) was observed at one year in the patients who had further surgery to remove the prosthesis. CONCLUSIONS: High concentrations of metals in the hair are observed in hip replacements with metal-metal friction, which decrease when that implant is removed. The determination of metal ions in hair could be a good marker of the metal poisoning that occurs in these arthroplasty models.

Metal distribution patterns in the mussel Mytilus edulis cytosols using size-exclusion chromatography and double focusing ICP-MS detection.

In order to estimate metal distribution patterns in biomolecules of different sizes and their possible relationship with environmental heavy metal contamination, multi-elemental distributions in different fractions of the cytosols of mussels were studied. To do so, samples were collected from natural populations of two coastal regions in Spain: a wild (uncontaminated) coast and an industrialised (contaminated) area in Asturias. Moreover, some commercial mussels from the Galicia coast were also investigated for comparison. Aliquots of the mussel cytosol extracts from each sample were applied to a calibrated Sephadex G-75 column (100 x 1 cm) and forty 3 ml fractions were obtained. After suitable dilution, 18 trace metals were determined by double focusing inductively coupled plasma mass spectrometry (DF-ICP-MS). The use of DF-ICP-MS detection allowed the resolution of several spectral interferences that cannot be resolved by quadrupole ICP-MS. Accurate results for ultratrace elements at basal levels are possible even after sample dilution to prevent matrix effects. After biomolecule-metal association pattern has been established, quantitative analysis of mussel cytosols from the three coastal areas was carried out, using external aqueous calibration plus standard additions to correct for possible matrix effects. Results showed that total metal contents increased following the expected order: wild coast < Galicia coast < industrial area coast. Speciation of Cu, Zn, Ca, U, Ni, Mo, Mn, Cr, V, Cd, Al and Sb showed a similar distribution pattern among cytosolic ligands for all the studied samples. Conversely, Fe, Pb, Sn, Co, Hg and Ag were found to exhibit different speciation patterns when samples from industrialised (contaminated) and non-industrialised areas were compared.