The etiology of Parkinson's disease (PD) is still not fully clear, but several studies have implicated metals as cofactors of risk. To assess a potential]imbalance in the trace elements concentration of hair of subjects affected by PD, the content of Al, Ba, Cd, Co, Cr, Hg, Mn, Me, Ph, Sri, Sr and Zr in 81 patients affected by PD and 17 age-matched controls was determined. Quantification of the elements was performed by inductively coupled plasma mass spectrometry. Results indicated significantly lower levels of Ph in the hair of patients (p <= 0.05) compared with controls. Manganese was slightly higher while Ba, Sri and Sr levels were lower in patients, although these differences were not significant, no variations in Al, Cd, Co, Cr, Mo and Zr levels were observed in PD. Barium and Sr in hair were higher in women than in men in both controls and patients. In addition, again Ba and Sr of patients decreased with age with a p < 0.0 1 for both elements. Finally, a decreased value of Ph with the duration and the severity of the disease and Hg with the severity duration of the pathology were observed.