Parkinson’s disease among Inuit in Greenland: organochlorines as risk factors

Abstract

Objectives. In the present study we investigate organochlorines as possible risk factors for Parkinson’s disease (PD) in an arctic population. This has never been done before. Study design. Case-control study of Inuit in Greenland. Materials and methods. Plasma from 31 PD (20 males and 11 females) (mean age 69 yr) and 122 controls (57 males and 65 females) (mean age 61 yr) was analysed for 31 PCBs and pesticides by dual-column GC-ECD and GC-NCI/MS. Results. Plasma concentrations of PCBs and pesticides were markedly increased in both PD and controls. The concentrations did not differ between the PD cases and controls. However, the mean DDE concentration was higher in PD than in controls (42.1 and 15.0 μg/l, respectively, and with a wide range among the PD cases). The difference was significant for log transformed DDE values after control for age and sex (p=0.005). Conclusion. A few epidemiological studies indicate a possible connection between exposure to pesticides and PD. The idea that exposure to organochlorines may be an important risk factor for PD among the Inuit in Greenland requires more investigations.

Key Words:

• Parkinson’s disease
• Inuit
• organochlorines
• case-control study