Assessment of persistent, bioaccumulative and toxic organic environmental pollutants in liver and adipose tissue of alzheimer’s disease patients and age-matched controls

Background: Lifetime exposure to environmental (neuro) toxicants may contribute to the pathogenesis of Alzheimer’s Disease (AD). Since many contaminants do not cross the blood-brain barrier, brain tissue alone cannot serve to assess the spectrum of environmental exposures. Methods: We used liquid and gas chromatography tandem mass spectrometry to monitor, in postmortem liver and adipose tissues of AD patients and age-matched controls, the occurrence and concentrations of 11 environmental contaminants. Results: Seven toxicants were detected at 100% frequency: P,p’-DDE, dieldrin, triclosan, methylparaben, bisphenol A, fipronil and tetrabromobisphenol A (TBBPA). Intra-individual, tissuedependent differences were detected for triclosan, methylparaben, fipronil and TBBPA. High concentrations of p,p’-DDE and dieldrin were observed in adipose tissue when compared to liver values for both AD cases and controls. Conclusion: This study provides vital data on organ-specific human body burdens to select analytes and demonstrate the feasibility of analyzing small sample quantities for toxicants suspected to constitute AD risk factors.