Lead content in autopsy liver tissue in samples from Greenlandic Inuit and Danes

Objectives: To measure the quantity of lead (Pb) in liver tissue samples from Greenlandic Inuit, and compare the results with those obtained in Caucasian Danes. Study design: Observational, descriptive survey on environmental pathology. Methods: The setting was related to forensic medicine and hospitalised care in Nuuk, Ilulissat and Copenhagen. Participants were 50 Greenlandic Inuit (27 men) with a median age of 61 years (range 23–83) and 74 Danes (44 men) with a median age of 60 years (range 15–87). Liver tissue samples (normal by macroscopic and microscopic examination) were obtained at autopsy. Total liver lead content was measured by X-ray fluorescence spectrometry with a detection limit of 0.05 μmol/kg dry weight. Results: In the entire series, Inuit had higher liver lead contents than Danes (p < 0.0001). Inuit men had higher liver lead content than Inuit women (p = 0.02). In Danes, men tended to have higher liver lead contents than women, but the difference was insignificant. The median (5–95 percentile) lead content was 14.96 μmol/kg dry liver (4.83–74.80) in Inuit, and < 0.05 μmol/kg dry liver (< 0.05–29.44) in Danes. All Inuit had liver lead contents above the detection limit, whereas 60 Danes (81%) had liver lead content below the detection limit. There was a positive correlation between liver lead content and age in both Inuit (rs = 0.46, p = 0.002) and Danes (n = 14; rs = 0.71, p = 0.01). Inuit had higher hepatic lead indices (liver lead content divided by age) than Danes (p < 0.0001). In Inuit, median hepatic lead index was 0.258, being higher in men than in women (p = 0.02). In Danes, the median hepatic lead index was 0.001, again higher in men than in women (p = 0.03). Conclusions: Our results show a gender-related difference in hepatic lead content, i.e. Inuit men have higher liver lead contents than women. Furthermore, Inuit men and women have higher hepatic lead contents than Danish men and women. In both Inuit and Danes, the liver lead content increases with age. One reason for thehigh lead levels in Inuit may be ingestion of seabirds contaminated by lead shot.