Autor(es): Barros, Rafael ; Pastorinho, M. Ramiro ; Valente, João Vasco ; Souto-Miranda, Sara ; Marques, Alda ; Valente, Carla ; Taborda-Barata, Luís ; Sousa, Ana C. A.
Data: 2020
Identificador Persistente: http://hdl.handle.net/10773/30605
Origem: RIA - Repositório Institucional da Universidade de Aveiro
Assunto(s): Blood; Hair; Urine; Nails; Mercury; Non-invasive matrices
Humans are exposed to mercury trough several pathways including the consumption of contaminated seafood and ingestion of contaminated house dust. We have previously demonstrated that mercury levels in house dust samples from Estarreja region are amongst the highest reported in Portugal. Here we report the levels of total mercury in different biological matrices from 88 adult individuals from Estarreja (age: 37-83, median: 68). Mercury was detected in all samples analysed, with the highest levels being found in hair (range: 560-4540 ng/g, median: 1680 ng/g), followed by fingernails (range: 215-1740 ng/g, median: 844 ng/g), toenails (range: 144-1850 ng/g, median: 555 ng/g), blood (range: 0.97-18.4 ng/g, median: 6.70 ng/g) and urine (range: 0.15-5.14 ng/g, median: 0.61 ng/g). The hair to blood ratio (H:B) varied between 147 and 616, with a median value of 274, which is only 9% higher than the H:B ratio proposed by the Word Health Organization . The concentrations of mercury in hair were very strongly correlated with the concentrations in blood (p<0.001, Pearson r =0.871), and strongly correlated to fingernails (p<0.001, Pearson r =0.735) and toenails (p<0.001, Pearson r =0.639) whereas no correlation between the levels in hair and urine were found (p=0.25, Pearson r =0.208). Similarly, urine levels were not correlated with those found in nails (p>0.001). Such results suggest that a urine levels reflect the exposure to a different species of mercury, reinforcing previous studies that propose urine as a suitable matrix for inorganic mercury whereas blood, hair and nails are suitable matrices for methylmercury exposure.
