Toenail selenium as an indicator of environmental exposure: A cross-sectional study.
The relation between toxicity and essentiality of selenium (Se) is of growing interest in human health, as the effects may widely differ depending of its different chemical species and the exposure levels. Toenail Se has been proposed as a reliable biomarker of long-term Se exposure, but few studies investigated the correlation between its toenail content and environmental determinants (i.e., dietary food intake). We aimed to determine the relation of toenail Se levels with serum Se species as well as food items. We recruited a random sample of Modena (Northern Italy) municipal residents, from whom we collected detailed personal information, dietary habits, toenail specimen for Se determination and a blood sample for serum Se speciation analysis. Toenail Se mean value was 0.96 µg/g (range, 0.47‑1.60), with slightly higher levels in females, in non-obese subjects and in Se supplements users, while it was lower in current smokers. Toenail Se positively correlated with organic Se forms, mainly selenoprotein P and selenocysteine, and inversely with the inorganic forms (selenite and selenate). Toenail Se was not associated with meat, cereals and dairy products consumption, positively correlated with fruit and slightly with vegetable intake, and negatively with fish and seafood consumption. Finally, no clear association emerged with estimated air Se exposure.
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Tommaso
T
Filippini
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Angela
A
Ferrari
Helmholtz Zentrum München, Research Unit Analytical BioGeoChemistry, D-85764 Neuherberg, Germany.
Bernhard
B
Michalke
Helmholtz Zentrum München, Research Unit Analytical BioGeoChemistry, D-85764 Neuherberg, Germany.
Peter
P
Grill
Laboratory of Environmental Chemistry, IREN, I-42123 Reggio Emilia, Italy.
Luciano
L
Vescovi
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Chiara
C
Salvia
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Carlotta
C
Malagoli
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Marcella
M
Malavolti
Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, I-20133 Milan, Italy.
Sabina
S
Sieri
Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, I-20133 Milan, Italy.
Vittorio
V
Krogh
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Annalisa
A
Bargellini
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Antonio
A
Martino
Department of Medical, Surgical Sciences and Advanced Technologies 'G.F. Ingrassia', University of Catania, I-95123 Catania, Italy.
Margherita
M
Ferrante
CREAGEN, Environmental, Genetic and Nutritional Epidemiology Research Center, Section of Public Health, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
Marco
M
Vinceti
D015415:Biomarkers / Q000032:analysis; D003430:Cross-Sectional Studies; D004032:Diet; D019587:Dietary Supplements; D004781:Environmental Exposure; D005260:Female; D005504:Food Analysis; D005638:Fruit / Q000737:chemistry; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009262:Nails / Q000737:chemistry*; D017747:Seafood / Q000032:analysis; D012643:Selenium / Q000032:analysis* / Q000097:blood; D018036:Selenium Compounds / Q000032:analysis / Q000097:blood; D017279:Selenocysteine / Q000032:analysis; D051140:Selenoproteins / Q000032:analysis; D013054:Spectrophotometry, Atomic; D014675:Vegetables / Q000737:chemistry
D015415:Biomarkers; D018036:Selenium Compounds; D051140:Selenoproteins; D017279:Selenocysteine; D012643:Selenium