Environmental exposure to trace elements and risk of amyotrophic lateral sclerosis: a population-based case-control study.
We analyzed the association between the environmental exposure to trace elements and the risk of sporadic amyotrophic lateral sclerosis (ALS) in a population-based case-control study in the Emilia-Romagna region in northern Italy. We evaluated exposure to selected trace elements by measuring toenail concentrations of the same by means of inductively coupled plasma optical spectrometry and instrumental neutron activation analysis. The final number enrolled in the study was 22 patients and 40 controls. Disease progression, assessed through a clinical score, was generally unassociated with toenail trace element levels, with the exception of an inverse relation with zinc and selenium content and a direct correlation with copper concentration. In logistic regression analysis, we found no evidence of an association between ALS risk and toenail content of cadmium, lead, copper, zinc, manganese, selenium, chromium, cobalt, iron, and aluminum. This investigation does not suggest a major role in sporadic ALS etiology of environmental exposure to these trace elements, though results for zinc, selenium, and copper should be evaluated with caution due to the potential limitations of toenails as biomarkers of chronic exposure in patients.
Dipartmento di Scienze Igienistiche, Microbiologiche e Biostatistiche, Università di Modena e Reggio Emilia, Italy. bergomi@unimo.it
Margherita
M
Bergomi
Marco
M
Vinceti
Grazia
G
Nacci
Vladimiro
V
Pietrini
Peter
P
Brätter
Dorothea
D
Alber
Angela
A
Ferrari
Luciano
L
Vescovi
Donata
D
Guidetti
Patrizia
P
Sola
Susanna
S
Malagu
Chiara
C
Aramini
Gianfranco
G
Vivoli
D000690:Amyotrophic Lateral Sclerosis / Q000453:epidemiology / Q000209:etiology*; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D018450:Disease Progression; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D009262:Nails / Q000737:chemistry; D012044:Regression Analysis; D014131:Trace Elements / Q000009:adverse effects*
D015415:Biomarkers; D014131:Trace Elements