Optimization and validation of the methods for the total mercury and methylmercury determination in breast milk.
The objective of the work was to develop and validate methods for the total Hg and methylmercury (MeHg) in breast milk that could be further used to obtain first data on chemical contamination of French breast milk. For total Hg determination, the potential of two techniques, namely Advanced Mercury Analyzer (AMA) and ICP MS, was compared. For MeHg determination, ICP MS detection associated to a quantification by isotopic dilution was used and the potential of a preliminary separation by gas or liquid chromatography was evaluated and discussed. The optimization studies have shown that AMA for total Hg determination and HPLC - ID - ICP MS, after a preconcentration step by freeze-drying, for MeHg quantification were the most relevant methods to use for epidemiologic studies. The figures of merit for both methods were evaluated by means of accuracy profiles in terms of limits of quantification (1.82 and 1.35µg Hg/kg dry weight, corresponding to 0.22 and 0.16µg Hg/kg wet basis for total Hg and MeHg, respectively), repeatability (2-11% and 3-8% for total Hg and MeHg respectively), intermediate precision reproducibility (4-12% and 4-8% for total Hg and MeHg respectively) and trueness bias (-0.1-9% and -4-0% for total Hg and MeHg respectively). The methods were then applied to 180 breast milk samples. Total Hg concentrations ranged from <LD to 16.9µg Hg/kg wet basis (<LD to 142µg Hg/kg dry weight) and the MeHg contents from <LD to 0.43µg Hg/kg wet basis (<LD to 3.67µg Hg/kg dry weight).
UT2A, Hélioparc Pau-Pyrénées, 2 Avenue du président Angot, 64053 Pau, France. Electronic address: veronique.vacchina@univ-pau.fr.
Véronique
V
Vacchina
UT2A, Hélioparc Pau-Pyrénées, 2 Avenue du président Angot, 64053 Pau, France.
Fabienne
F
Séby
Université de Paris-Est, Anses, Laboratoire de Sécurité des Aliments, 94700 Maisons-Alfort, France.
Rachida
R
Chekri
UT2A, Hélioparc Pau-Pyrénées, 2 Avenue du président Angot, 64053 Pau, France.
Justine
J
Verdeil
UT2A, Hélioparc Pau-Pyrénées, 2 Avenue du président Angot, 64053 Pau, France.
Jean
J
Dumont
Université de Paris-Est, Anses, Laboratoire de Sécurité des Aliments, 94700 Maisons-Alfort, France.
Marion
M
Hulin
Anses, Direction de l'Evaluation des Risques, 94700 Maisons-Alfort, France.
Véronique
V
Sirot
Anses, Direction de l'Evaluation des Risques, 94700 Maisons-Alfort, France.
Jean-Luc
JL
Volatier
AP/HP, Département de Pharmacologie Clinique et Unité de Recherche Clinique (URCEST), Hôpital Saint Antoine, 75012 Paris, France; Réseau Médic-Al, Paris, France.
Raphaël
R
Serreau
AP/HP, Département de Pharmacologie Clinique et Unité de Recherche Clinique (URCEST), Hôpital Saint Antoine, 75012 Paris, France.
Alexandra
A
Rousseau
AP/HP, Département de Pharmacologie Clinique et Unité de Recherche Clinique (URCEST), Hôpital Saint Antoine, 75012 Paris, France; Université de la Sorbonne Paris 6, UPMC, Département de Pharmacologie, Paris, France.
Tabassome
T
Simon
Université de Paris-Est, Anses, Laboratoire de Sécurité des Aliments, 94700 Maisons-Alfort, France.
Thierry
T
Guérin
D002851:Chromatography, High Pressure Liquid; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D013058:Mass Spectrometry; D008628:Mercury / Q000032:analysis*; D008767:Methylmercury Compounds / Q000032:analysis*; D008895:Milk, Human / Q000737:chemistry*
D008767:Methylmercury Compounds; D008628:Mercury
AMA; Breast milk; HPLC – ID – ICP MS; Mercury; Methylmercury