The objective of this study is to establish reference values in the general population from a Beckman Coulter DxI chemiluminescence assay.

Indeed, the lack of harmonization of the methods of the dosage remains a major difficulty to optimize the management of patients with thyroid disease.

This supplier has recently optimized its dosing kit according to the 3rd international standard of the WHO (IRB 81/565) for the TSH (Thyroid Stimulating Hormon).

It is necessary to carry out a study of the distribution of the values of this TSH within our metropolitan population. The current data proposed by the supplier come from a study of a North American population.

investigators propose to define usual values for thyroid status markers (TSH, FT4 [free thyroxine], FT3 [free triiodothyroxine]) from healthy EFS (French Blood Establishment) donors who meet the standard exclusion criteria for this type of study.

Inclusion Criteria:

• Donors (18-70 years old) volunteers at EFS

Exclusion Criteria:

• pregnancy,
• known antecedents of thyroid diseases (goiter, nodule, hypo or hyperthyroidism),
• current antithyroid treatment (neomercazole [Thyrozol(r)], levothyroxyn LT4 [levothyrox(r)], ...),
• cardiac treatment with amiodarone (cordarone(r)),
• injection of iodinated contrast medium less than 1 month old