Multi element standard analytical solutions

Collected uterine and testicular tissues, and hair samples were handled using plastic instruments with special care taken to avoid any contamination. Thawed tissues were dried in an oven at 40 o C, flushed twice with MilliQ water (Millipore, USA) to ensure the removal of blood remnants and dried again to a constant weight. All samples (hair, uterine and testicular tissues) were subjected to a complete digestion performed with suprapur 14 mol/L HNO 3 (Sigma-Aldrich, Germany) in sealed plastic tubes using an oven (80 o C). The concentration of iron in the investigated samples was determined by the fast sequential atomic absorption spectrometer SpectrAA 220 FS (Varian, Australia) equipped with HCL lamps (Varian, Australia) and a Sampling System with an Electronic Control Module SIPS-20 (Varian, Australia). Following optical conditions were applied: wavelength 248.3 nm, slit 0.2 nm, with background correction from a deuterium lamp. The calibration was performed using multi-element standard analytical solutions (Merck, Germany). A control without any tissue but containing HNO 3 was performed in order to exclude the interference of any procedural step on metal content determination -the iron content was below the limit of detection. The final results were given as ppm of Fe (mg Fe kg -1 sample).