100 µg/kg means 100 ppb or 0.100 ppm.

So for your final solution of 1 mL of 0.100 ppm you will need to add 1.0 µL of PAH standards of 100 ppm and 0.10 µL PAH standards of 1000 ppm. Because the pipetted volumes are very low, I would suggest you to prepare a intermediary dilution at 1 ppm (10 mL volumetric flask: 0.1 mL standards of 100ppm and 0.01 mL standards of 1000ppm). Then, from this intermediary solution of 1ppm you can make the final solution by pipetting 0.1mL intermediary solution and 0.90 mL of solvent.

Thank you for the fast answer, so i have to pour 1μL of each standard to make a volume of 1mL of 100ppb 4 substances (Chrysene etc) PAH. Yeah i ll make one intermediary.

Thank you again!