The current EPA reference dose (0.1 μg/kg body wei- ght-day) has been shown to provide a concentration in human blood of 5.8 μg/L [11]. Recurring levels above this value is believed to cause harm, in particular to the developing fetus. Most of the blood samples collected in this study registered lower than that threshold, as evident from Figure 1, but some fish-eating subjects had unusu-ally high values. For those individuals quick corrective actions might be needed, highlighting the advantage of the described method.