Content of arsenic, cadmium and lead in food, tobacco leaves, pasture and weeds from the endemic area. Horizontal lines within the boxes represent the median values. The ends of the solid lines extending on either side of the boxes represent the minimum and the maximum. The dark dots are outliers ; defined as being more than 1.5 interquartile ranges away from the box. The interquartile range is the distance between the upper part of the box and the lower part of the box. (The cadmium and lead content in certain food items exceeded the maximum stipulated reference valuea). a The maximum levels of cadmium permitted by the Codex Alimentarius for vegetables is 0.2 mg/kg [22, 23] and by the Commission of the European Communities is 0.05 mg/kg . The maximum concentration of cadmium stipulated for certain types of fish by the Commission of the European Communities is 0.05 mg/kg . The maximum concentration of lead stipulated for vegetables by the Commission of the European communities is 0.10 mg/kg .