Lead is highly toxic to human body especially to children and pediatric lead poisoning has been a public health problem not only in the developing countries, but also in the developed countries. Many studies have been conducted to investigate blood lead levels (BLL) of children of those countries. The mean BLL of Japanese children was among the lowest levels in the industrialized world in the early 1990's and also in the early 2000's according to our study. Fortunately the BLL of children and adults have been decreasing steadily in many countries during these two decades.
Recent studies have revealed that even low-level lead exposure (BLL less than 10μg/dl) might adversely affect growth and intellectual development of children, and it is considered now that there does not exist the safe level of blood lead.
Several studies have suggested that passive smoking causes increase of BLL of children, therefore, children should be protected from cigarette smoke for the purpose of avoiding the risk of lead exposure.