[Parental education to reduce blood lead levels in children with mild and moderate lead poisoning: a randomized controlled study].

Objective: To evaluate the effectiveness of parental education on reducing lead exposure of children by examining the changes in blood lead levels of children whose parents receiving or not receiving educational intervention.

Methods: Two hundred children with confirmed blood lead levels beyond 100 microg/L were selected. They were randomized into two groups, 107 children in study group and 93 in control. At the beginning of the study, parents of both study and control groups were called for interview to complete KABP questionnaire and lead study questionnaire. The study group was provided with interventional measures while control group was not contacted until the end of study. Intervention of parental education was undertaken by means of a TV program, a set of slides and a brochure, and focused on the questions regarding harmful effects of lead poisoning, the sources of environmental lead and prevention of this preventable disease. Tests for blood lead level were repeated for both study and control groups 3 months after the determination of the initial blood lead level.

Results: All the relevant knowledge of health effect, lead sources and prevention of childhood lead poisoning of participating parents of study group were improved significantly (chi(2) = 14.06, 13.07, 10.08, 28.26, P < 0.01) after educational intervention while parents control group also were significantly improved in the sub-catalogs of concept and prevention (chi(2) = 7.69, 8.64, P < 0.01), but not the health effect and sources of childhood lead poisoning. Children and parents' behavior in study group was improved accordingly and significantly. Less children ate popcorn (chi(2) = 4.08, P < 0.05), less children drank tap-water in the morning (chi(2) = 23.04, P < 0.01), more kids washed their hands before eating (chi(2) = 5.82, P < 0.05), less kids played on road side (chi(2) = 9.60, P < 0.01), and more parents changed their coat or took shower or washed hands before going home after work (chi(2) = 4.00, P < 0.05). But in the control group only the number of kids playing on road side was decreased significantly (chi(2) = 9.60, P < 0.01). A general decline in blood lead levels was detected in both groups with statistical significance at P < 0.01. However, the decrease in blood lead levels was more remarkable in the study group. There was average reduction of 55 microg/L (35%) in blood lead levels for study group (t = 4.979, P < 0.01) and an almost 33 microg/L (20%) for control (t = 3.398, P < 0.01). The reduction in blood lead level was 22 microg/L greater in study group (t = 3.531, P < 0.01). The study also showed that the effectiveness of the educational interventions depended upon various aspects. Fourteen variables were included in the stepwise multiple regression equation of blood lead level changes. Such as parents' occupational exposure to lead, the improvement of knowledge about prevention of childhood lead poisoning, the chang of habit of snacks intake, parents' education levels, the change of attitude of parents for the childhood lead poisoning, etc.

Conclusion: Educating parents is proved to be an effective approach for children with mild and moderate lead poisoning.