Adopted by Council, March, 1995
To be reviewed

Research demonstrates that lead exposure has an important and under recognized effect on the behavior of children and adolescents. As early as 1943, it was reported that children recovering from clinical lead poisoning exhibited severe attentional problems, including increased aggressive behavior, learning difficulties and school failure. More recently, attention has focused on children with otherwise "asymptomatic" lead exposure. Considerable data have documented that even relatively low lead levels (e.g. 10 µg/dl) produce significant behavioral symptoms. The following specific effects have been documented:

• Decreased attention
• Distractibility
• Impulsivity
• Inability to follow directions
• Hyperactivity
• Conduct problems
• Aggressive Behavior
• Learning difficulties
• Developmental delays
• Impaired social interaction

Lead toxicity is a very common problem. Typical sources of environmental lead include paint, water and soil. It is estimated that at least 17% of all American children have elevated blood lead levels, although rates vary across the country. While lead toxicity occurs in families at all socioeconomic levels, the rate is much higher in economically disadvantaged families.

Lead toxicity is a treatable condition. Appropriate intervention includes:

• Identification and removal of the source of lead exposure.
• Ongoing monitoring of children with lead levels above 10 µg/dl.
• Chelation for children with lead levels in excess of 35 µg/dl.

Children with elevated blood lead levels should be screened for iron and zinc deficiencies. As a preventative measure, it is recommended that all children in a family should be screened for blood levels if any one child is found to have a level in excess of 5 µg/dl.

Early detection, intervention and ongoing prevention are the best approaches to the problem of childhood lead exposure. Accordingly, the Academy recommends that child and adolescent psychiatrists include environmental lead exposure in the differential diagnosis of children exhibiting symptoms of conduct and behavior disorders, learning disabilities and attentional problems. For children who exhibit any of the signs or symptoms described above, and who are also at risk for lead exposure, the results of a recent blood lead level should be documented.

References

CDC (1991): Strategic Plan for the Elimination of Childhood Lead Poisioning. Centers for Disease Control, Department of Health and Human Services, Atlanta, GA.

Fergusson, DM; Fergusson, JE; Horwood, LJ; Kinzett, NG (1988): A longitudinal study os dentine lead levels, intelligence, school performance and behaviour. Part II Dentine lead and cognitive ability. Journal of Child Psychology and Psychiatry. 29, 7930809.

Fulton, M; Raab, G; Thomson, G; Laxen, D; Hunter, R; Hepburn, W (1987): Influence of blood lead on the ability and attainment of chlidren in Edinburgh. Lancet. 1, 1221-1226.

Needleman, HL; Gastsonis, C (1990): Low level lead exposure and the IQ of children. JAMA 2263(5), 673-678.

Needleman, HL; Schell, A; Bellinger, D; Levton, A; Allred, EN (1990): The long-tern effects of exposuure to low doses of lead in childhood: An 11-year follow-up report. New England Journal of Medicine. 322, 83-88.

Thomson, GOB, Raab, GM; Hepburn, WS; Hunter, R; Fulton, M; Laxen, DPH (1989): Blood lead levels and children's behaviour - Results from the Edinburgh lead study. Journal of Child Psychology and Psychiatry. 30, 515-528.

Needleman, HL., (1993): The Current Status of Childhood Lead Toxicity, Advances in Pediatrics, Vol. 40, 125-139.

Ruff, H; Bijur, P; Markowitz, M; Ma, Y; Rosen, J. (1993): Declining Blood Levels and Cognitive Changes, JAMA, Vol. 269, No. 13, 1641-1646.