Lead consumption of 18- to 36-month-old children as determined from duplicate diet collections: nutrient intakes, blood lead levels, and effects on growth

Objective: To determine the amount of lead ingested in food by means of duplicate diet collections, nutrient intakes, and anthropometric measurements of young children. Design: Once a month for a year, data were collected from 24-hour duplicate diets, hand wipes, a dust index, and anthropometric measurements. Quarterly, venous blood samples were obtained. Thermal ionization spectrometry by means of a lead-205 tracer was used to determine lead present in food, blood, and the hand wipes. A dust index was determined on the basis of observation of dust on surfaces in the home. Anthropometric measurements obtained were height, weight, head circumference, and mid-upper arm circumference. Subjects/setting: Subjects were 21 children, aged 18 to 36 months, who resided in homes located in an urban area with potentially high lead levels. Main outcomes measured: Lead contamination in food and on hands, and blood lead values, were determined. Statistical analysis performed: Pearson correlation coefficients were used to determine relationships between lead content in food, blood, and hand wipes and growth. Multiple regression analyses examined the effect of food types and dust lead on lead levels in food, and the effect of these variables on head circumference. Results: Mean blood levels were 0.3089+/-0.1496 micromole/L; 12 samples contained more than 0.4826 micromole/L. Total intake of lead from food was 4.95 microgram/day and ranged from 1.10 to -22.10 microgram/day. More than a fourth of the diets collected exceeded 6.00 microgram/day. Foods considered home prepared were moderately related to blood lead level, and the dust index and hand wipe lead levels were related to total food lead. Home-handled foods, canned foods, and hand-wipe lead were significant predictors of the lead content in food. A negative relationship was found between head circumference and blood lead level. Applications: Level of lead in food was directly related to hand-wipe lead. This finding underscores the need for dietitians and other health professionals to stress the importance of cleanliness in environments that are potentially lead contaminated. Appropriate hand washing and surface cleaning should be emphasized when preparing and consuming food. The inverse relationship between head circumference and blood lead levels points to the need for additional studies to validate this finding while controlling for other extraneous variables.