Long-term effect of dust control on blood lead concentrations

Dust control is recommended to prevent children's exposure to residential lead hazards, but the long-term effect of dust control on children's exposure to environmental lead is unknown.

To determine the effect of dust control on children's exposure to lead, as measured by blood lead concentration at 48 months of age.

A randomized, controlled trial. Setting. Rochester, New York.

A total of 275 urban children were randomized at 6 months of age; 189 (69%) were available for the 48-month follow-up blood test. Intervention. Children and their families were randomly assigned to an intervention group that received cleaning equipment and up to 8 visits by a trained lead hazard control advisor or to a control group. The intervention was terminated when the children were 24 months of age.

Geometric mean blood lead concentration and prevalence of elevated blood lead concentration (ie, >/=10 microg/dL, >/=15 microg/dL, and >/=20 microg/dL), by group assignment.

For children with 48-month blood tests, baseline geometric mean blood lead concentrations were 2.8 microg/dL (95% confidence interval [CI]: 2.6, 3.0); there were no significant differences in baseline characteristics or lead exposure by group assignment. At 48 months of age, the geometric mean blood lead was 5.9 microg/dL (95% CI: 5.3, 6.7) for the intervention group and 6.1 microg/dL (95% CI: 5.5,6.9) for the control group. The percentage of children with a 48-month blood lead >/=10 microg/dL, >/=15 microg/dL, and >/=20 microg/dL was 19% versus 19%, 2% versus 9%, and 1% versus 2% in the intervention and control groups, respectively.

We conclude that dust control, as performed by families and in the absence of lead hazard controls to reduce ongoing contamination from lead-based paint, was not effective in preventing children's exposure to residential lead hazards.