Primary prevention of childhood lead exposure: A randomized trial of dust control.

BACKGROUND

Dust control is recommended as one of the primary strategies to prevent or control children's exposure to residential lead hazards, but the effect of dust control on children's blood lead levels is poorly understood.

OBJECTIVE

To determine the effectiveness of dust control in preventing children's exposure to lead, as measured by blood lead levels, during their peak age of susceptibility.

DESIGN

A randomized, controlled trial.

SETTING

Rochester, NY.

PARTICIPANTS

A total of 275 urban children were randomized at 6 months of age, of whom 246 (90%) were available for the 24-month-old follow-up visit.

INTERVENTIONS

Children and their families were randomly assigned to an intervention group (n = 140), which received cleaning equipment and up to eight visits by a dust control advisor, or a control group (n = 135).

OUTCOME MEASURES

Geometric mean blood lead levels and prevalence of elevated blood lead levels (ie, >10 microg/dL, 15 microg/dL, and 20 microg/dL).

RESULTS

At baseline, children's geometric mean blood lead levels were 2.9 microg/dL (95% confidence interval [CI] = 2.7, 3.1); there were no significant differences in characteristics or lead exposure by group assignment, with the exception of water lead levels. For children in the intervention group, the mean number of visits by a dust control advisor during the 18-month study period was 6.2; 51 (36%) had 4 to 7 visits, and 69 (49%) had 8 visits. At 24 months of age, the geometric mean blood lead was 7.3 microg/dL (95% CI = 6.6, 8.2) for the intervention group and 7.8 microg/dL (95% CI = 6.9, 8. 7) for the control group. The percentage of children with a 24-month blood lead >/=10 microg/dL, >/=15 microg/dL, and >/=20 microg/dL was 31% versus 36%, 12% versus 14%, and 5% versus 7% in the intervention and control groups, respectively.

CONCLUSIONS

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, is not effective in the primary prevention of childhood lead exposure.