DO DISTRICT children who live in well-to-do neighborhoods have high levels of lead in their blood - levels that might indicate the early stages of lead poisoning? Unfortunately, the answer depends on who is doing the talking. The city's Department of Environmental Health, for example, thinks that, in some instances, the answer might be yes. Last year, DEH officials tested children who lived in Georgetown, Burleith, Cleveland Park and Glover Park and found surprisingly high levels of lead in their bodies. Their study also indicated that youngsters who lived near streets with heavy traffic had an even higher lead level than those who lived near less busy thoroughfares.

The DEH study was widely criticized as too vague and inconclusive; the agency was urged to do a retest. But before it was started, the Department of Human Resources conducted its own testing of children from west of the park - children, it turned out, who had been included in the ealier study. DHR officials found almost no elevation in lead levels - all of the children DHR tested were just fine. The differences between the conclusions of these two reports was so startling that DHR was asked to go back and test the children again. Parents, pediatricians and members of private groups such as the D.C. Committee on Lead Elimination suspected that DHR had been less than scientific in its work. Tests to determine lead levels in the blood demand much more precision than other blood tests; minor errors can cause major changes in tests results.

DHR's retesting has raised even more questions than its original study did. Fewer than 200 of the 700 youngsters first tested have been found; minimal efforts have been made to reach the others. DHR officials have refused to provide an analysis of the findings of the original study that claimed there were no lead-level excesses. And both the Committee on Lead Elimination and the Department of Housing and Urban and Development have been refused the chance to examine the data and verify DHR's conclusions.

By and large, lead poisoning has been thought a problem in lower-income neighborhoods where lead-based paint is peeling from the walls of old and dilapidated housing. Children eating paint chips become ill, and some are permanently crippled. The incidents of lead poisoning decreased dramatically when the toxic paint was taken off the market and stripped from the walls. But none of the children tested by either the health or human-resources agencies had ever ingested lead-based paint - yet one agency (but not the other) said they had high lead levels.

Now, almost a year later, DHR still hasn't completed its retesting, and parents and pediatricians remain confused. No one knows whether there is a problem, let alone what to do about it. We think city officials should ask the Committee on Lead Elimination to step in and give some help. That organization could analyze the existing data and decide if further studies are needed. If additional testing is warranted, the committee is just the group to make sure that the retesting is done correctly. The possibility - slim as it may be - that children have excessively high levels of lead in their blood must not be treated casually; lead poisoning can be a crippling disease. It is particulary harmful to children under 6 years of age and can cause brain damage and growth retardation. City officials cannot defer this matter any longer; the lives of children are at stake.