The big danger of lead poisoning
Lead in water is dreadful. But old lead paint is the greater danger to children today
Concern about what lead does to our children is very welcome. Because of the highly publicized events in Flint, Mich., residents of Pittsburgh and other cities are now demanding action. We strongly support decreasing the lead burden of our children but believe that clear thinking about how best to do so is needed. We also are concerned that the hyperbole used to galvanize action on lead is itself causing harm to children.
There are many sources of lead. The disgraceful episode in Flint has led to a welcome focus on lead in drinking water, primarily due to old leaded pipes. A long-standing, more localized issue in cities like Pittsburgh is that of lead paint inside homes built before the mid-1970s. Both need to be addressed, but which should be emphasized is now under debate.
Insight into why lead paint still represents the greater hazard comes from review of the health goals established every decade by the U.S. Centers for Disease Control and Prevention. One of the two lead-related Healthy People 2020 goals is that no child should have a blood lead level above 10 micrograms per deciliter. This is the previous CDC “level of concern” based on scientific studies, including the groundbreaking work of Herbert Needleman of the University of Pittsburgh, showing that low blood lead levels affect the growing brain. This resulted in the phasing out of lead from gasoline in 1970 when the average child’s blood lead level in the United States was 16, about five times higher than it is today.
In 2013 the CDC dropped the level further to 5, recognizing the subtle effects of lead on the growing brain. But 5 micrograms per deciliter of blood is now called a “reference level,” chosen because it was the level observed in 2.5 percent of the children under age 6 in a national survey. Exceedances of this level of 5 have received headlines in Flint and now in Pittsburgh. But exceeding the Healthy People 2020 goal of 10 has not been found in Flint, or in Allegheny County, to be based solely on drinking water. There is only so much water a child can drink — but an almost unlimited amount of paint chips that can be stuffed into a toddler’s mouth. Not surprisingly, a child can get truly dangerous levels of body lead due to flaking lead paint, even higher than the 45 micrograms per deciliter at which the CDC recommends considering medical treatment with drugs that remove lead from the body.
The second Healthy People 2020 goal related to lead is the elimination of social and racial differences in blood lead levels. For Allegheny County and most of the U.S., it is racial minorities and the poor living in older, badly maintained, rental housing that have the highest childhood blood lead levels. Meeting the goal of eliminating social and racial differences in blood lead requires a focus on paint.
Last summer, during daily media coverage about Flint, a group of undergraduate students were told to imagine they were each the decision-maker in a future hiring process in which learning on the job was an important criterion. The majority said it would negatively affect their decision if a candidate were a 2016 graduate from Flint high school. They were wrong. Their response was understandable in view of stories about irremediable brain damage, toxic death and similar overstatements of what was happening to the children of Flint.
President Barack Obama recognized this issue. When speaking in Flint he said that he did not want to have “stigma” about problems for the rest of their lives established in the minds of Flint’s kids. Unfortunately, we can find no example of Mr. Obama’s point about the negative impact of identifying children as brain-damaged in any of the extensive media coverage of his speech. Particularly problematic is that children tend to internalize expectations of others about their learning abilities.
Increased funding for removing lead sources from both paint and water is needed. Unfunded mandates from politicians to do more with less will not help. Heightened surveillance of children, as requested by Karen Hacker, director of the Allegheny County Health Department, is of particular importance to better follow how we are doing and to detect those with truly dangerous lead levels, which may occur from other sources as well. But children today should not be discouraged by being told that they are permanently brain-damaged by adults who, as children, almost certainly had far greater blood lead levels.
A long-standing, more localized issue in cities like Pittsburgh is that of lead paint inside homes built before the mid1970s.