A picture puzzle in small pieces. During my medical training, my team encountered a case of a child with developmental delays. Not unusual, but the child was referred to the clinic because of elevated blood lead concentrations. Children are screened for lead exposure during their first year of life (in Massachusetts, between 9-12 months of age). It was during this routine check-up that increased levels of lead were discovered. And this could explain the developmental delay.
However, the curious part was that no source of lead exposure could be found initially. The house did not contain lead paint or lead-glazed ceramics, or toys containing lead. The water coming into the home was lead-free, and so were the pipes. So how did this child get lead poisoning? It turns out that the water used to make the baby formula was boiled in an antique tea kettle. The kettle was lined with lead. Inadvertently lead had been part of the baby’s diet for months. Lead is a highly toxic heavy metal that can cause serious health problems, especially in children. Its discovery in municipal water supplies frequently makes the news, and I have used it as a poison in my Dr. Lily Robinson novels.
Lead poisoning causes severe neurological (both brain and peripheral nervous system) impairment and kidney, liver, and bone damage. Children are especially vulnerable as these organs are still developing, and lead accumulates in the body since it is primarily deposited in the bones. In addition, children tend to put their hands and other objects in their mouths, and some will eat paint chips around window sills or other woodwork. Lead-based paint was one of the most common sources of lead exposure. Although it has been banned in the United States since 1978, it can still be found in many older homes and apartments. Deteriorating or disturbed lead-based paint can release lead dust and particles into the air that can be easily ingested or inhaled. This is particularly so during renovations or repairs, and both children and adults can be exposed to lead dust. Those who work in lead abatement need to take special precautions to avoid self-contamination. While leaded gas was banned in the U.S. in 1990, lead deposited in soil remains a reservoir, thus able to remobilize into the atmosphere. Other lead sources can be found in some batteries and older plumbing.
Symptoms of lead poisoning occur over time as lead accumulates in the body. In addition to developmental delay and learning problems, children may complain of abdominal upset (loss of appetite, vomiting, constipation), resulting in weight loss. Adults may have similar complaints of abdominal pain, as well as joint and muscle pain, high blood pressure, and headache.
A simple blood test can determine if lead is present in the body and, if so, at what concentration. While there is no safe concentration, 5 mcg/dL is used to determine whether an unsafe lead level is present. Treatment should be considered at concentrations of 45 mcg/dL or higher. Treatment involves chelation therapy, where the medication is given orally and binds with the lead, which can then be excreted in the urine. Alternatively, EDTA chelation therapy, given by injection, can accomplish the same goal.
If lead poisoning is identified, it is paramount to determine the source. Whether it’s water flowing through lead pipes, pottery with lead glazes, and/or exposure from work or hobbies, the elimination of the heavy metal is critical. A picture puzzle, like a beautiful stained glass window, requires lead solder between the pieces of glass. What holds the image together should not ultimately undo the art maker.