Lead poisoning can be devastating at any age, but is particularly destructive in very young children due to its effects on the developing brain. The events in Flint, Michigan have highlighted this long-standing issue of national importance.
Lead is a naturally occurring heavy metal that is also found in older paint (pre-dating 1978), some pipes, folk remedies from various countries (India, China, Thailand, Latin America and elsewhere), soil, some ceramics, environmental dust, water and some traditional cosmetics (“kohl,” an eyeliner). It can also be found in products used in leisure activities such as stained glass window making and hunting (use of lead containing pellets).
Lead, which accumulates in tissues, can give a variety of symptoms in children, including developmental delays, irritability, weight loss, abdominal pain, constipation, fatigue, and hearing loss. Adults can also present with a number of signs and symptoms (notably hypertension, muscle pains, abdominal pains, constipation, headache, mood swings, and declining mental status). Initial lead exposure in both children and adults may also be asymptomatic (no symptoms at all). Physicians must have a high level of suspicion, especially when patients present with a baffling array of seemingly minor and unrelated symptoms.
Treatment of lead poisoning depends on the blood lead levels. At lower levels, it is critical to locate and eliminate the source of exposure. Since lead can be present in many sources in the environment, some detective work may be required. Paint in older housing (prior to 1978) must always be considered, as well as older furniture, toys, pipes, ceramics and traditional remedies and cosmetics. Caregiver education is critical to insure elimination of all sources of lead.
For very elevated blood lead levels (BLL), (i.e. over 45 micrograms/dl), chelation treatments (whether oral or with an EDTA) may be considered, although these must be strictly supervised by a physician. For all elevated levels, regular monitoring of BLL should occur that will document a progressive decrease. Special neurological testing may be required, and it is important to remember that developmental surveillance should continue well after diagnosis occurs since the effects of lead poisoning last for years.
Although considerable research and debate has occurred, the scientific consensus is that dietary supplementation with iron, vitamin C and calcium is not required if normal adequate intake is assured and previous deficiencies do not exist. For environmental sources, simple measures like hand washing, wet mopping floors, leaving shoes at the door, avoiding direct soil content, and using cold tap water for drinking and cooking can help in reducing exposure. Any lead related to hobbies (stained glass, use of lead pellets for hunting, furniture restoration, car batteries, and others) should be identified and eliminated. To reassure the public, water systems in Louisiana are regularly tested by the Department of Health and Hospitals, Office of Public Health, and elevated levels are aggressively addressed.
Fortunately, pediatricians screen for blood lead levels (BLL) during routine well-child exams, although there are some practitioner variations in when and how often this occurs. Blood lead surveillance is tracked nationally since at least 1997, and the results have shown a dramatic reduction in the percentage of children with confirmed elevated BLL above 10 micrograms/deciliter from 7.61% (1997) to 0.53% (2014). This has also been true in Louisiana, where the percent of children tested with elevated BLL fell from 2.38% (1998) to 0.67% (2014) out of over 375,000 infants and children tested. There is some discussion recently about reducing the acceptable thresholds.
Despite these dramatic decreases from previous decades, we still need to have broad public awareness of this problem which still remains an avoidable threat to infants and adults. It’s time for us all to get the lead out!