Low Levels of Lead in the Blood and the Occurrence of Gout FREE

Lead is a naturally occurring element that has been used in many ways, including in building construction, paints, and batteries. Exposure to high levels of lead may cause health problems, such as damage to the nervous system. National standards aim to reduce lead exposure so that blood levels of lead remain in a range considered to be safe. Whether lead-related health problems can be completely eliminated with levels in this target range remains controversial.

Gout is a disease involving the collection of crystal-like particles in joints that can cause severe pain and destruction of the joint. These crystals are formed by uric acid from the blood. Elevated blood levels of lead are known to be associated with increases in both uric acid and the occurrence of gout.

To find out whether blood levels of lead within the range currently considered to be acceptable are associated with an increased prevalence of gout.

6153 volunteers. People with advanced kidney disease (including those requiring dialysis) were not included in the study because kidney disease is associated with increases in uric acid and gout.

Volunteers completed questionnaires about their medical problems, and blood samples were collected so that lead levels could be measured. Blood levels of the elements cadmium and mercury were also measured for comparison. Some volunteers completed question-naires about their diets because certain foods may contain chemicals that are used in the production of uric acid.

Most of the participants had blood lead levels that were within the national target levels. Still, increasing blood levels of lead within this range were associated with both increasing blood levels of uric acid and a reported history of gout. This association was seen even after the researchers accounted for other medical problems, as well as differences in the volunteers' diets. In contrast, blood levels of cadmium and mercury were not associated with a history of gout.

The researchers could not examine medical records to definitively confirm whether the participants had a history of gout. The study relied on single measurements of blood lead level, which might not accurately reflect a person's exposure to lead over time. This type of study cannot tell whether the lead in the participants' blood actually caused gout.

Blood levels of lead that are currently within the acceptable range might still be associated with health problems, such as gout. More research is required to see whether the “low” levels of lead seen can cause gout and whether efforts to further reduce them are beneficial.