To the Editor: In their study on persons aged
50 to 70 years,1 Dr Weil and colleagues found
no association between blood mercury levels and neurobehavioral function.
We believe that some limitations in this study need to be considered.
First, as the authors note, blood mercury levels represent only recent
exposure to methylmercury. Therefore, they have not considered exposure to
other chemical forms of mercury like inorganic mercury or mercury vapor, which
are normally measured in urine. Exposure to low levels of mercury vapor has
been associated with impairment of neurobehavioral function.2
Blood Mercury Levels and Neurobehavior. JAMA. 2005;294(6):679-680. doi:10.1001/jama.294.6.679-a