Lead Exposure Linked to Risk for Dementia

A study in the Journal of Alzheimer's Disease suggests lifetime exposure to lead may be linked to dementia risk, as declining rates of exposure in North America and parts of Europe may underpin falling dementia incidence in those regions, reports United Press International . University of Toronto researchers found the mean blood lead level (BLL) in the United States was 12.8 µg/dL from 1976 to 1980, but fell to 2.8 µg/dL from 1988 to 1991 and then to 0.84 µg/dL in 2013-2014. Of particular interest to the investigators is a potential connection between lifetime lead exposure and a subtype of dementia called Limbic-predominant Age-related TDP-43 Encephalopathy (LATE). Studies imply that LATE is the cause of about 20 percent of dementia cases. To verify this linkage, the researchers recommend future studies compare BLLs in the 1990s to current Medicare records by evaluating lead levels in teeth and tibia bones when performing post-mortems of brains for dementia. "If lifetime lead exposure is found to be a major contributor to dementia, we can expect continued improvements in the incidence of dementia for many more decades as each succeeding generation had fewer years of exposure to the neurotoxin," said the University of Toronto's ZhiDi Deng.