Cognitive Deficits Associated with Blood Lead Concentrations <10 microg/dL in US Children and Adolescents

Abstract

Deficits in cognitive and academic skills associated with lead exposure occur at blood lead concentrations lower than 5 microg/dL.

Environmental lead contamination in Miami inner-city area

“…The NRC offered evidence that lead at 5 g/ dl (half the official ''safe'' level ) can cause attention deficit in children and in monkeys; reduced birth weight in children; and hearing loss in children (NRC, 1993 ). At the recent Joint Meeting of the Pediatric Academic Societies and American Academy of Pediatrics in Boston, Lanphear et al (2000 ) reported that the current limit of 10 g/dl is ''inadequate to protect the children,'' and should be at least half that amount. Inverse associations were observed between blood -lead concentration and deficits in cognitive functioning and academic achievement in children at levels below 5.0 g/dl (Lanphear et al, 2000 ).…”

Lead Poisoning Among Pregnant Women in New York City: Risk Factors and Screening Practices

“…It is well documented 4,5 that lead can cross the placental barrier and produce toxic effects at BLL levels below 20 µg/dL-the case definition used here. It is expected that the incidence rate of pregnant women with would have been higher than reported if a lower case definition (say, 10 µg/dL rather than 20 µg/dL) had been employed.…”

“…First, studies show toxic effects of lead at lower and lower levels. 3,4 Second, despite overall population improvements, certain subgroups continue to be at risk for high-dose lead exposure and its toxic effects, including: occupationally exposed adults, preschool-aged children, pregnant women and their fetuses, persons who live near sites where lead has been improperly disposed, and persons who intentionally or unintentionally ingest or inhale lead-contaminated food or other products. 5 In the past quarter century, lead poisoning prevention efforts have focused primarily on controlling and monitoring exposures relevant to the first two groups: occupationally exposed adults 6,7 and young children living in homes with dust and paint chips from deteriorated leadbased paint.…”

Novel Treatment for Lead Exposure in Children with Autism

“…Moreover, the correlation of gene expression and lead levels in blood in children with autism compared to typically developing controls is different [12]. Even very low level of lead exposure in childhood may cause lifelong impairment of attention, memory and learning deficits [1,8].Meanwhile, urinary lead excretion rate in autism is deceases in compare to typically developing control group [13]. In addition, the level of lead in hair [5,7] and nail [7] of children with autism is higher than healthy children group [7].…”

“…Moreover, the correlation of gene expression and lead levels in blood in children with autism compared to typically developing controls is different [12]. Even very low level of lead exposure in childhood may cause lifelong impairment of attention, memory and learning deficits [1,8].…”