Deficits in cognitive function and achievement in Mexican first-graders with low blood lead concentrations

Caracterização das alterações de linguagem em crianças com histórico de intoxicação por chumbo

“…When considering memory, we also have to consider a cognitive function tightly related to language, negatively affected by the lead intoxication, as well as other cognitive functions, even when it is below 10 g/dl (3,8,9). The findings of the present study agree with the ones mentioned above, once it was found a considerable amount of damage in this function.…”

“…Some authors suggest that even lower lead levels than the accepted by the World Health Organization present risk for disorders in the skills mentioned above, indicating that a security margin does not exist for lead exposure (3,(7)(8)(9). On the other hand, certain studies do not find correlation between the blood lead level and the neuropsychological dysfunctions presented by contaminated children, evidencing that genetic and environmental factors may aggravate the hindering effects of the lead in the neural development, making some children more vulnerable to the neurotoxic effects of the metal, or yet, despite having a significant influence in children's development, other environmental factors may be even stronger (10)(11)(12).…”

Characterizing Golden Eagle Risk to Lead and Anticoagulant Rodenticide Exposure: A Review

“…Chiodo et al (2004) indicated that data on maternal and child nutritional status, including iron deficiency, were not available so that their possible influence on the association between lead neurobehavioral outcomes could not be controlled. Kordas et al (2006) studied the association between lead and cognitive function in 594 first-grade children exposed to lead from a metal foundry in Torreón, Mexico. Their ages ranged from 6.2 to 8.5 years and their mean PbB was 11.4 μg/dL (SD±6.1 μg/dL).…”

“…The nervous system is a sensitive target for lead toxicity in humans (for representative references, see Chronic-Duration Exposure and Cancer, above) and in animals. Of special concern are the results of recent studies that have reported neurobehavioral deficits in children associated with PbBs <10 μg/dL and an apparent lack of threshold down to even the lowest PbBs recorded in these studies (Bellinger and Needleman 2003;Canfield et al 2003;Chiodo et al 2004;Kordas et al 2006;Lanphear et al 2000aLanphear et al , 2005Téllez-Rojo et al 2006). Some of these studies found that the slope of the dose-response is steeper at lower PbBs than at higher PbBs; that is, the effects of lead on cognitive function is greater in children with lower PbB than in children with higher PbB.…”

“…Children are more sensitive than adults to lead toxicity and a great number of studies conducted in the last decades have focused on the evaluation of neurobehavioral effects of lead in children that have been associated with relative low blood lead levels (i.e., <10 μg/dL) (Bellinger and Needleman 2003;Canfield et al 2003;Chiodo et al 2004;Kordas et al 2006;Lanphear et al 2000aLanphear et al , 2005Téllez-Rojo et al 2006). Although the preponderance of the evidence suggests that lead exposure in children is associated with small decrements in intelligence, there are studies that have not found such an association.…”