The effect of lead exposure on IQ test scores in children under 12 years: a systematic review and meta-analysis of case-control studies

Abstract

An inevitable exposure to the toxic heavy metal such as lead in our environmental can have irreversible effects on children’s mental performance.In this study, 3316 children in 8 case-control studies were selected for review. The case group was exposed to a concentration of lead above 10 μg/dL, and the control group was exposed to a concentration of less than 10 μg/dL, but the duration of exposure was different among studies, and the subgroup analysis was performed based on this variable.In the subgroup with duration of exposure less than the average of 4.5 years, the difference of IQ test score between two groups was significant (MD = −3.53) (P-value <0.05). Also, in the subgroup with more than 4.5 years of duration, the difference of IQ test score was significant (MD = −22.63) (P-value < 0.001).This study demonstrates that the concentration and duration of lead exposure have a large effect on mental function in children.

Blood lead level and cognitive performance in Ukrainian schoolchildren

“…Including the systematic review and meta-analysis of case-control studies were provided by investigations from different countries over the world. This study also demonstrated that the concentration of lead exposure had a large effect on mental function in children under 12 years [3].…”

“…Especially adverse effects of lead on the mental function. The new systematic review and meta-analysis of casecontrol studies demonstrate the large effect of lead exposure on IQ test scores in children under 12 years [3]. The World Health Organization estimate that lead exposure causes 30% of the global burden of idiopathic intellectual disability [4].…”

The Effect of Giving Celery Extract on Testicular Function of Wistar White Rats Exposed to Lead Acetate

“…Lead phosphate is absorbed by the brain, liver, spleen, kidneys, and spinal cord and then redistributed to other body parts sensitive to its effects (Balali-Mood et al, 2021). The body's lead contamination can damage IQ (Heidari et al, 2022;Hou et al, 2013;Levinschwartz et al, 2020;Schwartz, 1994). Children infected with up to 10 micrograms of Pb can become idiots.…”

Assessment of the Concentration of 51 Elements in the Liver and in Various Parts of the Human Brain—Profiling of the Mineral Status

“…Some elements are toxic at very low concentrations, e.g., Pb, Cd, Hg, As, Mo, Be, Ga, Sb, radon (Rn), Bi, and polonium (Po). It has been documented that an increase in environmental Pb is directly proportional to a decrease in IQ in children [ 18 ]. The adverse effects of overexposure to metals and metalloids such as Al, Sb, As, Ba, Be, Bi, B, Cd, Cr, Co, Cu, Ga, indium (In), Ge, gold (Au), Fe, Pb, Li, Mn, Hg, Mo, Ni, niobium (Nb), tantalum (Ta), platinum (Pt), palladium (Pd), iridium (Ir), Rh, osmium (Os), ruthenium (Ru), yttrium (Y), lanthanum (La), Se, Ag, tellurium (Te), thallium (Tl), Sn, Ti, tungsten (W), V, Zn, Zr and hafnium (Hf) are well known in occupational medicine.…”