Analysis of lead, arsenic and calcium content in the hair of children with autism spectrum disorder

Abstract

Background: Explanation of the pathogenesis and treatment of autism spectrum disorders (ASD) is one of the most significant challenges for scientists today. It is believed that a major pathogenetic factor of this condition is epigenetic changes caused by environmental factors, including toxic metals (cadmium (Cd), lead (Pb), mercury (Hg), aluminium (Al), and arsenic (As)). The nervous system may also be affected by deficiencies of both micro-and macroelements (e.g. calcium (Ca), zinc (Zn)). The aim of the study was to analyze the concentrations of Pb, As, and Ca in the hair of children with ASD and a control group. Methods: The materials for the study comprised hair samples collected from 30 children diagnosed with ASD (case group) and 30 children randomly selected from the general population of Bialystok and surrounding region (control group). Concentrations of Pb, As, and Ca were tested with electron microscopy scanning method. Next, the content of the analyzed elements in the hair was assessed as well as their impact on autism development in the children and the mutual interactions between them. The obtained results were statistically analyzed with Statistica PL 12.5., using the Mann-Whitney U test, and Spearman correlation coefficient. Results: Mean Ca level in the hair of the case group was lower than the mean level of this element in the control group. Mean As and Pb concentration in the hair of children with ASD was statistically significantly higher than the mean concentration of this element in the hair of children without neurological disorders. Statistically insignificant weak positive correlations between Ca and As content and negative between Ca and Pb in the hair of children from the case group were noted. Also, statistically significant mean positive correlations between Pb and As were observed. Conclusions: In this small study, according to the observations, children diagnosed with ASD suffer from Ca deficiency and toxic metal overload (As and Pb). These abnormalities may play the main role, as an environmental factor, in the pathogenesis of the analyzed disorder.

Combining in vitro assays and mathematical modelling to study developmental neurotoxicity induced by chemical mixtures

“…Lead overload has been associated with the risk of ASD [ 120 ] and it is known to induce both micro- and astro-gliosis in the brain, triggering the production of pro-inflammatory cytokines [ 121 ]. Chronic Lead exposure has been shown to increase the percentage of astrocytes in the spinal cord of rats [ 122 ], and to induce microgliosis and astrogliosis in the hippocampus of young mice via activation of TLR4-MyD88-NFκB signalling pathways [ 123 ].…”

Oxidative stress indices in ASD children in Sub-Sahara Africa

“…As it has been previously reported, Zn has been associated with Cu absorption in the intestine; unfortunately, presence of malnutrition and/or malabsorption was not investigated in this study. Hence, it has been proposed that the plasma Zn/serum Cu ratio may be used as a rapid method of determining the functional state of the metallothionein system [26] and by inference the capability of the system to neutralize the toxic effects of heavy metals.…”

(Ascorb)ing Pb Neurotoxicity in the Developing Brain

“…The incidence of autism spectrum disorders (ASD) in children is also often associated with early-life Pb exposure and elevations in BLLs [ 28 , 58 , 99 ]. In fact, the degree of autism severity may strongly correlate with Pb levels in hair and nail samples [ 100 ].…”