1. Geier DA, King PG, Sykes LK, Geier MR. {{A comprehensive review of mercury provoked autism}}. {Indian J Med Res};2008 (Oct);128(4):383-411.
Emerging evidence supports the theory that some autism spectrum disorders (ASDs) may result from a combination of genetic/biochemical susceptibility, specifically a reduced ability to excrete mercury (Hg), and exposure to Hg at critical developmental periods. Elemental/inorganic Hg is released into the air/water where it becomes methylated and accumulates in animal tissues. The US population is primarily exposed to methyl-Hg by fish consumption. In addition, many pharmaceuticals have been, and some continue to be, a ubiquitous source of danger because they contain mercurials. Mercurials may be found in drugs for the eye, ear, nose, throat, and skin; in bleaching creams; as preservatives in cosmetics, tooth pastes, lens solutions, vaccines, allergy test and immunotherapy solutions; in antiseptics, disinfectants, and contraceptives; in fungicides and herbicides; in dental fillings and thermometers; and many other products. Hg has been found to cause immune, sensory, neurological, motor, and behavioural dysfunctions similar to traits defining/associated with ASDs, and that these similarities extend to neuroanatomy, neurotransmitters, and biochemistry. Furthermore, a review of molecular mechanisms indicates that Hg exposure can induce death, disorganization and/or damage to selected neurons in the brain similar to that seen in recent ASD brain pathology studies, and this alteration may likely produce the symptoms by which ASDs are diagnosed. Finally, a review of treatments suggests that ASD patients who undergo protocols to reduce Hg and/or its effects show significant clinical improvements in some cases. In conclusion, the overwhelming preponderance of the evidence favours acceptance that Hg exposure is capable of causing some ASDs.
2. Mandell DS, Wiggins LS, Carpenter LA, Daniels J, Diguiseppi C, Durkin MS, Giarelli E, Morrier MJ, Nicholas JS, Pinto-Martin JA, Shattuck PT, Thomas KC, Yeargin-Allsopp M, Kirby RS. {{Racial/Ethnic Disparities in the Identification of Children With Autism Spectrum Disorders}}. {Am J Public Health};2008 (Dec 23)
Objectives. We sought to examine racial and ethnic disparities in the recognition of autism spectrum disorders (ASDs). Methods. Within a multisite network, 2568 children aged 8 years were identified as meeting surveillance criteria for ASD through abstraction of evaluation records from multiple sources. Through logistic regression with random effects for site, we estimated the association between race/ethnicity and documented ASD, adjusting for gender, IQ, birthweight, and maternal education. Results. Fifty-eight percent of children had a documented autism spectrum disorder. In adjusted analyses, children who were Black (odds ratio [OR]=0.79; 95% confidence interval [CI]=0.64, 0.96), Hispanic (OR=0.76; CI=0.56, 0.99), or of other race/ethnicity (OR=0.65; CI=0.43, 0.97) were less likely than were White children to have a documented ASD. This disparity persisted for Black children, regardless of IQ, and was concentrated for children of other ethnicities when IQ was lower than 70. Conclusions. For some children with ASD, the presence of intellectual disability may affect professionals’ further assessment of developmental delay. Our findings suggest the need for continued professional education related to the heterogeneity of the presentation of ASD.
3. Skuse D, Mandy W, Steer C, Miller L, Goodman R, Lawrence K, Emond A, Golding J. {{Social Communication Competence and Functional Adaptation in a General Population of Children: Preliminary Evidence for Sex-by-Verbal IQ Differential Risk}}. {J Am Acad Child Adolesc Psychiatry};2008 (Dec 20)
OBJECTIVE:: The proportion of schoolchildren with mild social communicative deficits far exceeds the number diagnosed with an autistic spectrum disorder (ASD). We aimed to ascertain both the population distribution of such deficits and their association with functional adaptation and cognitive ability in middle childhood. METHOD:: The parent-report Social and Communication Disorders Checklist was administered to participants (n = 8,094) in the Avon Longitudinal Study of Parents and Children. We correlated impairment severity with independent clinical diagnoses of ASD, cognitive abilities, and teacher-rated maladaptive behavior. RESULTS:: Social and Communication Disorders Checklist scores were continuously distributed in the general population; boys had mean scores 30% higher than girls. Social communicative deficits were associated with functional impairment at school, especially in domains of hyperactivity and conduct disorders. A sex-by-verbal IQ interaction effect occurred: verbal IQ was protective against social communication impairments across the range of abilities in female subjects only. In male subjects, this protective effect did not exist for those with above-average verbal IQ. CONCLUSIONS:: Social communicative deficits are of prognostic significance, in terms of behavioral adjustment at school, for boys and girls. Their high general population prevalence emphasizes the importance of measuring such traits among clinically referred children who do not meet diagnostic ASD criteria. Above-average verbal IQ seems to confer protection against social communication impairments in female subjects but not in male subjects.
