Autism spectrum disorder prevalence and proximity to industrial facilities releasing arsenic, lead or mercury
Sci Total Environ. 2015 Dec 1;536:245-51
"Prenatal and perinatal exposures to air pollutants have been shown to adversely affect birth outcomes in offspring and may contribute to prevalence of autism spectrum disorder (ASD). For this ecologic study, we evaluated the association between ASD prevalence, at the census tract level, and proximity of tract centroids to the closest industrial facilities releasing arsenic, lead or mercury during the 1990s. We used 2000 to 2008 surveillance data from five sites of the Autism and Developmental Disabilities Monitoring (ADDM) network and 2000 census data to estimate prevalence. Multi-level negative binomial regression models were used to test associations between ASD prevalence and proximity to industrial facilities in existence from 1991 to 1999 according to the US Environmental Protection Agency Toxics Release Inventory (USEPA-TRI). Data for 2489 census tracts showed that after adjustment for demographic and socio-economic area-based characteristics, ASD prevalence was higher in census tracts located in the closest 10th percentile compared of distance to those in the furthest 50th percentile (adjusted RR=1.27, 95% CI: (1.00, 1.61), P=0.049). The findings observed in this study are suggestive of the association between urban residential proximity to industrial facilities emitting air pollutants and higher ASD prevalence."
Sorting out the spinning of autism: heavy metals and the question of incidence
Acta Neurobiol Exp (Wars) 2010;70(2): 165-76
"The various causes that have led to the increase in autism diagnosis are likely multi-faceted, and understanding the causes is one of the most important health topics today. We argue that scientific research does not support rejecting the link between the neurodevelopmental disorder of autism and toxic exposures."
Common Pesticides Linked to Autism: The Role of an Organic Diet and Sulforaphane
"A study out of the University of North Carolina Medical School found that pesticides, including a new class of fungicides, caused transcription (genetic) changes in the brain consistent with brain samples of individuals with autism, advanced age and neurodegenerative diseases such as Alzheimer’s disease and Huntington’s disease." Here is a link to the UNC study.
Chemicals banned decades ago linked to increased autism risk today
Chemicals banned decades ago linked to increased autism risk today
"Chemicals used in certain pesticides and as insulating material banned in the 1970s may still be haunting us, according to new research that suggests links between higher levels of exposure during pregnancy and significantly increased odds of autism spectrum disorder in children. According to the research, children born after being exposed to the highest levels of certain compounds of the chemicals, called organochlorine chemicals, during their mother's pregnancy were roughly 80 percent more likely to be diagnosed with autism when compared to individuals with the very lowest levels of these chemicals. That also includes those who were completely unexposed."
Genetic heritability and shared environmental factors among twin pairs with autism.
Arch Gen Psychiatry. 2011 Nov;68(11):1095-102
"Susceptibility to ASD has moderate genetic heritability and a substantial shared twin environmental component."
Gestational Exposure to Endocrine-Disrupting Chemicals and Reciprocal Social, Repetitive, and Stereotypic Behaviors in 4- and 5- Year Old Children: The HOME Study
Environmental Health Perspectives
"Some EDCs were associated with autistic behaviors in this cohort, but our modest sample size precludes us from dismissing chemicals with null associations. Perfluorooctane,β-hexachlorocyclohexane, PCB-178, PBDE-28,PBDE-85,and trans-nonachlor deserve additional scrutiny as factors that may be associated with childhood autistic behaviors."
Genetic heritability and shared environmental factors among twin pairs with autism.
Arch Gen Psychiatry. 2011 Nov;68(11):1095-102
"Susceptibility to ASD has moderate genetic heritability and a substantial shared twin environmental component."
Gestational Exposure to Endocrine-Disrupting Chemicals and Reciprocal Social, Repetitive, and Stereotypic Behaviors in 4- and 5- Year Old Children: The HOME Study
Environmental Health Perspectives
"Some EDCs were associated with autistic behaviors in this cohort, but our modest sample size precludes us from dismissing chemicals with null associations. Perfluorooctane,β-hexachlorocyclohexane, PCB-178, PBDE-28,PBDE-85,and trans-nonachlor deserve additional scrutiny as factors that may be associated with childhood autistic behaviors."
Toxicity biomarkers in autism spectrum disorder: a blinded study of urinary porphyrins
Pediatr Intl. 2011 Apr;52(2):147-53
"Recent studies suggest that children diagnosed with an autism spectrum disorder (ASD) have significantly increased levels of urinary porphyrins associated with mercury (Hg) toxicity, including pentacarboxyporphyrin (5cxP), precoproporphyrin (prcP), and coproporphyrin (cP), compared to typically developing controls... Participants diagnosed with an ASD had significantly increased levels of 5cxP, prcP, and cP in comparison to controls. No significant differences were found in non-Hg associated urinary porphyrins (uroporphyrins, hexacarboxyporphyrin, and heptacarboxyporphyrin). There was a significantly increased odds ratio for an ASD diagnosis relative to controls among study participants with precoproporphyrin (and) coproporphyrin."
Contributions of the environment and environmentally vulnerable physiology to autism spectrum disorders
Curr Opin Neurol. 2010 Apr;23(2):103-10
"This review presents a rationale and evidence for contributions of environmental influences and environmentally vulnerable physiology to autism spectrum disorders (ASDs)... Recent studies suggest a substantial increase in ASD prevalence above earlier Centers for Disease Control figures of one in 150, only partly explicable by data artifacts, underscoring the possibility of environmental contributors to increased prevalence. Some gene variants in ASD confer altered vulnerability to environmental stressors and exposures. De-novo mutations and advanced parental age as a risk factor for ASD also suggest a role for environment. Systemic and central nervous system pathophysiology, including oxidative stress, neuroinflammation, and mitochondrial dysfunction can be consistent with a role for environmental influence (e.g. from air pollution, organophosphates, heavy metals) in ASD, and some of the underlying biochemical disturbances (such as abnormalities in glutathione, a critical antioxidant and detoxifier) can be reversed by targeted nutritional interventions. Dietary factors and food contaminants may contribute risk. Improvement and loss of diagnosis in some with ASD suggest brain circuitry amenable to environmental modulation."
Pediatr Intl. 2011 Apr;52(2):147-53
"Recent studies suggest that children diagnosed with an autism spectrum disorder (ASD) have significantly increased levels of urinary porphyrins associated with mercury (Hg) toxicity, including pentacarboxyporphyrin (5cxP), precoproporphyrin (prcP), and coproporphyrin (cP), compared to typically developing controls... Participants diagnosed with an ASD had significantly increased levels of 5cxP, prcP, and cP in comparison to controls. No significant differences were found in non-Hg associated urinary porphyrins (uroporphyrins, hexacarboxyporphyrin, and heptacarboxyporphyrin). There was a significantly increased odds ratio for an ASD diagnosis relative to controls among study participants with precoproporphyrin (and) coproporphyrin."
Contributions of the environment and environmentally vulnerable physiology to autism spectrum disorders
Curr Opin Neurol. 2010 Apr;23(2):103-10
"This review presents a rationale and evidence for contributions of environmental influences and environmentally vulnerable physiology to autism spectrum disorders (ASDs)... Recent studies suggest a substantial increase in ASD prevalence above earlier Centers for Disease Control figures of one in 150, only partly explicable by data artifacts, underscoring the possibility of environmental contributors to increased prevalence. Some gene variants in ASD confer altered vulnerability to environmental stressors and exposures. De-novo mutations and advanced parental age as a risk factor for ASD also suggest a role for environment. Systemic and central nervous system pathophysiology, including oxidative stress, neuroinflammation, and mitochondrial dysfunction can be consistent with a role for environmental influence (e.g. from air pollution, organophosphates, heavy metals) in ASD, and some of the underlying biochemical disturbances (such as abnormalities in glutathione, a critical antioxidant and detoxifier) can be reversed by targeted nutritional interventions. Dietary factors and food contaminants may contribute risk. Improvement and loss of diagnosis in some with ASD suggest brain circuitry amenable to environmental modulation."
