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LETTER TO THE EDITOR |
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| Year : 2014 | Volume
: 9
| Issue : 3 | Page : 297-298 |
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To what extent do environmental factors contribute to the occurrence of autism spectrum disorders?
Annio Posar1, Paola Visconti2
1 Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
2 Child Neurology and Psychiatry Unit, IRCCS Institute of Neurological Sciences of Bologna, Bologna, Italy
| Date of Web Publication | 23-Dec-2014 |
Correspondence Address:
Annio Posar
Child Neurology and Psychiatry Unit, IRCCS Institute of Neurological Sciences of Bologna, Department of Biomedical and Neuromotor Sciences, University of Bologna, Via Altura 3, 40139 Bologna
Italy
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/1817-1745.147610
How to cite this article:
Posar A, Visconti P. To what extent do environmental factors contribute to the occurrence of autism spectrum disorders?. J Pediatr Neurosci 2014;9:297-8 |
Dear Sir,
Autism spectrum disorders (ASD) are lifelong, devastating neurodevelopmental disorders, presenting in early childhood that severely impair social abilities and personal autonomy of the affected individuals. According to Diagnostic and Statistical Manual of Mental Disorders, 5 th edition criteria, ASD are characterized by persisting deficits in social communication and interaction, and by restricted, repetitive behaviors, interests, and activities. [1]
Recently, autism prevalence has increased dramatically up to 1-2% of children. [2] A real, significant increase in ASD prevalence during these last decades is indisputable and it urgently requires explanations.
The etiology of autism is multifactorial, with a strong genetic component, but genetics alone is not able to explain this increase in prevalence and the involvement of environmental factors has to be carefully considered. The potential effects of vaccinations have been seriously disputed. [3] A large number of other heterogeneous environmental factors has been taken into account, namely the exposure to air pollutants, particularly heavy metals, and particulate matter, during the prenatal period, but without reaching definitive conclusions. [4] Recently, several studies have identified oxidative stress in patients with autism, [5] but the "primum movens" of this phenomenon remains unknown. Unfortunately, despite all the efforts that have been made in medical research, many aspects of the etiopathogenesis of autism still remain obscure and its prevalence seems to increase dramatically without a plausible explanation. Nowadays, it is necessary to formulate alternative hypotheses for understanding what is behind this phenomenon.
One way to proceed is to pay attention to what has significantly changed in our environment in the last few decades. In this perspective, one possible hypothesis may be the marked increase in electromagnetic pollution, caused by the enormous deployment of modern wireless technologies (e.g., mobile phones). Many literature data support the biological and health effects of electromagnetic pollution, including carcinogenicity, [6] probably mediated by DNA damages. Moreover, the genetic instability induced by electromagnetic fields (EMF) can also lead to other pathologies. Of course, the fact that the diffusion of wireless technologies coincides chronologically with the increase in the autism prevalence does not necessarily imply a correlation, but the hypothesis that electromagnetic pollution constitutes at least a predisposing pre-, peri-, and postnatal factor to autism deserves to be examined carefully.
Recent data seem to support this hypothesis, suggesting that autistic symptoms may be the consequence of electrophysiological oscillatory synchronization alterations, and that EMF and radiofrequency radiation (RFR) could lead to such alterations. The hypothesized EMF/RFR pathogenic mechanisms underlying autism include DNA damage, oxidative stress, increase of intracellular calcium, immune system dysfunction, blood-brain barrier disruption. [7],[8] A recent study suggested a correlation between occupational electromagnetic exposure of parents and ASD in their children, even if these data need confirmation due to the young age of the children evaluated. [9]
An epidemiological study is warranted in order to explore the possible link between the prevalence of autism and the extent of electromagnetic pollution. This would require the involvement of multiple centers, distributed in various geographical areas with different levels of EMF/RFR exposure. The use of homogeneous and standardized criteria (including phenotypic observation and neurobehavioral assessment) is crucial to obtain significant and reliable results.
We hope that this proposal may stimulate collaboration among professionals dealing with autism in order to further investigate the possible environmental factors contributing to the increasing prevalence of ASD.
 Acknowledgments | |  |
The authors would like to thank Cecilia Baroncini for linguistic support.
| References | | |
| 1. | American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5 th ed. Washington, DC: American Psychiatric Association; 2013.  |
| 2. | Developmental Disabilities Monitoring Network Surveillance Year 2010 Principal Investigators, Centers for Disease Control and Prevention (CDC). Prevalence of autism spectrum disorder among children aged 8 years - Autism and developmental disabilities monitoring network, 11 sites, United States, 2010. MMWR Surveill Summ 2014;63:1-21. |
| 3. | Taylor LE, Swerdfeger AL, Eslick GD. Vaccines are not associated with autism: An evidence-based meta-analysis of case-control and cohort studies. Vaccine 2014;32:3623-9. |
| 4. | Lyall K, Schmidt RJ, Hertz-Picciotto I. Maternal lifestyle and environmental risk factors for autism spectrum disorders. Int J Epidemiol 2014;43:443-64. |
| 5. | Ghezzo A, Visconti P, Abruzzo PM, Bolotta A, Ferreri C, Gobbi G, et al. Oxidative stress and erythrocyte membrane alterations in children with autism: Correlation with clinical features. PLoS One 2013;8:e66418. |
| 6. | Baan R, Grosse Y, Lauby-Secretan B, El Ghissassi F, Bouvard V, Benbrahim-Tallaa L, et al. Carcinogenicity of radiofrequency electromagnetic fields. Lancet Oncol 2011;12:624-6. |
| 7. | Herbert MR, Sage C. Autism and EMF? Plausibility of a pathophysiological link - Part I. Pathophysiology 2013;20:191-209. |
| 8. | Herbert MR, Sage C. Autism and EMF? Plausibility of a pathophysiological link part II. Pathophysiology 2013;20:211-34. |
| 9. | Pino-López M, Romero-Ayuso DM. Parental occupational exposures and autism spectrum disorder in children. Rev Esp Salud Publica 2013;87:73-85. |
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