Ortega García et al. Journal of Medical Case Reports 2011, 5:129 http://www.jmedicalcasereports.com/content/5/1/129 Page 4 of 5 Table 2 Environmental risk factors studied in autism/autism spectrum disorder (ASD) in the scientific literature Risk factors Comments Thalidomide Time of critical exposure: 20 to 24 days after conception Misoprostol Time of critical exposure: first trimester, near sixth week after conception. Used for illegal abortion. Valproic acid Time of critical exposure: first 3 to 4 weeks after conception. Neural tube defects, cardiac malformations, craniofacial malformation. Rubella infection Time of critical exposure: infection during the first 8 weeks Chlorpyrifos Pesticide used at home, school, community and farms Organochlorated pesticides Dicofol and endosulfan exposure. First to eighth weeks. Correlation between maternal residence near agricultural pesticide exposure and autism. Prenatal, neonatal and perinatal Advanced maternal and/or paternal age (mother > 35; father > 40); bleeding during pregnancy; forceps or factors vacuum delivery; prolonged labor; low birth weight (< 2500 g); respiratory distress syndrome; meconium aspiration syndrome; preterm birth at < 33 weeks; breech presentation; gestational age < 35 weeks; mothers who used medicine during pregnancy Maternal immigration/mother Increased risk of ASD according to region and ethnicity; more risk in Caribbean and African-American populations born abroad Daily smoking in early pregnancy The risk of autism is associated with daily smoking in early pregnancy b2-Adrenergic receptor agonist Used to treat premature labor. Continuous terbutaline exposure for 2 weeks had increased risk for ASD. Birth defects Associated with a near twofold increased risk for autism overall Chlorinated solvents and heavy Association between autism and estimated concentrations in ambient air around birth residence. Increased risk metals for solvent and metals (mercury, cadmium, nickel, trichloroethylene and vinyl chloride). Parental psychiatric history Parental psychopathology is associated with risk of autism and effective disorders Alcohol and drugs It is very unlikely that there is a strong association between prenatal alcohol exposure and autism High parental education Families with higher education background will seek services, thus reporting a child with autism Lack of omega 3 fatty acids Studies showed link between childhood development disorders and omega-6, omega-3 imbalances Congenital cytomegalovirus Timing of injury to the developing brain by CMV may be in the third trimester in some patients with ASD (CMV) infection Singleton and concordant Results indicated that ASD-concordant multiple births in boys tended to be higher than expected in March, May multiple births and September, but were 87% less in December, as compared with January Maternal autoimmune disorders Maternal autoimmune disorders in women around the time of pregnancy are unlikely to contribute significantly to risk of autism (case-control study) Fetal alcohol syndrome (FAS) Autistic behavior has not been previously associated with FAS. No statistical data, however it raises awareness (case report) that FAS could be a risk factor that should be evaluated by physicians. Neonatal hyperbilirubinemia Not a risk factor associated with ASD. Children with any degree of bilirubin level elevation were not at increased risk of ASD. Antenatal ultrasound Antenatal ultrasound is unlikely to increase the risk of ASD (case-control study) Ammonium perchlorate No reports of risk found Mercury (vaccines) No risk found Measles, mumps, rubella (MMR) No evidence that supports MMR vaccination relationship with autism vaccination Pediatric Environmental Health Specialty Units. How- ever, the individual risk assessment for these patients is a complex process that requires specific diagnostic abil- ities. Pharmacological use during pregnancy is a known risk factor for autism and the relationship described seems plausible, however it is necessary to be cautious with the interpretation of these issues [21]. Although the use of herbal supplements during pregnancy is rela- tively common, there is little information on their effects on fetal development. This work also serves to highlight potential secondary physiological effects of over-the-counter herbal remedies, which may include micronutrient imbalance. This case report has several limitations such as the inconsistent composition of her- bal supplements, possible interaction between multiple exposures and the lack of biomarkers in the study. How- ever, the case serves to illustrate a possible mechanism of developmental neurotoxicity through a vitamin defi- ciency potentiated by herbal supplementation and alco- hol exposure. Conclusions As further scientific evidence accumulates, a detailed and careful PEH should be obtained from all patients with ASD. After analyzing this particular case, it is recommended that maternal exposure to ethanol and