Neonatal exposure to Thimerosal from vaccines and child development in the first 3 years of life. Neurotoxicol Teratol

Epidemiology and Preventive Medicine, Jagiellonian University Medical College, Krakow, Poland. Electronic address: .
Neurotoxicology and Teratology (Impact Factor: 2.76). 10/2012; 34(6). DOI: 10.1016/
Source: PubMed


Despite the common use of Thimerosal as a preservative in childhood vaccines since the 1930s, there are not many studies on ethylmercury toxicokinetics and toxicodynamics in infants. The knowledge of ethylmercury's potential adverse effects is derived mostly from parallel methylmercury research or from animal and theoretical models.

Aim of the study:
This study was designed to examine the relationship between neonatal exposure to Thimerosal-containing vaccine (TCV) and child development.

Material and methods:
The study sample consisted of 196 infants born between January 2001 and March 2003 to mothers attending ambulatory prenatal clinics in the first and second trimesters of pregnancy in Krakow. Vaccination history (date and the type of the vaccine) was extracted from physicians' records. Child development was assessed using the Bayley Scales of Infant Development (BSID-II) measured in one-year intervals over 3years. General Linear Model (GLM) and Generalized Estimating Equation (GEE) models adjusted for potential confounders were used to assess the association.

An adverse effect of neonatal TCV exposure was observed for the psychomotor development index (PDI) only in the 12th and 24th months of life (β=-6.44, p<0.001 and β=-5.89, p<0.001). No significant effect of neonatal TCV exposure was found in the 36th month. The overall deficit in the PDI attributable to neonatal TCV exposure measured over the course of the three-year follow-up (GEE) was significantly higher in TCV group (β=-4.42, p=0.001). MDI scores did not show the adverse association with neonatal TCV exposure.

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Available from: Renata Majewska, Oct 05, 2015
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    • "Of these studies , 16 were conducted to specifically examine the effects of Thimerosal on human infants and/or children [3–18]. Within these studies, which focused on human infants and/or children, the reported outcomes following Thimerosal exposure were (1) death [3]; (2) acrodynia [4]; (3) poisoning [5]; (4) allergic reaction [6]; (5) malformations [7]; (6) autoimmune reaction [8]; (7) Well's syndrome [9]; (8) developmental delay [10] [11] [12] [13]; and (9) neurodevelopmental disorders, including tics, speech delay, language delay, attention deficit disorder, and autism [10, 11, 14–18]. However, the United States (US) Centers for Disease Control and Prevention (CDC) still insists that there is " no relationship between [T]himerosal[-]containing vaccines and autism rates in children " [19]. "
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    • "Apprehensions about the use of thimerosal-containing influenza vaccines, based on theoretical risk of harm to the fetal brain, were widely spread in scientific and lay communities during the past years [55, 62]. Subsequent research proved that no causal relation existed between immunization with vaccine containing thimerosal preservative—including exposure during pregnancy—and neuropsychological outcomes [63, 64]. The most recent report of the Global Advisory Committee on Vaccine Safety of the World Health Organization considered that available evidence strongly supports the safety of the use of thimerosal as a preservative for inactivated vaccines [65]. "
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