The findings support other studies on the adverse health effects of this group of environmental contaminants.
A sample of 901 participants in MoBa, who were pregnant in 2003/4, took part in this study. Blood samples from week 17 of pregnancy were analysed for perfluorooctane sulphonate (PFOS) and perfluorooctanoic acid (PFOA), two types of PFAS.
- All pregnant women had measurable levels of PFOS and PFOA in the blood
- Birth weight was about 100 g lower in children of mothers with the highest levels compared with children of mothers with the lowest levels
- There was no difference in the incidence of premature birth or larger growth deviations
- Levels in the Norwegian women were comparable with those found in similar studies in other countries
Facts about perfluorinated alkylated substances (PFAS)
In animal experiments, a clear risk of adverse effects such as retarded foetal growth is seen if the animals are exposed to PFAS in large concentrations. Humans are usually exposed to much lower concentrations. Several of the properties of PFAS are still worrying, and many countries have introduced measures to limit its use. The levels found in humans have therefore dropped in recent years.
The authors of the study draw attention to the fact that physiological factors associated with pregnancy may be an alternative explanation as to why women with the highest PFAS levels had children with lower birth weight.
The study was performed in collaboration with the National Institutes of Environmental Health in the USA.
Perfluorinated compounds in relation to birth weight in the Norwegian Mother and Child Cohort Study. Kristina W. Whitworth, Line S. Haug, Donna D. Baird, Georg Becher, Jane A. Hoppin, Rolv Skjaerven, Cathrine Thomsen, Merete Eggesbo, Gregory Travlos, Ralph Wilson, Lea A. Cupul-Uicab, Anne Lise Brantsaeter, and Matthew P. Longnecker. Am J Epidemiol. 2012, 175: 1209-1216
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