Changing Environment & Human Health
Title: A circumpolar study of new contaminants in women of reproductive age; an assessment in human blood, dietary sources and possible associations to pregnancy outcome
Summary of Activity
In recent Norwegian-Russian study new contaminants, like brominated flame retardants and perfluorinated alkylated substances (PFAS) were detected in blood of pregnant women from northern Norway and Russia. That pilot study confirmed that new contaminants are transported to the Arctic and accumulates in the human body. PBDEs have previously been reported in Norwegian humans but the PFAS have previously not been determined in either Norwegian or Russian human samples. Details are provided in the SPFO-rapport: 930/2005 from the Norwegian State Pollution Control (SFT). Polybrominated diphenyl ethers (PBDEs) were found in all women, and the levels were higher in the Norwegian samples. PFOS was determined in 70 % of the samples, and some levels were even higher than more known pollutants like PCBs. For PFOS there were also clear differences in isomeric distribution in the different samples. PFOS has also been found in high levels in humans from northern Canada.
Classical POPs like PCBs and chlorinated pesticides were also found in most samples, confirming previous findings from AMAP.
Several physical and biological conditions in the Arctic have resulted in very high levels of some classical POPs in marine food chains. Indigenous people have thus become a vulnerable group due to the high levels of POPs in their traditional food. For the emerging contaminants it is important to establish potential sources and routes of exposure in order to ensure that regulations are implemented in the right places and before levels have become too high. To accomplish this it is important to have good data on human distribution of these compounds as well as in different food sources.
Due to the special conditions in the Arctic this region is an important indicator region for assessing compounds were regulations might be needed. Through the established network of AMAP, South Africa and Brazil have been used as reference countries. In these countries we have no information on the levels of these new compounds and they will again be included as reference countries. This also helps in the understanding of the global distribution of these compounds.
The reason for using delivering (pregnant) women in these studies is that the embryonic and fetal period are the most vulnerable periods for possible health effects of contaminants. Most lipid soluble contaminants pass more or less freely across the placenta. Thus for the classical POPs, maternal plasma has been a good indication of the intrauterine levels of POPs. This might not be the case for the PFAS where the compounds have very different physicochemical properties. Analysis of cord blood in addition to maternal blood will give this information. The maternal levels found in the pilot study as well as other studies give reason for concern and the need for follow up studies are evident. The samples are in general taken at the time of delivery in order to have cord blood samples as well.
Through the network of the AMAP human health group and the bilateral agreements with Brazilian and South African partners the applying group will be able to monitor and assess possible reproductive effects. The national networks for sampling and obtaining questionnaire information is well established ensuring homogeneity and comparability of information obtained.
The plan is to adapt an established project protocol in each of the participating countries (QA/QC already performed through the AMAP network); questionnaire information of life style, medical history and dietary habits; medical records of pregnancy outcome; selected analyses of “new” contaminants in blood, like the PBDE-group, the brominated substances, the HBCD-group, the TBBPA, the PFAS-group, the perfluoroalkyl substances, the PCPs, and Pentachloranisol. Others will be considered due to new information. Non-pregnant population groups of different age and sex will be considered due to defined criteria for comparison.
On the basis of this Project selected compounds will be included in the monitoring Programme.
Dr Torkjel M Sandanger
Norwegian Institute for Air Research
Polar Environmental Centre Hjalmar Johansens gt. 14 Tromsø
Prof Jon Øyvind Odland
Institute of Community Medicine (AMAP)
University of Tromsø
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