Estimation of the total concentration of perfluoroalkyl acids (PFAA) in human serum: Data from NHANES 2005-2012

While selected perfluoroalkyl acids/substances (PFAAs) like perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) have been detected and measured in laboratory, a method to estimate the total concentration of PFAAs (∑PFAA) in serum has not been developed. Because of the health concerns associated with PFAAs and because of the inability of every laboratory to measure every PFAA as well as because of the non-availability of sensitive enough equipment to be able to detect very small amounts of certain PFAAs, it is of interest to know ∑PFAA. We used data from the National Health and Nutrition Examination Survey for the years 2005-2012 to develop regression models to estimate ∑PFAA by using the levels of PFOA and PFOS only. While data for 2005-2008 were used to develop regression models, data for 2009-2012 were used to evaluate the accuracy of the developed models. Over 63% of observed values for evaluation data were found to be within 10% of the predicted values. The model so developed can be used with just the knowledge of the age, gender, and concentrations of PFOA and PFOS. While the data used to develop the model were generated in U.S., the model can be used to estimate ∑PFAA for data collected in North America and Europe and probably elsewhere in the world.