HTC-15 - Abstract

Abstract Information :

In studies on the health effects of environmental chemicals it is desirable that multiple compound groups can be analyzed from the same low volume serum aliquot. Thus, we have developed analytical method for simultaneous determination of three different compound groups, which are associated with a variety of adverse health outcomes. Perfluoroalkyl substances (PFAS), found in both environmental and human samples, are widely used in many industrial and commercial applications and as a result in consumer products. PFAS have been associated with various adverse health effects, such as elevated total and LDL cholesterol, increased breast cancer risk and disruption of thyroid hormones1-5. Parabens are preservatives commonly used in personal care products, pharmaceuticals, and foods. These compounds can possibly act as endocrine disruptors, and have been associated with impairments on the reproductive systems and increased breast cancer incidence6. Also they are suspected to interfere with male reproductive functions and to influence development of malignant melanoma. Exposure to tobacco smoke through smoking and second hand smoking has been associated with a variety of adverse health outcomes, including asthma, emphysema, fetal growth and cancer. In addition, smokeless nicotine exposure has been associated with several oral disorders7. This exposure can be evaluated by analyzing a cotinine, the primary metabolite of nicotine, in serum.

A simple and high throughput method for analysis of 21 PFAS, 8 parabens and cotinine from 0.1 mL of serum was developed. The serum sample was pre-treated with two step extractions, and all the analytes were separated and detected with LC-MS/MS. The limit of quantitation (LOQs) for PFAS, parabens and cotinine were 0.1 - 0.3 ng/mL, 0.20 - 1.0 ng/mL and 0.10 ng/mL, respectively. These limits are highly sufficient for studies where the exposure effects of PFASs, parabens and tobacco smoke is evaluated.

The main PFAS found in serum were perfluorooctanesulfonate (PFOS, range 1.3 - 23 ng/mL), perfluorooctanoate (PFOA, range 0.54 - 6.6 ng/mL), perfluorononanoate (PFNA, range 0.19 - 4.1 ng/mL) and perfluorohexanesulfonate (PFHxS <0.15 - 5.5 ng/mL). For parabens the methyl (range <1.0 - 49 ng/mL) and propyl (range <0.2 - 1100 ng/mL) conjugates were the abundant compounds found in this study. Cotinine level in serum of tobacco smokers was over 50 ng/mL, whereas in serum of non-smokers the level was usually below 0.1 ng/mL. Analysis throughput time for 150 serum samples is one week. Besides the high throughput performance, the developed method is suitable for studies where the sample volume is limited since only a low sample volume from 0.05 to 0.1 mL serum is needed.