Suspect Screening Analysis of Pooled Human Serum Samples Using GC × GC/TOF-MS

Abstract

Humans interact with thousands of chemicals. This study aims to identify substances of emerging concern and in need of human health risk evaluations. Sixteen pooled human serum samples were constructed from 25 individual samples each from the National Institute of Environmental Health Sciences' Clinical Research Unit. Samples were analyzed using gas chromatography (GC) × GC/time-of-flight (TOF)mass spectrometry (MS) in a suspect screening analysis, with follow-up confirmation analysis of 19 substances. A standard reference material blood sample was also analyzed through the confirmation process for comparison. The pools were stratified by sex (female and male) and by age (≤45 and >45). Publicly available information on potential exposure sources was aggregated to annotate presence in serum as either endogenous, food/nutrient, drug, commerce, or contaminant. Of the 544 unique substances tentatively identified by spectral matching, 472 were identified in females, while only 271 were identified in males. Surprisingly, 273 of the identified substances were found only in females. It is known that behavior and nearfield environments can drive exposures, and this work demonstrates the existence of exposure sources uniquely relevant to females.

Identification and Prioritization of Organic Pollutants in Human Milk from the Yangtze River Delta, China

“…To address these issues, we performed nontargeted analysis to identify organic compounds in 15 pooled human milk samples prepared from 467 individual samples collected from women living in the Yangtze River Delta (YRD), China. Using pooled samples allows a small number of samples to be analyzed to allow exposure of the population of a region to be assessed . The YRD is one of the most economically dynamic areas in China and has a permanent resident population of 235 × 10 6 , which is 16.7% of the population of mainland China.…”