Choice of biospecimen to be used for optimal biomonitoring requires knowledge of pharmacokinetics -absorption and disposition in the body -to identify the compartment where an absorbed analyte or metabolite exists in greatest concentration. POEAs have a structure similar to aliphatic alkyl polyethoxylates, also known as alcohol polyethoxylates. Therefore, it is likely that POEA metabolites are excreted from the body within a few days, similar to pharmacokinetics of alkyl polyethoxylates. However, knowledge about oxidized metabolites of POEA would improve quantitative biomonitoring. It would also provide insight into the metabolism and urinary excretion fraction (FUE) to back-calculate exposures to POEA, as has been done for nonylphenol ethoxylates. POEAs with shorter EO chains were more frequently found in human plasma than those with longer chains, which was ascribed to (i) the addition of POEAs with a low number of EO units to the GBH and (ii) the possibility that POEAs might go through non-oxidative metabolism to yield shorter EO chains, similar to alkyl polyethoxylates.