Halogenated alkylphenol ethoxylates

The quantitative environmental analysis of surfactants, such as alcohol ethoxylates, alkylphenol ethoxylates (APEOs) and linear alkylbenzene sulfonates (LASs), is complicated by the presence of a multitude of isomers and oligomers in the source mixtures (see Chapter 2). This issue bears many similarities to the quantitation problems that have occurred with halogenated aromatic compound mixtures, e.g. polychlorinated biphenyls (PCBs) [1]. 

Alkylphenol ethoxylate surfactants are widely used in laundry detergents. Chlorination of these compounds results in the formation of halogenated nonylphenolic DBFs, most of them brominated acidic compounds [126],... 

Important classes of nonionic surfactants are aliphatic poly-ethoxylate alcohols (AEO), and octyl or nonyl phenol polyethoxylates (OPEO and NPEO). The alkylphenol ethoxylates (APEO) attracted special attention due to their supposedly endocrine disrupting properties (Ch. 8.3). LC-MS analysis may also involve nonylphenolethoxycarboxylates (NPEC), biodegradation products of NPEO, and halogenated analogues, generated in chlorine disinfection treatments in drinking water production plants. 

Nonylphenol ethoxylate (NPEO), octylphenol ethoxylate (OPEO), alkylphenoxy carboxylate (APEC), halogenated alkylphenols (BrOP, ClOP, BrNP, CINP), halogenated NPEOs (BrNPEOs, ClNPEOs) Bisphenol-A (BPA), bisphenol-F (BPF)... 

Among different nonionic surfactant classes, alkyl-phenol ethoxylates (APEOs) comprise the class meriting special attention with respect to environmental issues. The analysis of underivatized alkylphenolic compounds by GC-MS is restricted to the most volatile degradation products, such as alkylphenols and APEOs with less then 4-ethoxy groups. To overcome the problem of volatility, different offline and online derivatization protocols have been developed. Two complementary MS techniques, one using El and another using the less commonly used positive (P)CI, have been evaluated for the analysis of APEOs, their acidic (APECs) and neutral metabolites (APs), and halogenated derivatives. 

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