Unveiling the Occurrence, Ecotoxicity, Risks, and Removal of Major Nonylphenol Ethoxylate Alternatives in the Aquatic Environment

With increasingly stringent global
regulations on nonylphenol
ethoxylates
(NPEO), the use of NPEO alternatives has increased significantly,
resulting in their widespread environmental occurrence and notable
ecological risks. This review synthesizes the global occurrence of
NPEO alternatives in surface waters, their toxicological impacts on
aquatic organisms, their associated ecological risks, and an evaluation
of treatment techniques. Based on the existing global detection data,
Europe had the highest detection frequency, and linear alkylbenzenesulfonate
(LAS) was the predominant alternative. Toxicological studies demonstrated
that these alternatives induce multiple adverse effects in aquatic
species, including mortality, behavioral abnormalities, and tissue/organ
dysfunction, with fish and crustaceans showing particular sensitivity.
Ecological risk assessments revealed that NPEO alternatives posed
acute and chronic risks (hazard quotient >1) in 84% and 80% of
investigated
sites globally, respectively, with LAS being the primary risk driver,
whereas alkyl ether sulfate (AES) presented negligible risks. Among
treatment technologies, biodegradation was the most widely used but
exhibited varying removal efficiencies (30–100%), whereas membrane
filtration achieved the highest average removal rate (91.53%). Given
their widespread occurrence, ecological threats, and inadequate removal,
strengthened risk control and the development of greener alternatives
are urgently needed.