Nonylphenol- and octylphenol-ethoxylates in surfactant products : need control or not? : an overview of their consumption, environmental fate and risks and public awareness in Hong Kong as compared to overseas countries

Abstract

Nonylphenol ethoxylates (NPEO) and octylphenol ethoxylates (OPEO), both are alkylphenol ethoxylates (APEO), a type of non-ionic surfactants commonly used in synthetic detergents for household and industrial cleaning purposes. These compounds and their degraded intermediates are xenoestrogens ubiquitously found in runoffs, sewage discharge and sludge. Not only that they persist in our surface waters and sediment, they are also found in the bodies of wildlife and human worldwide. Because of their high volume consumed and their nature as semi-persistent pollutants as well as endocrine disruptors, many developed countries have renounced their use on voluntary basis or through regulatory measure. Hong Kong is situated at the estuary of Pearl River Delta, which is one of the pollution hotspots. It is susceptible to its own water pollutants from municipal sewage (~1,054 million m3/year) and also the discharge (~3.0x109m3/ year) along the river from the industrialized and urbanized Mainland China cities. The local environment and human health are exposed to risks of these chemicals ascribed to rising consumption of detergents and their insufficient removal by sewage treatment, in addition to food intake in particular seafood. However, public awareness about APEO and endocrine disrupting chemicals is low due to no mandatory disclosure and control of these chemicals as well as the uncertainties about their chronic toxicity, based on the survey results of online questionnaires. Several recommendations have been made with reference to overseas regulatory measures and good practices to control and reduce the use of these chemicals.