Environmental Estrogenic Effects of Alkylphenol Ethoxylates

Abstract

Alkylphenol ethoxylates (APEs) and related compounds recently have been reported to be estrogenic because it has been demonstrated in laboratory studies that they mimic the effects of estradiol both in vitro and in vivo. Chemicals referred to as "environmental estrogens" are suspected of causing health effects in both humans and wildlife through disruption of the endocrine system. In this review, the occurrence, environmental fate, and biological effects of APEs are presented. To provide understanding of the potential for endocrine disruption due to environmental estrogens, the physiology of estrogens in mammals and fish is also reviewed. The estrogenic potency of other environmental estrogens is compared to the potency of APE degradation products. The reproductive effects of estrogenic compounds are considered when evaluating the potential health effects of APEs. Given the reported environmental concentrations and bioconcentration factors of APE products, the potential for these compounds to produce estrogenic effects in the environment appears low. Although questions concerning the physiological effects of APEs and other environmental estrogens remain unanswered, there are indications that research is in progress that will lead to better understanding of the risks to humans and wildlife.

Lack of Modifying Effects of Environmental Estrogenic Compounds on the Development of Thyroid Proliferative Lesions in Male Rats Pretreated with N‐Bis(2‐hydroxypropyl)nitrosamine (DHPN)

“…30) Thus, our results suggest that SI and GEN may not be involved in the thyroid goitrogenic effects of soybean. NP has been shown to possess estrogen-like properties, 31) being positive in a uterotropic bioassay in mice 32) and rats 29) and stimulating the growth of estrogen-dependent MCF-7 cells. 32) NP was also found to increase the proliferative activity of epithelial cells of the Noble rat mammary gland 33) and to stimulate vitellogenin production, 34) a process that is normally estrogen-dependent.…”

Distinct expression and activity profiles of largemouth bass (Micropterus salmoides) estrogen receptors in response to estradiol and nonylphenol

“…NP is a microbial breakdown product of NP polyethoxylates (NPEs) that are most commonly found in industrial non-ionic surfactants and also used in the production of plastics, textiles, paints, emulsifiers, paper products, and cosmetics (Scott & Jones 2000, Sabik et al 2003. It is estimated that more than 500 000 tons of NPEs are used annually (Scott & Jones 2000) with O60% entering the environment via sewage outflows (White et al 1994, Nimrod & Benson 1996, Canadian 2000.…”

Enhancing effect of the endocrine disruptor para-nonylphenol on the generation of reactive oxygen species in human blood neutrophils.

“…Alkylphenols are widely used as components in chemically synthesized products such as plastics, detergents, and other formulated products (Nimrod and Benson 1996). They are degraded to free para-nonylphenol (NP) in seawater or sewage sludge (Ekeland et al 1993;Giger et al 1984), and it accumulates in plants and animals in the aquatic environment (Ahel et al 1993).…”