Specific in vitro toxicity of crude and refined petroleum products: 3. Estrogenic responses in mammalian assays

Abstract

Current petroleum risk assessment considers only narcosis as the mode of action, but several studies have demonstrated that oils contain compounds with dioxin-like, estrogenic or antiestrogenic, and androgenic or antiandrogenic activities. The present study is the third in a series investigating the specific toxic effects of 11 crude oils and refined products. By employing recombinant mammalian cells stably transfected with the human estrogen receptor alpha (ERα) or beta (ERβ), and expressing the luciferase protein (ERα-U2OS-Luc and ERβ-U2OS-Luc assay), the estrogenicity or antiestrogenicity of oils was studied. All oils, except for two refined oils and one crude oil, induced estrogenic responses. The calculated estrogenic potencies of the oils were six to nine orders of magnitude lower than the potency of 17β-estradiol (E2). Upon coexposure to a fixed concentration of E2 and increasing concentrations of oils, additive, antagonistic, and synergistic effects were revealed. One nautical fuel oil was tested in the human breast carcinoma cell line MCF-7, in which it induced cell proliferation up to 70% relative to the maximal induction by E2. At its minimum effect concentration of 25 mg/L, the oil was also capable of inducing mRNA expression of the estrogen-dependent protein pS2 by a factor of two. The present results indicate that oils naturally contain potentially endocrine-disrupting compounds that are able to influence the estrogenicity of other compounds and may cause biological responses beyond receptor binding.

The Gulf Long-Term Follow-Up Study (GuLF STUDY): Biospecimen collection at enrollment

“…The samples may also be useful in examining possible endocrine effects, such as altered plasma levels of cortisol and prolactin, which were previously noted among oil spill clean-up workers (Perez-Cadahia et al 2008a; Perez-Cadahia et al 2007); such analyses will need to consider time of collection to account for circadian rhythms. Such effects were also observed in relation to certain metals commonly found in crude oil (Vrabie et al 2011; Lafuente 2013), although metal concentrations in the DWH oil were relatively low (Liu et al 2012). In addition, the blood specimens may be examined for certain immune effects such as altered cytokine levels.…”

An evaluation of the endocrine disruptive potential of crude oil water accommodated fractions and crude oil contaminated surface water to freshwater organisms using in vitro and in vivo approaches

“…Crude oil has been shown to exhibit estrogenicity, but the potency seems to vary considerably among different kinds of crude oil (from different locations) and to occur predominantly via ESR2 and not ESR1 . The fact that the yeast screen applied in the present study only represented ESR1 therefore possibly explains the absence of estrogenicity observed for the crude oils tested.…”

Pathogenicity of Endocrine Dysregulation in Autism: The Role of the Melanin-Concentrating Hormone System

“…Crude and refined petroleum products affect ERα and ERβ and may disrupt sexual development and dimorphism with relatively low concentrations needed to trigger ER activation in human tissues [266,267]. With many industrial compounds derived from petroleum, the estrogenic impact is pervasive.…”