Bisphenol-A (BPA) is associated with adverse health outcomes and is found in many canned foods. It is not understood if some BPA contamination can be washed away by rinsing. The objective of this single-blinded crossover experiment was to determine whether BPA exposure, as measured by urinary concentrations, could be decreased by rinsing canned beans prior to consumption. Three types of hummus were prepared from dried beans, rinsed, and unrinsed canned beans. Fourteen healthy participants ate two samples of each hummus over six experimental days and collected spot urine specimens for BPA measurement. The geometric mean BPA levels for dried beans BPA (GM = 0.97 ng/ml, 95%CI = 0.74,1.26) was significantly lower than rinsed (GM = 1.89 ng/ml, 1.37,2.59) and unrinsed (GM = 2.46 ng/ml, 1.44,4.19). Difference-in-difference estimates showed an increase in GM BPA from pre- to post-hummus between unrinsed and rinsed canned beans of 1.39 ng/ml, p-value = 0.0400. Rinsing canned beans was an effective method to reduce BPA exposure.

Contaminants causing sex-altering, endocrine disrupting-like (ED) effects, or otherwise influencing reproduction, have been of growing concern to humans for more than 50 years. They have also been a perturbing, though less well-studied, phenomenon in marine organisms, following the recognition of tributyltin (TBT)-induced imposex and population extinctions in (neo)gastropods in the 1970s. Whilst ED impacts in mammals and fish are characterized by mimicry or antagonism of endogenous hormones by environmental contaminants (acting through Nuclear Receptors which are present in all metazoans) much less is known regarding pathways to effects in invertebrates. Despite the absence of a defined steroidal/mechanistic component, the extent, severity and widespread nature of ED-like manifestations and altered sexual characteristics observed in marine invertebrates gives rise to comparable concerns, and have been a long-term component of the MBA's research remit. The manifestations seen in sensitive taxa such as molluscs and crustaceans confirm they are valuable indicators of environmental quality, and should be exploited in this capacity whilst we seek to understand the pervasiveness and underlying mechanisms. In so doing, invertebrate indicators address aims of organizations, such as the EEA, OECD, UNEP and WHO, charged with management and monitoring of chemicals and ensuring that adverse effects on humans and the environment are minimized (Bergman et al., 2013). In view of the recent general declines in marine biodiversity, and the potential contribution of ED-like phenomena, safeguarding against deleterious effects through increased research which links pollutant exposure with reproductive dysfunction among invertebrates, is seen as a high priority.

A wide range of health benefits have been ascribed to soya intake including a lowered risk of osteoporosis, heart disease, breast cancer, and menopausal symptoms. Because it is a hormonally active diet, however, soya can also be endocrine disrupting, suggesting that intake has the potential to cause adverse health effects in certain circumstances, particularly when exposure occurs during development. Consequently, the question of whether or not soya phyto-oestrogens are beneficial or harmful to human health is neither straightforward nor universally applicable to all groups. Possible benefits and risks depend on age, health status, and even the presence or absence of specific gut microflora. As global consumption increases, greater awareness and consideration of the endocrine-disrupting properties of soya by nutrition specialists and other health practitioners is needed. Consumption by infants and small children is of particular concern because their hormone-sensitive organs, including the brain and reproductive system, are still undergoing sexual differentiation and maturation. Thus, their susceptibility to the endocrine-disrupting activities of soya phyto-oestrogens may be especially high. As oestrogen receptor partial agonists with molecular and cellular properties similar to anthropogenic endocrine disruptors such as bisphenol A, the soya phyto-oestrogens provide an interesting model for how attitudes about what is ‘synthetic’ v. what is ‘natural,’ shapes understanding and perception of what it means for a compound to be endocrine disrupting and/or potentially harmful. This review describes the endocrine-disrupting properties of soya phyto-oestrogens with a focus on neuroendocrine development and behaviour.

Reproductive parameters of Ligula intestinalis-infected roach (Rutilus rutilus) which were held under long-tem laboratory conditions with unlimited food supply were investigated. Although uninfected and infected roach showed no difference in condition factor and both groups deposited perivisceral fat, the gonadosomatic-index was significantly lower in infected female and male roach. Quantitative histological analysis revealed that gonad development was retarded upon parasitization in both genders. In contrast to the phenotype described in the field, infected females were able to recruit follicles into secondary growth, but a high percentage of secondary growth follicles underwent atresia. In both genders, the histological data corresponded well with reduced expression of pituitary gonadotropins and lowered plasma concentrations of sex steroids, as revealed by real-time RT-PCR and ELISA, respectively. Furthermore, a reduction of vitellogenin mRNA and modulated expression of sex steroid receptors in the liver was demonstrated. Like in the field, there was a significant adverse impact of L. intestinalis on host reproductive physiology which could not be related to parasite burden. Our results show, for the first time, that maintenance under laboratory conditions can not abolish the deleterious effect of L. intestinalis on gametogenesis in roach, and indicate a specific inhibition of host reproduction by endocrine disruption.

Since its use as a model to study metazoan parasite culture and in vitro development, the plerocercoid of the tapeworm, Ligula intestinalis, has served as a useful scientific tool to study a range of biological factors, particularly within its fish intermediate host. From the extensive long-term ecological studies on the interactions between the parasite and cyprinid hosts, to the recent advances made using molecular technology on parasite diversity and speciation, studies on the parasite have, over the last 60 years, led to significant advances in knowledge on host-parasite interactions. The parasite has served as a useful model to study pollution, immunology and parasite ecology and genetics, as well has being the archetypal endocrine disruptor.

The effects of parasite infection by the cestode Ligula intestinalis on the reproductive function and endocrine system of wild roach Rutilus rutilus were evaluated. Gonad maturation, plasma vitellogenin, plasma steroid concentrations (i.e. progesterone, 11-keto-testosterone and 17-β-estradiol) and brain aromatase activity were investigated in relation with parasitization. A low prevalence (8%) of ligulosed roach and a moderate impact of parasitization (mean parasitization index of 8·8%) were found in the studied population. Inhibition of gonad maturation generally resulted from infestation but 5% of the ligulosed roach nevertheless reached maturity. Main sex steroid plasma content was depleted in both genders. Male 11-keto-testosterone, female 17-β-estradiol and progesterone plasma concentrations of both genders were, respectively, 27, 5 and 3 times lower in ligulosed fish when compared to their non-infected counterparts. Progesterone levels were negatively correlated with the parasitization index in females. Brain aromatase activity of infected roach was reduced to 50% of that of the non-infected fish. These results demonstrate significant negative effects on the reproductive function of wild roach infected by the tapeworm L. intestinalis collected from a site with low contamination.

Members of the nuclear steroid hormone superfamily mediate essential physiological functions. Steroid hormone receptors (SHR) act directly on DNA, regulate the synthesis of their target genes and are usually activated by ligand binding. Both endogenous and exogenous compounds and their metabolites may act as activators of SHR and disruptors of endocrine, cellular and lipid homeostasis. The endogenous ligands are generally steroids such as 17β-oestradiol, androgens, progesterone and pregnenolone. The exogenous compounds are usually delivered through the diet and include non-steroidal ligands. Examples of such ligands include isoflavanoids or phyto-oestrogens, and food contaminants such as exogenous oestrogens from hormone-treated cattle, pesticides, polychlorinated biphenyls and plasticisers. Certain drugs are also ligands; so nuclear receptors are also important drug targets for intervention in disease processes. The present review summarises recent reports on ligand-activated SHR that describe the selective regulation of a tightly-controlled cross-talking network involving exchange of ligands, and the control of major classes of cytochrome P450 (CYP) isoforms which metabolise many bioactive exogenous compounds. Many CYP have broad substrate activity and appear to be integrated into a coordinated metabolic pathway, such that whilst some receptors are ligand specific, other sensors may have a broader specificity and low ligand affinity to monitor aggregate levels of inducers. They can then trigger production of metabolising enzymes to defend against possible toxic nutrients and xenobiotic compounds. The influence of dietary intakes of nutrients and non-nutrients on the human oestrogen receptors (α and β), the aryl hydrocarbon receptor, the pregnane X receptor, the constitutive androstane receptor, and the peroxisome proliferator-activated receptors (α and γ), can be examined by utilising computer-generated molecular models of the ligand–receptor interaction, based on information generated from crystallographic data and sequence homology. In relation to experimental and observed data, molecular modelling can provide a scientifically sound perspective on the potential risk and benefits to human health from dietary exposure to hormone-mimicking chemicals, providing a useful tool in drug development and in a situation of considerable public concern.