A special issue in the volume 101 of the peer-reviewed journal Hormones and Behavior, published in May 2018, focuses on endocrine disrupting chemicals (EDCs) and behavior.
The accompanying editorial is written by Emily Barrett from the Rutgers University and Heather Patisaul from the North Carolina State University, both U.S.. Barrett and Patisaul emphasize that the special issue on EDCs and behavior “comes at a critical point when U.S. chemical regulatory policy is being reevaluated and important protections, like the Endocrine Disruptor Screening Program and the National Center for Environmental Research, risk loss of funding.” Importantly, the 14 peer-reviewed articles included in the special issue “make an eloquent case for why we must continue to study endocrine disruptors.” The featured research adopts various approaches “from studying the biochemical and molecular mechanisms underlying endocrine disruption, to synthesizing large bodies of epidemiological work.” Collectively, this work raises “concern about how many of the 90,000+ chemicals in use today may disrupt our most basic endocrine systems with significant consequences for neurodevelopment, neurophysiology, healthy brain aging, and behavior.”
The review by Gore and colleagues discusses “how EDCs affect the development and manifestation of sexual traits, reproductive competence, and sexual behavior.”
Moosa and colleagues summarize the evidence on the “controversial question of whether widespread exposure to EDCs is contributing to the much publicized rise in autism spectrum disorders.” They focus on EDCs’ roles in the etiology of neurodevelopmental diseases and conclude that “prenatal exposures to EDCs . . . may cause long-lasting, epigenetic changes that contribute to disease risk in future generations.”
The review by Walley and Roepke addresses behavioral aspects involved in obesogenic actions of EDCs. They critically assess the scarce literature looking at the EDCs’ impact on feeding behavior and the associated neural circuits and “make recommendations regarding how research should progress in this underserved area of EDC research.”
Meakin and colleagues examine “EDC impacts on stress hormones” and show that “environmental adversity impacts the methylation of genes critical for HPA [(hypothalamic-pituitary-adrenal)], but also placental, function, with potential long-lasting effects on children’s neurodevelopment.” Another review by Sobolewski and colleagues also focuses on the stress axis and examines “interactions between maternal stress and chemical exposures.” The point out that some neurotoxic metals can act as EDCs, “by altering HPA axis and central nervous system activity, thereby disrupting behavior.”
Several articles address bisphenol A (BPA, CAS 80-05-7). Nesan and colleagues focus on “how BPA impacts the developing brain.” MacKay and Abizaid “highlight BPA’s ability to interact with a wide variety of hormone receptors . . . and discuss what this means for interpreting a complex and often seemingly paradoxical literature.” Further, Harris and colleagues “examine the potential for behavioral and other effects [of BPA] to be inherited by subsequent generations.” For example, they show that “gestational exposure to BPA affects pup ultrasound vocalizations, a measure of social communication, and adult operant responding in mice.” In another study, published on June 18, 2018 in the peer-reviewed journal PLoS One, similar findings were also reported for California mice. This species is used as a special model for parental behaviors with high relevance to humans, because they are monogamous, with both parents caring for neonates. In this study, Johnson and colleagues found changes in the vocalization patterns of the mice pups whose parents were exposed to BPA prenatally (i.e., through exposure of grandparents). These changes in communication abilities could have impacts on the amount of parental care they receive.
Braun and colleagues demonstrate that exposure to triclosan (CAS 3380-34-5) can alter thyroid activity in early childhood. The implications of their research are “extensive given the essential role of thyroid hormones in maturation of the brain, and particularly the cerebral cortex, during early development.” Further, a study by Heerema and colleagues “identifies a novel role for thyroid hormones on olfaction-related behaviors in tadpoles” and shows that “exposure to a cocktail of . . . chemicals found in municipal wastewater can . . . [result] in compromised predator avoidance behavior.” Important, this study “is a prescient reminder that all species, not just humans, are exposed to EDCs and at risk for adverse neurodevelopmental outcomes that compromise fitness and, possibly, survival.”
Vuong and colleagues review epidemiological literature on behavioral effects of polybrominated diphenylethers (PBDEs), also known to disrupt thyroid system. They conclude that “prenatal (and in some cases, early postnatal) exposure is linked to hyperactivity, conduct problems, and impaired executive functions in childhood,” building “a clear case in which links between exposures, even at low doses, and neurodevelopmental effects in children is particularly strong.”
Høyer and colleagues address perfluoroalkyl substances (PFASs), and in particular the newer type of short-chain PFASs used to replace the long-chain PFASs that are being phased out. They discuss studies “finding that prenatal exposure to several of these replacement chemicals may be linked to hyperactivity and other problem behaviors in children.” This review highlights the “pervasive problem of ‘regrettable substitution’ when one problematic chemical, or class of chemicals, is replaced by another that also poses health concerns.” It further “signals a clear need to better understand how these chemicals impact hormone-sensitive systems and behavioral endpoints.”
Science Daily (June 18, 2018). “BPA can induce multigenerational effects on ability to communicate.”
“Endocrine Disrupting Chemicals and Behavior.” Hormones and Behavior 101(Suppl C): 1-148.
Emily Barrett and Heather Patisaul (2018). “Introduction to the special issue on endocrine disrupting chemicals and behavior.” Hormones and Behavior 101:1-2.
Gore, A., et al. (2018). “Mate choice, sexual selection, and endocrine-disrupting chemicals.” Hormones and Behavior 101: 3-12.
Moosa, A., et al. (2018). “Are endocrine disrupting compounds environmental risk factors for autism spectrum disorder?” Hormones and Behavior 101: 13-21.
Sabrina Walley and Troy Roepke (2018). “Perinatal exposure to endocrine disrupting compounds and the control of feeding behavior—An overview.” Hormones and Behavior 101: 22-28.
Meakin, C., et al. (2018). “Placental CpG methylation of HPA-axis genes is associated with cognitive impairment at age 10 among children born extremely preterm.” Hormones and Behavior 101: 29-35.
Sobolewski, M., et al. (2018). “Endocrine active metals, prenatal stress and enhanced neurobehavioral disruption.” Hormones and Behavior 101: 36-49.
Nesan, D., et al. (2018). “Opening the black box of endocrine disruption of brain development: Lessons from the characterization of Bisphenol A.” Hormones and Behavior 101: 50-58.
Harry MacKay and Alfonso Abizaid (2018). “A plurality of molecular targets: The receptor ecosystem for bisphenol-A (BPA).” Hormones and Behavior 101: 59-67.
Harris, P., et al. (2018). “Effects of maternal or paternal bisphenol A exposure on offspring behavior.” Hormones and Behavior 101: 68-76.
Braun, J., et al. (2018). “Associations of early life urinary triclosan concentrations with maternal, neonatal, and child thyroid hormone levels.” Hormones and Behavior 101: 77-84.
Heerema, J., et al. (2018). “Behavioral and molecular analyses of olfaction-mediated avoidance responses of Rana (Lithobates) catesbeiana tadpoles: Sensitivity to thyroid hormones, estrogen, and treated municipal wastewater effluent.” Hormones and Behavior 101: 85-93.
Vuong, A., et al. (2018). “Exposure to polybrominated diphenyl ether (PBDEs) and child behavior: Current findings and future directions.” Hormones and Behavior 101: 94-104.
Høyer, B., et al. (2018). “Exposure to perfluoroalkyl substances during pregnancy and child behavior at 5 to 9 years of age.” Hormones and Behavior 101: 105-112.
Mary Catanese and Laura Vandenberg (2018). “Developmental estrogen exposures and disruptions to maternal behavior and brain: Effects of ethinyl estradiol, a common positive control.” Hormones and Behavior 101: 113-124.
Bauer, A., et al. (2018). “Prenatal paracetamol exposure and child neurodevelopment: A review.” Hormones and Behavior 101: 125-147.
Johnson, S., et al. (2018). “Multigenerational effects of bisphenol A or ethinyl estradiol exposure on F2 California mice (Peromyscus californicus) pup vocalizations.” PLoS ONE 13(6):e0199107.