Easy Targets: How Endocrine-Disrupting Chemicals Affect Reproductive Endocrinology

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Endocrine-disrupting chemicals have been implicated in a wide range of of poor health outcomes, including infertility and obesity. Endocrine News speaks to Almudena Veiga-Lopez, DVM, PhD, the chair of an upcoming ENDO 2025 symposium on these chemicals’ effects on reproductive organs, which are particularly vulnerable to EDCs.

Endocrine-disrupting chemicals are everywhere, and there is seemingly no escape. Polychlorinated biphenyls (PCBs) – previously used in a variety of commercial and industrial applications – have been banned for decades but are still found in soil, sediment, and even certain types of fish, making them “forever chemicals.” Plastic cups had to have stickers on them promising they were bisphenol A (BPA) free. (The two chemicals industry replaced BPA with — bisphenol S [BPS] and bisphenol F [BPF] – have been linked to health risks such as hypertension.) EDCs have been implicated in infertility, diabetes, thyroid dysfunction, obesity, and neurobehavioral problems.

On the evening of July 12, ENDO 2025 in San Francisco will feature an EDCs Special Interest Group (SIG) symposium on how these chemicals affect male and female reproductive endocrinology. The session will hopefully add to the growing awareness of EDCs, making their health impacts as widely recognized as their environmental ubiquity.

“This symposium brings together emerging science on how EDCs affect reproductive endocrinology in both males and females,” says symposium chair Almudena Veiga-Lopez, DVM, PhD, associate professor in the Department of Pathology at the University of Illinois – Chicago. “We are focusing on how physiological context—things like pregnancy, genetic background, or ovarian status—modulates how these chemicals act.”

According to session organizers, the high expression of steroid hormone receptors in reproductive tract tissues, including the gonads, makes them primary targets for EDCs. Veiga-Lopez says that reproductive tissues are incredibly hormone-responsive by design, making them particularly vulnerable to hormone-like compounds.

Speakers will discuss how ovarian function modulates susceptibility to EDCs; maternal metabolic regulation during pregnancy; and how genetic background influences EDC outcomes. “It is a conversation grounded on mechanisms of action, but with clear implications for human health and risk assessment,” Veiga-Lopez says.

Opposite Outcomes

Veiga-Lopez tells Endocrine News that from early development through puberty and into pregnancy or menopause, the reproductive system undergoes complex hormonal transitions, all tightly regulated. EDCs can mimic, block, or otherwise interfere with these hormonal signals — sometimes at very low doses — leading to disruptions in fertility, gametogenesis, hormone production, and more.

“The science of endocrine disruption is no longer just an environmental health issue; it is deeply connected to how we understand hormone biology in the clinic and the lab. This symposium will showcase innovative research; plus, the speakers are fantastic — they will cover mechanisms, real-world implications, and opportunities for future research.” — Almudena Veiga-Lopez, DVM, PhD, associate professor, Department of Pathology, University of Illinois – Chicago, Chicago, Ill.

Investigators are finding that these disruptions are sex-specific, a major theme in recent EDC research. Researchers see differences not just in hormone levels, but also in receptor expression, tissue architecture, detoxification capacity, and epigenetic responsiveness. “For example, the same exposure might impair ovarian follicle development in females while disrupting testosterone production or spermatogenesis in males,” Veiga-Lopez says. “In some cases, males and females exposed to the same EDC can show entirely opposite outcomes. Accounting for these differences is not just good science, but essential for designing meaningful risk assessments and interventions.”

It’s in the Genes

That good science includes looking at a person’s genetic makeup. Veiga-Lopez says that recent studies have revealed EDCs can disrupt the epigenetic programming of germ cells — modifying DNA methylation, histone marks, or non-coding RNAs in ways that can be passed to future generations. Exposure to EDCs during fetal or early postnatal development can interfere with key genes involved in meiosis, folliculogenesis, and spermatogenesis.

“What is particularly fascinating is that some of these changes are not immediately apparent, but rather they remain latent until triggered by physiological stressors,” Veiga-Lopez says. “Some examples of stressors can be metabolic conditions like obesity or insulin resistance, inflammation, exposure to other environmental chemicals (at a later time), or life stage transitions such as menopause. This delayed manifestation complicates how we evaluate risk, but it also opens new windows for understanding disease susceptibility.”

For Veiga-Lopez one of these opened new windows – though not the focus of this particular session — is the recognition that nano- and microplastics can themselves act as endocrine disruptors. These particles can also carry chemicals that can interact with hormone receptors. Their increasing detection in human tissues (including the placenta) raises urgent questions about exposure routes and long-term impacts.

“Within the scope of this session, I am particularly excited by the intersection of reproductive and metabolic disruption,” she says. “We now know that EDCs can influence maternal metabolic adaptation during pregnancy, which can in turn affect reproductive outcomes. The new consensus framework on metabolism-disrupting chemicals is helping bring clarity to these complex relationships. We are also seeing the field move toward greater attention to variability — across sex, genetics, and life stages — which will make toxicology more predictive and human-relevant.”

Moving Forward

Future studies in this area need to capture the complexity of real-life exposures, Veiga-Lopez says. That means moving beyond single chemicals to look at mixtures, low-dose exposures, and cumulative effects across time. “We also need to build models that include sex as a biological variable, consider genetic diversity, and examine how physiological states like pregnancy or metabolic disease affect chemical sensitivity,” she says. “Integrating omics approaches and high-resolution imaging with traditional toxicology will also help us map mechanisms more precisely. And importantly, studies need to consider sensitive windows — especially early development — as key determinants of later health outcomes.”

“We now know that EDCs can influence maternal metabolic adaptation during pregnancy, which can in turn affect reproductive outcomes. The new consensus framework on metabolism-disrupting chemicals is helping bring clarity to these complex relationships. We are also seeing the field move toward greater attention to variability — across sex, genetics, and life stages — which will make toxicology more predictive and human-relevant.” —  Almudena Veiga-Lopez, DVM, PhD, associate professor, Department of Pathology, University of Illinois – Chicago, Chicago, Ill.

The Endocrine Society EDC SIG is helping to shape those future studies. The SIG hosts networking events, scientific sessions, and collaborative initiatives. “It is for anyone interested in how environmental chemicals influence hormone action, whether you are a basic scientist, clinician, public health advocate, or policy expert,” Veiga-Lopez says. “It is a great way to stay on top of emerging science, connect with collaborators, and participate in shaping the Society’s engagement on EDCs, especially as this field becomes increasingly central to public health and clinical endocrinology.”

For now, Veiga-Lopez hopes this session will help move the needle in the direction of better outcomes in fertility, pregnancy, metabolic disease, and hormonal regulation as they relate to EDCs. “The science of endocrine disruption is no longer just an environmental health issue; it is deeply connected to how we understand hormone biology in the clinic and the lab,” she says. “This symposium will showcase innovative research; plus, the speakers are fantastic — they will cover mechanisms, real-world implications, and opportunities for future research.”

Bagley is the senior editor of Endocrine News. In the May issue, he wrote about how early-life EDC exposures could impact brain development later in life.