A new Rutgers study found estrogen-mimicking mold toxins in 100% of pregnant participants tested. Here is what the science actually shows, what it does not yet show, and what I tell the women in my practice who are planning a pregnancy.

By Jill Carnahan, MD, ABIHM, ABoIM, IFMCP  |  Medical Director, Flatiron Functional Medicine  |  Louisville, Colorado

I have spent much of my career sitting across from patients whose illness had no name until we looked at their environment. Mold. Mycotoxins. Water-damaged buildings. Contaminated food. Over and over, the answer was not in a rare disease textbook but in the air they were breathing and the food they were eating.

So when I read the results of the Jersey Babies pilot study out of Rutgers, published in late June 2026 in the Journal of Exposure Science & Environmental Epidemiology, my first reaction was not surprise. It was recognition, followed by a quiet ache for every young mother who has ever asked me, “But what could I have done differently?”

Here is the finding, stated plainly: researchers measured zearalenone and its metabolites in the urine of 33 pregnant women in New Brunswick, New Jersey, at three points across pregnancy. At least one of these hormone-mimicking mold toxins was detected in every single sample collected. Not most. Not a concerning majority. All 78 samples.¹

The question is no longer whether pregnant women in the United States are exposed to mycoestrogens. The question is what that exposure is doing, and what we can reasonably do about it.

What Exactly Is a Mycoestrogen?

Zearalenone, usually abbreviated ZEN, is a mycotoxin produced by Fusarium fungi. Fusarium is not an exotic organism. It is one of the most common field pathogens of corn, wheat, oats, rye, barley, and other staple grains worldwide.^2,3

What makes ZEN different from most mycotoxins is its shape. Zearalenone and its metabolites (alpha-zearalenol, beta-zearalenol, and the synthetic analog zeranol) bind directly to both alpha and beta nuclear estrogen receptors and act as agonists of 17-beta-estradiol signaling.⁴ In other words, the body reads them as estrogen. That is why toxicologists gave them their own category name: mycoestrogens.

Three properties make them particularly difficult to avoid:

• They are heat stable. Baking, boiling, extrusion, and industrial processing do not reliably destroy them. A tortilla chip made from contaminated corn still carries the toxin.³
• They travel up the food chain. Livestock eat contaminated feed, and residues appear in meat and dairy. In the United States, zeranol (a synthetic version of alpha-zearalanol) is also permitted as a cattle growth promoter. The European Union banned that use in 1996 over endocrine-disruption concerns.¹
• They clear quickly but are replenished constantly. The half-life is roughly one day.⁵ That should mean levels swing wildly. Instead, the Rutgers team found intraclass correlation coefficients of 0.62 to 0.95 across pregnancy, meaning exposure was remarkably stable from month to month. Stable clearance plus stable measurement equals continuous re-exposure. The tap is always running.

Where It Came From in This Study

Because the Rutgers investigators matched 24-hour dietary recalls to urine samples collected at the same visit, they could do something most exposure studies cannot: trace the toxin back to the plate.

Corn-based foods showed the strongest correlations with urinary mycoestrogens. Corn, corn chips, corn tortillas, masa, cornmeal, corn oil, elote, and pan de elote were associated with ZEN and its metabolites at correlation coefficients ranging up to 0.92. Popcorn, other cereal grains, and cooking oils showed weaker but still statistically significant associations. Chicken and pork, notably, showed weak inverse correlations, suggesting that in this cohort grain was the dominant route rather than meat.¹

Participants who identified as Hispanic had total mycoestrogen concentrations 52 to 109 percent higher than non-Hispanic participants, and also reported significantly higher intake of corn and corn products. The authors were careful, and correct, to interpret this as a dietary and structural finding rather than a biological one. Corn is the crop most vulnerable to Fusarium, and higher corn intake produces higher exposure. That is a food-supply problem, not a people problem.¹

An earlier study from the same research group found that higher intake of ultra-processed foods, added sugars, and refined grains predicted higher urinary ZEN in a Rochester, New York pregnancy cohort.⁶ Two independent cohorts, two convergent answers.

Does It Actually Reach the Baby?

This is the question that matters, and it is where I want to be scrupulously careful, because the honest answer has more nuance than the headlines allow.

The Placenta Is Not a Wall

Generations of physicians were taught that the placenta functions as a protective barrier. It does not. It functions as an exchange surface, and chemicals cross it. We have direct human tissue evidence for this across multiple toxin classes:

• Mycoestrogens are in placental tissue. In the UPSIDE cohort in Rochester, New York, mycoestrogens were measured directly in 271 placentas and detected in 84 percent of them.⁷
• Aflatoxins cross. Work summarized in a 2021 review found aflatoxin levels above 20 ppb in 74.1 percent of amniotic fluid samples, 67.2 percent of neonatal cord blood samples, and 62.4 percent of maternal venous blood samples in an exposed population.⁸
• Ochratoxin A crosses. A biomonitoring study in rural Burkina Faso detected OTA in more than half of maternal blood samples and in 38.3 percent of newborns within 12 hours of birth.⁹
• Microplastics accumulate there. Researchers at the University of New Mexico measured microplastics in all 62 human placentas they tested, at concentrations of 6.5 to 790 micrograms per gram of tissue, with polyethylene accounting for 54 percent of the total. What makes this striking is the timeline: the placenta is an organ that has only existed for about eight months.^10,11 A 2025 analysis of 175 placentas presented at the Society for Maternal-Fetal Medicine found significantly higher micro- and nanoplastic concentrations in preterm placentas than in term placentas.¹²
• Herbicide residues are nearly universal. In an Indiana birth cohort, more than 90 percent of pregnant women had detectable urinary glyphosate, and higher levels correlated with shortened gestational length.¹³

What the Birth Outcome Data Show, and What They Do Not

The 2025 Environmental Health Perspectives study from the Rutgers group is the most important paper on this question, and it deserves precision rather than a headline.⁷

Overall, the association between placental mycoestrogens and birth weight was inverse but not statistically significant. I want to say that clearly, because I have seen this study summarized as “mold toxins lower birth weight,” and that overstates it.

What the researchers actually found was more interesting, and in some ways more important. They stratified by a genetic variant, ABCG2 C421A, also called Q141K, which codes for BCRP, the placental efflux transporter that pumps xenobiotics back out of fetal circulation. Among the roughly 17 percent of participants carrying the reduced-function variant, total mycoestrogens were associated with lower birth weight. Among those with normal transporter function, mycoestrogens were associated with heavier placentas and a reduced fetoplacental weight ratio, a marker of reduced placental efficiency. Effects also differed by infant sex.⁷

This is precision environmental medicine. The exposure was not uniformly harmful. It was harmful to the subgroup whose detoxification machinery could not keep up.

That finding maps precisely onto what I see clinically. Two women live in the same water-damaged home, eat the same food, drink the same water. One is fine. One is profoundly ill. The difference is rarely the exposure. It is almost always the capacity to clear it, shaped by genetics, nutrient status, gut integrity, bile flow, and total cumulative burden.

Additional work from the same cohort has associated urinary mycoestrogens with greater gestational weight gain¹⁴ and with sex-specific differences in maternal serum and cord blood sex steroid hormones.¹⁵ These are associations, from observational cohorts, in modest sample sizes. They are signals worth acting on prudently. They are not proof of causation, and I will not present them as such.

The Regulatory Gap

Here is what genuinely concerns me as a physician.

The European Commission has established maximum permitted levels for zearalenone in cereals, baked goods, and specifically in infant and young child foods, along with guidance values for animal feed.¹⁶ The United States has not. The FDA added zearalenone to its Mycotoxin Compliance Program, but no maximum allowable limits in food have been established, and the surveillance that exists was never designed to characterize population-level exposure.¹

Meanwhile, in U.S. testing, zearalenone has been detected in raw corn at a mean of 39.8 micrograms per kilogram with more than 80 percent of samples positive, with higher concentrations in wet-milling byproducts such as corn gluten and corn germ, which flow directly into processed foods and animal feed.¹

So we have a potent estrogen receptor agonist, in the food supply, at measurable levels, reaching 100 percent of tested pregnant women, with no enforceable limit. That is not a reason for panic. It is a reason for informed personal action while the regulatory science catches up.

What Actually Reduces Exposure: An Honest Evidence Ranking

I am going to separate what we know from human intervention data, what we know from mechanistic and laboratory work, and what remains sensible extrapolation. My patients deserve that distinction, and so do you.

Practical Steps I Give to Women Planning Pregnancy

1. Front-load the work before conception. This is the single most important thing I can tell you. The window where aggressive detoxification support is both safe and useful is preconception, ideally three to six months before you try. Mobilizing stored toxins during pregnancy is not a good idea, and I will explain why below.
2. Reduce ultra-processed corn and grain products. Not eliminate corn. Reduce the highly processed, long-shelf-life, wet-milling-derived category: chips, crackers, cereal bars, extruded snacks, and anything with corn gluten or corn germ derivatives on the label.
3. Choose organic where it counts. Grain and corn products are worth prioritizing, since these are the crops where both mycotoxin and pesticide exposure concentrate.
4. Store grains and nuts properly. Cool, dry, sealed. Refrigerate or freeze nuts, cornmeal, and whole-grain flours. Fusarium and Aspergillus proliferate in warm, humid pantries.
5. Eat cruciferous vegetables daily. Broccoli sprouts, broccoli, arugula, cabbage, kale, watercress. This is one of the few interventions supported by randomized human trial data for enhancing phase II detoxification.
6. Support the gut and bile. Mycotoxins recirculate enterohepatically. Adequate fiber, healthy bile flow, and a well-populated microbiome matter more than any single supplement.
7. Address your home first. Food is one route. Water-damaged buildings are another, and often the larger one. If you have unexplained symptoms, please read my article on mold, mycotoxins, and immune dysfunction and consider whether your building is contributing.

A CLINICAL CAUTION I WANT TO BE VERY CLEAR ABOUT

Pregnancy and lactation are not the time for aggressive detoxification protocols. Mobilizing stored lipophilic toxins raises circulating levels before they are eliminated, and the fetus and nursing infant have no way to opt out of that redistribution. Binders can also interfere with the absorption of prenatal vitamins, iron, and medications. During pregnancy, the strategy is avoidance and nourishment, not mobilization. Save the deeper detoxification work for preconception or after weaning, and do it with a qualified physician who knows your full clinical picture. Nothing in this article replaces the guidance of your obstetrician or midwife.

Where Supplementation Fits (Preconception and Postpartum)

In my practice, the preconception window is where I do the real work. These are the formulations I most often reach for, and I want to name plainly that these are my own physician-formulated products, so you should weigh that accordingly.

• Dr. Jill Health® Glutathione Essentials provides reduced glutathione, the master antioxidant that mycotoxin exposure depletes. For those with higher toxic burden, Liposomal Glutathione offers better cellular delivery.
• Dr. Jill Health® Liver Essentials combines N-acetyl-cysteine, alpha-lipoic acid, milk thistle, and selenium to support phase I and phase II liver pathways, which is precisely where zearalenone is conjugated and prepared for excretion.
• MycoPul® uses multiple targeted binders, including purified zeolite clinoptilolite, to capture mycotoxins in the GI tract before they recirculate. Bind-Aid Universal Toxin Binder is my broad-spectrum option. Both are preconception and post-lactation tools, not pregnancy tools.
• Probiotic Daily Essentials or Probiotic Essentials with Saccharo support the microbial ecology that helps sequester mycotoxins in the gut and maintains the barrier integrity these toxins erode.
• For a comprehensive preconception reset in someone with confirmed mold exposure, Dr. Jill’s Miracle Mold Detox Box sequences drainage support, liver pathways, mitochondrial recovery, and binding into a structured 30-day protocol.

You can explore the full formulary at drjillhealth.com.

Related Reading From My Blog

• Mycotoxins: The Hidden Danger Lurking In Your Kitchen, on dietary mycotoxin exposure and food storage
• Mycotoxins: How These Invisible Toxins Are Wreaking Havoc on the Gut, on intestinal barrier damage
• Mold, Mycotoxins, and Your Immune System, on immune dysregulation and a step-by-step recovery framework
• Mold and Your Brain, on neuroinflammation and the amygdala
• Breathing the Office Air, on occupational and building-related exposure
• The Next Generation of Mold Detox, on a comprehensive testing and treatment approach

What I Want You to Take From This

If you are pregnant right now and reading this with a knot in your stomach, please hear me.

You did not fail. You ate food from a food supply that has no enforceable limit on this contaminant. That is a systems failure, not a maternal one. The exposures measured in these studies are low. The health associations that exist are modest, mostly observational, and concentrated in genetically susceptible subgroups. Nobody in this literature is saying that eating a corn tortilla harmed your baby.

What this research does tell us is that the tools of exposure science have finally caught up to a question functional medicine has been asking for two decades: what is the cumulative burden, and who can clear it? The answers are arriving. They point toward food quality, toward the gut, toward glutathione and bile and transporter function, and toward the preconception window as the place where preparation pays.

Fear is a terrible clinician. It makes women anxious about the food on their plate at the exact moment they most need nourishment and peace. Information, held gently, is different. It lets you make a handful of specific changes and then set the worry down.

There is a moment in nearly every appointment where the science runs out and something else has to carry the weight. A mother asks me if her baby will be alright, and the truthful answer is that I do not know everything, and neither does the literature.

What I have come to believe, through my own illness and through twenty years of sitting with people in the unbearable middle of theirs, is that we are not asked to control every variable. We are asked to be faithful with the ones in front of us. Choose the better food. Fix the leaking roof. Take the supplement. Then release the rest.

Julian of Norwich wrote from a plague-scarred England that all shall be well. She was not denying the danger. She was refusing to let it have the final word. I pray that over every woman carrying a child while reading a study like this one: that you would do the next right thing, and then rest in a love that is holding both of you more securely than any protocol ever could.

References

1. Rivera-Núñez Z, Kinkade CW, Juenke A, et al. Diet and mycoestrogen exposure in a pregnancy cohort: the Jersey Babies pilot study. J Expo Sci Environ Epidemiol. 2026. doi:10.1038/s41370-026-00940-0
2. Marin S, Ramos AJ, Cano-Sancho G, Sanchis V. Mycotoxins: occurrence, toxicology, and exposure assessment. Food Chem Toxicol. 2013;60:218-237. doi:10.1016/j.fct.2013.07.047
3. Kuiper-Goodman T, Scott PM, Watanabe H. Risk assessment of the mycotoxin zearalenone. Regul Toxicol Pharmacol. 1987;7(3):253-306. doi:10.1016/0273-2300(87)90037-7
4. Frizzell C, Ndossi D, Verhaegen S, et al. Endocrine disrupting effects of zearalenone, alpha- and beta-zearalenol at the level of nuclear receptor binding and steroidogenesis. Toxicol Lett. 2011;206(2):210-217. doi:10.1016/j.toxlet.2011.07.015
5. Warth B, Sulyok M, Berthiller F, Schuhmacher R, Krska R. New insights into the human metabolism of the Fusarium mycotoxins deoxynivalenol and zearalenone. Toxicol Lett. 2013;220(1):88-94. doi:10.1016/j.toxlet.2013.04.012
6. Kinkade CW, Brinker A, Buckley B, et al. Sociodemographic and dietary predictors of maternal and placental mycoestrogen concentrations in a US pregnancy cohort. J Expo Sci Environ Epidemiol. 2024;35:382-392.
7. Rivera-Núñez Z, Kinkade C, Brinker A, et al. Mycoestrogen exposure during pregnancy: impact of the ABCG2 Q141K variant on birth and placental outcomes. Environ Health Perspect. 2025;133(5):057001. doi:10.1289/EHP14478
8. The presence of mycotoxins in human amniotic fluid. Toxins (Basel). 2021;13(6):409, summarizing earlier amniotic fluid and cord blood aflatoxin findings. doi:10.3390/toxins13060409
9. Assessment of maternal exposure to mycotoxins during pregnancy through biomarkers in fetal and neonatal tissues. Toxins (Basel). 2025;17(10):518. doi:10.3390/toxins17100518
10. Garcia M, Campen MJ, et al. Quantitation and identification of microplastics accumulation in human placental specimens. Toxicological Sciences. February 2024. See also: University of New Mexico Health Sciences summary
11. Ragusa A, Svelato A, Santacroce C, et al. Plasticenta: first evidence of microplastics in human placenta. Environ Int. 2021;146:106274. PMID 33395930
12. Society for Maternal-Fetal Medicine. High concentrations of plastics in the placentae of infants born prematurely. The Pregnancy Meeting, 2025.
13. Parvez S, Gerona RR, Proctor C, et al. Glyphosate exposure in pregnancy and shortened gestational length: a prospective Indiana birth cohort study. Environ Health. 2018;17:23. doi:10.1186/s12940-018-0367-0
14. Kinkade CW, Rivera-Núñez Z, Brinker A, et al. Urinary mycoestrogens and gestational weight gain in the UPSIDE pregnancy cohort. Environ Health. 2024;23:103. doi:10.1186/s12940-024-01141-8
15. Kinkade CW, Aleksunes LM, Brinker A, et al. Associations between mycoestrogen exposure and sex steroid hormone concentrations in maternal serum and cord blood in the UPSIDE pregnancy cohort. Int J Hyg Environ Health. 2024;260:114405. doi:10.1016/j.ijheh.2024.114405
16. European Union. Commission Regulation 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food. EUR-Lex
17. Fagan J, Bohlen L, Patton S, Klein K. Organic diet intervention significantly reduces urinary glyphosate levels in U.S. children and adults. Environ Res. 2020;189:109898. PMID 32797996
18. Oates L, Cohen M, Braun L, Schembri A, Taskova R. Reduction in urinary organophosphate pesticide metabolites in adults after a week-long organic diet. Environ Res. 2014. PMID 24769399
19. Kensler TW, Chen JG, Egner PA, et al. Effects of glucosinolate-rich broccoli sprouts on urinary levels of aflatoxin-DNA adducts and phenanthrene tetraols in a randomized clinical trial in He Zuo township, Qidong, China. Cancer Epidemiol Biomarkers Prev. 2005;14(11):2605-2613. PMID 16284385
20. Egner PA, Chen JG, Zarth AT, et al. Rapid and sustainable detoxication of airborne pollutants by broccoli sprout beverage: results of a randomized clinical trial in China. Cancer Prev Res (Phila). 2014;7(8):813-823.
21. Chlebicz A, Sliżewska K. In vitro detoxification of aflatoxin B1, deoxynivalenol, fumonisins, T-2 toxin and zearalenone by probiotic bacteria from genus Lactobacillus and Saccharomyces cerevisiae yeast. Probiotics Antimicrob Proteins. 2019. doi:10.1007/s12602-018-9512-x
22. Krausová M, Ayeni KI, Gu Y, et al. Longitudinal biomonitoring of mycotoxin exposure during pregnancy in the Yale Pregnancy Outcome Prediction Study. Environ Int. 2024;194:109081. doi:10.1016/j.envint.2024.109081
23. Kinkade CW, Rivera-Núñez Z, Gorczyca L, Aleksunes LM, Barrett ES. Impact of Fusarium-derived mycoestrogens on female reproduction: a systematic review. Toxins (Basel). 2021;13(6):373.
24. Duarte S, Silva LJG, Pereira A, et al. Mycotoxins exposure in Cabinda, Angola: a pilot biomonitoring survey of breastmilk. Toxins (Basel). 2022;14(3):204.
25. Vin K, Rivière G, Leconte S, et al. Dietary exposure to mycotoxins in the French infant total diet study. Food Chem Toxicol. 2020;140:111301. doi:10.1016/j.fct.2020.111301
26. Bandera EV, Chandran U, Buckley B, et al. Urinary mycoestrogens, body size and breast development in New Jersey girls. Sci Total Environ. 2011;409(24):5221-5227. doi:10.1016/j.scitotenv.2011.09.029
27. Zhang S, Zhou S, Gong YY, Zhao Y, Wu Y. Human dietary and internal exposure to zearalenone based on a 24-hour duplicate diet and following morning urine study. Environ Int. 2020;142:105852. doi:10.1016/j.envint.2020.105852
28. Rutgers University. In pilot study, researchers find estrogen-like contaminant in every pregnant participant tested. Rutgers Today. July 21, 2026.

Jill C. Carnahan, MD, ABIHM, ABoIM, IFMCP is a triple board-certified functional medicine physician and Medical Director of Flatiron Functional Medicine in Louisville, Colorado, where she specializes in mold and mycotoxin illness, chronic inflammatory response syndrome, mast cell activation, complex chronic infection, and environmental toxicity. She is the author of the bestselling book Unexpected: Finding Resilience through Functional Medicine, Science, and Faith, host of Resiliency Radio, and is featured in the documentary Doctor/Patient. Learn more at jillcarnahan.com and follow her @DrJillCarnahan on Instagram.

This article is for educational purposes only and does not constitute medical advice, diagnosis, or treatment. It is not a substitute for care from your obstetrician, midwife, or personal physician. Do not begin, stop, or change any supplement or medication during pregnancy or lactation without consulting your prenatal care provider. Statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease. Dr. Carnahan is the founder and formulator of Dr. Jill Health® products referenced in this article and receives compensation from their sale.