Research Results
Beta Version
Use the search bar below to find studies, or apply one or more filters to narrow your results. See our list of keywords to guide your search.
Search by keyword
Select
Select
- All Risk Factors
- Air Pollution
- Alcohol
- Antimicrobials
- Artificial sweeteners
- Bisphenols
- Body Weight
- Breast Density
- Chemical Mixtures
- Chemicals in products
- Cleaning Products
- Diet
- Exercise
- Family History
- Furniture & Electronics
- Genetics
- Gut Health
- Hair Dye
- Hormones
- Inflammation
- Job
- Light at night
- Metals
- Neighborhood
- Night Shift Work
- Noise
- Non-stick Pans & Waterproof Gear
- Oral Contraceptives
- PAHs
- Parabens
- PCBs
- Personal Care Products
- Pesticides
- PFAS
- Pharmaceuticals
- Place-based
- Plastic
- Pregnancy & Breastfeeding
- Processed Food
- Puberty Age
- Race/Ethnicity
- Radiation
- Red meat
- Scented Products & Soft Plastic
- Sleeping Patterns
- Soda
- Stress
- Sugar
- Sunscreen
- Tobacco
- Vitamin D
Select
Select
Select
Select
Select the Chemical Agents
- All Chemical Agents
- 1,1,2,2-TCA
- 1,3-Butadiene
- Acrolein
- Aldrin
- Alkylphenols
- Antimicrobials
- Antimicrobials: QACs, Triclosan, Triclocarban
- Aromatic Amines
- Arsenic
- Artificial Sweeteners
- Atrazine
- Benzene
- Bisphenols
- Cadmium
- Chlordane
- Chlorpyrifos
- DDT
- Dibutyl Phthalate
- Dichlorvos
- Dieldrin
- Dioxins
- ell/
- Ethanol (alcohol)
- Ethyl Benzene
- Ethylene Oxide
- Flame Retardants
- Food
- Formaldehyde
- Glyphosate
- Heptachlor
- Hormones
- Insulin
- Lead
- Light at Night
- Mercury
- Metals
- Methoxyclor
- Naphthalene
- Night Shift Work
- Nitrogen Dioxide
- Noise
- Oral Contraceptives
- Organochlorine Pesticides
- Organophosphate Pesticides
- Ozone
- PAHs
- Parabens
- Particulate Matter
- PCBs
- Pesticides
- PFAS
- Phenols
- Phthalates
- Processed Food
- PVC
- Radiation: Ionizing
- Radiation: Non-Ionizing
- Soda
- Stress
- Sugar
- Tobacco
- Toluene
- Trichloroethylene
- Triclosan
- Ultraviolet Radiation
- UV Filters
- Vinyl Chloride
Select the Study Tags
Sort By
- Relevance
- Title (A to Z)
- Title (Z to A)
- Publication Year (Ascending)
- Publication Year (Descending)
- Authors (A to Z)
- Authors (Z to A)
2025
Ecotoxicol Environ Saf
This study analyzed six xenoestrogens (hormone-disrupting chemicals including phthalates, BPA, and alkylphenols) in atmospheric particles at a university campus in China from 2021 to 2023. BPA was the most prevalent xenoestrogen detected, with concentrations of these chemicals being significantly higher in winter than summer, and the overall cancer and non-cancer health risks were below threshold limits for the general population. However, infants and young children showed significantly higher risk values compared to other age groups, indicating they face greater health risks from atmospheric exposure to these endocrine disruptors. The research provides important data for developing policies to reduce health risks from airborne xenoestrogen exposure, particularly for vulnerable populations like children.
2025
Sci Total Environ
This review examines the relationship between DEHP (a common plastic additive) and cancer development, noting that while epidemiological studies suggest a link between DEHP exposure and increased cancer risk, the specific mechanisms need further clarification. The research shows that DEHP influences multiple aspects of cancer biology, including cell growth, spread, and drug resistance, through various molecular pathways involving hormone receptors, inflammation, and genetic modifications. DEHP’s carcinogenic effects operate through complex mechanisms including PI3K/AKT signaling, estrogen receptor activation, and oxidative stress. Understanding these molecular pathways could help develop targeted strategies to prevent and treat cancers associated with DEHP exposure.
2024
Sci Total Environ
This large prospective cohort study investigated the association between DEHP exposure and breast neoplasms in 273,295 women from the UK Biobank, using modeled DEHP levels from environmental data and Cox regression analysis. Results showed that higher baseline and long-term DEHP exposure was positively associated with increased risk of malignant neoplasm, carcinoma in situ, and benign breast neoplasms, with suggestive higher risk in younger women and oral contraceptive users.
2024
Environ Health Perspect
A nationwide study using CDC biomonitoring data found that California’s Proposition 65, which requires warnings about chemicals that cause cancer or reproductive harm, led to reduced exposures to listed chemicals across the entire United States, not just California. While blood and urine concentrations of 37 monitored chemicals generally declined over time, the researchers found evidence of problematic chemical substitution—for example, after bisphenol A (BPA) was listed, its concentrations dropped 15% but levels of the unlisted substitute bisphenol S (BPS) increased 20%. Californians generally had lower levels of harmful chemicals in their bodies compared to residents of other states, suggesting the law had additional protective effects. The findings indicate that transparency laws like Prop 65 can drive manufacturers to reformulate products nationwide, but regulations need to address entire chemical classes rather than individual substances to prevent companies from simply switching to similar but unlisted toxic chemicals.
2022
Cancer Epiemiol
The first Indian case-control study examining phthalates (chemicals widely used in plastics, cosmetics, and food packaging) and breast cancer found that women with higher urinary levels of di-butyl phthalate (DBP) had 1.5 times increased breast cancer risk, while those with higher DEHP levels had nearly 3 times increased risk. Analysis of breast tumor tissue revealed mutations in several genes known to respond to phthalate exposure, affecting pathways involved in hormones, metabolism, and cancer development. These findings suggest that exposure to certain phthalates may increase breast cancer risk through genetic changes, though larger studies are needed to confirm these results and understand how early-life exposures might contribute to cancer development later in life.
2022
Crit Rev Food Sci Nutr
A systematic review of 131 epidemiological studies examining endocrine-disrupting chemicals (EDCs) and breast cancer risk found evidence that exposure to various EDCs—including pesticides (DDT/DDE, atrazine, dioxin), synthetic chemicals (BPA, phthalates, PFAS, PCBs, PBDEs), and other compounds found in everyday products—may elevate breast cancer risk, particularly when exposure occurs during early life. The review identified food as a major route of EDC exposure and emphasized that because most EDCs persist in the environment and accumulate in the body over time, long-term multi-generational health impacts need to be assessed. The authors call for improved exposure assessments of EDCs in food and food packaging, along with careful evaluation of their links to breast cancer development to inform policy-making and regulations aimed at protecting public health.
2022
Chemosphere
Researchers measured 41 endocrine-disrupting chemicals (EDCs) in women living in the Greater Manila Area, Philippines, comparing those with and without breast cancer. They found that certain perfluoroalkyl substances (PFAS) were significantly associated with breast cancer, with some chemicals showing dramatically increased risk: PFDoA was associated with a 1,263% increased risk, PFDA with an 826% increased risk, and PFHxA with a 166% increased risk. Long-chain PFAS levels were higher in women from heavily industrialized areas compared to the National Capital Region. This study provides the first baseline data on EDC exposure levels in Filipino women, filling a critical gap in knowledge about chemical exposures in Southeast Asian populations and suggesting that industrial pollution may be contributing to elevated PFAS levels and breast cancer risk.
2019
J Clin Oncl
This large-scale Danish nationwide study followed 1.12 million women over nearly 10 million woman-years to examine the relationship between phthalate exposure from prescription medications and breast cancer risk. The researchers tracked phthalate exposure by linking a database of drug ingredients with prescription records, finding that most phthalate exposures were not associated with increased breast cancer risk. However, high-level cumulative exposure to dibutyl phthalate (≥10,000 mg) was associated with approximately double the risk of estrogen receptor-positive breast cancer, consistent with laboratory evidence showing this compound has estrogenic effects. The study concludes that women should avoid high-level dibutyl phthalate exposure, particularly through long-term use of pharmaceuticals containing this compound, though lower exposure levels did not increase breast cancer risk.
2018
Cancer Epidemiol Biomarkers Prev
This study examined how exposure to endocrine-disrupting chemicals (EDCs) during puberty affects breast tissue development in 200 Chilean girls by measuring urinary concentrations of phenols and phthalates at two stages of breast development and assessing breast density. The researchers found that certain phthalate metabolites were associated with increased breast density measures – specifically, higher levels of monocarboxyisooctyl phthalate were linked to 7% higher percent dense breast tissue, and monoethyl phthalate was associated with increased fibroglandular volume. Bisphenol A showed a U-shaped relationship with fibroglandular volume, where girls with middle-level exposures had at least 10% lower fibroglandular volume compared to those with low or high exposures. The findings suggest that developing breast tissue is vulnerable to certain EDCs during childhood and adolescence, which may have implications for future breast cancer risk since breast density is a known risk factor.
2018
Environ Health
This longitudinal study examined how exposure to endocrine disrupting chemicals (EDCs) affects the timing of menarche in Chilean girls by measuring 26 phenol and phthalate compounds in urine samples collected before breast development and during adolescence. The researchers found that different chemicals had varying effects depending on when exposure was measured: higher early exposure to DEHP was associated with later menarche, while early exposure to certain phenols and later exposure to some phthalates were linked to earlier menarche. The study also revealed that body weight influenced these effects, with overweight or obese girls showing earlier menarche when exposed to higher levels of certain chemicals like triclosan, while normal-weight girls did not show this association. These findings demonstrate that specific EDCs can disrupt normal sexual development in girls, with timing of exposure and body weight being important factors.
2025
J Hazard Mater
This study investigated whether DEHCH, a newly developed alternative plasticizer, has safer endocrine-disrupting effects compared to conventional phthalates and other alternative plasticizers using computer modeling, cell studies, and zebrafish testing. The researchers found that DEHCH showed lower binding affinity to hormone receptors and did not affect hormone-related gene expression or neurosteroid levels in zebrafish, unlike the other tested plasticizers. In contrast, conventional phthalates (DEHP, DINP) and previously proposed alternatives (DINCH, DEHTP) caused hyperactivity in zebrafish and altered hormone-related gene expression and neurosteroid concentrations. The results suggest that DEHCH may be a safer alternative to both conventional phthalates and previously proposed substitutes in terms of endocrine disruption and neurological effects.
2025
J Hazard Mater
This study used advanced computer modeling to assess the combined reproductive health risks of phthalates (PAEs) and organophosphates (OPEs) found in atmospheric particles, focusing on their ability to disrupt hormone receptors. The researchers found that the mixed toxicity of these compounds was lower than expected from individual effects, suggesting they may interfere with each other’s toxic actions through antagonistic effects. Using network analysis and molecular modeling, they identified 590 potential targets and 50 core targets (including hormone receptors) affected by these pollutants, with DEHP, TPHP, and MEHP being key disruptors of hormone signaling pathways. The study also identified two previously overlooked targets (AKT1 and HSP90AA1) that may be important for reproductive toxicity, providing new insights into how these atmospheric pollutants may affect human reproductive health.
2025
Int J Hyg Environ Health
New research highlights the link between endocrine-disrupting chemicals (EDCs) and earlier breast development in girls. A systematic review of 68 studies found that 10 out of 14 high-quality studies linked prenatal and postnatal exposure to EDCs like organohalogenated compounds and phthalates to earlier thelarche. With thelarche now occurring nearly three months earlier per decade, these findings raise serious concerns about long-term health risks, including breast cancer. Reducing exposure to harmful chemicals in everyday products is crucial to protecting hormonal health and preventing early puberty.
2025
Int J Environ Sci
This study investigated how DEHP (a common plastic additive) affects triple-negative breast cancer (TNBC), the most aggressive form of breast cancer. The researchers found that prolonged DEHP exposure enhanced cancer cell migration and invasion both in laboratory cultures and in animal models by activating a specific protein pathway involving MSI2, which promotes cancer spread and stem cell-like properties. DEHP exposure also reduced levels of a protective microRNA (miR-155-5p), while increasing MSI2 expression, suggesting these molecules work in opposition to each other. The findings identify MSI2 as a potential therapeutic target and prognostic marker for TNBC patients, providing new insights into how plastic additives may contribute to cancer metastasis.
2025
Environ Pollut
This study examined the combined toxic effects of nanoplastic particles (NPs) and DEHP plasticizer on mouse mammary epithelial cells, finding that co-exposure caused severe cell death (pyroptosis), inflammation, and oxidative stress. The researchers discovered that the combination damaged mitochondria and increased endoplasmic reticulum stress, leading to disrupted cellular energy production and membrane integrity. Notably, co-exposure enhanced communication between cellular organelles (ER-mitochondria crosstalk), involving increased calcium levels and expanded contact areas between these structures. The findings reveal new molecular mechanisms by which plastic particles and plasticizers can work together to damage mammary gland tissue, providing insights into potential breast health risks from environmental plastic pollution.
2025
Ecotoxicol Env Saf
A Mendelian randomization study using genetic data from European populations found that specific endocrine-disrupting chemicals (EDCs) were causally associated with different breast cancer subtypes: n-butyl paraben (n-BuP) increased Luminal A risk, mono-methyl phthalate decreased Luminal B risk, and mono-iso-butyl phthalate (MiBP) increased triple-negative breast cancer risk. Mediation analysis revealed that blood metabolites—including caffeic acid sulfate and caffeine metabolism ratios—partially explained the n-BuP effect on Luminal A, while methylsuccinate mediated the MiBP effect on triple-negative cancer, and epigenetic analysis identified specific DNA methylation sites associated with EDC exposure and breast cancer risk. These findings provide the first genetic evidence suggesting causal relationships between specific EDC exposures and breast cancer subtypes through distinct metabolic and epigenetic pathways, identifying potential biomarkers for early detection and highlighting the heterogeneous effects of different EDCs on breast cancer biology—underscoring the need for chemical-specific and subtype-specific prevention strategies rather than treating all EDCs or breast cancers as uniform entities.
2025
Sci Totl Environ
This study investigated the effects of three common plastic additives (DEHP, BPA, and benzotriazoles) on Atlantic cod liver tissue using precision-cut liver slices exposed to various concentrations of these chemicals individually and in mixtures. The researchers found that BPA and chemical mixtures caused estrogenic effects, significantly increasing vitellogenin (a female egg protein) production and related gene expression in male juvenile cod. The study also observed changes in liver metabolism genes, with mixture exposures showing potentially different effects than individual chemical exposures. The results suggest these plastic additives can disrupt hormone systems in fish, with BPA being the primary driver of estrogenic effects, though the interaction effects between chemicals require further investigation.
2024
Environ Int
A study of 1,031 pregnant women from the socioeconomically diverse CANDLE cohort in the urban South found that ultra-processed foods constituted 38.6% of participants’ diets on average, with each 10% higher dietary proportion of ultra-processed foods associated with 13.1% higher urinary concentrations of DEHP phthalate metabolites, while specific foods like hamburgers, French fries, soda, and cake showed 6-10.5% higher DEHP per standard deviation increase in consumption. Causal mediation analyses revealed that lower income and education levels were associated with 1.9% and 1.4% higher DEHP exposure respectively, mediated through increased ultra-processed food consumption, indicating that ultra-processed foods contribute to socioeconomic disparities in phthalate exposure during pregnancy. The findings demonstrate that consuming ultra-processed foods increases exposure to endocrine-disrupting phthalates from food contact materials, and because socioeconomic barriers can prevent dietary modifications, policies to reduce phthalates in food packaging and processing are needed rather than relying solely on individual dietary recommendations to reduce prenatal phthalate exposures.
2024
Environ Res
Endocrine Disrupting Chemicals (EDCs)—including bisphenol A, phthalates, parabens, pesticides, and heavy metals commonly found in pharmaceuticals, cosmetics, and packaging—are widespread environmental pollutants that interfere with the body’s hormone system. Research shows EDCs have harmful effects on women’s reproductive health, contributing to conditions such as endometriosis, polycystic ovary syndrome, uterine fibroids, premature ovarian failure, menstrual irregularities, and infertility. This review emphasizes the need for healthcare professionals to consider environmental exposures when evaluating patients, highlights potential mechanisms by which EDCs affect female reproduction, and discusses how nutritional interventions and stricter environmental regulations could help reduce EDC-related health risks. Understanding the link between EDCs and women’s health is crucial for developing protective strategies, informing treatment approaches, and shaping public policies to safeguard reproductive and overall well-being. The study seeks to advise that couples attempting to conceive should avoid endocrine disrupting chemicals (EDCs) such as BPA, pesticides, and phthalates. Following this advice is found to be crucial during the prenatal and periconceptional periods, where fetal development and growth are critical in this window.
2024
Environ Health Perspect
A mouse study examining DNA methylation changes from lead and DEHP (phthalate) exposure during pregnancy and early development found that the brain (cerebral cortex) showed the most epigenetic changes (66% for lead, 57% for DEHP), with alterations concentrated in gene regulatory regions that control gene expression. The research identified imprinted genes—particularly Gnas and Grb10—as targets of both chemical exposures across multiple tissues, with some DNA methylation signatures in blood matching those in target organs like liver and brain, suggesting blood tests could potentially detect toxic exposures affecting other organs. Notably, lead exposure caused consistent hypermethylation of the Grb10 gene’s control region in both blood and liver of male offspring, providing preliminary evidence that epigenetic changes in easily accessible blood samples might serve as biomarkers for chemical exposures affecting critical organs like the brain. These findings are significant for breast cancer prevention because early-life exposures to lead and phthalates can alter epigenetic programming in ways that may increase disease risk decades later, and identifying blood-based biomarkers could enable early detection of harmful exposures during vulnerable developmental windows.
2024
PNAS
This study examined the health impacts of three major plastic-associated chemicals—BPA, DEHP, and PBDEs—across 38 countries representing one-third of the global population. The researchers found that in 2015, these chemicals were linked to approximately 5.4 million cases of heart disease, 346,000 strokes, 164,000 deaths among older adults, and 11.7 million lost IQ points in children due to prenatal exposure. The total economic cost of these health impacts was estimated at $1.5 trillion. The study suggests that if exposure levels had been reduced earlier, hundreds of thousands of deaths and millions of IQ points could have been prevented.
2024
BMC Pub Health
This study used NHANES 2011–2018 data (n = 6,147) to evaluate the association between DEHP exposure and cancer risk. After adjusting for confounders, DEHP and its metabolites were significantly associated with increased risk of overall cancer prevalence, especially female reproductive system cancers (OR > 1.0, p < 0.05).
2024
Environ Int
A study in mice found that exposure to DEHP—a common chemical used to make plastics flexible—disrupts the gut-mammary connection, causing changes in gut bacteria, intestinal inflammation, and direct damage to mammary (breast) tissue that could impair milk production. DEHP altered gut microbiome composition (increasing some bacteria while decreasing others), changed blood metabolite levels, and its breakdown product (MEHP) triggered cell death in mammary tissue through multiple pathways. These findings raise concerns about DEHP exposure from plastics affecting both human breast health and dairy production in livestock, while identifying potential therapeutic targets to counteract the chemical’s harmful effects on the gut-breast axis.
2024
Environ Sci Technol
A study of 751 reproductive-aged Black women found that the relationship between personal care product (PCP) use and exposure to endocrine-disrupting chemicals (EDCs) varied significantly by socioeconomic status (SES), with different patterns of chemical exposure from the same products depending on women’s education, income, and employment. For example, vaginal powder use was associated with higher phenol exposure (a class of EDCs) among lower SES women but showed no such association in higher SES women, suggesting that product formulations, brands, or usage patterns may differ across SES groups. These findings highlight that Black women face inequitable EDC exposures that are influenced by both race and socioeconomic factors, underscoring the need for targeted public health interventions that address these intersecting disparities in chemical exposures from everyday products
2023
Chemosphere
A community-based intervention study (REDUXE) examined the effects of discontinuing paraben and phthalate-containing personal care products over 28 days by collecting paired fine needle aspirates of breast tissue from healthy volunteers before and after intervention, finding striking reversal of cancer-associated phenotypes including PI3K-AKT/mTOR pathway alterations, autophagy, and apoptotic signaling networks, along with significant reductions in urinary paraben and phthalate metabolites. Post-intervention breast tissue showed “normalizing” changes in estrogen-modulated gene expression pathways, estrogen receptor alpha:beta ratios, and cell cycle S-phase fraction when treated with 17β-estradiol in vitro, demonstrating functional improvement in cellular responses. This paradigm-shifting study reveals that persistent exposure to xenoestrogens from daily-use personal care products produces unfavorable pro-carcinogenic cellular changes in human breast tissue that can be reversed through short-term avoidance, suggesting that reducing xenoestrogen exposure from consumer products may suppress cancer-promoting phenotypes and represents a viable approach for breast cancer prevention.
2023
Compr Rev Food Sci Food Saf
A systematic review of phthalate contamination in food identified 19 phthalates across multiple food categories, with 57 measurements exceeding legal limits and DEHP showing the highest incidence; risk assessment revealed high probability of exceeding tolerable daily intake for DEHP and DBP in fish, oils/fats, cereals, and dairy for both children and adults, with fats/oils being the most critical category. Migration from food contact materials is positively correlated with temperature, contact time, fat content, and acidity, with contamination occurring throughout the production chain. The widespread contamination exceeding safe exposure limits—particularly for vulnerable populations including children—highlights the urgent need for stricter regulation of phthalates in food packaging and production materials.
2023
Frontiers
This meta-analysis aimed to evaluate the association between exposure to endocrine-disrupting chemicals (EDCs), including phthalates and other common environmental pollutants, and breast cancer risk. The study found that certain EDCs—such as p,p′-DDT, chlordane, HCH, and specific PCBs—were positively associated with increased breast cancer risk, while a few compounds like BBP and PFDoDA showed a negative association.
2023
Endocrinol Metab Clin North Am
Multiple social and structural determinants of health undoubtedly contribute to the marked racial/ethnic-, gender-, and socioeconomic-based disparities in endocrine health; however, the contribution of environmental injustice is vastly underappreciated. Indeed, those groups disproportionately burdened by endocrine disorders are often exposed to higher levels of various EDCs, including PCBs, phthalates, bisphenols, OC pesticides, air pollutants, PFASs, toxic metals/metalloids, and BFRs. These chemicals threaten our reproductive and metabolic health, contributing to diabetes prevalences, obesity, and disorders related to hormonal regulation. This review increases awareness of these disparities and encouraged equitable healthcare for those who are disadvantaged.
2022
Chemosphere
A study analyzing 12 commercial bottled water brands found that all tested products contained 2-6 different phthalate chemicals at concentrations ranging from 6.3 to 112.2 ng/mL, with di-n-butyl phthalate (DnBP) showing the highest levels followed by DEHP, DiBP, DMP, DEP, and DiPP. Using an optimized solid-phase microextraction method combined with tandem mass spectrometry, researchers detected these endocrine-disrupting chemicals—which leach from plastic bottles into drinking water—at levels detectable with limits as low as 0.3-2.6 ng/mL. These findings raise significant public health concerns given that phthalates are recognized endocrine disruptors with estrogenic properties that have been linked to breast cancer and other hormone-related health effects, and that billions of people worldwide consume bottled water daily with cumulative lifetime exposures potentially reaching harmful levels, highlighting the urgent need for regulatory limits on phthalates in bottled water and increased adoption of alternative packaging materials that don’t leach endocrine-disrupting chemicals.
2022
Food Chem
A study analyzing 27 vegetable oils using advanced two-dimensional gas chromatography found phthalates—endocrine-disrupting chemicals used as plasticizers that have been linked to cancer—in vegetable oil products, though specific concentration ranges and detection frequencies were not provided in the abstract. The researchers developed a simple, direct analytical method requiring only dilution with solvent (no complex sample preparation) that achieved good repeatability, low detection limits (0.06-2.10 mg/kg), and high accuracy (-9.2% to 10.4%), making it suitable for routine monitoring of phthalate contamination in edible oils. These findings raise concerns about dietary phthalate exposure through cooking oils—a staple food ingredient consumed daily by billions—particularly since phthalates can migrate into oils from plastic packaging, processing equipment, or storage containers, and given their known endocrine-disrupting properties and associations with hormone-related cancers including breast cancer, highlighting the need for stricter regulations on phthalate use in food contact materials and routine monitoring of edible oils for these contaminants.
2022
Crit Rev Food Sci Nutr
This systematic review of 131 epidemiological studies evaluated the association between various endocrine-disrupting chemicals, including phthalates and hormonal exposures like contraceptive pills, and the risk of breast cancer. It found that several EDCs, particularly phthalates and oral contraceptive use, were consistently associated with increased breast cancer risk across multiple studies.
2022
Cancer Epidemiol Biomark Prev
A study of 1,268 women from the Long Island Breast Cancer Study Project with measurements of 22 urinary phthalate and phenol analytes and leukocyte telomere length (LTL)—a biomarker of biological aging—found that LTL significantly modified associations between 11 of 22 analytes and breast cancer risk (p<0.05), with a general pattern showing inverse associations at shorter LTL and positive associations at longer LTL, though no modifying effects were observed for breast cancer mortality. This first study examining biological aging's role in environmental chemical-breast cancer associations reveals complex interactions where the same phthalate/phenol exposures may have opposite effects depending on an individual's telomere length and biological aging status. These findings suggest that biological aging markers like telomere length may help identify women who are more or less susceptible to breast cancer from environmental chemical exposures, highlighting the importance of considering individual variation in biological aging when assessing environmental risk factors and potentially explaining some of the inconsistent associations between phthalates/phenols and breast cancer reported in previous studies that did not account for biological aging heterogeneity.
2022
Sci Rep
A study of drinking water found widespread contamination with phthalates (plastic chemicals) and bisphenol-A, with DEHP—the most common phthalate detected—exceeding safety limits in concentrations up to 8,351 µg/L in winter and 410 µg/L in summer, posing potential health risks to consumers. The research revealed significant seasonal variations with higher contamination in winter than summer, and health risk assessment showed that DEHP exposure from drinking water alone exceeded safe levels (hazard quotient >1), raising concerns about hormone disruption and potential breast cancer risk. These findings highlight an urgent need for water treatment plants to implement better technologies to remove these endocrine-disrupting chemicals and ensure safe drinking water, as current contamination levels may threaten both human and environmental health.
2022
Environ Sci Pollut Res
The following study explores the presence of endocrine disruptors such as phthalates (specifically mono-2-ethyl phthalate and mono-n-butyl phthalate), bisphenol A (BPA), and 1-hydroxypyrene in the urine samples of marginalized Indigenous populations. The study found that 100% of the women sampled showed exposure to these harmful chemicals, with higher concentrations than observed in similar studies from other communities. This increased exposure is linked to environmental and cultural factors, such as the common use of plastic containers and practices such as burning garbage. The women sampled were found to have especially high levels of mono-2-ethyl phthalate, which suggests significant exposure to di(2-ethylhexyl) phthalate. These findings highlight the vulnerability of indigenous communities to pollution due to a lack of awareness, limited healthcare access, and inadequate regulatory measures.
2022
BMJ
Ultra-processed foods (UPFs), commonly found in ready-to-eat items like packaged snacks, frozen meals, and sodas, are filled with added sugars, unhealthy fats, and harmful chemicals like preservatives and flavor enhancers. These foods are increasingly linked to serious health issues, including obesity and cancer. Studies show that replacing UPFs with whole, unprocessed foods can reduce the risk of disease and improve overall health. The harmful ingredients in these products, such as phthalates and bisphenols, can also disrupt the endocrine system, further increasing the risk of developing serious health problems, including cancer.
2022
Biomedicines
This study investigates the effects of di-(2-ethylhexyl) phthalate (DEHP), a common plasticizer, on female rats. It found that exposure to DEHP, even at realistic environmental doses, led to significant disruptions in the rats’ reproductive and thyroid systems. More specifically it found that even low exposure to DEHP over a period of 21 days resulted in a significant decrease in the levels of estrogen and progesterone, which correlated with damage to ovarian follicles. Additionally, the thyroid showed signs of damage, including alterations in hormone regulation. The data in this study suggests that DEHP can potentially lead reproductive issues and impaired ovarian and thyroid gland function.
2022
Biomed Pharmacother
A review of endocrine-disrupting chemicals (EDCs)—ubiquitous substances found in cosmetics, plastic food packaging, and medicines that enter the body through skin, digestive, or respiratory routes—examined their toxic effects even at microgram doses on the female reproductive system and genetic mechanisms. EDCs disrupt endocrine functions by binding to steroid hormone receptors, interfering with hormone synthesis and secretion, and modulating epigenetic processes that can lead to gene expression disturbances, contributing to neoplastic diseases, neurological disorders, circulatory problems, and reproductive dysfunction. Prenatal exposure can affect offspring development, with particular impacts on ovarian function leading to reduced fertility through disturbances in steroid receptor function, steroidogenesis, and gametogenesis. The review emphasizes that despite widespread exposure to these chemicals in everyday products, continued research is needed to fully understand their effects on the female reproductive system and potential transgenerational impacts mediated through epigenetic mechanisms.
2022
Ecotoxicology
An experimental study using wild-type and thyroid hormone receptor alpha knockout (thrαa⁻/⁻) zebrafish embryos/larvae found that avobenzone and octinoxate—organic UV filters commonly used in sunscreens and widely detected in water—disrupt the thyroid endocrine system, with significantly lower survival rates in thrαa⁻/⁻ fish exposed to ≥3 μM of either compound, indicating the thyroid hormone receptor plays a crucial role in their toxicity. Avobenzone exposure increased the T3:T4 ratio with upregulation of the deio2 gene, while both chemicals decreased T4 levels and triggered compensatory upregulation of hypothalamus and pituitary genes (trh, tshβ, tshr), indicating feedback mechanisms attempting to maintain hormonal homeostasis. These findings demonstrate that two widely used sunscreen ingredients act as thyroid endocrine disruptors by affecting thyroid hormone receptors and disrupting the hypothalamus-pituitary-thyroid (HPT) axis, raising concerns about aquatic environmental contamination from these chemicals and potential impacts on thyroid function in exposed organisms, including implications for human exposure through water and dermal application.
2020
Environ Res
A systematic review of 100 publications across 56 epidemiologic studies found that research enriched with women at higher baseline breast cancer risk—through family history, early-onset disease, or genetic susceptibility—consistently showed stronger and more frequent associations between environmental chemical exposures and breast cancer compared to average-risk populations. Specifically, 80% of studies enriched with family history or early-onset cases showed significant associations with exposures including PAHs, air pollution, DDT, PCBs, PFAS, metals, personal care products, and occupational chemicals, while 74% of studies examining genetic susceptibility found significant gene-environment interactions for various pollutants in women with variants affecting carcinogen metabolism, DNA repair, and oxidative stress. These findings suggest that the inconsistent evidence for environmental chemicals and breast cancer in the literature may partly stem from studying predominantly average-risk populations who may be less susceptible to environmental carcinogens, highlighting the critical need for future research to focus on high-risk populations and measure exposures during key windows of susceptibility (puberty, pregnancy, menopause) to more accurately capture the role of environmental chemicals in breast cancer development.
2019
Environ Int
A systematic review of 342 peer-reviewed articles covering 202 unique chemicals used in consumer products analyzed exposure pathways, functional uses, product applications, exposure routes, and associated health risks, finding that phthalates, bisphenol-A, and polybrominated diphenyl ethers were the most frequently studied chemicals, with frequently reported uses including plasticizers, polymers/monomers, and flame retardants in food contact materials, personal care products, cosmetics, furniture, flooring, and electronics. The analysis revealed that publication volume on chemicals tends to surge following major regulatory changes or exposure incidents rather than before market introduction, indicating a reactive rather than proactive approach to chemical safety assessment. These findings highlight the critical gap between the increasingly diverse array of chemicals used in consumer products and our lagging understanding of their exposure pathways and human health risks, emphasizing the urgent need to develop capacity and mechanisms for identifying health risks prior to chemical releases rather than after exposure incidents or regulatory action, to enable preventive rather than reactive public health protection.
2019
Environ Res
This study investigated how DEHP (a common plastic additive) and its metabolite MEHP affect breast cancer-related markers in T-47D breast cancer cells exposed to various concentrations for 4 days. The researchers found that high-dose DEHP (10,000 nM) and low-dose MEHP (0.1 nM) significantly increased cell proliferation without causing cell death, and DEHP also increased progesterone receptor (PR) protein levels and nuclear accumulation. When cells were treated with a progesterone receptor blocker (Mifepristone), the increased cell growth was completely prevented and PR nuclear levels were partially reduced, indicating that DEHP promotes breast cancer cell proliferation through progesterone receptor activation. The findings suggest that DEHP exposure may increase breast cancer risk by activating progesterone signaling pathways, though the exact mechanisms and long-term consequences require further investigation.
2019
Environ Pollut
This study investigated how three endocrine-disrupting chemicals (BPA, BBP, and DEHP) affect estrogen receptor alpha (ERα) activity under normal and low-oxygen (hypoxic) conditions in breast and endometrial cancer cells. The researchers found that BPA and BBP activated ERα at specific concentrations, while DEHP did not, but all three chemicals enhanced ERα-mediated gene activity and decreased ERα protein levels under hypoxic conditions. BPA and BBP also affected hypoxia-related factors, decreasing hypoxia-inducible factor-1 activity while increasing VEGF (a blood vessel growth factor) secretion in breast cancer cells, whereas DEHP had different effects. The findings suggest that these endocrine disruptors can alter ERα regulation under low-oxygen conditions, which may influence disease processes since hypoxia is common in tumors and other pathological states.
2018
PLOS One
This study investigated how phthalates affect the growth of normal breast cells (MCF-10A) when grown alongside breast fibroblasts derived from tissue near estrogen receptor (ER) positive and negative breast cancers. The researchers found that only fibroblasts from ER-positive breast cancer tissue significantly stimulated breast cell proliferation, and when these co-cultures were exposed to estrogen or three phthalates (BBP, DBP, DEHP), cell growth increased significantly along with markers of cell division and estrogen receptor expression. The effects of phthalates on normal breast cells were similar to those of estrogen and depended on estrogen receptor activity, suggesting that phthalates act through hormone-mediated pathways. The study concludes that phthalates should be considered potential endocrine disruptors with breast cancer risk implications, even at low concentrations, particularly in the presence of estrogen-responsive tissue.
2018
Food Chem Tox
A systematic review of 25 studies examining phthalates (plastic chemicals) and breast cancer found that while laboratory studies show certain phthalates can activate estrogen receptors and promote cancer cell growth, epidemiological studies in humans have produced mixed and inconclusive results. The main source of phthalate exposure is through diet—particularly from food and beverages in plastic packaging—but current human studies have significant limitations in how they measure exposure and account for other risk factors. The review calls for better-designed future studies that use hair samples instead of urine for more accurate long-term exposure assessment, include dietary factors and genetic markers as confounders, and investigate phthalates’ effects beyond just estrogen-driven cancers to include all breast cancer subtypes.
2018
Oncol Rep
This study investigated whether exposure to bisphenol A (BPA) and phthalate metabolites affects breast cancer risk through epigenetic changes in the ADAM33 gene, which plays a role in cancer progression. The researchers conducted a case-control study with 44 breast cancer patients and 22 controls, analyzing ADAM33 gene methylation patterns in blood samples and measuring urinary concentrations of endocrine-disrupting chemicals. They found that certain phthalate metabolites (MEHHP, MECPP, MEOHP) were positively associated with increased methylation of the ADAM33 gene, which was linked to higher gene expression levels. Surprisingly, the study suggests these phthalate metabolites may have a protective effect against breast cancer by increasing ADAM33 methylation and expression, contrary to the typical expectation that endocrine disruptors increase cancer risk.
2018
Tox Lett
This study investigated how butyl benzyl phthalate (BBP), a common environmental contaminant linked to breast cancer, promotes cancer cell growth and identified the molecular mechanisms involved. The researchers found that BBP increased proliferation in both estrogen receptor-positive (MCF-7) and negative (MDA-MB-231) breast cancer cells by promoting cell cycle progression and upregulating growth-promoting proteins while downregulating tumor suppressor proteins. For the first time, the study revealed that BBP works through modulating microRNA-19a/b, which targets the tumor suppressor gene PTEN, leading to activation of the AKT signaling pathway that promotes cell growth. These findings provide new insights into how BBP contributes to breast cancer development at the molecular level and suggest potential targets for intervention.
2017
Molec Cell Endocrinol
This study examines the role of environmental estrogen-like endocrine-disrupting chemicals (EEDs) in breast cancer development. EEDs are synthetic compounds that mimic estrogen, and the ones being studied in this paper include polychlorinated biphenyls (PCBs), bisphenol A (BPA), and phthalates. The results of the study show that of the EEDs tested, only one type of PCB, PCB138, had a strong association with the formation of breast cancer, where as phthalates (and it metabolites) but and BPA showed no strong correlation. Additionaly, the researchers identify that these EEDs promote the proliferation of breast cancer cells, induce epigenetic changes that may increase susceptibility to cancer, as well as alter developmental pathways during critical windows of breast development.
2015
Carcinogenesis
A review examining the intersection of environmental toxicants, immune function, and cancer development argues that common chemicals like bisphenol A, atrazine, and phthalates can disrupt the delicate balance between pro- and anti-inflammatory immune responses, potentially contributing to tumor development through immune system dysfunction. The authors highlight that while the role of immunity in cancer is well-established, research on how environmental chemicals affect immune cells as co-factors in cancer causation remains underdeveloped compared to studies on autoimmunity and allergies. The review calls for increased research using systems biology approaches to better understand how chemical exposures disturb inflammatory pathways and immune molecules involved in tumor-associated inflammation, arguing that chemically induced immune perturbations represent an important but understudied mechanism of environmental carcinogenesis.
2015
Carcinogenesis
This study explores the linkage between environmental chemical exposures and cellular resistance to cell death, a carcinogenic trait. The researchers in this study specifically investigate BPA, chlorothalonil, dibutyl phthalate, and more because of their disruptive effects that may be involved in these carcinogenic pathways. The researchers found that arsenic interferes with cellular signaling pathways and induces oxidative stress, leading to impaired apoptosis; dioxins bind to aryl hydrocarbon receptors (AHRs), which alters gene expression and disrupts normal cell death processes; BPA mimics the estrogen hormone, affecting hormonal balance and promoting cell survival pathways that inhibit cell death. By allowing cells to evade cell death, these environmental chemicals can promote the survival of cells with genetic mutations and therefore increase the risk of cancer development.
2014
Aging Dis
The following review article described how exposure to EDCs during early development can lead to adverse health outcomes later in life through epigenetic mechanisms based on existing studies. The article emphasizes that exposure to EDCs during critical developmental periods such as in utero and early childhood, can have lasting effects on health since, during these periods, the body’s systems are particularly vulnerable to exposures. Additionally, the article finds a link between early-life exposure to EDCs and increased risk of various health issues later on in life, including metabolic disorders and cancers. The suspected mechanism by which these chemicals do this is thought to be mediated by epigenetic changes, which are changes to gene expression without altering the DNA. Therefore, the article emphasizes understanding how exposure during such sensitive periods in development can pose such drastic problems later on in life.