Endocrine Disruptors and Polycystic Ovary Syndrome: Phthalates

Research mechanism of DBP and DEHP in the development of PCOS based on network toxicology and molecular docking

Polycystic ovary syndrome (PCOS) constitutes a prevalent endocrine disorder among females, exhibiting a significant incidence rate. The etiology of PCOS predominantly attributes to environmental determinants. Phthalate esters, including dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP), have been demonstrated to exert detrimental effects on reproductive function. However, the effects of these plasticizers on female reproductive health have not been clearly investigated. In the present investigation, we employed network toxicological methodologies to delineate the pivotal genes and associated pathways that are implicated in the pathogenesis of PCOS induced by DBP and DEHP. Molecular docking methodologies were employed to ascertain the interaction between the investigational compound and the designated target protein. The present study delineates pivotal targets, namely AKT1, SRC, PIK3R1, EGFR, ESR1, and STAT3, which are instrumental in the mediation of PCOS. The genes predominantly participate in the EGFR pathway, insulin signaling pathway, and oocyte damage, significantly compromising female ovarian functionality. This investigation underscores the integration of network toxicology, molecular docking, and cell experiment methodologies to elucidate the toxicological properties and underlying molecular mechanisms of plasticizers in the context of PCOS. This study provides a prospective therapeutic target to mitigate the harmful effects of plasticizers on female reproductive health.

Environmental exposure to selected non-persistent endocrine disrupting chemicals and polycystic ovary syndrome: a systematic review

Polycystic ovary syndrome (PCOS) is an endocrine disorder manifesting with symptoms such as irregular menstrual cycles, hyperandrogenism, and/or polycystic ovaries. The exact cause of PCOS remains unknown, but it is believed to result from a combination of genetic predisposition, insulin resistance, low-grade inflammation, and excessive androgen production. Various environmental factors, especially endocrine-disrupting chemicals (EDCs), in addition to genetic and hormonal ones, also may influence PCOS. This is one of the first systematic reviews dealing with the exposure to non-persistent endocrine disrupting chemicals and PCOS. The review summarizes the existing knowledge about the association of EDCs with PCOS based on significant findings on the toxicity of various non-persistent environmental EDCs and polycyclic ovarian syndrome risk. A systematic search of the literature was conducted in order to identify proper studies using PubMed, Scopus, Elsevier, and Springer databases. The results of the studies suggest that there is a positive association between bisphenol A (BPA), phthalates, octocrylene, and PCOS. The data concerning triclosan and PCOS were inconclusive. Additionally, no link between the exposures to parabens and PCOS was observed. These results of the presented studies highlight the urgent need for continued research on EDCs and their role in PCOS. Int J Occup Med Environ Health. 2025;38(2):98-121.

Associations between urinary and follicular fluid concentrations of phthalate metabolites and reproductive outcomes in Brazilian women undergoing fertility treatment

Existing literature indicates that phthalates can be toxic to the ovaries, negatively affecting female reproduction and potentially influencing outcomes in assisted reproductive technology (ART). However, data on associations between urinary and/or follicular fluid phthalate concentrations and ART outcomes in South American women are scarce. Therefore, in this prospective study, we recruited 93 women (n = 119 cycles) undergoing ART at a fertility clinic in Brazil. They provided urine and follicular fluid (FF) samples, from which we measured the concentrations of the 15 phthalate metabolites more frequently found in Brazilian populations. We documented both laboratorial and clinical outcomes, estimating associations using negative binomial regression. Our findings revealed that specific oocyte and embryo development parameters were associated with urinary concentrations of phthalate metabolite. Particularly, number of follicles, maturation, as well as blastulation were negatively associated with Mono-benzyl phthalate (MBzP). Similarly, urinary mono-ethyl phthalate (MEP) was associated with lower rates of maturation, good quality and blastulation. However, some parameters positively associated with mono-(carboxyisooctyl) phthalate (MCiOP), including maturation, good quality, and blastulation. We also observed certain associations between embryo development and FF concentrations of phthalate metabolite, although the magnitude and direction of these associations differed among various metabolites. Overall, our results suggest that urinary and FF concentrations of phthalate metabolite may be linked to altered outcomes in ART cycles. However, further studies are needed to clarify the extent of this impact. Our results support previous literature and is the first to evaluate urinary and FF phthalate metabolites concentrations in South American women undergoing infertility treatment.

The association between polycystic ovary syndrome and environmental pollutants based on animal and human study; a systematic review

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders. This abnormality is identified with hyperandrogenism, polycystic ovary and ovulation disorder. Environmental factors are one of the etiologies of this disease. In this systematic review, a search was performed with the keywords of polycystic ovary syndrome, PCOS, pesticides, organochlorine, heavy metals, PCBs, PAHs, bisphenol A, BPA, phthalates, mycotoxin, Tributyltin, TBT, environmental contaminants, regardless of publication time. 567 studies were obtained and after assessing 26 articles were finally selected. 61 % of the studies were attributed to bisphenol A. The positive correlation was seen between bisphenol A, tributyltin, air pollutants and organic contaminates with this disease. The association between this syndrome and bisphenol A in adolescents was also confirmed. Zinc has led to a reduction in the incidence of disease in almost all research literature. This issue can be considered in the prevention of the disease.

Environmental Exposures and Polycystic Ovary Syndrome: A Review

Polycystic ovary syndrome (PCOS) is the most common heterogeneous endocrine disorder in women of reproductive age, affecting around 5 to 10% of women and up to 21% depending on the applied diagnostic criteria and study population. People with PCOS may experience oligomenorrhea, androgen excess, and polycystic ovary morphology. The etiology of the disease is not completely understood, with genetics, epigenetics, endocrine, metabolic, lifestyle, and environmental factors contributing to its development and severity. Environmental exposures are an important, burgeoning field in menstrual research, as they potentially link to menstrual cycle disruption and the risk of reproductive disorders such as PCOS. This review examines the recent research investigating environmental exposures-air pollution, micro- and nanoplastics, heavy metals, and endocrine-disrupting chemicals-and PCOS in human and animal models, concluding with potential mechanisms, limitations, and considerations for future work. Overall, research on environmental exposures and PCOS is limited and yields heterogeneous results across studies. Specifically, exposures such as air pollutants, micro- and nanoplastics, persistent organic pollutants, and parabens have noticeably limited research. Future research can help fill the gap in understanding how environmental exposures, particularly across gestational, childhood, and reproductive adult life stages, may impact PCOS.

Endocrine-Disrupting Chemicals, Hypothalamic Inflammation and Reproductive Outcomes: A Review of the Literature

Endocrine-disrupting chemicals (EDCs) are environmental and industrial agents that interfere with hormonal functions. EDC exposure is linked to various endocrine diseases, especially in reproduction, although the mechanisms remain unclear and effects vary among individuals. Neuroinflammation, particularly hypothalamic inflammation, is an emerging research area with implications for endocrine-related diseases like obesity. The hypothalamus plays a crucial role in regulating reproduction, and its inflammation can adversely affect reproductive health. EDCs can cross the blood-brain barrier, potentially causing hypothalamic inflammation and disrupting the reproductive axis. This review examines the existing literature on EDC-mediated hypothalamic inflammation. Our findings suggest that exposure to 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD), polychlorinated biphenyl (PCB), tributyltin (TBT), phthalates, bisphenol A (BPA), and chlorpyrifos (CPF) in animals is linked to hypothalamic inflammation, specifically affecting the hypothalamic centers of the gonadotropic axis. To our knowledge, this is the first comprehensive review on this topic, indicating hypothalamic inflammation as a possible mediator between EDC exposure and reproductive dysfunction. Further human studies are needed to develop effective prevention and treatment strategies against EDC exposure.

Endocrine-disrupting chemicals and hormonal profiles in PCOS women: A comparative study between urban and rural environment

Polycystic Ovary Syndrome (PCOS), a multifaceted endocrine disorder, affects a significant proportion of women globally, with its etiology rooted in both genetic and environmental factors. This study delves into the environmental aspect, particularly focusing on the role of endocrine-disrupting chemicals (EDCs) in the context of urbanization and industrialization. This research examines the impact of endocrine-disrupting chemicals (EDCs) - Bisphenol A (BPA), Mono-ethyl Hexyl Phthalate (MEHP), and Di-ethyl Hexyl Phthalate (DEHP) - on 40 women with Polycystic Ovary Syndrome (PCOS) across urban and rural Gujarat. Employing High-Performance Liquid Chromatography (HPLC) and chemiluminescence, we analyzed their blood samples for EDCs levels and hormonal parameters. Urban individuals displayed significantly higher BPA and DEHP concentrations, highlighting the environmental exposure differences. Notably, urban exposure to MEHP and DEHP correlated with a marked decrease in estradiol levels, while rural DEHP exposure was associated with an increase in estradiol but a decrease in prolactin and DHEAS levels. These findings illuminate the variable effects of EDC exposure on hormonal profiles in PCOS, influenced by geographical and environmental contexts. The study underscores the critical need for tailored environmental health policies to mitigate the diverse impacts of EDCs, advocating for a nuanced approach to PCOS management that considers environmental exposures. Our insights contribute to the understanding of PCOS's hormonal dynamics, emphasizing the significance of addressing EDC exposure in different settings.

Advances in understanding the reproductive toxicity of endocrine-disrupting chemicals in women

Recently, there has been a noticeable increase in disorders of the female reproductive system, accompanied by a rise in adverse pregnancy outcomes. This trend is increasingly being linked to environmental pollution, particularly through the lens of Endocrine Disrupting Chemicals (EDCs). These external agents disrupt natural processes of hormones, including synthesis, metabolism, secretion, transport, binding, as well as elimination. These disruptions can significantly impair human reproductive functions. A wealth of animal studies and epidemiological research indicates that exposure to toxic environmental factors can interfere with the endocrine system's normal functioning, resulting in negative reproductive outcomes. However, the mechanisms of these adverse effects are largely unknown. This work reviews the reproductive toxicity of five major environmental EDCs-Bisphenol A (BPA), Phthalates (PAEs), Triclocarban Triclosan and Disinfection Byproducts (DBPs)-to lay a foundational theoretical basis for further toxicological study of EDCs. Additionally, it aims to spark advancements in the prevention and treatment of female reproductive toxicity caused by these chemicals.

The adverse role of endocrine disrupting chemicals in the reproductive system

Reproductive system diseases pose prominent threats to human physical and mental well-being. Besides being influenced by genetic material regulation and changes in lifestyle, the occurrence of these diseases is closely connected to exposure to harmful substances in the environment. Endocrine disrupting chemicals (EDCs), characterized by hormone-like effects, have a wide range of influences on the reproductive system. EDCs are ubiquitous in the natural environment and are present in a wide range of industrial and everyday products. Currently, thousands of chemicals have been reported to exhibit endocrine effects, and this number is likely to increase as the testing for potential EDCs has not been consistently required, and obtaining data has been limited, partly due to the long latency of many diseases. The ability to avoid exposure to EDCs, especially those of artificially synthesized origin, is increasingly challenging. While EDCs can be divided into persistent and non-persistent depending on their degree of degradation, due to the recent uptick in research studies in this area, we have chosen to focus on the research pertaining to the detrimental effects on reproductive health of exposure to several EDCs that are widely encountered in daily life over the past six years, specifically bisphenol A (BPA), phthalates (PAEs), polychlorinated biphenyls (PCBs), parabens, pesticides, heavy metals, and so on. By focusing on the impact of EDCs on the hypothalamic-pituitary-gonadal (HPG) axis, which leads to the occurrence and development of reproductive system diseases, this review aims to provide new insights into the molecular mechanisms of EDCs' damage to human health and to encourage further in-depth research to clarify the potentially harmful effects of EDC exposure through various other mechanisms. Ultimately, it offers a scientific basis to enhance EDCs risk management, an endeavor of significant scientific and societal importance for safeguarding reproductive health.

Plastic use for food and drinks and related knowledge, attitudes, and practices among a sample of Egyptians

Introduction

Plastic is extensively used in everyday life, particularly for food and beverage containers. The inappropriate use of these containers may lead to the leaching of various chemicals from plastic, such as bisphenol A, phthalate, and styrene, which cause numerous adverse health effects. This study aimed to assess the knowledge, attitudes, and practices toward using plastic for food and drinks among a sample of the Egyptian population.

Materials and methods

A questionnaire was designed based on scientific literature to assess sociodemographic data, knowledge, attitudes, and practices toward the use of plastic for food and drinks. A total of 639 participants were recruited by employing the convenience sampling technique.

Results

More than half of the participants (347, 54%) had poor knowledge scores. Personal experiences, social media, and web pages represented the most common knowledge sources. A comparison between plastic-related knowledge scores and the studied sociodemographic characteristics revealed statistically significant differences in age, gender, education, marital status, residence, working, and socioeconomic standard. A good attitude was reported by the majority (515, 80.6%) of participants. The majority (493, 77.2%) were occasional and frequent plastic users and the practice scores were significantly associated with age, education, residence, and socioeconomic standard. Higher educational level, gender (women), and rural residence were predictors of good participants knowledge, while lower socioeconomic status and urban residence were predictors of bad participants practice in a multivariate logistic regression analysis.

Conclusion

The observed unsatisfactory knowledge and practice scores vs. the high attitude indicates a knowledge gap that can help direct future improvements. We call for public awareness programs about safe plastic use and the related health hazards of plastic chemicals. We also stress upon the urgent need for a collaboration between health authorities and the plastic and food industry to guarantee that information about proper plastic use is conveyed to consumers.

Individual and joint associations of urinary phthalate metabolites with polycystic ovary and polycystic ovary syndrome: Results from the TREE cohort

Phthalates are widespread endocrine disrupting chemicals that adversely affect female reproductive health. We aimed to investigate the individual and joint associations of phthalate exposures measured by repeated urinary metabolites with polycystic ovary (PCO) and polycystic ovary syndrome (PCOS) (96 PCO cases, 96 PCOS cases and 370 controls). In single-pollutant analyses, mono-isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP) and the sum of di(2-ethylhexyl) phthalate (∑DEHP) were associated with increased prevalence of PCO. Mono(2-ethylhexyl) phthalate (MEHP), MBzP and ∑DEHP were associated with elevated prevalence of PCOS. In multiple-pollutant analyses, one-quartile increase of weighted quantile sum index in phthalate metabolite mixtures was associated with increased prevalence of PCO and PCOS, and MBzP was the most major contributor. Our findings suggest a potential role for phthalate exposures, both individually and in mixtures, in the development of PCO and PCOS.

The effects of phthalate exposure on metabolic parameters in polycystic ovary syndrome

BACKGROUND-AIM

Phthalates are known as endocrine disrupting chemicals which are present in wide-range of products. The objective of the study was to investigate whether phthalate exposure may attribute to the metabolic syndrome development in women with polycystic ovary syndrome (PCOS).

METHOD

The cross-sectional study involved 60 women in reproductive age with confirmed PCOS. Anthropometric and biochemical measurements were examined together with detected levels of ten phthalate metabolites measured by GC-MS in morning urine samples.

RESULTS

In this study at least one phthalate metabolite was detected in 51.7% of samples. Total phthalate metabolites urine concentrations were positively associated with BMI, waist circumference, waist-to-height-ratio (WtHR), leptin serum levels as well as lipid accumulation product (LAP) and visceral adiposity index (VAI). Mono-methyl-phthalate (MMP) levels was significantly correlated with WtHR, LAP and VAI. Additionally, total phthalate metabolites levels were significantly linked with fasting plasma glucose and HOMA index, whereas MMP concentrations were associated with fasting plasma glucose and insulin levels. Total cholesterol (TC) level was statistically significantly higher among PCOS women with detected phthalate metabolites compared to those without phthalates. The sum of all phthalates was correlated with LDL and triglyceride levels as well as TC/HDL. MMP concentrations were linked positively with TC, LDL and triglyceride levels as well as with TC/HDL. It is noteworthy that MMP concentrations were positively associated with testosterone serum levels while the total phthalate metabolites concentrations were also linked but with moderate significance.

CONCLUSIONS

The increased phthalate metabolites concentrations may interfere with obesity, glucose and lipid impairment in PCOS women. Additionally, testosterone serum levels can be disrupted by MMP.

Endocrine disruptor chemicals, adipokines and reproductive functions

The prevalence of adult obesity has risen markedly in recent decades. The endocrine system precisely regulates energy balance, fat abundance and fat deposition. Interestingly, white adipose tissue is an endocrine gland producing adipokines, which regulate whole-body physiology, including energy balance and reproduction. Endocrine disruptor chemicals (EDCs) include natural substances or chemicals that affect the endocrine system by multiple mechanisms and increase the risk of adverse health outcomes. Numerous studies have associated exposure to EDCs with obesity, classifying them as obesogens by their ability to activate different mechanisms, including the differentiation of adipocytes, increasing the storage of triglycerides, or elevating the number of adipocytes. Moreover, in recent years, not only industrial deception and obesity have intensified but also the problem of human infertility. Reproductive functions depend on hormone interactions, the balance of which may be disrupted by various EDCs or obesity. This review gives a brief summary of common EDCs linked with obesity, the mechanisms of their action, and the effect on adipokine levels, reproduction and connected disorders, such as polycystic ovarian syndrome, decrease in sperm motility, preeclampsia, intrauterine growth restriction in females and decrease of sperm motility in males.

The relationship between urinary phthalate metabolites and polycystic ovary syndrome in women undergoing in vitro fertilization: Nested case-control study

Certain endocrine disruptor chemicals are involved in the pathogenesis of polycystic ovary syndrome (PCOS), a hormonal disease related to infertility in women. Phthalates are the most common plasticizers found in several consumer products. Experimental and epidemiologic evidence suggests that some phthalates disrupt endocrine functions in reproductive mechanisms and development. We previously measured the levels of eight phthalate metabolites in the urine of 599 Saudi women who underwent in vitro fertilization (IVF) treatment and were enrolled in a prospective study (2015-2017). The current nested case-control study aimed to determine the association between urinary levels of phthalate metabolites and PCOS. Overall, 441 women from the IVF study were identified as eligible for this study. Women in the case group included those diagnosed with PCOS (N = 82). The control group comprised those unable to conceive due to male azoospermia or who underwent preimplantation genetic diagnosis (N = 359). Most urinary phthalate metabolite levels were several-fold higher than those reported in national surveys from other countries. The ratio of luteinizing hormone to follicle-stimulating hormone, an index of PCOS, was significantly higher in the case than in the control group, with no indication of its association with phthalate metabolites. The logistic regression model was applied after adjusting for confounders to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for each metabolite modeled as a natural logarithm (ln). For each ln-unit increase in the sum of the four di (2-ethylhexyl) phthalate (∑₄DEHP) metabolites as well as two individual metabolites, mono-(2-ethyl-5-oxohexyl) phthalate and mono-(2-ethyl-5-carboxypentyl) phthalate, the odds of PCOS increased by 40.5% [OR = 1.405 (95% CI: 1.025, 1.925)], 41.1% [OR = 1.055 (95% CI: 1.055, 1.885)], and 38.6% [OR = 1.386 (95% CI: 1.033, 1.86)], respectively. In contrast, the % odds of PCOS decreased marginally significantly by 44% [OR = 0.560 (95% CI: 0.313, 1.002)] with an ln-unit increase of %MEHP₄, the ratio of mono-(2-ethylhexyl) phthalate to ∑₄DEHP. These findings suggest that DEHP may contribute to PCOS, and further investigation is required to understand the underlying mechanisms.

Endocrine disruptors, obesity, and cytokines - how relevant are they to PCOS?

As environmental and genetic components contribute to the PCOS expression, we compared levels of endocrine disruptors, steroid hormones, cytokines, and metabolic parameters in twenty healthy, nine normal-weight PCOS women, and ten obese PCOS women. Steroid hormones, bisphenols (BPA, BPS, BPF, BPAF) and parabens (methyl-, ethyl-, propyl-, butyl-, benzyl-parabens) were measured by liquid chromatography-tandem mass spectrometry. Differences between the groups were assessed using the Mann-Whitney U test. Spearman correlation coefficients were calculated for the individual parameters relationship. Significantly higher levels of BPA, anti-Müllerain hormone, lutropine, lutropine/folitropine ratio, testosterone, androstenedione, 7beta-OH-epiandrosterone, and cytokines (IL-6, VEGF, PDGF-bb), were found in normal-weight PCOS women compared to controls. Between normal-weight and obese PCOS women, there were no differences in hormonal, but in metabolic parameters. Obese PCOS women had significantly higher insulin resistance, fatty-liver index, triglycerides, cytokines (IL-2, IL-13, IFN-gamma). In healthy, but not in PCOS, women, there was a positive correlation of BPA with testosterone, SHBG with lutropine, and folitropine, while testosterone negatively correlated with SHBG. In obese women with PCOS, insulin resistance negatively correlated with SHBG and estradiol. No differences were observed in the paraben exposure. Levels of BPA were higher in PCOS women, indicating its role in the etiology. Obesity significantly worsens the symptoms.

Endocrine disrupting chemicals and reproductive disorders in women, men, and animal models

This chapter covers the known effects of endocrine disrupting chemicals (EDCs) on reproductive disorders. The EDCs represented are highly studied, including plasticizers (bisphenols and phthalates), chemicals in personal care products (parabens), persistent environmental contaminants (polychlorinated biphenyls), and chemicals in pesticides or herbicides. Both female and male reproductive disorders are reviewed in the chapter. Female disorders include infertility/subfertility, irregular reproductive cycles, early menopause, premature ovarian insufficiency, polycystic ovarian syndrome, endometriosis, and uterine fibroids. Male disorders include infertility/subfertility, cryptorchidism, and hypospadias. Findings from both human and animal studies are represented.