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Dermitzakis I, Theotokis P, Axarloglou E, Delilampou E, Manthou ME, Meditskou S. Effects of hazardous chemicals on secondary sex ratio: A comprehensive review. CHEMOSPHERE 2024; 361:142467. [PMID: 38810798 DOI: 10.1016/j.chemosphere.2024.142467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 04/15/2024] [Accepted: 05/26/2024] [Indexed: 05/31/2024]
Abstract
The secondary sex ratio (SSR), defined as the ratio of male to female offspring at birth, has garnered significant scientific interest due to its potential impact on population dynamics and evolution. In recent years, there has been a growing concern regarding the potential consequences of environmental chemicals on the SSR, given their widespread exposure and potential enduring ramifications on the reproductive system. While SSR serves as an indicator of health, ongoing research and scientific inquiry are being conducted to explore the potential relationship between chemicals and offspring ratio. Although some studies have suggested a possible correlation, others have yielded inconclusive results, indicating that the topic is intricate and still needs to be elucidated. The precise mechanism by which chemical agents exert their influence on the SSR remains ambiguous, with disruption of the endocrine system being a prominent justification. In light of the complex interplay between chemical exposure and SSR, the present review aims to comprehensively examine and synthesize existing scientific literature to gain a deeper understanding of how specific chemical exposures may impact SSR. Insights into chemical hazards that shift SSR patterns or trends could guide prevention strategies, including legislative bans of certain chemicals, to minimize environmental and public health risks.
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Affiliation(s)
- Iasonas Dermitzakis
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Paschalis Theotokis
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Evangelos Axarloglou
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Efthymia Delilampou
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Maria Eleni Manthou
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Soultana Meditskou
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece.
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Wu C, Du X, Liu H, Chen X, Ge K, Meng R, Zhang Z, Zhang H. Advances in polychlorinated biphenyls-induced female reproductive toxicity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170543. [PMID: 38309369 DOI: 10.1016/j.scitotenv.2024.170543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/26/2024] [Accepted: 01/27/2024] [Indexed: 02/05/2024]
Abstract
Polychlorinated biphenyls (PCBs) are a class of endocrine-disrupting chemicals (EDCs) widely present in the environment. PCBs have been of concern due to their anti/estrogen-like effects, which make them more toxic to the female reproductive system. However, there is still a lack of systematic reviews on the reproductive toxicity of PCBs in females, so the adverse effects and mechanisms of PCBs on the female reproductive system were summarized in this paper. Our findings showed that PCBs are positively associated with lower pregnancy rate, hormone disruption, miscarriage and various reproductive diseases in women. In animal experiments, PCBs can damage the structure and function of the ovaries, uterus and oviducts. Also, PCBs could produce epigenetic effects and be transferred to the offspring through the maternal placenta, causing development retardation, malformation and death of embryos, and damage to organs of multiple generations. Furthermore, the mechanisms of PCBs-induced female reproductive toxicity mainly include receptor-mediated hormone disorders, oxidative stress, apoptosis, autophagy, and epigenetic modifications. Finally, we also present some directions for future research on the reproductive toxicity of PCBs. This detailed information provided a valuable reference for fully understanding the reproductive toxicity of PCBs.
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Affiliation(s)
- Chunrui Wu
- College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Xingde Du
- College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Haohao Liu
- College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Xinghai Chen
- Department of Chemistry and Biochemistry, St Mary's University, San Antonio, TX, USA
| | - Kangfeng Ge
- College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Ruiyang Meng
- College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Zongxin Zhang
- College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Huizhen Zhang
- College of Public Health, Zhengzhou University, Zhengzhou 450001, Henan, China.
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Barat S, Hood RB, Terrell ML, Howards PP, Spencer JB, Wainstock T, Barton H, Pearson M, Kesner JS, Meadows JW, Marcus M, Gaskins AJ. In-utero exposure to polybrominated biphenyl (PBB) and menstrual cycle function in adulthood. Int J Hyg Environ Health 2024; 256:114297. [PMID: 38039561 PMCID: PMC10872753 DOI: 10.1016/j.ijheh.2023.114297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 10/12/2023] [Accepted: 11/23/2023] [Indexed: 12/03/2023]
Abstract
BACKGROUND There is evidence that in-utero exposure to PBBs, and similar chemicals, are associated with several adverse reproductive health outcomes including altered pubertal timing. However, less is known about the effects of in-utero exposure to PBBs on menstrual cycle function and reproductive hormone levels in adulthood. METHODS For this menstrual cycle study, we recruited reproductive-aged women in the Michigan PBB Registry who were not pregnant, lactating, or taking hormonal medications (2004-2014). A total of 41 women who were born after the PBB contamination incident (1973-1974) and were prenatally exposed to PBBs, were included in this analysis. We estimated in-utero PBB exposure using maternal serum PBB measurements taken after exposure and extrapolated to time of pregnancy using a PBB elimination model. Women were followed for up to 6 months during which they provided daily urine samples and completed daily diaries. The urine samples were assayed for estrone 3-glucuronide (E13G), pregnanediol 3-glucuronide (Pd3G), and follicle stimulating hormone (FSH). RESULTS Women in our study were, on average, 27.5 (SD:5.3) years old and contributed 4.9 (SD:1.9) menstrual cycles of follow-up. Compared to women with low in-utero PBB exposure (≤1 ppb), women with medium (>1.0-3.0 ppb) and high (>3.0 ppb) exposure had higher maximum 3-day mean Pd3G levels during the luteal phase. Specifically, the age- and creatinine-adjusted maximum 3-day mean luteal phase Pd3G levels (95% CI) in increasing categories of in-utero PBB exposure were 9.2 (4.6,13.9), 14.8 (11.6,18.0), and 16.1 (12.9,19.3) μg/mg creatinine. There were no meaningful differences in average cycle length, follicular or luteal phase cycle length, bleed length, or creatinine-adjusted E13G or FSH levels by category of in-utero PBB exposure. CONCLUSION Higher exposure to PBB in-utero was associated with increased progesterone levels across the luteal phase, however, most other menstrual cycle characteristics were largely unassociated with in-utero PBB exposure. Given our modest sample size, our results require cautious interpretation.
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Affiliation(s)
- Suman Barat
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Robert B Hood
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Metrecia L Terrell
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Penelope P Howards
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jessica B Spencer
- Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Emory University School of Medicine, Atlanta, GA, USA
| | - Tamar Wainstock
- Department of Public Health, Faculty of Health Sciences, Ben-Gurion University, Be'er Sheva, Israel
| | - Hillary Barton
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Melanie Pearson
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - James S Kesner
- Division of Applied Research and Technology, National Institute for Occupational Safety & Health, Cincinnati, OH, USA
| | - Juliana W Meadows
- Health Effects Laboratory Division, National Institute for Occupational Safety & Health, Cincinnati, OH, USA
| | - Michele Marcus
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA; Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Audrey J Gaskins
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
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Hassan S, Thacharodi A, Priya A, Meenatchi R, Hegde TA, R T, Nguyen HT, Pugazhendhi A. Endocrine disruptors: Unravelling the link between chemical exposure and Women's reproductive health. ENVIRONMENTAL RESEARCH 2024; 241:117385. [PMID: 37838203 DOI: 10.1016/j.envres.2023.117385] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/29/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023]
Abstract
An Endocrine Disrupting Chemical (EDC) is any compound that disrupts the function of the endocrine system in humans and is ubiquitous in the environment either as a result of natural events or through anthropogenic activities. Bisphenol A, phthalates, parabens, pesticides, triclosan, polychlorinated biphenyls, and heavy metals, which are frequently found in the pharmaceutical, cosmetic, and packaging sectors, are some of the major sources of EDC pollutants. EDCs have been identified to have a deteriorating effect on the female reproductive system, as evidenced by the increasing number of reproductive disorders such as endometriosis, uterine fibroids, polycystic ovary syndrome, premature ovarian failure, menstrual irregularity, menarche, and infertility. Studying EDCs in relation to women's health is essential for understanding the complex interactions between environmental factors and health outcomes. It enables the development of strategies to mitigate risks, protect reproductive and overall health, and inform public policy decisions to safeguard women's well-being. Healthcare professionals must know the possible dangers of EDC exposure and ask about environmental exposures while evaluating patients. This may result in more precise diagnosis and personalized treatment regimens. This review summarises the existing understanding of prevalent EDCs that impact women's health and involvement in female reproductive dysfunction and underscores the need for more research. Further insights on potential mechanisms of action of EDCs on female has been emphasized in the article. We also discuss the role of nutritional intervention in reducing the effect of EDCs on women's reproductive health. EDC pollution can be further reduced by adhering to strict regulations prohibiting the release of estrogenic substances into the environment.
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Affiliation(s)
- Saqib Hassan
- Department of Biotechnology, School of Bio and Chemical Engineering, Sathyabama Institute of Science and Technology, Chennai, Tamilnadu, 600119, India; Future Leaders Mentoring Fellow, American Society for Microbiology, Washington, 20036, USA
| | - Aswin Thacharodi
- Dr. Thacharodi's Laboratories, Department of Research and Development, Puducherry, 605005, India
| | - Anshu Priya
- SRF-ICMR, CSIR-Institute of Genomics and Integrative Biology (IGIB), South Campus, New Delhi, 110025, India
| | - R Meenatchi
- Department of Biotechnology, SRM Institute of Science and Technology, Faculty of Science and Humanities, Kattankulathur, Chengalpattu, Tamil Nadu, India
| | - Thanushree A Hegde
- Department of Civil Engineering, NMAM Institute of Technology, Nitte, Karnataka, 574110, India
| | - Thangamani R
- Department of Civil Engineering, NMAM Institute of Technology, Nitte, Karnataka, 574110, India
| | - H T Nguyen
- Institute of Research and Development, Duy Tan University, Da Nang, Viet Nam; School of Engineering & Technology, Duy Tan University, Da Nang, Viet Nam
| | - Arivalagan Pugazhendhi
- Institute of Research and Development, Duy Tan University, Da Nang, Viet Nam; School of Engineering & Technology, Duy Tan University, Da Nang, Viet Nam.
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Alfonso S, Blanc M, Cousin X, Bégout ML. Exposure of zebrafish to an environmental mixture of persistent organic pollutants triggers an increase in anxiety-like syndrome but does not affect boldness in unexposed offspring. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:21439-21452. [PMID: 36269479 DOI: 10.1007/s11356-022-23689-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants (POPs) that are present as complex mixtures in all environmental compartments, including aquatic ecosystems. However, little is known about the effects of such complex mixtures on teleost behaviour. In this study, zebrafish (Danio rerio) were chronically exposed to an environmentally relevant mixture (MIX) containing 22 PCB and 7 PBDE congeners through diet from 5 days post fertilization onwards. MIX-exposed F0 fish produced offspring (F1 and F2 generations) that were fed using plain food and grown until adulthood. In each generation, five behavioural traits (i.e. boldness, activity, sociality, exploration and anxiety) were evaluated by the mean of different experimental set-ups. Two distinct behavioural syndromes were identified: boldness, positively correlated to activity and exploration; and anxiety, associated with low sociality. F0 fish did not display any behavioural disruption resulting from POP exposure whereas F1 MIX fish were bolder than fish from other generations but did not differ significantly from F1 controls. F2 MIX fish displayed a higher anxiety syndrome than F2 controls. This is of particular importance since such behavioural changes in offspring generations may have persistent ecological consequences, may affect fitness and hence cause detrimental effects on wild fish populations exposed to POP mixtures.
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Affiliation(s)
- Sébastien Alfonso
- MARBEC, CNRS, Ifremer, IRD, INRAE, University Montpellier, Route de Maguelone, 34250, Palavas, France.
- COISPA Tecnologia & Ricerca, Via dei trulli 18/20, Torre a Mare, 70126, Bari, Italy.
| | - Mélanie Blanc
- MARBEC, CNRS, Ifremer, IRD, INRAE, University Montpellier, Route de Maguelone, 34250, Palavas, France
| | - Xavier Cousin
- MARBEC, CNRS, Ifremer, IRD, INRAE, University Montpellier, Route de Maguelone, 34250, Palavas, France
| | - Marie-Laure Bégout
- MARBEC, CNRS, Ifremer, IRD, INRAE, University Montpellier, Route de Maguelone, 34250, Palavas, France
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Fernandes AR, Kilanowicz A, Stragierowicz J, Klimczak M, Falandysz J. The toxicological profile of polychlorinated naphthalenes (PCNs). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 837:155764. [PMID: 35545163 DOI: 10.1016/j.scitotenv.2022.155764] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/05/2022] [Accepted: 05/03/2022] [Indexed: 06/15/2023]
Abstract
The legacy of polychlorinated naphthalenes (PCNs) manufactured during the last century continues to persist in the environment, food and humans. Metrological advances have improved characterisation of these occurrences, enabling studies on the effects of exposure to focus on congener groups and individual PCNs. Liver and adipose tissue show the highest retention but significant levels of PCNs are also retained by the brain and nervous system. Molecular configuration appears to influence tissue disposition as well as retention, favouring the higher chlorinated (≥ four chlorines) PCNs while most lower chlorinated molecules readily undergo hydroxylation and excretion through the renal system. Exposure to PCNs reportedly provokes a wide spectrum of adverse effects that range from hepatotoxicity, neurotoxicity and immune response suppression along with endocrine disruption leading to reproductive disorders and embryotoxicity. A number of PCNs, particularly hexachloronaphthalene congeners, elicit AhR mediated responses that are similar to, and occur within similar potency ranges as most dioxin-like polychlorinated biphenyls (PCBs) and some chlorinated dibenzo-p-dioxins and furans (PCDD/Fs), suggesting a relationship based on molecular size and configuration between these contaminants. Most toxicological responses generally appear to be associated with higher chlorinated PCNs. The most profound effects such as serious and sometimes fatal liver disease, chloracne, and wasting syndrome resulted either from earlier episodes of occupational exposure in humans or from acute experimental dosing of animals at levels that reflected these exposures. However, since the restriction of manufacture and controls on inadvertent production (during combustion processes), the principal route of human and animal exposure is likely to be dietary intake. Therefore, further investigations should include the effects of chronic lower level intake of higher chlorinated PCN congeners that persist in the human diet and subsequently in human and animal tissues. PCNs in the diet should be evaluated cumulatively with other similarly occurring dioxin-like contaminants.
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Affiliation(s)
- Alwyn R Fernandes
- School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
| | - Anna Kilanowicz
- Department of Toxicology, Medical University of Lodz, Muszyńskiego 1, 90-15 Łódź, Poland
| | - Joanna Stragierowicz
- Department of Toxicology, Medical University of Lodz, Muszyńskiego 1, 90-15 Łódź, Poland
| | - Michał Klimczak
- Department of Toxicology, Medical University of Lodz, Muszyńskiego 1, 90-15 Łódź, Poland
| | - Jerzy Falandysz
- Department of Toxicology, Medical University of Lodz, Muszyńskiego 1, 90-15 Łódź, Poland
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Prenatal Environmental Exposure to Persistent Organic Pollutants and Reproductive Hormone Profile and Pubertal Development in Dutch Adolescents. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19159423. [PMID: 35954780 PMCID: PMC9367960 DOI: 10.3390/ijerph19159423] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/24/2022] [Accepted: 07/28/2022] [Indexed: 12/04/2022]
Abstract
Persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), may interfere with hormonal processes. Knowledge about the effects of prenatal exposure to PCBs and their hydroxylated metabolites (OH-PCBs) on pubertal development is limited. Therefore, the aim of the current study was to determine whether prenatal environmental PCB and OH-PCB exposure are associated with reproductive hormone levels and pubertal characteristics in 13- to 15-year-old children. In this Dutch observational cohort study, 194 mother–infant pairs were included (1998–2002). Maternal pregnancy serum levels of PCBs, OH-PCBs, and other POPs were measured. At follow-up (2014–2016), we measured serum or plasma levels of reproductive hormones in their children. We assessed Tanner stages and testicular volume (by clinician or standardized self-assessment), and participants completed questionnaires on pubertal onset. In total, 101 adolescents (14.4 ± 0.8 years; 53.7% of invited) participated, and 55 were boys. In boys, higher prenatal PCB levels were associated with higher testosterone levels, higher pubic hair stage, larger testicular volume, and younger age at onset of growth spurt and voice break. In girls, higher prenatal PCB levels were associated with higher stages for breast development. In conclusion, higher prenatal PCB exposure could be associated with more advanced pubertal development in 13- to 15-year-old children.
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Stragierowicz J, Stypuła-Trębas S, Radko L, Posyniak A, Nasiadek M, Klimczak M, Kilanowicz A. An assessment of the estrogenic and androgenic properties of tetra- and hexachloronaphthalene by YES/YAS in vitro assays. CHEMOSPHERE 2021; 263:128006. [PMID: 33297039 DOI: 10.1016/j.chemosphere.2020.128006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/31/2020] [Accepted: 08/13/2020] [Indexed: 06/12/2023]
Abstract
Many persistent organic pollutants (POPs) exhibit endocrine disrupting activity but studies on some POPs, e.g., polychlorinated naphthalenes (PCNs), are very scarce. The present study investigates the (anti)estrogenic and (anti)androgenic activities of 1,2,3,5,6,7-hexachloronaphthalane (PCN67) and 1,3,5,8-tetrachloronaphthalene (PCN43) using the yeast estrogen and androgen reporter bioassays. Among the tested substances, antiestrogenic response was only shown by PCN67. The strongest inhibition of estrogenic activity (up to 17.4%) was observed in the low concentration ranges (5 pM - 0.5 nM) in the presence of 1.5 nM 17β-estradiol. Both tested compounds showed partial estrogenic activity with a hormetic-type response. However, both studied chemicals showed strong antiandrogenic effects: their potency in the presence of 100 nM 17β-testosterone for PCN43 (IC50 = 2.59 μM) and PCN67 (IC50 = 3.14 μM) was approximately twice that of the reference antiandrogen flutamide (IC50 = 6.14 μM). It cannot be excluded that exposure to PCNs, together with other endocrine disrupting chemicals (EDCs), may contribute to the deregulation of sex steroid hormone signaling.
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Affiliation(s)
- Joanna Stragierowicz
- Department of Toxicology, Medical University of Lodz, Muszynskiego 1, 90-151, Lodz, Poland
| | - Sylwia Stypuła-Trębas
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100, Pulawy, Poland
| | - Lidia Radko
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100, Pulawy, Poland
| | - Andrzej Posyniak
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100, Pulawy, Poland
| | - Marzenna Nasiadek
- Department of Toxicology, Medical University of Lodz, Muszynskiego 1, 90-151, Lodz, Poland
| | - Michał Klimczak
- Department of Toxicology, Medical University of Lodz, Muszynskiego 1, 90-151, Lodz, Poland
| | - Anna Kilanowicz
- Department of Toxicology, Medical University of Lodz, Muszynskiego 1, 90-151, Lodz, Poland.
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Laws MJ, Neff AM, Brehm E, Warner GR, Flaws JA. Endocrine disrupting chemicals and reproductive disorders in women, men, and animal models. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2021; 92:151-190. [PMID: 34452686 PMCID: PMC9743013 DOI: 10.1016/bs.apha.2021.03.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
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.
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Pham TN, Nishijo M, Pham TT, Vu HT, Tran NN, Tran AH, Do Q, Takiguchi T, Nishino Y, Nishijo H. Dioxin exposure and sexual dimorphism of gaze behavior in prepubertal Vietnamese children living in Da Nang, a hot spot for dioxin contamination. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 749:141083. [PMID: 32829268 DOI: 10.1016/j.scitotenv.2020.141083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 07/17/2020] [Accepted: 07/17/2020] [Indexed: 06/11/2023]
Abstract
Previous studies have reported that dioxin exposure alters sexual dimorphism of play behavior in pre-pubertal children. We aimed to investigate the effects of perinatal dioxin exposure, indicated by dioxins in breast milk, on sexual dimorphism of gaze behavior after adjusting for salivary testosterone (T). Participants were pre-pubertal children in a hot spot for dioxin contamination originating from herbicide spraying in Vietnam. We used eye tracking to assess gaze behavior in 172 children (100 boys and 72 girls) aged 8-9 years. Two sets of 15 pairs of pictures, one oriented towards boys and one oriented towards girls, containing 5 pairs of toy photos (non-biological stimuli) and 10 pairs of human line drawings (biological stimuli) were shown to all children. The total fixation duration for each picture was extracted using Tobii studio software and a feminine index of gaze behavior was defined as the ratio of the summed fixation duration for the girl- vs boy-oriented versions of each stimuli. When viewing non-biological stimuli, feminine index scores significantly increased with TCDD (β = 0.294) in girls only. For biological stimuli, however, feminine index scores significantly increased with TEQ-PCDD/Fs (β = 0.269) in boys and with TCDD in girls (β = 0.286). These associations were significant even after adjusting for salivary T levels, which were inversely associated with some dioxin congeners in girls. In addition, increased feminine index scores for biological stimuli were associated with lower cognitive scores for hand-movement and word-order tests in boys and for face-recognition tests in girls examined at 5 years of age. In conclusion, these results suggest that perinatal dioxin exposure may increase visual interest in girl-oriented objects through impairment of cognitive abilities in pre-pubertal Vietnamese children. PCDD congeners were associated with gaze behavior independently of T levels in boys, while this was only the case for TCDD levels in girls.
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Affiliation(s)
- Thao Ngoc Pham
- Department of Public Health, Kanazawa Medical University, Japan; Biomedical and Pharmaceutical Research Center, Vietnamese Military Medical University, Viet Nam
| | - Muneko Nishijo
- Department of Public Health, Kanazawa Medical University, Japan.
| | - Tai The Pham
- Biomedical and Pharmaceutical Research Center, Vietnamese Military Medical University, Viet Nam
| | - Hoa Thi Vu
- Department of Public Health, Kanazawa Medical University, Japan
| | | | - Anh Hai Tran
- Biomedical and Pharmaceutical Research Center, Vietnamese Military Medical University, Viet Nam
| | - Quyet Do
- Biomedical and Pharmaceutical Research Center, Vietnamese Military Medical University, Viet Nam
| | | | | | - Hisao Nishijo
- System Emotional Science, Graduate School of Medicine, University of Toyama, Japan
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Abstract
BACKGROUND Brominated flame retardants, including polybrominated biphenyls (PBB), are persistent compounds reported to affect sex hormones in animals; less is known about potential effects in humans. An industrial accident in 1973-1974 exposed Michigan residents to PBB through contaminated food. We examined whether this exposure to PBB had long-term effects on menstrual cycle function. METHODS In 2004-2006, we recruited reproductive-aged women in the Michigan PBB Registry who were not pregnant, lactating, or taking hormonal medications. Participants kept daily diaries and provided daily urine samples for up to 6 months. We assayed the urine samples for estrone 3-glucuronide (E13G), pregnanediol 3-glucuronide (Pd3G), and follicle stimulating hormone (FSH). We fit linear mixed models among women aged 35-42 years to describe the relation between serum PBB levels and log-transformed, creatinine-adjusted daily endocrine levels among women who were premenarchal during the exposure incident in 1973-1974 (n = 70). RESULTS We observed that high (>3.0 parts per billion [ppb]) and medium (>1.0-3.0 ppb) PBB exposure were associated with lower E13G levels across the menstrual cycle and lower FSH levels during the follicular phase, compared with low PBB exposure (≤1.0 ppb). High PBB exposure was also associated with lower Pd3G levels across the cycle compared with low PBB exposure, whereas Pd3G levels were similar in women with medium and low PBB exposure. CONCLUSION Our results are consistent with a hypothesized effect of exposure to an exogenous estrogen agonist but the modest sample size of the study requires cautious interpretation.
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Bala R, Singh V, Rajender S, Singh K. Environment, Lifestyle, and Female Infertility. Reprod Sci 2020; 28:617-638. [DOI: 10.1007/s43032-020-00279-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 07/24/2020] [Indexed: 01/01/2023]
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Lucaccioni L, Trevisani V, Boncompagni A, Marrozzini L, Berardi A, Iughetti L. Minipuberty: Looking Back to Understand Moving Forward. Front Pediatr 2020; 8:612235. [PMID: 33537266 PMCID: PMC7848193 DOI: 10.3389/fped.2020.612235] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/14/2020] [Indexed: 12/20/2022] Open
Abstract
Hypothalamic-pituitary-gonadal (HPG) axis activation occurs three times in life: the first is during fetal life, and has a crucial role in sex determination, the second time is during the first postnatal months of life, and the third is with the onset of puberty. These windows of activation recall the three windows of the "Developmental Origin of Health and Disease" (DOHaD) paradigm and may play a substantial role in several aspects of human development, such as growth, behavior, and neurodevelopment. From the second trimester of pregnancy there is a peak in gonadotropin levels, followed by a decrease toward term and complete suppression at birth. This is due to the negative feedback of placental estrogens. Studies have shown that in this prenatal HPG axis activation, gonadotropin levels display a sex-related pattern which plays a crucial role in sex differentiation of internal and external genitalia. Soon after birth, there is a new increase in LH, FSH, and sex hormone concentrations, both in males and females, due to HPG re-activation. This postnatal activation is known as "minipuberty." The HPG axis activity in infancy demonstrates a pulsatile pattern with hormone levels similar to those of true puberty. We review the studies on the changes of these hormones in infancy and their influence on several aspects of future development, from linear growth to fertility and neurobehavior.
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Affiliation(s)
- Laura Lucaccioni
- Pediatric Unit, Department of Medical and Surgical Sciences of the Mothers, Children and Adults, University of Modena and Reggio Emilia, Modena, Italy
| | - Viola Trevisani
- Department of Medical and Surgical Sciences of the Mothers, Children and Adults, Post Graduate School of Pediatrics, University of Modena and Reggio Emilia, Modena, Italy
| | - Alessandra Boncompagni
- Neonatal Intensive Care Unit, Department of Medical and Surgical Sciences of the Mothers, Children and Adults, University of Modena and Reggio Emilia, Modena, Italy
| | - Lucia Marrozzini
- Department of Medical and Surgical Sciences of the Mothers, Children and Adults, Post Graduate School of Pediatrics, University of Modena and Reggio Emilia, Modena, Italy
| | - Alberto Berardi
- Neonatal Intensive Care Unit, Department of Medical and Surgical Sciences of the Mothers, Children and Adults, University of Modena and Reggio Emilia, Modena, Italy
| | - Lorenzo Iughetti
- Pediatric Unit, Department of Medical and Surgical Sciences of the Mothers, Children and Adults, University of Modena and Reggio Emilia, Modena, Italy.,Department of Medical and Surgical Sciences of the Mothers, Children and Adults, Post Graduate School of Pediatrics, University of Modena and Reggio Emilia, Modena, Italy
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Attfield KR, Pinney SM, Sjödin A, Voss RW, Greenspan LC, Biro FM, Hiatt RA, Kushi LH, Windham GC. Longitudinal study of age of menarche in association with childhood concentrations of persistent organic pollutants. ENVIRONMENTAL RESEARCH 2019; 176:108551. [PMID: 31376650 DOI: 10.1016/j.envres.2019.108551] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Age at female puberty is associated with adult morbidities, including breast cancer and diabetes. Hormonally active chemicals are suspected of altering pubertal timing. We examined whether persistent organic pollutants (POPs) are associated with age at menarche in a longitudinal study. METHODS We analyzed data for females enrolled at age 6-8 years in the Breast Cancer and Environment Research Program from California and Ohio. Participants were followed annually 2004-2013 and provided serum (mean age 7.8 years) for measurement of polychlorinated biphenyl (PCB), organochlorine pesticide (OCP), and polybrominated diphenyl ether (PBDE) concentrations. Age of menarche was assigned based on parental and participant reported dates and ages of menarche. Adjusted hazard ratios (aHRs) for menarchal onset were calculated with Cox proportional regression. Body mass index (BMI), potentially on the causal pathway, was added to parallel analyses. RESULTS Age of menarche was later with higher summed PCB levels (median 11.9 years in quartile 1 [Q1] versus 12.7 in quartile 4 [Q4]) and OCP levels (12.1 years versus 12.4, respectively). When adjusting for all covariates except BMI, higher POP concentrations were associated with later age at menarche (Q4 versus Q1 aHRs: PBDEs 0.75 [95% CI 0.58, 0.97], PCBs 0.67 [95% CI 0.5, 0.89], and OCPs 0.66 [95% CI 0.50, 0.89]). Additional adjustment for BMI attenuated aHRs; PCB aHR approached the null. CONCLUSION Findings revealed later onset of menarche with higher concentrations of certain POPs, possibly through an association with BMI. Altered pubertal timing may have long lasting effects on reproductive health and disease risk, so continued attention is important for understanding the biological processes affected by hormonally active chemicals.
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Affiliation(s)
- Kathleen R Attfield
- California Department of Public Health, Richmond, CA, USA; Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Susan M Pinney
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Andreas Sjödin
- Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Robert W Voss
- California Department of Public Health, Richmond, CA, USA
| | | | - Frank M Biro
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Robert A Hiatt
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
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Chu CP, Wu SW, Huang YJ, Chiang MC, Hsieh ST, Guo YL. Neuroimaging signatures of brain plasticity in adults with prenatal exposure to polychlorinated biphenyls: Altered functional connectivity on functional MRI. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 250:960-968. [PMID: 31085483 DOI: 10.1016/j.envpol.2019.04.105] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/09/2019] [Accepted: 04/22/2019] [Indexed: 06/09/2023]
Abstract
Prenatal exposure to polychlorinated biphenyls (PCBs), persistent organic pollutants in food chains and environment, exerts negative effects on children's cognitive function. To study the long-term effects, we examined cognitive functions in the male children of women with substantial PCB exposure in Taiwan during 1978-1979 and investigated neural basis of cognitive function changes through structural magnetic resonance imaging (MRI) and functional MRI (fMRI), which included resting-state and task-activated fMRI with two paradigms: a 2-back task and a picture rotation task. Ten men aged 30.0 ± 3.7 years with prenatal exposure to PCBs and 11 unexposed controls aged 28.1 ± 3.1 years participated. Both groups had similar cognitive phenotypes and behavioral results. Structural MRI analysis results showed that the PCB group had increased cortical thickness over the right inferior parietal lobule. In the resting-state study, the PCB group showed alterations in the default mode network. During the tasks, the PCB group showed decreased task-induced deactivation signals in cognition-associated brain areas during the 2-back task but enhanced deactivations during the picture rotation task. This study demonstrated altered structural MRI as well as resting and task-related fMRI in men with prenatal PCB exposure, suggesting altered brain plasticity and compensatory neuropsychological performance.
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Affiliation(s)
- Chih-Pang Chu
- Graduate Institute of Brain and Mind Science, National Taiwan University College of Medicine, Taipei, Taiwan; Division of Psychosomatic Medicine, Taipei City Hospital Songde Branch, Taipei, Taiwan; Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan
| | - Shao-Wei Wu
- Graduate Institute of Brain and Mind Science, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan; Department of Anatomy and Cell Biology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yi-Jie Huang
- Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei, Taiwan
| | - Ming-Chang Chiang
- Department of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan
| | - Sung-Tsang Hsieh
- Graduate Institute of Brain and Mind Science, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan; Department of Anatomy and Cell Biology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yue Leon Guo
- Department of Environmental and Occupational Medicine, National Taiwan University and National Taiwan University Hospital, Taipei, Taiwan; Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei, Taiwan; National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli, Taiwan.
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16
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Berghuis SA, Roze E. Prenatal exposure to PCBs and neurological and sexual/pubertal development from birth to adolescence. Curr Probl Pediatr Adolesc Health Care 2019; 49:133-159. [PMID: 31147261 DOI: 10.1016/j.cppeds.2019.04.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Several chemical compounds are resistant to degradation and end up in the food chain. One group of these chemicals is polychlorinated biphenyls (PCBs) which are used as flame retardants and plasticizers. Although PCBs were banned several decades ago, PCBs are still found in environmental media, including in the body of humans. PCBs are transferred from mother to fetus via the placenta during pregnancy. Considering that the prenatal period is a sensitive period during which essential developmental processes take place, exposure to environmental chemicals might have considerable and permanent consequences for outcomes in later life. The aim of this review is to provide an update on the latest insights on the effects of prenatal exposure to PCBs on neurological, sexual and pubertal development in children. We give an overview of recent literature, and discuss it in the light of the findings in a unique Dutch birth cohort, with data on both neurological and pubertal development into adolescence. The findings in the studies included in this review, together with the findings in the Dutch cohort, demonstrate that prenatal exposure to PCBs can interfere with normal child development, not only during the perinatal period, but up to and including adolescence. Higher prenatal exposure to PCBs was found to be both negatively and positively associated with neurodevelopmental outcomes. Regarding pubertal development, higher prenatal PCB exposure was found to be associated with more advanced pubertal development, also in the Dutch cohort, whereas other studies also found delayed pubertal development. These findings raise concern regarding the effects of man-made chemical compounds on child development. They further contribute to the awareness of how environmental chemical compounds can interfere with child development and negatively influence healthy ageing.
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Affiliation(s)
- Sietske Annette Berghuis
- Division of Neonatology, Department of Pediatrics, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Hanzeplein 1, PO Box 30.001, 9713 GZ, Groningen, the Netherlands.
| | - Elise Roze
- Division of Neonatology, Department of Pediatrics, Wilhelmina Children's Hospital, University of Utrecht, University Medical Center Utrecht, Utrecht, the Netherlands
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Guo LC, Pan S, Yu S, Liu T, Xiao J, Zhu B, Qu Y, Huang W, Li M, Li X, Zeng W, Rutherford S, Lin L, Zhang Y, Ma W. Human Sex Hormone Disrupting Effects of New Flame Retardants and Their Interactions with Polychlorinated Biphenyls, Polybrominated Diphenyl Ethers, a Case Study in South China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:13935-13941. [PMID: 30384584 DOI: 10.1021/acs.est.8b01540] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Even though sex hormone disrupting effects of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are widely understood, similar effects associated with new flame retardants (NFRs) have not been so well studied. This study aimed to explore the sex hormone disruption of NFRs and their interactions with PCBs and PBDEs through the conduct of an ecological study in an e-waste dismantling and control region in South China. Questionnaires and blood samples were collected from local adult residents. Results of generalized additive model and linear regression analyses indicate that several species of NFRs showed similar disrupting effects with PBDE congeners on female follicle-stimulating hormone (FSH) and male testosterone. Judged by the curved shape and statistical significance, ΣNFR (sum of 8 species of NFRs) showed stronger disrupting effects on male testosterone and female FSH compared to ΣPBDE (sum of 13 congeners of PBDEs). The interactions induced by NFRs complicated the original sex hormone disruption led by PCBs and PBDEs. The disrupting effects and interactions induced by NFRs decreased female FSH levels in the exposed group. Comprehensive evaluation is needed to provide the evidence base for judging the health risks arising from the increased usage of NFRs.
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Affiliation(s)
- Ling-Chuan Guo
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Shangxia Pan
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Shengbing Yu
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Tao Liu
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Jianpeng Xiao
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
- School of Public Health , Southern Medical University , Guangzhou 510515 , China
| | - Binghui Zhu
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Yabin Qu
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Weixiong Huang
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Min Li
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Xing Li
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
- School of Public Health , Southern Medical University , Guangzhou 510515 , China
| | - Weilin Zeng
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Shannon Rutherford
- Centre for Environment and Population Health, School of Medicine , Griffith University , Brisbane , Queensland 4111 , Australia
| | - Lifeng Lin
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Yonghui Zhang
- Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
| | - Wenjun Ma
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention , Guangzhou 511430 , China
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Stragierowicz J, Bruchajzer E, Daragó A, Nasiadek M, Kilanowicz A. Hexachloronaphthalene (HxCN) as a potential endocrine disruptor in female rats. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 243:1026-1035. [PMID: 30253293 DOI: 10.1016/j.envpol.2018.09.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 09/05/2018] [Accepted: 09/07/2018] [Indexed: 06/08/2023]
Abstract
Hexachloronaphthalene (HxCN) is one of the most toxic and most bioaccumulative congeners of polychlorinated naphthalenes (PCNs) known to be present in animal and human adipose tissue. Unfortunately, little data is available regarding the negative effect of PCNs on endocrine function. The aim of the study was to investigate the direct influence of subacute (two and four-week) and subchronic (13-week) daily oral exposure of female rats to 30, 100 and 300 μg kg b.w.-1 HxCN on ovarian, thyroid function and neurotransmitters level. The levels of selected sex hormones (progesterone: P and estradiol: E2) in the serum and uterus, regularity of estrous cycle, levels of thyroid hormones (fT3 and fT4), TSH, γ-aminobutyric acid and glutamate levels in selected brain areas and the activity of CYP1A1 and CYP2B in the liver were examined. Estrogenic action (elevated E2 concentration in the uterus and serum) was observed only after subacute exposure, and antiestrogenic activity (decreased E2 level and uterus weight) after 13 weeks administration of 300 μg kg b.w.-1 day-1. Subchronic administration of HxCN significantly lengthens the estrous cycle, by up to almost 50%, and increases the number of irregular cycles. In addition, increased TSH and decreased fT4 serum levels were observed after all doses and durations of exposure to HxCN. Only subacute exposure led to a significant decrease in the level of examined neurotransmitters in all analyzed structures. Additionally, exposure to low doses of HxCN appears to lead to strong induction of CYP1A1 in a liver. It can be hypothesized that HxCN produces effects which are very similar to those caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and dioxin-like compounds (DLCs), particularly concerning endocrine and estrous cyclicity disorders. Therefore, HxCN exposure may exert unexpected effects on female fecundity among the general population.
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Affiliation(s)
- Joanna Stragierowicz
- Department of Toxicology, Faculty of Pharmacy, Medical University, Muszynskiego 1, 90-151, Lodz, Poland.
| | - Elżbieta Bruchajzer
- Department of Toxicology, Faculty of Pharmacy, Medical University, Muszynskiego 1, 90-151, Lodz, Poland.
| | - Adam Daragó
- Department of Toxicology, Faculty of Pharmacy, Medical University, Muszynskiego 1, 90-151, Lodz, Poland.
| | - Marzenna Nasiadek
- Department of Toxicology, Faculty of Pharmacy, Medical University, Muszynskiego 1, 90-151, Lodz, Poland.
| | - Anna Kilanowicz
- Department of Toxicology, Faculty of Pharmacy, Medical University, Muszynskiego 1, 90-151, Lodz, Poland.
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19
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Araki A, Itoh S, Miyashita C, Minatoya M, Kishi R. [Environmental Chemical Exposure and Its Effects on Infants' Reproductive Hormones]. Nihon Eiseigaku Zasshi 2018; 73:313-321. [PMID: 30270299 DOI: 10.1265/jjh.73.313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In recent years, the birthrate has been continuously declining in Japan. The main causes of the decline are social factors. On the other hand, there is increasing evidence that many environmental chemicals show endocrine disrupting properties. Thus, we hypothesized that exposure to these chemicals would also be a causal for the fertility crisis. In this review, we examined current evidence that focused on environmental chemical exposure in utero and its association with reproductive hormones in children. We have included the findings from a prospective birth cohorts, the Hokkaido Study on Environment and Children's Health Sapporo cohort. According to the literature, environmental chemical levels in utero, such as polychlorinated biphenyl, dioxins, perfluorinated chemical substances, phthalates, and bisphenol A were somewhat associated with the levels of reproductive hormones, such as testosterone, estradiol, progesterone, inhibin B, and insulin-like factor-3 in cord blood, in early childhood and adolescence. The literature also suggests the association between exposure to these chemicals and brain-sexual differentiation or the anogenital distance, which suggests the disruption of androgen shower during the developmental stage in the fetal period. There are still knowledge gaps on whether these hormones at an early stage affect the pubertal development and reproductive functions in later life. In addition, alternative chemicals are produced after banning one type. The health effects of alternative chemicals should be evaluated. Effects of exposure to a mixture of the chemicals should also be examined in future studies. In conclusion, the prevention of environmental chemical hazards in relation to human reproductive function is important. It would be one of the countermeasures to the falling birthrate caused by fertility issues.
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Affiliation(s)
- Atsuko Araki
- Hokkaido University Center for Environmental and Health Sciences
| | - Sachiko Itoh
- Hokkaido University Center for Environmental and Health Sciences
| | | | - Machiko Minatoya
- Hokkaido University Center for Environmental and Health Sciences
| | - Reiko Kishi
- Hokkaido University Center for Environmental and Health Sciences
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20
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Kristensen SL, Ramlau-Hansen CH, Ernst E, Olsen SF, Bonde JP, Vested A, Halldorsson TI, Rantakokko P, Kiviranta H, Toft G. Prenatal exposure to persistent organochlorine pollutants and female reproductive function in young adulthood. ENVIRONMENT INTERNATIONAL 2016; 92-93:366-72. [PMID: 27132162 DOI: 10.1016/j.envint.2016.04.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/14/2016] [Accepted: 04/14/2016] [Indexed: 05/26/2023]
Abstract
BACKGROUND The biopersistent organochlorine pollutants dichlorodiphenyldichloroethylene (p,p'-DDE), hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) can be detected in humans worldwide. The chemicals can cross the placenta and may interfere with endogenous hormonal homeostasis. OBJECTIVES To investigate effects on female reproduction following intrauterine exposure to selected biopersistent organochlorines. METHODS We used data from a Danish pregnancy cohort with follow-up on 436 eligible daughters at approximately 20years of age. Information on age of menarche (n=335), menstrual cycle length (n=230) and serum concentrations of reproductive hormones (n=243) was obtained. Number of antral follicles was counted by vaginal ultrasound (n=147). Of 244 daughters who attended clinical examination, 170 used hormonal contraceptives and 74 were non-users. Concentrations of p,p'-DDE, HCB and six PCB congeners were analysed in maternal serum samples obtained in pregnancy week 30. RESULTS Age of menarche and menstrual cycle length were found not to be statistically significant associated with prenatal organochlorine exposure. Among non-users of hormonal contraceptives with information on antral follicle number (n=43), daughters exposed to the highest tertile of p,p'-DDE had 28% (95% confidence interval (95% CI): 5; 46%) lower follicle number compared to the low-level exposed reference group. Those exposed to medium and higher levels of HCB had 30% (95% CI: 5; 48%) and 28% (95% CI: 7; 44%) lower follicle number compared to the reference group. Furthermore, maternal serum HCB concentrations were inversely associated with free androgen index among non-users of hormonal contraceptives (n=73). These associations were not found in users of hormonal contraceptives. CONCLUSIONS Among non-users of hormonal contraceptives, we found indications of adverse long-term effects on female reproduction following prenatal exposure to biopersistent organochlorines. These findings may have wide implications for public health as intrauterine exposure occurs worldwide.
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Affiliation(s)
- Susanne Lund Kristensen
- Danish Ramazzini Centre, Department of Occupational Medicine, Aarhus University Hospital, Aarhus, Denmark; Department of Obstetrics and Gynecology, Regional Hospital of Randers, Denmark.
| | | | - Erik Ernst
- Department of Gynaecology and Obstetrics, Aarhus University Hospital, and Institute of Anatomy, University of Aarhus, Aarhus, Denmark
| | | | - Jens Peter Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg Hospital of Copenhagen University, Copenhagen, Denmark
| | - Anne Vested
- Danish Ramazzini Centre, Department of Occupational Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Thorhallur Ingi Halldorsson
- Centre for Fetal Programming, Statens Serum Institut, Copenhagen, Denmark; Faculty of Food Science and Nutrition, University of Iceland, Reykjavik, Iceland
| | - Panu Rantakokko
- National Institute for Health and Welfare, Department of Environmental Health, Chemical Exposure Unit, Kuopio, Finland
| | - Hannu Kiviranta
- National Institute for Health and Welfare, Department of Environmental Health, Chemical Exposure Unit, Kuopio, Finland
| | - Gunnar Toft
- Danish Ramazzini Centre, Department of Occupational Medicine, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark
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Parent AS, Franssen D, Fudvoye J, Gérard A, Bourguignon JP. Developmental variations in environmental influences including endocrine disruptors on pubertal timing and neuroendocrine control: Revision of human observations and mechanistic insight from rodents. Front Neuroendocrinol 2015; 38:12-36. [PMID: 25592640 DOI: 10.1016/j.yfrne.2014.12.004] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 12/13/2014] [Accepted: 12/15/2014] [Indexed: 12/21/2022]
Abstract
Puberty presents remarkable individual differences in timing reaching over 5 years in humans. We put emphasis on the two edges of the age distribution of pubertal signs in humans and point to an extended distribution towards earliness for initial pubertal stages and towards lateness for final pubertal stages. Such distortion of distribution is a recent phenomenon. This suggests changing environmental influences including the possible role of nutrition, stress and endocrine disruptors. Our ability to assess neuroendocrine effects and mechanisms is very limited in humans. Using the rodent as a model, we examine the impact of environmental factors on the individual variations in pubertal timing and the possible underlying mechanisms. The capacity of environmental factors to shape functioning of the neuroendocrine system is thought to be maximal during fetal and early postnatal life and possibly less important when approaching the time of onset of puberty.
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Affiliation(s)
- Anne-Simone Parent
- Developmental Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Sart-Tilman, B-4000 Liège, Belgium; Department of Pediatrics, CHU de Liège, Rue de Gaillarmont 600, B-4032 Chênée, Belgium
| | - Delphine Franssen
- Developmental Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Sart-Tilman, B-4000 Liège, Belgium
| | - Julie Fudvoye
- Developmental Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Sart-Tilman, B-4000 Liège, Belgium; Department of Pediatrics, CHU de Liège, Rue de Gaillarmont 600, B-4032 Chênée, Belgium
| | - Arlette Gérard
- Developmental Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Sart-Tilman, B-4000 Liège, Belgium; Department of Pediatrics, CHU de Liège, Rue de Gaillarmont 600, B-4032 Chênée, Belgium
| | - Jean-Pierre Bourguignon
- Developmental Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Sart-Tilman, B-4000 Liège, Belgium; Department of Pediatrics, CHU de Liège, Rue de Gaillarmont 600, B-4032 Chênée, Belgium.
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22
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Croes K, Den Hond E, Bruckers L, Loots I, Morrens B, Nelen V, Colles A, Schoeters G, Sioen I, Covaci A, Vandermarken T, Van Larebeke N, Baeyens W. Monitoring chlorinated persistent organic pollutants in adolescents in Flanders (Belgium): concentrations, trends and dose-effect relationships (FLEHS II). ENVIRONMENT INTERNATIONAL 2014; 71:20-28. [PMID: 24950161 DOI: 10.1016/j.envint.2014.05.022] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 05/27/2014] [Accepted: 05/27/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND In 2007, the second cycle of the Flemish human biomonitoring survey started, with a main focus on 14-15 year-old adolescents. OBJECTIVES The main objectives were generating reference values for exposure markers, determining the pollution pressure in industrial hotspots and establishing dose-effect relationships between exposure to pollutants and hormone levels, sexual development, asthma and allergy, genotoxic and hematological markers. METHODS Geometric means with 95% confidence intervals (CI) were calculated for a reference population of 200 14-15 year-old adolescents. Stepwise multiple regression analyses with correction for confounders and covariates were performed to establish dose-effect relationships. RESULTS Geometric mean concentrations (with 95% CI) of 49.6 (45.7, 53.8), 70.8 (63.6, 78.8) and 8.34 (7.76, 8.97) n gg(-1) lipid for the sum of PCB 138, 153 and 180, p,p'-DDE and HCB were respectively 23%, 26% and 60% lower than those obtained five years earlier. Geometric mean concentrations of 108 (101, 114) and 32.1 (30.1, 34.2) pgCALUX-BEQg(-1) lipid were observed for the PCDD/Fs and dioxin-like PCBs, respectively. Multiple dose-effect relationships were observed between POPs and several effect markers, including positive (boys) and negative (girls) associations with data on sexual development and positive associations with asthma, animal allergy and free thyroxine (boys and girls). CONCLUSIONS Our findings suggest that chlorinated POP concentrations are decreasing over time and that even relatively low concentrations are associated with biological effects.
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Affiliation(s)
- Kim Croes
- Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium.
| | | | - Liesbeth Bruckers
- Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Hasselt, Belgium
| | - Ilse Loots
- Political and Social Sciences, University of Antwerp, Antwerp, Belgium
| | - Bert Morrens
- Political and Social Sciences, University of Antwerp, Antwerp, Belgium
| | - Vera Nelen
- Provincial Institute for Hygiene, Antwerp, Belgium
| | - Ann Colles
- Environmental Health and Risk, VITO, Mol, Belgium
| | | | - Isabelle Sioen
- Department of Public Health, Ghent University, Ghent, Belgium
| | - Adrian Covaci
- Toxicological Centre, University of Antwerp, Antwerp, Belgium
| | - Tara Vandermarken
- Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium
| | - Nicolas Van Larebeke
- Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium
| | - Willy Baeyens
- Department of Analytical, Environmental and Geo-Chemistry (AMGC), Vrije Universiteit Brussel, Brussels, Belgium
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Schell LM, Gallo MV, Deane GD, Nelder KR, DeCaprio AP, Jacobs A. Relationships of polychlorinated biphenyls and dichlorodiphenyldichloroethylene (p,p'-DDE) with testosterone levels in adolescent males. ENVIRONMENTAL HEALTH PERSPECTIVES 2014; 122:304-309. [PMID: 24398050 PMCID: PMC3948020 DOI: 10.1289/ehp.1205984] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 12/20/2013] [Indexed: 05/29/2023]
Abstract
BACKGROUND Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized. OBJECTIVES In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to < 17 years of age with documented toxicant exposures. METHODS Data were collected between February 1996 and January 2000. Fasting blood specimens were collected before breakfast by trained Akwesasne Mohawk staff. Multivariable regression models were used to estimates associations between toxicants and serum testosterone, adjusted for other toxicants, Tanner stage, and potential confounders. RESULTS The sum of 16 PCB congeners (Σ16PCBs) that were detected in ≥ 50% of the population was significantly and negatively associated with serum testosterone levels, such that a 10% change in exposure was associated with a 5.6% decrease in testosterone (95% CI: -10.8, -0.5%). Of the 16 congeners, the more persistent ones (Σ8PerPCBs) were related to testosterone, whereas the less persistent ones, possibly reflecting more recent exposure, were not. When PCB congeners were subgrouped, the association was significant for the sum of eight more persistent PCBs (5.7% decrease; 95% CI: -11, -0.4%), and stronger than the sum of six less persistent congeners (3.1% decrease; 95% CI: -7.2, 0.9%). p,p´-DDE was positively but not significantly associated with serum testosterone (5.2% increase with a 10% increase in exposure; 95% CI: -0.5, 10.9%). Neither lead nor HCB was significantly associated with testosterone levels. CONCLUSIONS Exposure to PCBs, particularly the more highly persistent congeners, may negatively influence testosterone levels among adolescent males. The positive relationship between p,p´-DDE and testosterone indicates that not all POPs act similarly. CITATION Schell LM, Gallo MV, Deane GD, Nelder KR, DeCaprio AP, Jacobs A; Akwesasne Task Force on the Environment. 2014. Relationships of polychlorinated biphenyls and dichlorodiphenyldichloroethylene (p,p´-DDE) with testosterone levels in adolescent males. Environ Health Perspect 122:304-309; http://dx.doi.org/10.1289/ehp.1205984.
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Bourguignon JP, Franssen D, Gérard A, Janssen S, Pinson A, Naveau E, Parent AS. Early neuroendocrine disruption in hypothalamus and hippocampus: developmental effects including female sexual maturation and implications for endocrine disrupting chemical screening. J Neuroendocrinol 2013; 25:1079-87. [PMID: 24028442 DOI: 10.1111/jne.12107] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 08/03/2013] [Accepted: 09/05/2013] [Indexed: 01/25/2023]
Abstract
The timing of puberty has been mainly studied in females for several reasons, including the possible evaluation of a precise timer (i.e. menarcheal age) and concerns with respect to the high prevalence of precocity in females as opposed to males. Human evidence of altered female pubertal timing after exposure to endocrine disrupting chemicals (EDCs) is equivocal. Among the limiting factors, most studies evaluate exposure to single EDCs at the time of puberty and hardly assess the impact of lifelong exposure to mixtures of EDCs. Some rodent and ovine studies indicate a possible role of foetal and neonatal exposure to EDCs, in accordance with the concept of an early origin of health and disease. Such effects possibly involve neuroendocrine mechanisms because the hypothalamus is a site where homeostasis of reproduction, as well as control of energy balance, is programmed and regulated. In our previous studies, pulsatile gonadotrophin-releasing hormone (GnRH) secretion control via oestrogen, glutamate and aryl hydrocarbon receptors was shown to be involved in the mechanism of sexual precocity after early postnatal exposure to the insecticide dichlorodiphenyltrichloroethane. Very recently, we have shown that neonatal exposure to the potent synthetic oestrogen diethylstilbestrol (DES) is followed by early or delayed puberty depending on the dose, with consistent changes in developmental increase of GnRH pulse frequency. Moreover, DES results in reduced leptin stimulation of GnRH secretion in vitro, an effect that is additive with prenatal food restriction. Thus, using puberty as an endpoint of the effects of EDC, it appears necessary to consider pre- and perinatal exposure to low doses and to pay attention to the other conditions of prenatal life, such as energy availability, keeping in mind the possibility that puberty could not only be advanced, but also delayed through neuroendocrine mechanisms.
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Affiliation(s)
- J-P Bourguignon
- Developmental Neuroendocrinology Unit, GIGA Neurosciences, University of Liège, Liège, Belgium; Department of Pediatrics, CHU, Liège, Belgium
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Abstract
Endocrine disruptors are substances commonly encountered in every setting and condition in the modern world. It is virtually impossible to avoid the contact with these chemical compounds in our daily life. Molecules defined as endocrine disruptors constitute an extremely heterogeneous group and include synthetic chemicals used as industrial solvents/lubricants and their by-products. Natural chemicals found in human and animal food (phytoestrogens) also act as endocrine disruptors. Different from adults, children are not exposed only to chemical toxins in the environment but may also be exposed during their intrauterine life. Hundreds of toxic substances, which include neuro-immune and endocrine toxic chemical components that may influence the critical steps of hormonal, neurological and immunological development, may affect the fetus via the placental cord and these substances may be excreted in the meconium. Children and especially newborns are more sensitive to environmental toxins compared to adults. Metabolic pathways are immature, especially in the first months of life. The ability of the newborn to metabolize, detoxify and eliminate many toxins is different from that of the adults. Although exposures occur during fetal or neonatal period, their effects may sometimes be observed in later years. Further studies are needed to clarify the effects of these substances on the endocrine system and to provide evidence for preventive measures.
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Affiliation(s)
- Tolga Ünüvar
- T.C. Ministry of Health, İstanbul Kanuni Sultan Süleyman, Training and Research Hospital, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Atilla Büyükgebiz
- Bilim University Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
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Buck Louis GM, Rios LI, McLain A, Cooney MA, Kostyniak PJ, Sundaram R. Persistent organochlorine pollutants and menstrual cycle characteristics. CHEMOSPHERE 2011; 85:1742-8. [PMID: 22018858 PMCID: PMC4143889 DOI: 10.1016/j.chemosphere.2011.09.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 08/10/2011] [Accepted: 09/22/2011] [Indexed: 05/24/2023]
Abstract
An evolving body of evidence suggests an adverse relation between persistent organochlorine pollutants (POPs) and menstruation, though prospective longitudinal measurement of menses is limited and served as the impetus for study. We prospectively assessed the relation between a mixture of persistent organochlorine compounds and menstrual cycle length and duration of bleeding in a cohort of women attempting to become pregnant. Eighty-three (83%) women contributing 447 cycles for analysis provided a blood specimen for the quantification of 76 polychlorinated biphenyls and seven organochlorine pesticides, and completed daily diaries on menstruation until a human chorionic gonadotropin confirmed pregnancy or 12 menstrual cycles without conception. Gas chromatography with electron capture detection was used to quantify concentrations (ng g(-1)serum); enzymatic methods were used to quantify serum lipids (mg dL(-1)). A linear regression model with a mixture distribution was used to identify chemicals grouped by purported biologic activity that significantly affected menstrual cycle length and duration of bleeding adjusting for age at menarche and enrollment, body mass index, and cigarette smoking. A significant 3-d increase in cycle length was observed for women in the highest tertile of estrogenic PCB congeners relative to the lowest tertile (β=3.20; 95% CI 0.36, 6.04). A significant reduction in bleeding (<1 d) was observed among women in the highest versus lowest tertile of aromatic fungicide exposure (γ=-0.15; 95% CI -0.29, -0.00). Select POPs were associated with changes in menstruation underscoring the importance of assessing chemical mixtures for female fecundity.
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Affiliation(s)
- Germaine M Buck Louis
- Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, MD 20852, USA.
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Özen S, Darcan Ş. Effects of environmental endocrine disruptors on pubertal development. J Clin Res Pediatr Endocrinol 2011; 3:1-6. [PMID: 21448326 PMCID: PMC3065309 DOI: 10.4274/jcrpe.v3i1.01] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 01/06/2011] [Indexed: 12/20/2022] Open
Abstract
The onset and course of puberty are under the control of the neuroendocrine system. Factors affecting the timing and regulation of the functions of this system may alter the onset and course of puberty. Several environmental endocrine disruptors (EDs) with significant influences on the normal course of puberty have been identified. Numerous animal and human studies concerning EDs have been conducted showing that these substances may extensively affect human health; nevertheless, there are still several issues that remain to be clarified. In this paper, the available evidence from animal and human studies on the effects of environmental EDs with the potential to cause precocious or delayed puberty was reviewed.
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Affiliation(s)
- Samim Özen
- Pediatric Endocrinology Unit, Mersin Children Hospital, Mersin, Turkey.
| | - Şükran Darcan
- Department of Pediatric Endocrinology and Metabolism, Ege University School of Medicine, Izmir, Turkey
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Yang CY, Huang TS, Lin KC, Kuo P, Tsai PC, Guo YL. Menstrual effects among women exposed to polychlorinated biphenyls and dibenzofurans. ENVIRONMENTAL RESEARCH 2011; 111:288-294. [PMID: 21186023 DOI: 10.1016/j.envres.2010.11.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2010] [Revised: 11/16/2010] [Accepted: 11/24/2010] [Indexed: 05/30/2023]
Abstract
BACKGROUND Polychlorinated biphenyls (PCBs), dibenzofurans (PCDFs), and dibenzo-dioxins (PCDDs) may affect the female reproductive system in humans. A mass poisoning occurred in Taiwan due to PCBs/PCDFs-contaminated cooking oil, and was called the Yucheng (oil-disease in Chinese). We aimed to determine whether Yucheng women were affected in their menstruation. METHODS After the event, we followed the exposed individuals and an age-matched neighborhood reference group. Menstrual cycle characteristics and age at menarche were obtained by a telephone interview. We used multiple linear and logistic regression to examine the association between PCBs/PCDFs and menstrual cycle characteristics, after adjusting for confounding factors. RESULTS Totally 445 women responded satisfactorily and were included in the analyses of menstrual characteristics. Menstrual cycle irregularity and dysmenorrheal did not differ between Yucheng and referents. Yucheng women's menstrual cycles were 0.5 (95% CI: 0.0-0.5; p=0.03) days shorter than those of the referents. The Yucheng women with skin lesions caused by PCBs/PCDFs were more prominently affected, with the cycles 1.2 days shorter than the referents. Yucheng women exposed to PCBs/PCDFs at the premenacheal period had reduced cycle length (-0.7 day, 95% CI: -1.4 to 0.0; p=0.04) and longer days of menstrual flow (0.5 day, 95% CI: 0.0-1.0; p=0.04). Among those women who were exposed at an age of 5-9 years, menarche started slightly earlier with borderline significance. CONCLUSIONS Shorter menstrual cycle length and a longer duration of bleeding in each cycle were found among women previously exposed to PCBs/PCDFs. These effects were more obviously observed among those exposed at premenarcheal ages.
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Affiliation(s)
- Chiu-Yueh Yang
- Department of Health Business Administration, Hung-Kuang University, Taichung, Taiwan, ROC
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Walvoord EC. The timing of puberty: is it changing? Does it matter? J Adolesc Health 2010; 47:433-9. [PMID: 20970077 DOI: 10.1016/j.jadohealth.2010.05.018] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 05/21/2010] [Accepted: 05/21/2010] [Indexed: 12/16/2022]
Abstract
Whether the secular trend of a decreasing age of puberty has continued over the past 50 years remains controversial. Data that had been classically used to address this issue are reviewed and large epidemiologic studies, which had not previously been included, are now considered to challenge the conclusions of prior debates of this topic. The effect and timing of excessive weight gain are discussed in detail and recent observations about the opposing effects of obesity on the pubertal timing of girls versus boys are considered. The second half of the review examines both the causes and the long-term health consequences of early puberty, touching on the possible effect of stress and endocrine-disrupting chemicals along with the risks of reproductive cancers, metabolic syndrome, and psychosocial consequences during adolescence and beyond.
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Affiliation(s)
- Emily C Walvoord
- Section of Endocrinology and Diabetology, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA.
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Bourguignon JP, Rasier G, Lebrethon MC, Gérard A, Naveau E, Parent AS. Neuroendocrine disruption of pubertal timing and interactions between homeostasis of reproduction and energy balance. Mol Cell Endocrinol 2010; 324:110-20. [PMID: 20206664 DOI: 10.1016/j.mce.2010.02.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Revised: 02/23/2010] [Accepted: 02/23/2010] [Indexed: 02/02/2023]
Abstract
The involvement of environmental factors such as endocrine disrupting chemicals (EDCs) in the timing of onset of puberty is suggested by recent changes in age at onset of puberty and pattern of distribution that are variable among countries, as well as new forms of sexual precocity after migration. However, the evidence of association between early or late pubertal timing and exposure to EDCs is weak in humans, possibly due to heterogeneity of effects likely involving mixtures and incapacity to assess fetal or neonatal exposure retrospectively. The neuroendocrine system which is crucial for physiological onset of puberty is targeted by EDCs. These compounds also act directly in the gonads and peripheral sex-steroid sensitive tissues. Feedbacks add to the complexity of regulation so that changes in pubertal timing caused by EDCs can involve both central and peripheral mechanisms. In experimental conditions, several neuroendocrine endpoints are affected by EDCs though only few studies including from our laboratory aimed at EDC involvement in the pathophysiology of early sexual maturation. Recent observations support the concept that EDC cause disturbed energy balance and account for the obesity epidemic. Several aspects are linking this system and the reproductive axis: coexisting neuroendocrine and peripheral effects, dependency on fetal/neonatal programming and the many factors cross-linking the two systems, for instance leptin, adiponectin, Agouti Related Peptide (AgRP). This opens perspectives for future research and, hopefully, measures preventing the disturbances of homeostasis caused by EDCs.
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Affiliation(s)
- Jean-Pierre Bourguignon
- Developmental Neuroendocrinology Unit, GIGA Neurosciences, University of Liège and Department of Pediatrics, CHU de Liège, Belgium.
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Development and characterization of new polyclonal antibodies specific for three polychlorinated biphenyls. CHINESE CHEM LETT 2009. [DOI: 10.1016/j.cclet.2008.12.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Crain DA, Janssen SJ, Edwards TM, Heindel J, Ho SM, Hunt P, Iguchi T, Juul A, McLachlan JA, Schwartz J, Skakkebaek N, Soto AM, Swan S, Walker C, Woodruff TK, Woodruff TJ, Giudice LC, Guillette LJ. Female reproductive disorders: the roles of endocrine-disrupting compounds and developmental timing. Fertil Steril 2008; 90:911-40. [PMID: 18929049 DOI: 10.1016/j.fertnstert.2008.08.067] [Citation(s) in RCA: 300] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Accepted: 08/13/2008] [Indexed: 12/21/2022]
Abstract
OBJECTIVE To evaluate the possible role of endocrine-disrupting compounds (EDCs) on female reproductive disorders emphasizing developmental plasticity and the complexity of endocrine-dependent ontogeny of reproductive organs. Declining conception rates and the high incidence of female reproductive disruptions warrant evaluation of the impact of EDCs on female reproductive health. DESIGN Publications related to the contribution of EDCs to disorders of the ovary (aneuploidy, polycystic ovary syndrome, and altered cyclicity), uterus (endometriosis, uterine fibroids, fetal growth restriction, and pregnancy loss), breast (breast cancer, reduced duration of lactation), and pubertal timing were identified, reviewed, and summarized at a workshop. CONCLUSION(S) The data reviewed illustrate that EDCs contribute to numerous human female reproductive disorders and emphasize the sensitivity of early life-stage exposures. Many research gaps are identified that limit full understanding of the contribution of EDCs to female reproductive problems. Moreover, there is an urgent need to reduce the incidence of these reproductive disorders, which can be addressed by correlative studies on early life exposure and adult reproductive dysfunction together with tools to assess the specific exposures and methods to block their effects. This review of the EDC literature as it relates to female health provides an important platform on which women's health can be improved.
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Yang CY, Wang YJ, Chen PC, Tsai SJ, Guo YL. Exposure to a mixture of polychlorinated biphenyls and polychlorinated dibenzofurans resulted in a prolonged time to pregnancy in women. ENVIRONMENTAL HEALTH PERSPECTIVES 2008; 116:599-604. [PMID: 18470317 PMCID: PMC2367681 DOI: 10.1289/ehp.10715] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Accepted: 01/22/2008] [Indexed: 05/04/2023]
Abstract
BACKGROUND Polychlorinated biphenyls (PCBs), dibenzofurans (PCDFs), and dibenzodioxins (PCDDs) may affect the female reproductive system in animals and humans. In 1978-1979, a mass poisoning occurred in central Taiwan due to PCB/PCDF-contaminated cooking oil; this incident was called Yucheng ("oil disease" in Chinese). OBJECTIVE The purpose of our study was to determine whether PCB/PCDF exposure affected fertility in exposed women. METHODS After the event, we followed the exposed individuals and a reference group who were sex-, age-, and community-matched. In 2003, we obtained fertility histories from Yucheng and reference women by telephone interview. We used Kaplan-Meier survival curves and multivariable Cox regression to compare time to pregnancy (TTP) between Yucheng and reference women, and we performed multiple logistic regression to determine whether PCB/PCDF exposure caused infertility. RESULTS In total, 412 women responded, with a median TTP of 4 months in Yucheng women and 3 months in reference women (p = 0.019). After adjusting for confounders by Cox regression, we found a fecundability ratio of 0.90 [95% confidence interval (CI), 0.80-1.00] for Yucheng women. Among the 408 women who had non-contraceptive sexual activity for > 12 months, 19.7% of Yucheng women and 9.7% of reference women did not become pregnant (i.e., they were infertile). After we adjusted for confounders by logistic regression, the infertility odds ratio was 2.34 (95% CI, 1.23-4.59) for Yucheng women compared with the reference group. CONCLUSIONS We found prolonged TTP and reduced fertility among women previously exposed to PCBs/PCDFs. Because of the limited sample size and the relatively small decrease in the fertility rate, these effects require cautious interpretation and further investigation for confirmation.
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Affiliation(s)
- Chiu-Yueh Yang
- The Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan, Taiwan
- Department of Health Business Administration, Hung-Kuang University, Taichung, Taiwan
| | - Ying-Jan Wang
- Department of Environmental and Occupational Health, National Cheng Kung University Medical College, Tainan, Taiwan
| | - Pau-Chung Chen
- Department of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei, Taiwan
| | - Shaw-Jenq Tsai
- The Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan, Taiwan
- Department of Physiology, National Cheng Kung University Medical College, Tainan, Taiwan
| | - Yueliang Leon Guo
- Department of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei, Taiwan
- Department of Environmental and Occupational Medicine, National Taiwan University (NTU) and NTU Hospital, Taipei, Taiwan
- Address correspondence to Y.L. Guo, Department of Environmental and Occupational Medicine, National Taiwan University (NTU) and NTU Hospital, 17, Syujhou Rd., Taipei 100, Taiwan, ROC. Telephone: 886-2-33228216. Fax: 886-2-33228214. E-mail:
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Cao Y, Winneke G, Wilhelm M, Wittsiepe J, Lemm F, Fürst P, Ranft U, Imöhl M, Kraft M, Oesch-Bartlomowicz B, Krämer U. Environmental exposure to dioxins and polychlorinated biphenyls reduce levels of gonadal hormones in newborns: Results from the Duisburg cohort study. Int J Hyg Environ Health 2008; 211:30-9. [PMID: 17660003 DOI: 10.1016/j.ijheh.2007.04.005] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Revised: 03/21/2007] [Accepted: 04/07/2007] [Indexed: 11/28/2022]
Abstract
BACKGROUND Endocrine dysfunction related to the hypothalamic-pituitary-thyroid (HPT) and/or the hypothalamic-pituitary-gonadal axis (HPG) is being discussed as underlying developmental adversity of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs). This study was done to evaluate effects related to the HPG axis. METHODS A birth-cohort study was initiated in the year 2000. Healthy mother-infant pairs were recruited in the industrialized city of Duisburg, Germany. Dioxins, dioxin-like PCBs and six indicator PCBs were measured in maternal blood during pregnancy and in maternal milk. Testosterone and estradiol levels were measured in maternal and cord serum of 104 mother-infant pairs representing a subsample with a complete data set of the total basic sample of 232 participants. Linear regression analysis was used to describe the association of PCDD/Fs or PCB in maternal blood or milk with sex steroid concentrations after adjustment for confounding. RESULTS Median concentrations for PCDD/Fs in maternal blood fat and milk fat in terms of WHO-TEq were 15.3 and 13.1pg WHO-TEq/g, respectively, and for the sum of the indicator PCBs (#28, #52, #101, #138, #153, #180) 149 and 177ng/g. The adjusted ratio of geometric means when doubling the concentration of PCDD/Fs in maternal blood fat was 0.86, 95% confidence interval (95% CI): 0.72-1.03 for testosterone and 0.73 (0.61-0.87) for estradiol in cord serum. Typically, testosterone reduction was more pronounced in cord serum of female and estradiol reduction in that of male babies. Reduction of hormone levels was generally more pronounced for dioxins than for indicator PCBs. CONCLUSIONS The hypothalamic-pituitary-gonadal axis of newborn babies is influenced by prenatal exposure to PCDD/Fs and PCBs in a manner suggestive of AhR-mediation. The clinical relevance of this finding remains to be established, however.
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Affiliation(s)
- Yuguang Cao
- Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
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Steinberg RM, Walker DM, Juenger TE, Woller MJ, Gore AC. Effects of perinatal polychlorinated biphenyls on adult female rat reproduction: development, reproductive physiology, and second generational effects. Biol Reprod 2008; 78:1091-101. [PMID: 18305224 DOI: 10.1095/biolreprod.107.067249] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Perinatal exposures to endocrine-disrupting chemicals, such as polychlorinated biphenyls (PCBs), can cause latent effects on reproductive function. Here, we tested whether PCBs administered during late pregnancy would compromise reproductive physiology in both the fetally exposed female offspring (F1 generation), as well as in their female offspring (F2 generation). Pregnant Sprague-Dawley rats were treated with the PCB mixture, Aroclor 1221 (A1221; 0, 0.1, 1, or 10 mg/kg), on Embryonic Days 16 and 18. Somatic and reproductive development of F1 and their F2 female offspring were monitored, including ages of eye opening, pubertal landmarks, and serum reproductive hormones. The results showed that low doses of A1221 given during this critical period of neuroendocrine development caused differential effects of A1221 on F1 and F2 female rats. In both generations, litter sex ratio was skewed toward females. In the F1 generation, additional effects were found, including a significant alteration of serum LH in the 1 mg/kg A1221 group. The F2 generation showed more profound alterations, particularly with respect to fluctuations in hormones and reproductive tract tissues across the estrous cycle. On proestrus, the day of the preovulatory GnRH/gonadotropin surge, F2 females whose mothers had been exposed perinatally to A1221 exhibited substantially suppressed LH and progesterone concentrations, and correspondingly smaller uterine and ovarian weights on estrus, compared with F2 descendants of control rats. These latter changes suggest a dysregulation of reproductive physiology. Thus, low levels of exposure to PCBs during late fetal development cause significant effects on the maturation and physiology of two generations of female offspring. These findings have implications for reproductive health and fertility of wildlife and humans.
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Affiliation(s)
- Rebecca M Steinberg
- The Institute for Neuroscience, The University of Texas at Austin, Austin, Texas 78712, USA
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Buck Louis GM, Gray LE, Marcus M, Ojeda SR, Pescovitz OH, Witchel SF, Sippell W, Abbott DH, Soto A, Tyl RW, Bourguignon JP, Skakkebaek NE, Swan SH, Golub MS, Wabitsch M, Toppari J, Euling SY. Environmental factors and puberty timing: expert panel research needs. Pediatrics 2008; 121 Suppl 3:S192-207. [PMID: 18245512 DOI: 10.1542/peds.1813e] [Citation(s) in RCA: 196] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Serono Symposia International convened an expert panel to review the impact of environmental influences on the regulation of pubertal onset and progression while identifying critical data gaps and future research priorities. An expert panel reviewed the literature on endocrine-disrupting chemicals, body size, and puberty. The panel concluded that available experimental animal and human data support a possible role of endocrine-disrupting chemicals and body size in relation to alterations in pubertal onset and progression in boys and girls. Critical data gaps prioritized for future research initiatives include (1) etiologic research that focus on environmentally relevant levels of endocrine-disrupting chemicals and body size in relation to normal puberty as well as its variants, (2) exposure assessment of relevant endocrine-disrupting chemicals during critical windows of human development, and (3) basic research to identify the primary signal(s) for the onset of gonadotropin-releasing hormone-dependent/central puberty and gonadotropin-releasing hormone-independent/peripheral puberty. Prospective studies of couples who are planning pregnancies or pregnant women are needed to capture the continuum of exposures at critical windows while assessing a spectrum of pubertal markers as outcomes. Coupled with comparative species studies, such research may provide insight regarding the causal ordering of events that underlie pubertal onset and progression and their role in the pathway of adult-onset disease.
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Affiliation(s)
- Germaine M Buck Louis
- Epidemiology Branch, Division of Epidemiology, Statistics and Prevention Research, National Institute of Child Health and Human Development, 6100 Executive Blvd, Room 7B03, Rockville, MD 20852, USA.
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Goldman JM, Murr AS, Cooper RL. The rodent estrous cycle: characterization of vaginal cytology and its utility in toxicological studies. ACTA ACUST UNITED AC 2007; 80:84-97. [PMID: 17342777 DOI: 10.1002/bdrb.20106] [Citation(s) in RCA: 514] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
While an evaluation of the estrous cycle in laboratory rodents can be a useful measure of the integrity of the hypothalamic-pituitary-ovarian reproductive axis, it can also serve as a way of insuring that animals exhibiting abnormal cycling patterns are disincluded from a study prior to exposure to a test compound. Assessment of vaginal cytology in regularly cycling animals also provides a means to establish a comparable endocrine milieu for animals at necropsy. The procedure for obtaining a vaginal smear is relatively non-invasive and is one to which animals can become readily accustomed. It requires few supplies, and with some experience the assessments can be easily performed in fresh, unstained smears, or in fixed, stained ones. When incorporated as an adjunct to other endpoint measures, a determination of a female's cycling status can contribute important information about the nature of a toxicant insult to the reproductive system. In doing so, it can help to integrate the data into a more comprehensive mechanistic portrait of the effect, and in terms of risk assessment, may provide some indication of a toxicant's impact on human reproductive physiology.
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Affiliation(s)
- Jerome M Goldman
- Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA.
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Chao HR, Wang SL, Lin LY, Lee WJ, Päpke O. Placental transfer of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in Taiwanese mothers in relation to menstrual cycle characteristics. Food Chem Toxicol 2006; 45:259-65. [PMID: 17029725 DOI: 10.1016/j.fct.2006.07.032] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2005] [Revised: 06/05/2006] [Accepted: 07/18/2006] [Indexed: 11/30/2022]
Abstract
The aim was to determine the body burden of dioxins and polychlorinated biphenyls (PCBs) and whether they are associated with variables influencing reproduction. Our subjects were healthy women (mean age of 29 [SD=4.5]) from central Taiwan. The congeners of dioxins and dioxin-like PCBs in placentas (n=119) were identified using gas chromatography/high resolution mass spectrometry. The median levels of polychlorinated dibenzo-p-dioxins/dibenzofurans and PCBs were 10.2 (geometric mean [GM]: 9.8, 95% confidence interval [95% CI]: 8.8-10.9) and 2.7 (GM: 2.7, 95% CI: 2.3-3.1) pg WHO-TEQ/g lipid, respectively. Total TEQ level in placentas was significantly correlated with mothers' arm circumference (r=0.22, p=0.043). Increased body fat percentage was associated with higher total TEQ level in placentas. After adjustment for maternal age, pre-pregnant body mass index (BMI), and parity, placental dioxin-TEQ level higher in women (age 19 years) with irregular menstrual cycle than in those (age <18 years) with regular menstrual cycle (p=0.032) and placental PCB-TEQ level was higher in women with menstrual cycles longer than 33 days versus less than 33 days (p=0.006). Thus, environmental exposure to dioxins and PCBs may be related to changes in current menstrual cycle characteristics.
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Affiliation(s)
- H-R Chao
- Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Neipu, Pingtung, Taiwan
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Ma R, Sassoon DA. PCBs exert an estrogenic effect through repression of the Wnt7a signaling pathway in the female reproductive tract. ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114:898-904. [PMID: 16759992 PMCID: PMC1480489 DOI: 10.1289/ehp.8748] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Polychlorinated biphenyls (PCBs) have been proposed to have a weak estrogenic activity and therefore pose a risk as potential environmental endocrine disruptors to the perinatal development of the female reproductive tract. Perinatal exposure to high concentrations of the potent synthetic estrogen diethylstilbestrol (DES) induces abnormal development of the female reproductive tract via a mechanism that acts through the down-regulation of Wnt7a (wingless-type MMTV integration site family, member 7A). To test the hypothesis that PCBs act as weak estrogens, we injected neonatal mice with a commercial PCB mixture (Aroclor 1254) or with low levels of DES and measured effects of exposure on Wnt7a expression and uterine morphology. We report here that neonatal PCB or low-level DES exposure resulted in the down-regulation of Wnt7a expression. In addition, both PCB and low-level DES exposure induced changes in the uterine myometrium and gland formation. These data reveal that weak estrogens such as the PCBs act through a Wnt7a-dependent pathway and suggest that Wnt7a regulation is a sensitive biomarker for testing weak estrogenic candidate compounds. The morphologic changes that were elicited by PCBs and DES were different immediately after exposure, suggesting that Wnt7a-independent pathways are also activated by one or both of these compounds. Although Wnt7a down-regulation is transient after estrogenic exposure, subsequent morphologic changes became more pronounced during postnatal and adult life, suggesting that the female reproductive tract is permanently reprogrammed after exposure even to weak estrogenic compounds. In addition, Wnt7a heterozygous mice were more sensitive to PCB exposure, revealing an important genetic predisposition to risks of environmental endocrine disruptors.
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Affiliation(s)
- Risheng Ma
- Brookdale Department of Molecular, Cell, and Developmental Biology, Mount Sinai Medical School, New York, New York, USA
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