RESUMO
BACKGROUND: Disinfection byproducts (DBPs) have been shown to impair thyroid function in experimental models. However, epidemiological evidence is scarce. METHODS: This study included 1190 women undergoing assisted reproductive technology (ART) treatment from the Tongji Reproductive and Environmental (TREE) cohort from December 2018 to August 2021. Serum thyrotropin (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were measured as indicators of thyroid function. FT4/FT3 and TSH/FT4 ratios were calculated as markers of thyroid hormone homeostasis. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), the two most abundant HAAs, in urine were detected to assess individual DBP exposures. RESULTS: After adjusting for relevant covariates, positive associations were observed between urinary TCAA concentrations and serum TSH and TSH/FT4 levels (e.g., percent change = 5.82 %, 95 % CI: 0.70 %, 11.21 % for TSH), whereas inverse associations were found for serum FT3 and FT4 (e.g., percent change = -1.29 %, 95 % CI: -2.49 %, -0.07 % for FT3). There also was a negative association between urinary DCAA concentration and serum FT4/FT3 (percent change = -2.49 %, 95 % CI: -4.71 %, -0.23 %). These associations were further confirmed in the restricted cubic spline and generalized additive models with linear or U-shaped dose-response relationships. CONCLUSION: Urinary HAAs were associated with altered thyroid hormone homeostasis among women undergoing ART treatment.
Assuntos
Glândula Tireoide , Humanos , Feminino , Adulto , Tiroxina/sangue , Tri-Iodotironina/sangue , Tireotropina/sangue , Hormônios Tireóideos/sangue , Testes de Função Tireóidea , Desinfetantes , Acetatos , ChinaRESUMO
Prenatal exposures to phthalates and bisphenols have been shown to be linked with adverse birth outcomes. Oxidative stress (OS) is considered a potential mechanism. The objective of this study was to explore the individual and mixtures of prenatal exposures to phthalates and bisphenols in associations with OS biomarkers. We measured eight phthalate metabolites and three bisphenols in the urine samples from 105 pregnant women in Wuhan, China. Urinary 8-hydroxydeoxyguanosine (8-OHdG), 8-isoprostaglandin F2α (8-isoPGF2α), and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA) were determined as OS biomarkers. The OS biomarkers in associations with the individual chemicals were estimated by linear regression models and restricted cubic spline (RCS) models, and their associations with the chemical mixtures were explored by quantile g-computation (qg-comp) models. In single-pollutant analyses, five phthalate metabolites including monomethyl phthalate (MMP), monoethyl phthalate (MEP), mono-(2-ethylhexyl) phthalate (MEHP), (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) were positively associated with urinary 8-OHdG levels (all FDR-adjusted P = 0.06). These associations were further confirmed by the RCS models and were linear (P for overall association ≤ 0.05 and P for non-linear association > 0.05). In mixture analyses, qg-comp models showed that a one-quartile increase in the chemical mixtures of phthalate metabolites and bisphenols was positively associated with urinary levels of 8-OHdG and 8-isoPGF2α, and bisphenol A (BPA) and bisphenol F (BPF) were the most contributing chemicals, respectively. Prenatal exposures to individual phthalates and mixtures of phthalates and bisphenols were associated with higher OS levels.
Assuntos
Compostos Benzidrílicos , Dietilexilftalato/análogos & derivados , Poluentes Ambientais , Fenóis , Ácidos Ftálicos , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Gravidez , Poluentes Ambientais/análise , Ácidos Ftálicos/metabolismo , Biomarcadores/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Estresse Oxidativo , Exposição Ambiental/análiseRESUMO
Importance: Numerous studies have documented the association of self-rated health (SRH) with chronic diseases. However, few studies have investigated its association with semen quality. Objective: To examine the association of SRH with semen quality among men undergoing assisted reproductive technology (ART) in China. Design, Setting, and Participants: This cross-sectional study recruited male partners in couples undergoing ART treatment at the Center for Reproductive Medicine, Tongji Hospital, Wuhan, China. A total of 1262 men underwent 2 semen examinations and completed a questionnaire on SRH between December 2018 and January 2020. Data analysis was performed from November 20, 2022, to March 24, 2023. Exposure: SRH, including overall physical and mental health, as well as reproductive-related physical and mental health specifically, were reported at baseline recruitment. Main Outcomes and Measures: Sperm concentration, sperm progressive motility, sperm motility, and sperm count as semen quality parameters. Results: The study included 1262 men with a mean (SD) age of 32.79 (5.25) years and body mass index of 24.37 (3.68). Men with poorer SRH had lower semen quality (eg, sperm concentration among poor vs very good overall physical health: percentage variation, -14.67%; 95% CI, -23.62% to -4.66%). Among 4 components of SRH, a greater reduction in semen quality was estimated for reproductive-related SRH compared with overall SRH, whereas the greatest reduction was observed for reproductive-related physical SRH. In comparison with men with very good reproductive-related physical SRH, men with poor reproductive-related physical SRH had differences of -24.78% (95% CI, -32.71% to -15.93%) and -25.61% (95% CI, -33.95% to -16.22%) in sperm count and concentration, respectively, and regression coefficients of -9.38 (95% CI, -12.01 to -6.76) and -9.24 (95% CI, -11.82 to -6.66) for sperm motility and sperm progressive motility, respectively. Conclusions and Relevance: In this cross-sectional study of Chinese men, poorer SRH was associated with lower semen quality, and reproductive-related physical SRH was the most pronounced indicator. Our findings suggest that SRH, especially reproductive-related physical SRH, was a good indicator of semen quality, which should inform public and clinical regulatory decisions.
Assuntos
Análise do Sêmen , Motilidade dos Espermatozoides , Masculino , Humanos , Adulto , Estudos Transversais , Sêmen , Técnicas de Reprodução AssistidaRESUMO
BACKGROUND: Experimental studies have shown that disinfection byproducts (DBPs) induce coagulotoxicity, but human evidence is scarce. OBJECTIVE: This study aimed to explore the relationships of DBP exposures with blood coagulation parameters. METHODS: Among 858 women from the Tongji Reproductive and Environmental (TREE) study, urinary dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were detected as internal biomarkers of DBP exposures. We measured activated partial thromboplastin time (APTT), fibrinogen (Fbg), international normalized ratio (INR), prothrombin time (PT), and thrombin time (TT) as blood coagulation parameters. Multivariable linear regression models were utilized to estimate the relationships between urinary DCAA and TCAA and blood coagulation parameters. The effect modifications by demographic and lifestyle characteristics were further explored. RESULTS: Elevated tertiles of urinary DCAA concentrations were associated with increased PT and INR (11.29%, 95% CI: 1.66%, 20.92% and 0.99%, 95% CI: 0.08%, 1.90% for the third vs. first tertile, respectively; both P for trends < 0.05). Stratification analysis showed that the positive associations were only observed among younger (< 30 years), leaner (body mass index < 24.0 kg/m2), and non-passive smoking women. Moreover, elevated tertiles of urinary TCAA concentrations in positive associations with PT and INR were observed among younger women (17.89%, 95% CI: 2.50%, 33.29% and 1.82%, 95% CI: 0.34%, 3.30% for the third vs. first tertile, respectively; both P for trends < 0.05) but not among older women (both P for interactions < 0.05). CONCLUSION: Higher levels of urinary DCAA and TCAA are associated with prolonged clotting time among women.
Assuntos
Desinfecção , Reprodução , Humanos , Feminino , Idoso , Desinfecção/métodos , Coagulação Sanguínea , Ácido Tricloroacético/urina , Biomarcadores/urina , Ácido Dicloroacético/urinaRESUMO
BACKGROUND: Experimental studies show that disinfection byproducts (DBPs) can inhibit oocyte maturation, decrease fertilization capacity, and impair embryo development, but human evidence is lacking. OBJECTIVES: We aimed to evaluate the associations between exposure to drinking water DBPs and in vitro fertilization (IVF) outcomes. METHODS: The study included 1,048 women undergoing assisted reproductive technology (ART) treatment between December 2018 and January 2020 from a prospective cohort study, the Tongji Reproductive and Environmental study in Wuhan, China. Exposure to DBPs was assessed by dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) in up to four urine samples, which were collected on the day of both enrollment and oocyte retrieval. Multivariable generalized linear mixed models, accounting for multiple IVF cycles per woman, were applied to evaluate the associations between urinary biomarkers of DBP exposures and IVF outcomes. Stratified analyses were used to explore the potential effect modifiers. RESULTS: The included 1,048 women underwent 1,136 IVF cycles, with 960 (91.6%), 84 (8.0%), and 4 (0.4%) women contributing one cycle, two cycles, and three cycles, respectively. We found that elevated quartiles of urinary DCAA and TCAA concentrations were associated with reduced numbers of total oocytes and metaphase II oocytes and that urinary DCAA concentrations with a lower proportion of best-quality embryos (all p for trends<0.05). Moreover, elevated quartiles of urinary DCAA concentrations were associated with decreased proportions of successful implantation, clinical pregnancy, and live birth (14%, 15%, and 15% decreases in adjusted means comparing the extreme quartiles, respectively; all p for trends<0.05). Stratification analyses showed that the inverse associations of urinary TCAA concentrations with multiple IVF outcomes were stronger among women ≥30 y of age (p for interactions<0.05). DISCUSSION: Exposure to drinking water DBPs was inversely associated with some IVF outcomes among women undergoing ART treatment. Further study is necessary to confirm our findings. https://doi.org/10.1289/EHP12447.
Assuntos
Desinfecção , Água Potável , Gravidez , Humanos , Feminino , Masculino , Estudos Prospectivos , Fertilização in vitro , China , Ácido DicloroacéticoRESUMO
Phthalates are widespread endocrine disrupting chemicals that adversely affect female reproductive health. We aimed to investigate the individual and joint associations of phthalate exposures measured by repeated urinary metabolites with polycystic ovary (PCO) and polycystic ovary syndrome (PCOS) (96 PCO cases, 96 PCOS cases and 370 controls). In single-pollutant analyses, mono-isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP) and the sum of di(2-ethylhexyl) phthalate (∑DEHP) were associated with increased prevalence of PCO. Mono(2-ethylhexyl) phthalate (MEHP), MBzP and ∑DEHP were associated with elevated prevalence of PCOS. In multiple-pollutant analyses, one-quartile increase of weighted quantile sum index in phthalate metabolite mixtures was associated with increased prevalence of PCO and PCOS, and MBzP was the most major contributor. Our findings suggest a potential role for phthalate exposures, both individually and in mixtures, in the development of PCO and PCOS.
Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Síndrome do Ovário Policístico , Feminino , Humanos , Síndrome do Ovário Policístico/induzido quimicamente , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/urina , Poluentes Ambientais/toxicidade , Poluentes Ambientais/urina , Exposição AmbientalRESUMO
BACKGROUND: Epidemiological studies on phthalate exposures in associations with uterine fibroids (UF) and endometriosis (EMT) are inconsistent. The underlying mechanisms are poorly understood. OBJECTIVES: To investigate the relationships of urinary phthalate metabolites with UF and EMT risks, and further to examine the mediating role of oxidative stress. METHODS: This study included 83 and 47 women separately diagnosed with UF and EMT, as well as 226 controls from the Tongji Reproductive and Environmental (TREE) cohort. Two spot urine samples from each woman were analyzed for two oxidative stress indicators and eight urinary phthalate metabolites. Unconditional logistic regression models or multivariate regression models were fitted to evaluate the associations among phthalate exposures, oxidative stress indicators, and the risks of UF and EMT. The potential mediating role of oxidative stress was estimated by the mediation analyses. RESULTS: We observed that each ln-unit increase in urinary mono-benzyl phthalate (MBzP) concentrations was associated with increased UF risk [adjusted OR (aOR): 1.56, 95% CI: 1.20, 2.02], and that each ln-unit increase in urinary MBzP (aOR: 1.48, 95% CI: 1.09, 1.99), mono-isobutyl phthalate (MiBP) (aOR: 1.83, 95% CI: 1.19, 2.82), and mono-2-ethylhexyl phthalate (MEHP) (aOR: 1.66, 95% CI: 1.19, 2.31) concentrations were associated with increased EMT risk (all FDR-adjusted P < 0.05). Moreover, we observed that all tested urinary phthalate metabolites were positively associated with two oxidative stress indicators [4-hydroxy-2-nonenal-mercapturic acid (4-HNE-MA) and 8-hydroxy-2-deoxyguanosine (8-OHdG)], in which 8-OHdG was associated with increased risks of UF and EMT (all FDR-adjusted P < 0.05). The mediation analyses showed that 8-OHdG mediated the positive relationships of MBzP with UF risk, and of MiBP, MBzP, and MEHP with EMT risk, with the estimated intermediary proportion ranging from 32.7% to 48.1%. CONCLUSIONS: Oxidatively generated DNA damage may mediate the positive associations of certain phthalate exposures with the risks of UF and EMT. However, further investigation is warranted to confirm these findings.
Assuntos
Endometriose , Poluentes Ambientais , Leiomioma , Ácidos Ftálicos , Humanos , Feminino , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/urina , 8-Hidroxi-2'-Desoxiguanosina , Leiomioma/induzido quimicamente , Leiomioma/genética , Dano ao DNA , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidadeRESUMO
BACKGROUND: Parabens, as suspected endocrine disruptors, are widely used in personal care products and pharmaceuticals. However, variability, predictors, and risk assessments of human exposure to parabens are not well characterized. OBJECTIVE: To evaluate within-day variability, predictors, and risk assessments of exposure to parabens among Chinese adult men. METHODS: We measured four parabens including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP) in repeated urine samples from 850 Chinese adult men. We examined the variability by intraclass correlation coefficients (ICCs) and identified the predictors by multivariable linear mixed models. We assessed risks of paraben exposures based on the estimated daily intake (EDI). RESULTS: The four parabens were detected in >76% of urinary samples. We observed fair to good to high reproducibility (ICCs: 0.71 to 0.86) for urinary paraben concentrations within one day. Use of facial cleanser was associated with higher four urinary paraben concentrations. Increasing age, taking medicine, intravenous injection, and interior decoration in the workplace were related to higher urinary concentrations of specific parabens. Smoking and drinking were associated with lower urinary concentrations of specific parabens. The maximum EDIs for the four parabens ranged from 13.76 to 848.68 µg/kg bw/day, and 0.9% of participants had the hazard quotient values > 1 driven by PrP exposure. CONCLUSIONS: Urinary paraben concentrations were less variable within one day. Several lifestyle characteristics including use of facial cleanser and pharmaceuticals may contribute to paraben exposures.
Assuntos
Exposição Ambiental , Parabenos , Masculino , Humanos , Adulto , Parabenos/análise , Exposição Ambiental/análise , População do Leste Asiático , Reprodutibilidade dos Testes , Medição de Risco , Preparações FarmacêuticasRESUMO
Phthalates, as endocrine disrupting chemicals that can alter the endogenous hormones, may be involved in the incidence of endometrial polyp, a benign hormone-dependent condition. We conducted a pilot case-control study from the Tongji Reproductive and Environmental (TREE) cohort to investigate the associations between phthalate exposures and the risk of endometrial polyp. A total of 40 endometrial polyp patients were matched to 80 controls by age and body mass index in the ratio of 1:2. Two spot urine samples from each subject were quantified for eight phthalate metabolites to enhance exposure assessment. The conditional logistic regression and quantile-based g-computation models were separately used to explore the associations between individual and mixture of urinary phthalate metabolites and the risk of endometrial polyp. After adjusting for covariates, individual chemical analyses showed that urinary monobenzyl phthalate (MBzP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono(2-ethylhexyl) phthalate (MEHHP) and the sum of di(2-ethylhexyl) phthalate (ΣDEHP) were associated with increased risks of endometrial polyp, with adjusted odds ratios ranging from 2.62 (95% CI: 0.88, 7.84) for MECPP to 6.96 (95% CI: 1.87, 25.87) for ΣDEHP comparing the extreme exposure categories (all P for trends <0.05 or = 0.057). These associations still persisted when these exposures were modeled as continuous variables. Chemical mixture analyses showed that a simultaneous one-quartile increase in concentrations of eight phthalate metabolites was associated with an elevated odds ratio of 3.14 (95% CI: 1.49, 6.60) in endometrial polyp. Our data suggests that exposure to individual benzylbutyl phthalate (BBzP) and DEHP, as well as mixture of phthalates is associated with increased risk of endometrial polyp. This may inform public health recommendations and policies to avoid phthalate exposures for improving female reproductive health.
Assuntos
Dietilexilftalato , Poluentes Ambientais , Ácidos Ftálicos , Feminino , Humanos , Poluentes Ambientais/urina , Projetos Piloto , Estudos de Casos e Controles , Ácidos Ftálicos/toxicidade , Reprodução , Exposição Ambiental/análiseRESUMO
BACKGROUND: Bisphenol A (BPA) as an endocrine disrupting chemical has been shown to alter reproductive endocrine function, but little is known on its analogues such as bisphenol F (BPF) and bisphenol S (BPS) with increasing usage and exposure. OBJECTIVE: To explore the associations between exposures to BPA, BPF and BPS and serum reproductive hormones among reproductive-aged Chinese men. METHODS: We measured BPA, BPF and BPS concentrations in repeated urine samples and multiple reproductive hormones in the serum samples collected from 462 men attending an infertility clinic in Wuhan, China. Linear regression models were applied to assess the associations between averaged urinary BPA, BPF and BPS levels and serum hormone concentrations, and restricted cubic spline (RCS) models were further utilized to explore potential non-linear associations. We also examined potential modifying effects by age and body mass index (BMI). RESULTS: There was little evidence of associations between BPA exposure and altered reproductive hormones. However, we found that elevated BPF and BPS exposures were in negative associations with estrogen (E2) levels and E2/T (total testosterone) ratio (all P for trends < 0.05), and that elevated BPS exposure was negatively associated with SHBG levels (P for trend = 0.09). Based on the RCS models, these linear negative associations except that between BPS exposure and E2/T ratio were further confirmed. In stratified analyses, BPF and BPS exposures in relation to reduced E2 and E2/T ratio were more pronounced among men aged > 30 years, whereas their associations with reduced SHBG levels were more pronounced among men aged ≤ 30. Also, BPS exposure in negative association with FSH only emerged among men with BMI ≥ 24 kg/m2 (P for interaction = 0.03). CONCLUSION: BPF and BPS exposures were negatively associated with male serum E2, E2/T ratio and SHBG levels, and these associations varied by age and BMI.
Assuntos
Compostos Benzidrílicos , Disruptores Endócrinos , Adulto , Compostos Benzidrílicos/urina , China , Disruptores Endócrinos/efeitos adversos , Humanos , Masculino , Fenóis , Reprodução , TestosteronaRESUMO
Previous studies have reported that exposure to phthalates and polycyclic aromatic hydrocarbons (PAHs) is individually associated with altered semen quality, but no human studies have evaluated their joint effects of exposure mixtures, a more real-world scenario. We aimed to explore urinary metabolite mixtures of phthalates and PAHs in associations with semen quality. Repeated spot-urine samples gathered from 695 men attending a fertility clinic were analyzed for urinary metabolites of eight phthalates and ten monohydroxylated-PAHs (OH-PAHs). Principal component analysis (PCA)-multivariable linear regression (MLR) model, quantile g-computation (qg-comp), and Bayesian kernel machine regression (BKMR) were applied to estimate the associations of urinary mixtures of phthalate and OH-PAH metabolites with semen quality. The overall effects of urinary mixtures of phthalate and PAH metabolites on semen quality were not statistically significant. However, hydroxynaphthalene (OHNa) factor identified from PCA was monotonically associated with decreased total sperm count and sperm concentration, whereas di(2-ethylhexyl) phthalate (DEHP) factor was non-monotonically related to increased progressive sperm motility and total sperm motility. Qg-comp and BKMR models confirmed these findings and identified 2-OHNa and 2-OHFlu as the primary negative contributors, whereas MEOHP and MEHP as the primary positive contributors. Our findings suggest that exposure to mixtures of naphthalene and DEHP is associated with altered semen quality. The finding is warranted to confirm in further well-designed epidemiological studies.
Assuntos
Dietilexilftalato , Ácidos Ftálicos , Hidrocarbonetos Policíclicos Aromáticos , Masculino , Humanos , Análise do Sêmen , Hidrocarbonetos Policíclicos Aromáticos/análise , Clínicas de Fertilização , Motilidade dos Espermatozoides , Dietilexilftalato/metabolismo , Teorema de Bayes , Naftóis/análise , Sêmen/metabolismo , Ácidos Ftálicos/urina , Exposição Ambiental/análiseRESUMO
Phenols have been shown to influence the cellular proliferation and function of thyroid in experimental models. However, few human studies have investigated the association between phenol exposure and thyroid cancer, and the underlying mechanisms are also poorly understood. We conducted a case-control study by age- and sex-matching 143 thyroid cancer and 224 controls to investigate the associations between phenol exposures and the risk of thyroid cancer, and further to explore the mediating role of oxidative stress. We found that elevated urinary triclosan (TCS), bisphenol A (BPA) and bisphenol S (BPS) levels were associated with increased risk of thyroid cancer (all P for trends < 0.05), and the adjusted odds ratios (ORs) comparing the extreme exposure groups were 3.52 (95% confidence interval (CI): 2.08, 5.95), 2.06 (95% CI: 1.06, 3.97) and 7.15 (95% CI: 3.12, 16.40), respectively. Positive associations were also observed between urinary TCS, BPA and BPS and three oxidative stress biomarkers measured by 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-iso-prostaglandin F2α (8-isoPGF2α) and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), as well as between urinary 8-isoPGF2α and HNE-MA and the risk of thyroid cancer. Mediation analysis showed that urinary 8-isoPGF2α mediated 28.95%, 47.06% and 31.08% of the associations between TCS, BPA and BPS exposures and the risk of thyroid cancer, respectively (all P < 0.05). Our results suggest that exposure to TCS, BPA and BPS may be associated with increased risk of thyroid cancer and lipid peroxidation may be an intermediate mechanism. Further studies are warranted to confirm the findings.
Assuntos
Neoplasias da Glândula Tireoide , Triclosan , 8-Hidroxi-2'-Desoxiguanosina , Biomarcadores , Estudos de Casos e Controles , Humanos , Estresse Oxidativo , Fenol , Fenóis/toxicidade , Neoplasias da Glândula Tireoide/induzido quimicamente , Triclosan/toxicidadeRESUMO
BACKGROUND: Organochlorine pesticides (OCPs) are endocrine-disrupting chemicals and may alter male reproductive hormone concentrations. OBJECTIVE: To explore the associations between multiple OCP exposures and serum testosterone concentrations among Chinese men. METHODS: We investigated 421 men who provided serum samples from an infertility clinic in Wuhan, China. Each man completed a questionnaire concerning demographic characteristics and lifestyle habits. Serum concentrations of 18 OCPs and total testosterone were measured. Linear regression models were used to explore whether serum OCP levels were associated with altered testosterone concentrations, and potential effect modifications by age and body mass index (BMI) were also examined. RESULTS: After adjusting for potential confounders, elevated dieldrin and p,p'-DDD levels had monotonically negative and positive exposure-response associations with testosterone concentrations, respectively (-30.98 ng/dL, 95% CI: -72.34, 10.37; P for trend = 0.12 and 41.31 ng/dL, 95% CI: -0.32, 82.93; P for trend = 0.06 for the highest vs. non-detectable exposure category, respectively). After stratification by age and BMI, dieldrin in relation to decreased testosterone concentrations was more pronounced among men aged <30 years old, and p,p'-DDD in relation to increased testosterone concentrations was stronger among men aged ≥30 years old and among men with a BMI <24 kg/m2, though the differences were not statistically significant. CONCLUSION: The study found evidence that serum dieldrin and p,p'-DDD concentrations might be associated with altered serum testosterone concentrations.
Assuntos
Hidrocarbonetos Clorados , Praguicidas , Adulto , China , Dieldrin , Clínicas de Fertilização , Humanos , Hidrocarbonetos Clorados/análise , Masculino , Praguicidas/análise , TestosteronaRESUMO
BACKGROUND: Disinfection by-products (DBPs) have been shown to impair female reproductive function. However, epidemiological evidence on reproductive hormones is scarce. OBJECTIVE: To investigate the associations between DBP exposures and reproductive hormones among women undergoing assisted reproductive technology. METHODS: We included 725 women from the Tongji Reproductive and Environmental (TREE) Study, an ongoing cohort conducted in Wuhan, China during December 2018 and January 2020. Urine samples collected at recruitment were quantified for dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) as biomarkers of DBP exposures. At day 2-5 of menstruation, serum reproductive hormones including luteinizing hormone (LH), estradiol (E2), total testosterone (T), progesterone (PRGE), and prolactin (PRL) were determined. Multivariate linear regression models were performed to assess the associations of urinary DCAA and TCAA concentrations with reproductive hormone levels. Dose-response relationships were investigated using natural cubic spline (NCS) and restricted cubic spline (RCS) models. RESULTS: After adjusting for relevant confounders, we observed that higher urinary DCAA levels were associated with increased serum PRGE (9.2%; 95% CI: -0.55%, 19.8% for the highest vs. lowest tertile; P for trend = 0.06). Based on NCS models, we observed U-shaped associations of urinary DCAA with serum PRGE and PRL; each ln-unit increment in urinary DCAA concentrations above 3.61 µg/L and 6.30 µg/L was associated with 18.9% (95% CI: 4.8%, 34.7%) and 23.3% (95% CI: -0.92%, 53.5%) increase in serum PRGE and PRL, respectively. The U-shaped associations were further confirmed in RCS models (P for overall association ≤0.01 and P for non-linear associations ≤0.04). We did not observe evidence of associations between urinary TCAA and reproductive hormones. CONCLUSION: Urinary DCAA but not TCAA was associated with altered serum PRGE and PRL levels among women undergoing assisted reproductive technology.
Assuntos
Desinfecção , Ácido Tricloroacético , Biomarcadores/urina , Ácido Dicloroacético/urina , Feminino , Hormônios , Humanos , Ácido Tricloroacético/urinaRESUMO
Human studies on association between bisphenol A (BPA) exposure and semen quality, mostly based on single urinary measurement, are inconsistent. There is limited human evidence on BPA analogues such as bisphenol F (BPF) and bisphenol S (BPS), and little is known on potential effects of bisphenol mixtures. We aimed to explore whether individual or mixtures of BPA, BPS and BPF assessed in repeated urinary measurements were associated with semen quality among 984 Chinese men from an infertility clinic. We found that higher BPA exposure was associated with increased odds ratios (ORs) of having below-reference sperm concentration, total sperm count, progressive motility and total motility (all P for trends < 0.05). Higher BPS exposure was associated with increased ORs of having below-reference progressive motility and total motility (both P for trends = 0.02); the ORs comparing extreme quartiles were 1.62 (95% CI: 1.07, 2.43) and 1.57 (95% CI: 1.06, 2.33), respectively. Elevated risks for each outcome were also observed when bisphenol mixtures were at ≥ 55th percentiles. For semen quality parameters modeled as continuous outcomes, inverse associations with individual BPA and BPS and bisphenol mixtures were still estimated. Our results suggested that higher exposure to individual BPA and BPS and bisphenol mixtures were associated with impaired semen quality.
Assuntos
Clínicas de Fertilização , Análise do Sêmen , Compostos Benzidrílicos/efeitos adversos , China , Estudos Transversais , Humanos , Masculino , FenóisRESUMO
Disinfection byproducts (DBPs) have been shown to alter ovarian steroidogenesis and cause estrous cyclicity disturbance and prolongation in experimental studies, however human studies are lacking. We aimed to evaluate the cross-sectional associations between drinking water DBPs and menstrual cycle characteristics. A total of 1078 women attending an infertility clinic in Wuhan, China were included between December 2018 and January 2020. Characteristics of menstrual cycle were collected by questionnaires. Concentrations of dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were measured in urine as biomarkers of drinking water DBPs. Multivariate logistic and linear regression models were used to evaluate the associations between urinary DCAA and TCAA concentrations and menstrual cycle characteristics. Higher urinary DCAA concentrations were associated with increased odds ratios (ORs) of irregular menstrual cycle (OR = 1.80; 95% CI: 0.97, 3.33 for the highest vs. lowest quartile; P for trend = 0.05) and long menstrual cycle (OR = 1.62; 95% CI: 0.97, 2.70 for the highest vs. lowest quartile; P for trend = 0.06), as well as prolonged variation in cycle length (ß = 1.27 days; 95% CI: -0.11, 2.66 for the highest vs. lowest quartile; P for trend = 0.04). Higher urinary TCAA concentrations were associated with prolonged bleeding duration (ß = 0.23 days; 95% CI: -0.06, 0.51 for the highest vs. lowest quartile; P for trend = 0.07). These results suggest that exposure to drinking water DBPs is associated with menstrual cycle disturbances. These findings are warranted to confirm in other studies.
Assuntos
Desinfetantes , Água Potável , Estudos Transversais , Desinfecção/métodos , Feminino , Clínicas de Fertilização , Humanos , Ciclo MenstrualRESUMO
BACKGROUND: Prenatal exposure to metals has been linked with adverse pregnancy outcomes. Oxidative stress and epigenetic changes are potential mechanisms of action. OBJECTIVES: We aimed to examine the associations of individual and mixtures of metal exposures with oxidative stress and DNA methylation among pregnant women. METHODS: We measured a panel of 16 metals and 3 oxidative stress biomarkers including 8-hydroxydeoxyguanosine (8-OHdG), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA) and 8-isoprostaglandin F2α (8-isoPGF2α) in urine from 113 pregnant women in a Chinese cohort. Biomarkers of global DNA methylation including Alu and long interspersed nucleotide element-1 (LINE-1) in cord blood were measured. Multivariable linear regression and Bayesian kernel machine regression (BKMR) models were separately applied to estimate the associations between individual and mixtures of metal exposures and biomarkers of oxidative stress and global DNA methylation. RESULTS: In single-metal analyses, we observed positive associations between 11 metals [arsenic (As), cadmium (Cd), thallium (Tl), barium (Ba), nickel (Ni), vanadium (V), cobalt (Co), zinc (Zn), copper (Cu), selenium (Se) and molybdenum (Mo)] and at least one of oxidative stress biomarkers (all FDR-adjusted P-values < 0.05). In mixture analyses, we found positive overall associations of metal mixtures with 8-OHdG and 8-isoPGF2α, and Se was the most important predictor. There was no evidence on associations of urinary metals as individual chemicals and mixtures with Alu and LINE-1 methylation. CONCLUSION: Urinary metals as individual chemicals and mixtures were associated with increased oxidative stress, especially Se.
Assuntos
Metilação de DNA , Gestantes , Teorema de Bayes , Biomarcadores/urina , Feminino , Humanos , Estresse Oxidativo , GravidezRESUMO
BACKGROUND: Exposure to air pollution has been linked with altered immune function in adults, but little is known about its effects on early life. This study aimed to investigate the effects of exposure to air pollution during prenatal and postnatal windows on cell-mediated immune function in preschoolers. METHODS: Pre-school aged children (2.9 ± 0.5 y old, n = 391) were recruited from a mother-child cohort study in Wuhan, China. We used a spatial-temporal land use regression (LUR) model to estimate exposures of particulate matter with aerodynamic diameters ≤2.5 µm (PM2.5) and ≤10 µm (PM10), and nitrogen dioxide (NO2) during the specific trimesters of pregnancy and the first two postnatal years. We measured peripheral blood T lymphocyte subsets and plasma cytokines as indicators of cellular immune function. We used multiple informant models to examine the associations of prenatal and postnatal exposures to air pollution with cell-mediated immune function. RESULTS: Prenatal exposures to PM2.5, PM10, and NO2 during early pregnancy were negatively associated with %CD3+ and %CD3+CD8+ cells, and during late pregnancy were positively associated with %CD3+ cells. Postnatal exposures to these air pollutants during 1-y or 2-y childhood were positively associated with IL-4, IL-5, IL-6, and TNF-α. We also observed that the associations of prenatal or postnatal air pollution exposures with cellular immune responses varied by child's sex. CONCLUSIONS: Our results suggest that exposure to air pollution during different critical windows of early life may differentially alter cellular immune responses, and these effects appear to be sex-specific.
Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Criança , Pré-Escolar , Estudos de Coortes , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Humanos , Imunidade Celular , Masculino , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/toxicidade , Material Particulado/análise , Material Particulado/toxicidade , GravidezRESUMO
Studies indicate that phthalates can disrupt spermatogenesis and lead to the reduction of semen quality. However, the underlying mechanisms remain unclear. This study aimed to examine the associations of phthalate exposures as individual chemicals and mixtures with spermatogenesis-related miRNA106a. We detected eight phthalate metabolites in repeated urine samples and a single seminal plasma specimen among 111 men from an infertility clinic in Wuhan, China. Spermatogenesis-related miRNA106a was measured in seminal plasma. We used multivariable linear regression and Bayesian kernel machine regression (BKMR) models to separately evaluate the associations of phthalate metabolites as individual chemicals and mixtures with spermatogenesis-related miRNA106a. Elevated tertiles of urinary mono (2-ethylhexyl) phthalate (MEHP) was associated with decreased miRNA106a (-61.71%; 95%CI: 81.92, -18.93% for the highest vs. lowest tertile; P for trend = 0.01). Similarly, an inverse exposure-response relationship between seminal plasma MEHP concentrations and miRNA106a was also observed (-59.44%; 95%CI: 79.19, -20.95% for the highest vs. lowest tertile; P for trend = 0.01). The BKMR models showed that the mixtures of seminal plasma phthalate metabolites were associated with decreased miRNA106a when the chemical mixtures were ≥35th percentile compared to their medians. Nonlinear associations with miRNA106a were estimated for urinary and seminal plasma MEHP while fixing other phthalate metabolites at their medians. Our findings suggest that mixtures of phthalate metabolites in seminal plasma were negatively associated with spermatogenesis-related miRNA106a, and individual MEHP was the major contributor to the adverse effects.