Search Results (122)

Polystyrene microplastics (PS-MPs) released in the environment reportedly affect the reproduction of various organisms, induced oxidative stress and apoptosis, resulting in altered sperm parameters. In this in vitro study, we tested the cytotoxicity and genotoxicity of PS-MPs by exposing human semen samples to PS-MPs levels (105 and 210 μg/mL) for 30–60–90 min. Semen parameters, genome stability, sperm DNA fragmentation (SDF) and reactive oxygen species (ROS) production were analyzed before and after exposure. Moreover, we also evaluated the expression level of spermatozoa-specific expressed genes essential for the fusion with oocyte (DCST1, DCST2, IZUMO1, SPACA6, SOF1, and TMEM95). After PS-MP exposure, semen concentration and morphology did not differ, while sperm vitality and motility decreased in a time-dependent manner. In addition, sperm agglutination was observed in the groups exposed to both PS-MPs concentrations tested. A time- and concentration-dependent reduction in genomic stability, as well as increased SDF and ROS production, was also observed. Moreover, all investigated transcripts were down-regulated after PS-MP exposure. Our results confirm the oxidative stress-mediated genotoxicity and cytotoxicity of PS-MPs on human spermatozoa. The sperm agglutination observed after treatment could be due to the aggregation of PS-MPs already adhered to the sperm membranes, hindering sperm movement and fertilizing capability. Interestingly, the downregulation of genes required for sperm–oocyte fusion, resulting from data on the in vitro experimental system, suggests that PS-MP exposure may have implications for sperm functionality. While these findings highlight potential mechanisms of sperm dysfunction, further investigations using in vivo models are needed to determine their broader biological implications. Possible environmental and working exposure to pollutants should be considered during the counselling for male infertility. Full article

In recent decades, exposure to electromagnetic fields (EMFs) generated by standard devices has raised concerns about possible effects on reproductive health. This cross-sectional observational study examined the impact of EMFs on sperm motility in a sample of 102 healthy males aged 20–35 years in the IVF laboratory. Semen samples were exposed to different sources of EMF for one hour, and motility was assessed immediately thereafter. The results showed a significant reduction in progressive sperm motility after exposure to EMFs generated by mobile phones and Wi-Fi repeaters in the laboratory. In contrast, other equipment showed no significant effects. The study demonstrated a statistically significant reduction in progressive sperm motility following in vitro exposure to electromagnetic fields (EMFs) emitted by mobile communication devices and wireless local area network access points. Conversely, other electromagnetic emitting devices evaluated did not elicit significant alterations in this parameter. These findings suggest a potential negative impact of specific EMF sources on semen quality, underscoring the necessity for further comprehensive research to elucidate the clinical implications and to develop potential mitigation strategies aimed at reducing risks to male reproductive health. This study discourages the introduction of mobile phones in IVF laboratories and recommends positioning Wi-Fi repeaters on the ceiling. Full article

Bisphenol A (BPA) is a widespread environmental endocrine disruptor with significant neurodevelopmental and behavioral risks. The present study explored the role of the circadian clock protein NR1D1 in mediating BPA-induced anxiety-like behavior and brain inflammation early in life. Zebrafish embryos exposed to BPA exhibited anxiety-like behavior characterized by altered motor activity patterns. Notably, BPA exposure suppressed the expression of the circadian clock gene nr1d1, accompanied by increased transcriptional and protein levels of pro-inflammatory cytokines, including IL-6, IL-1β, and TNF-α. These changes created a pro-inflammatory microenvironment that disrupted dopamine system homeostasis, contributing to the observed behavioral abnormalities. Activation of NR1D1 using GSK effectively reversed BPA-induced inflammatory responses and restored normal dopamine levels and behavioral phenotypes. These findings highlight NR1D1 as a critical regulator linking circadian rhythm disruption, neuroinflammation, and dopaminergic dysfunction to anxiety-like behavior. This study provides novel insights into the mechanisms underlying BPA-induced neurotoxicity and identifies NR1D1 as a potential therapeutic target for mitigating the adverse effects of early-life BPA exposure. Full article

Evidence highlights the association between endocrine-disrupting chemicals (EDCs) found in personal care and household products (PCHPs) and adverse reproductive and developmental health outcomes. Women are disproportionately at risk due to frequent use of PCHPs, encountering a variety of different chemicals daily. Despite known health risks, existing policies often fail to provide adequate protection, with gaps remaining in understanding women’s knowledge, risk perceptions, and beliefs about EDCSs in PCHP, as well as how these influence avoidance behaviours. This study examines women’s knowledge, health risk perceptions, beliefs, and avoidance behaviors regarding EDCs commonly found in PCHPs, including bisphenol A, lead, parabens, phthalates, perchloroethylene, and triclosan. Guided by the Health Belief Model, a questionnaire was administered to 200 women in the preconception and conception periods in Toronto, Canada. Analyses revealed that lead and parabens were the most recognized EDCs, while triclosan and perchloroethylene were the least known. Greater knowledge of lead, parabens, bisphenol A, and phthalates significantly predicted chemical avoidance in PCHPs. Higher risk perceptions of parabens and phthalates also predicted greater avoidance. Women with higher education and chemical sensitivities were more likely to avoid lead. These findings support the need for targeted education to improve awareness to reduce EDC exposure—especially among women. Full article

The protective potentials of Tribulus terrestris (TT) and L-arginine (L-Arg) against reproductive toxicity induced by fipronil (FPN) in male rats were investigated. A total of 36 male rats were allocated into six groups: control, TT, L-Arg, FPN, FPN + TT, and FPN + L-Arg groups. The body and sex organ weights, semen criteria, serum testosterone levels, and testicular oxidative stress were determined. Sexual behavior, testicular and penile androgen receptor (AR), penile nitric oxide synthase (NOS), immunohistochemistry of proliferating cell nuclear antigen (PCNA), and histopathology were also assessed. FPN disrupted reproductive health by influencing the expression and activity of NOS and AR, leading to compromised erectile function, sexual dysfunction, and hormonal imbalance. Significant improvements in body weight, reproductive organ weights, the expression of NOS and AR, and testosterone levels were observed in the TT- and L-Arg-treated groups. Behavioral assessments indicated improved sexual performance in the TT- and L-Arg-treated groups. Histopathological studies of the testes and penis tissue, immunohistochemical expression of PCNA in testicular tissues, and biochemical analyses further confirmed the protective effects of TT and L-Arg. Collectively, these findings highlighted the potential of TT and L-Arg in counteracting FPN-induced reproductive impairments. Full article

(1) Background: This study aimed to detect whether alpha-lipoic acid (ALA) supplementation could reduce lead (Pb)-induced testicular toxicity in roosters. (2) Methods: A total of 48 roosters, aged 20 weeks, were selected and randomly allocated to six treatment groups: basic diet (CON); CON + 150 mg/kg (CH₃OO)₂Pb (LPB); CON + 300 mg/kg (CH₃OO)₂Pb (HPB); CON + 300 mg/kg ALA (ALA); LPB + 300 mg/kg ALA (ALP); and HPB + 300 mg/kg ALA (AHP). (3) Results: The testicular Pb content was obviously higher in the LPB and HPB groups than in the CON group, while ALA supplementation reduced the testicular Pb content (p < 0.05). Roosters showed a significant increase in serum testosterone, sperm viability, sperm concentration, and testicular score in the AHP group compared with the HPB group. Pb exposure caused a remarkable increase in sperm abnormality and testicular malondialdehyde level, which were down-regulated by ALA supplementation (p < 0.05). RNA sequencing identified 227 differentially expressed genes (DEGs) between the HPB and CON groups and 220 DEGs between the HPB and AHP groups. (4) Conclusions: ALA supplementation mitigated Pb-induced testicular damage, suggesting its potential as a therapeutic agent for Pb toxicity in birds and potentially other species. Full article

Air pollution exposure has been increasingly linked to adverse pregnancy outcomes. This study aimed to investigate the effects of PM_2.5 exposure throughout pregnancy on preterm birth, low birth weight (LBW), and small for gestational age (SGA). We analyzed a cohort of 16,965 pregnant women living in northern Thailand between 2016 and 2022. PM_2.5 concentration data were collected from two air quality monitoring stations operated by the Pollution Control Department (PCD) of Thailand. Logistic regression models were used to assess the association between daily PM_2.5 exposure and pregnancy outcomes. PM_2.5 exposure at levels exceeding 37.5 μg/m³ throughout pregnancy significantly increased the risk of preterm birth (aOR = 2.19, p < 0.001) and LBW (aOR = 1.99, p < 0.001) compared to the reference group (15.1–37.5 μg/m³). However, exposure at levels ≤15.0 μg/m³ also increased the risk for both outcomes compared to the same reference group. Subgroup analysis of high-risk pregnant women, including women aged > 35 years, with pre-pregnancy BMI (<18.5), pregnancy-induced hypertension, and nulliparous women, showed that the range of the critical PM_2.5 exposure threshold was 32.3–38.4 μg/m³ for preterm birth and 31.2–38.2 μg/m³ for LBW. This study highlights the significant association between PM_2.5 exposure and adverse pregnancy outcomes and suggests the need for targeted interventions to mitigate its effects on maternal and child health. Full article

Arsenic chronic exposure, particularly in its inorganic form, represents a significant public health concern. This study was conducted in Arica, the northernmost city in the country, whose inhabitants have been exposed to inorganic arsenic both naturally through drinking water and anthropogenically due to a toxic waste disposal site. We explored changes in inorganic arsenic levels in a cohort of pregnant women and their children over a decade, identifying exposure trends and their determinants. We used data on arsenic exposure through maternal urine samples during pregnancy, collected by the Health Authority between 2013 and 2016 (measurement 1), and followed up with assessments of their children in 2023 (measurement 2). Temporal changes in inorganic arsenic concentration were analyzed using the Wilcoxon Signed-Rank test, and a mixed linear regression model was employed to determine which factors contributed to urinary inorganic arsenic levels. We did not observe significant differences in mean arsenic concentrations between the two-time points (p = 0.4026). The mixed linear regression model revealed that children consuming bottled water had 8.3% lower urinary inorganic arsenic concentrations than those drinking tap water (95% CI: −15.36 to −0.54%). Additionally, children from ethnic groups had 8.64% higher inorganic arsenic concentrations (95% CI: 0.49 to 17.5%), while those with caregivers with higher education showed a 13.67% reduction (95% CI: −25.06 to −0.56%). Despite mitigation efforts, these findings underscore the ongoing risk of inorganic arsenic exposure among vulnerable populations. They further emphasize the importance of addressing natural arsenic contamination in water and implementing targeted interventions to reduce disparities associated with socioeconomic and demographic factors. Full article

Bisphenols (BPs) are a group of organic compounds used extensively in plastics, coatings, and epoxy resins; they have been of concern recently due to their endocrine-disrupting effects. Among these, bisphenol A (BPA) is the most studied. Regulatory measures, such as the ban on BPA use in baby bottles by the European Union and its restricted use in thermal paper, reflect the growing awareness of the health risks of BPA. To mitigate these risks, analogs such as bisphenol S (BPS), bisphenol F (BPF), and others (BPAF, BPAP, BPB, BPP, BPZ) have been developed as alternatives. Despite their intended safety, these analogs have been detected in environmental media, including indoor dust and thermal receipt paper, as well as in human biological samples. Studies report their presence in urine at levels comparable to BPA, with BPS and BPF found in 78% and 55% of samples, respectively. In addition, BPs have been found in human follicular fluid (FF) at concentrations that could exert some paracrine effects on ovarian function and reproductive health. With the increased global production of BPs, occupational exposure and environmental contamination also increase. This review summarizes what is currently known about the effects of BPs on the ovary and the mechanisms by which PBs exert ovarian toxicity, with a particular focus on oogenesis, folliculogenesis, and steroidogenesis. Further, this review emphasizes their influence on reproductive functions and the need for further biosafety evaluations. Full article

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds with fused aromatic rings, primarily derived from combustion processes and environmental pollutants. This narrative review discusses the most relevant studies on PAHs, focusing on their sources, environmental and occupational exposure, and effects on human health, emphasizing their roles as carcinogenic, mutagenic, and teratogenic agents. The primary pathways for human exposure to PAHs are through the ingestion of contaminated food (mainly due to some food processing methods, such as smoking and high-temperature cooking techniques), the inhalation of ambient air, and the smoking of cigarettes. Coke oven workers are recognized as a high-risk occupational group for PAH exposure, highlighting the need for appropriate strategies to mitigate these risks and safeguard worker health. PAHs are metabolized into reactive intermediates in the body, which can lead to DNA damage and promote the development of various health conditions, particularly in environments with high exposure levels. Chronic PAH exposure has been linked to respiratory diseases, as well as cardiovascular problems and immune system suppression. Furthermore, this review underscores the significant impact of PAHs on reproductive health. The results of the reported studies suggest that both male and female fertility can be compromised due to oxidative stress, DNA damage, and endocrine disruption caused by PAH exposure. In males, PAHs impair sperm quality, while, in females, they disrupt ovarian function, potentially leading to infertility, miscarriage, and birth defects. Fetal exposure to PAHs is also associated with neurodevelopmental disorders. Given the extensive and detrimental health risks posed by PAHs, this review stresses the importance of stringent environmental regulations, occupational safety measures, and public health initiatives to mitigate exposure and safeguard reproductive and overall health. Full article

Ambient air pollution has been associated with gestational diabetes mellitus (GDM); however, evidence regarding trimester-specific effects from China remains limited. This case–control study study analyzed data from pregnant women who delivered in Wuhan, China, between 2017 and 2022 (164 GDM cases and 731 controls), integrating geographic information, air quality measurements, and maternal characteristics. Using Inverse Distance Weighting interpolation and Generalized Linear Mixed Models (GLMM), we assessed associations between air pollutant exposure and GDM across different gestational periods. Results indicated that NO₂ demonstrated the strongest association with GDM compared to other pollutants. Specifically, increased NO₂ exposure was consistently associated with higher GDM risk throughout pregnancy. PM_2.5 exposure showed significant associations during early and mid-pregnancy, while SO₂ exposure was significantly associated with GDM risk exclusively in early pregnancy. Sensitivity analyses stratified by urban maternity status and maternal age revealed the stability of the study’s findings. These findings underscore the importance of reducing air pollution exposure during pregnancy and implementing targeted interventions for high-risk populations to prevent GDM development. Full article

Humidifier disinfectants (HDs), also known toxic indoor chemicals, have been linked to adverse health outcomes in children. However, their association with ADHD development remains largely unexplored. This study aimed to investigate the incidence of ADHD among HD claimants and assess the association between HD exposure and ADHD risk. A cohort of HD damage claimants born between 2002 and 2011 was established. ADHD cases and controls were identified using matched National Health Insurance Service claim data, with follow-ups required until age 10. ADHD incidence was calculated, and exposure characteristics—including the use of PHMG/PGH, humidifier distance and location, and cumulative and annual exposure duration—were analyzed. Cox proportional hazards analysis was performed, adjusting for sociodemographic factors and comorbidities. Among 1597 subjects, 84 were diagnosed with ADHD, resulting in an incidence density of 4.782 per 1000 person–years. Higher cumulative exposure duration and hours significantly increased the hazard ratio (HR) for ADHD. Additionally, exposure during the first three years after birth was associated with a higher HR for ADHD. These findings suggest that ADHD incidence is elevated in HD claimants and that HD exposure, particularly prolonged or early-life exposure, is associated with increased ADHD risk. Further research is required to confirm these findings in exposed cohorts and to elucidate the mechanisms underlying HD-related ADHD. Full article

Introduction: This study investigates associations between fine particulate air pollution (PM_2.5) exposure and thyroid hormone levels during pregnancy in Puerto Rican individuals, a vulnerable population facing socioeconomic and environmental disparities. Methods: This research draws on data from the PROTECT cohort study and involves 1040 participants to measure the effect of PM_2.5 on developmentally important thyroid hormones (TSH, T3, T4, and FT4). Pollution concentrations were linked to participant locations using EPA air quality data and analyzed across two visits during gestational weeks 16–20 and 24–28. Results: The results suggest that PM_2.5 exposure is positively associated with maternal T3, T4, and FT4 levels but not TSH. These effects vary by timing, with T3 showing stronger associations later in pregnancy and T4/FT4 earlier. Nonlinear dose–response relationships were observed, suggesting thresholds for certain hormones. Discussion: These findings support previous studies linking altered thyroid hormones to adverse birth outcomes and highlight the potential role of air pollution in disrupting maternal thyroid function and its implications for fetal development, calling for further research into mechanisms and interventions to mitigate these risks. Full article

Background: The effect of the long-term persistently elevated air pollutants, often referred to as air pollution waves, on sexual function has not been sufficiently addressed. Methods: This nationwide cross-sectional study involved 12,157 participants, with 5496 females and 5039 males. PM waves were characterized by daily average PM concentrations surpassing Grade II thresholds of China’s ambient air quality standards (PM_2.5 > 75 μg/m³, PM₁₀ > 150 μg/m³) for three or more consecutive days (3–8 days). Male sexual function was assessed through the International Index of Erectile Function-5 (IIEF-5) and the Premature Ejaculation Diagnostic Tool (PEDT), while female sexual function was evaluated using the Female Sexual Function Index (FSFI). A multivariate linear regression model was employed to investigate the link between PM wave exposure and sexual function. Results: Exposure to PM₁₀ waves, defined as 3 (β = −0.0145, 95%CI = −0.0280, −0.0010), 4 (β = −0.0145, 95%CI = −0.0280, −0.0010), 5 (β = −0.0193, 95%CI = −0.0371, −0.0015), 6 (β = −0.0218, 95%CI = −0.0415, −0.0021), 7 (β = −0.0243, 95%CI = −0.0458, −0.0028), and 8 (β = −0.0243, 95%CI = −0.0458, −0.0028) consecutive days, negatively impacted IIEF-5 scores and male sexual function. Moreover, depression levels, as evaluated by the PHQ-9, played a mediating role in the connection between PM₁₀ waves and IIEF-5 scores. The potentially vulnerable subgroups were the younger 20–30 and the low-income groups. Conclusions: Our results suggest for the first time that PM₁₀ waves are associated with decreased IIEF-5 scores, which are mediated by depression score PHQ-9, informing policy formulation for public health interventions and individual safeguarding. Full article

Developmental exposure to benzo[a]pyrene (BaP), a ubiquitous environmental pollutant, has been linked to various toxic effects, including multigenerational behavioral impairment. While the specific mechanisms driving BaP neurotoxicity are not fully understood, recent work highlights two important determinants of developmental BaP neurotoxicity: (1) the aryl hydrocarbon receptor (AHR), which induces host metabolism of BaP, and (2) the gut microbiome, which may interact with BaP to affect its metabolism, or be perturbed by BaP to disrupt the gut–brain axis. We utilized the zebrafish model to explore the role of AHR, the gut microbiome, and their interaction, on BaP-induced neurotoxicity. We tested (1) how developmental BaP exposure and AHR2 perturbation in zebrafish link to adult behavior, (2) how these variables associate with the structure and function of the adult zebrafish gut metagenome, and (3) whether these associations are multigenerational. Our findings reveal a reticulated axis of association between BaP exposure, developmental AHR2 expression, the zebrafish gut metagenome, and behavior. Results indicate that AHR2 is a key modulator of how BaP elicits neurotoxicity and microbiome dysbiosis. Additionally, this axis of association manifests generationally. These findings demonstrate the importance of studying pollutant–microbiome interactions and elucidate the role of specific host genes in neurotoxicity and dysbiosis. Full article