The effect of pre-pregnancy hair dye exposure on infant birth weight: a nested case-control study

Clinical, metabolomic, and proteomic profiles associated with reproductive outcomes in unexplained recurrent pregnancy loss

Song Z et al., 2026 · Frontiers in endocrinology · Free full text on PubMed Central

To identify preconception clinical and multi-omics factors associated with conception and early pregnancy loss in women with unexplained recurrent pregnancy loss (URPL). In this prospective cohort study, 149 women with URPL selected from 420 outpatients based on guideline-recommended criteria were enrolled between November 2024 and May 2025 and followed-up for 12 months. Preconception fasting plasma was analyzed for clinical biomarkers, untargeted metabolomics, and data-independent acquisition proteomics. Outcomes included conception, ongoing pregnancy beyond 12 weeks and early pregnancy loss before 12 weeks. Multivariable logistic regression was used to evaluate the associations of clinical and multi-omics factors with reproductive outcomes, adjusting for maternal age, body mass index, number of prior losses, and use of assisted reproductive technology. Of 149 women, 99 conceived (66.4%) during the follow-up. By 12 weeks of gestation, 67 (67.7%) had ongoing pregnancies and 32 (32.3%) experienced early pregnancy loss. Higher testosterone was associated with lower probability of conception (adjusted odds ratio [aOR] 0.50, 95% confidence interval [CI] 0.28-0.89, p = 0.019). Women who conceived showed higher levels of progesterone-related metabolites, including 17-hydroxyprogesterone (fold change, FC = 3.89), pregnanediol 3-O-glucuronide (FC = 2.37), and pregnanetriol 3α-O-β-D-glucuronide (FC = 2.39). Among women who conceived, higher prolactin was associated with higher odds of early pregnancy loss (aOR 1.09, 95% CI 1.01-1.18, p = 0.036), and anti-phosphatidylserine/prothrombin showed a borderline association (aOR 1.07, 95% CI 1.00-1.14, p = 0.052). Early pregnancy loss was characterized by lower bile acid-related metabolites and higher caffeine and methylxanthine metabolites. Proteomic analysis showed enrichment of bile acid biosynthetic process. After adjustment, higher 7α,12α-dihydroxy-3-oxocholest-4-en-27-oic acid was associated with lower odds of early pregnancy loss (aOR 0.64, 95% CI 0.44-0.95, p = 0.025). Higher testosterone was associated with lower odds of conception. Among women who conceived, early pregnancy loss was associated with higher prolactin, borderline higher anti-PS/PT, lower bile acid-related metabolites, and higher caffeine-related metabolites, with 7α,12α-dihydroxy-3-oxocholest-4-en-27-oic acid identified as an exploratory metabolomic candidate. These findings suggest that potential androgen-related biology, prolactin, non-criteria antiphospholipid antibodies, and bile acid metabolism may be associated with reproductive outcomes in URPL, warranting validation in independent cohorts.

Global, regional, and national burden of breast cancer among females, 1990-2023, with forecasts to 2050: a systematic analysis for the Global Burden of Disease Study 2023

GBD 2023 Breast Cancer Collaborators, 2026 · The Lancet Oncology · Free to read

Lipid metabolism drives dietary effects on T cell ferroptosis and immunity

Wang N et al., 2026 · Nature

Assessing the impact of real-world environmental factors on low-cost PM2.5 monitor performance by comparing calibration before and after deployment

Fang R et al., 2025 · Sci Total Environ

Understanding and mitigating health risks from poor indoor air quality, particularly fine particulate matter (PM2.5), is critical, yet conventional monitoring methods are costly and require skilled operators. Low-cost sensors (LCS) offer an accessible alternative; however, their accuracy under varying environmental conditions remains uncertain. This study evaluates how humidity, temperature, deployment duration, and concentration levels affect the calibration accuracy of low-cost PM2.5 monitors. Nineteen Plantower PMS 3003 sensors deployed in 11 Salt Lake County homes participating in the Green & Healthy Homes Initiative were calibrated before and after residential deployment using a TSI DustTrak aerosol monitor. Linear and Lasso regression analyses were performed to evaluate the influence of environmental factors on calibration parameters. Significant variability was observed in environmental conditions. Higher humidity (p = 0.0197) and longer deployment durations (p = 0.0178) significantly altered calibration slopes, while mean PM2.5 exposure (p = 0.0040) was strongly associated with intercept adjustments. These findings emphasize the need to account for environmental factors in calibration models to improve LCS accuracy and reliability. Environmental conditions significantly impact the performance of low-cost PM2.5 sensors. Modeling these impacts can streamline the calibration process, making it more efficient and cost-effective. Future research should focus on refining calibration models and exploring additional environmental factors to optimize LCS performance.

Dermal exposure to bisphenols in pregnant women's and baby clothes: Risk characterization

Herrero M et al., 2023 · Science of The Total Environment

Textile manufacturing consists of a multiple-step process in which a wide range of chemicals is used, some of them remaining in the final product. Bisphenols (BPs) are non-intentionally added compounds in textiles, whose prolonged skin contact may mean a significant source of daily human exposure, especially in vulnerable groups of the population. The present study aimed to determine the levels of bisphenol A (BPA) and some BP analogs (BPB, BPF, and BPS) in 120 new clothes commercialized in Spain for pregnant women, newborns, and toddlers. In addition, exposure assessment and risk characterization were also carried out. Traces of BPA were found in all the samples, with a median concentration of 7.43 ng/g. The highest values were detected in textile samples made of polyester. Regarding natural fibers, higher concentrations of BPs were observed in garments made of conventional cotton than in those made of organic cotton, with a significant difference for BPS (1.24 vs. 0.76 ng/g, p < 0.05). Although toddlers have a larger skin-area-to-body-weight ratio, pregnant women showed higher exposure to BPs than children. Anyhow, the non-carcinogenic risks associated with BPA exposure were below the unity, even under the upper-bound scenario. However, risks could be underestimated because other exposure routes were not considered in this study. The use of BPA has been restricted in some food-related products; therefore, BPA should also be regulated in the textile industry.

Assessment of urinary aromatic amines in Brazilian pregnant women and association with DNA damage: Influence of genetic diversity, lifestyle, and environmental and socioeconomic factors

Souza MCO et al., 2023 · Environmental Pollution

Aromatic amines (AAs) are polar organic chemicals with a wide environmental distribution originating from various sources, such as tobacco smoke, diesel exhaust, and dermal absorption from textile products with azo dyes. The toxicity profile of AAs is directly related to the amino group's metabolic activation and the generation of the reactive intermediate, forming DNA adducts and potential carcinogenicity. Urinary levels of 8-hydroxy-2'-deoxyguanosine (8OHdG) are an important biomarker of DNA damage. Since AAs have been shown to cross the placental barrier, being a risk factor for adverse birth outcomes, prenatal exposure is a great public health concern. The present study aimed to measure the urinary levels of 58 AAs in Brazilian pregnant women (n = 300) and investigated the impact of this exposure on DNA damage by quantifying 8OHdG levels. The influence of tobacco smoke exposure and dermal absorption of AAs by clothes on urinary levels was also assessed. The results showed a 100% detection rate for eight AAs, two of them regulated by the European Union (2,6-dimethylaniline and 2,4-diaminotolune). Hundreds of AAs may be derived from aniline, which here showed a median of 1.38 ng/mL. Aniline also correlated positively with 2,6-dimethylaniline, p-aminophenol, and other AAs, suggesting exposure to multiple sources. The present findings suggest that both tobacco smoke and dermal contact with clothes containing azo dyes are potential sources that might strongly influence urinary levels of AAs in Brazilian pregnant women. A multiple regression linear model (R2 = 0.772) suggested that some regulated AAs (i.e., 2-naphthylamine and 4-aminobiphenyl), nicotine, smoke habit, age, and Brazilian region could induce DNA damage occurrence, increasing the levels of 8OHdG. Given the limited available data on human exposure to carcinogenic AAs, as well as the lack of toxicological information on those non-regulated, further studies focused on measuring their levels in human fluids and the potential exposure sources are clearly essential.

Birth Outcomes of Neonates Exposed to Marijuana in Utero: A Systematic Review and Meta-analysis

Marchand G et al., 2022 · JAMA network open · Free full text on PubMed Central

While some studies have found an association between marijuana use and adverse neonatal outcomes, results have not been consistent across all trials. To assess available data on neonatal outcomes in marijuana-exposed pregnancies. PubMed, Medline, ClinicalTrials.gov, Cochrane, Scopus, and Web of Science were searched from each database's inception until August 16, 2021. All interventional and observational studies that included pregnant women who were exposed to marijuana compared with pregnant women who were not exposed to marijuana and that reported neonatal outcomes were included. Reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline. Data were extracted by 2 authors for all outcomes, which were pooled using a random-effects model as mean difference or risk ratio (RR) and 95% CI. Data were analyzed from August through September 2021. All outcomes were formulated prior to data collection. Outcomes included incidence of birth weight less than 2500 g, small for gestational age (defined as less than the fifth percentile fetal weight for gestational age), rate of preterm delivery (defined as before 37 weeks' gestation), gestational age at time of delivery, birth weight, incidence of neonatal intensive care unit (NICU) admission, Apgar score at 1 minute, Apgar score at 5 minutes, incidence of an Apgar score less than 7 at 5 minutes, fetal head circumference, and fetal length. Among 16 studies including 59 138 patients, there were significant increases in 7 adverse neonatal outcomes among women who were exposed to marijuana during pregnancy vs those who were not exposed during pregnancy. These included increased risk of birth weight less than 2500 g (RR, 2.06 [95% CI, 1.25 to 3.42]; P = .005), small for gestational age (RR, 1.61 [95% CI, 1.44 to 1.79]; P < .001), preterm delivery (RR, 1.28 [95% CI, 1.16 to 1.42]; P < .001), and NICU admission (RR, 1.38 [95% CI, 1.18 to 1.62]; P < .001), along with decreased mean birth weight (mean difference, -112.30 [95% CI, -167.19 to -57.41] g; P < .001), Apgar score at 1 minute (mean difference, -0.26 [95% CI, -0.43 to -0.09]; P = .002), and infant head circumference (mean difference, -0.34 [95% CI, -0.63 to -0.06] cm; P = .02). This study found that women exposed to marijuana in pregnancy were at a significantly increased risk of some adverse neonatal outcomes. These findings suggest that increasing awareness about these risks may be associated with improved outcomes.

Human health risks from textile chemicals: a critical review of recent evidence (2019-2025)

Rovira J et al., 2025 · Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering

Global textile production, driven by consumer demand, raises significant concerns about exposure to chemicals in clothing and related products. This review synthesizes evidence (2019-2025) on hazardous substances in textiles, including dyes, plasticizers, per- and polyfluoroalkyl substances (PFAS), and metals, and identifies and categorizes their associated human health risks. Emerging evidence highlights microfibers as critical vectors for chemical exposure via inhalation and dermal routes, necessitating updated risk assessments. Focusing on dermal absorption as the primary exposure route, risks to vulnerable populations (e.g., infants, pregnant women) and gaps in regulatory frameworks are highlighted. The current analysis reveals that chronic exposure to chemical mixtures in textiles remains poorly understood, with current safety assessments often neglecting synergistic effects. Key findings include elevated risks from phthalates in infant clothing, PFAS in water-repellent fabrics, and carcinogenic aromatic amines (AAs) from azo dyes. We underscore the urgency of harmonized global regulations, advanced biomonitoring, and sustainable alternatives (e.g., enzymatic dyes, biodegradable finishes). Public awareness initiatives and stricter enforcement of certifications like OEKO-TEX(®) or GOTS are critical to mitigating risks. Interdisciplinary collaboration among textile technologists, toxicologists, and public health experts is essential to develop safer textile alternatives and integrate health-centric approaches into sustainability agendas, safeguarding consumers, workers, and ecosystems.