Daily Cosmetic Research Analysis
Advances span non-animal genotoxicity testing, symptom-focused management of xerostomia in older adults, and mitigation of phthalate exposures from cosmetics during pregnancy. A 3D human skin platform strengthens regulatory-aligned genotoxicity assays, a registered meta-analysis supports topical agents for dry mouth symptom relief, and an integrative review details endocrine mechanisms, biomarkers, and safer-substitute strategies for cosmetic phthalates.
Summary
Advances span non-animal genotoxicity testing, symptom-focused management of xerostomia in older adults, and mitigation of phthalate exposures from cosmetics during pregnancy. A 3D human skin platform strengthens regulatory-aligned genotoxicity assays, a registered meta-analysis supports topical agents for dry mouth symptom relief, and an integrative review details endocrine mechanisms, biomarkers, and safer-substitute strategies for cosmetic phthalates.
Research Themes
- Non-animal, human-relevant safety assessment for cosmetic ingredients
- Topical therapies for xerostomia in older adults
- Endocrine-disrupting exposures from cosmetics in pregnancy: mechanisms and mitigation
Selected Articles
1. Investigating the application of 3D skin models in micronucleus assay and comet assay.
Using EpiSkin-MNT and T-Skin, the authors demonstrate robust, dose-responsive micronucleus and comet assay readouts with improved sensitivity when DNA repair is inhibited by aphidicolin. Results support 3D human skin as a reproducible, human-relevant platform to reduce false positives and advance regulatory-aligned, non-animal genotoxicity testing.
Impact: Provides a practical, human-relevant alternative to animal testing with clear methodological advances that align with regulatory trends in cosmetic safety assessment.
Clinical Implications: While preclinical, these methods can improve the safety evaluation of skin-exposed products by reducing false positives and increasing human relevance, ultimately informing dermatologic risk assessments and product labeling.
Key Findings
- 3D reconstructed human skin integrated with MNT and comet assays yields reproducible, dose-dependent genotoxicity readouts.
- Negative controls showed no significant response, while positive controls demonstrated clear increases in micronucleus and comet parameters.
- Aphidicolin (DNA repair inhibitor) enhanced comet assay sensitivity for DNA damage detection.
Methodological Strengths
- Use of physiologically relevant 3D human skin models (EpiSkin-MNT, T-Skin)
- Orthogonal genotoxicity endpoints (micronucleus frequency and comet parameters) with dose-response
Limitations
- Preclinical in vitro setting limits direct clinical translation.
- The number and diversity of reference chemicals and inter-laboratory validation were not detailed.
Future Directions: Conduct inter-laboratory ring trials, expand reference chemical panels (including cosmetic ingredients), and correlate in vitro genotoxicity with human biomarkers to define performance standards.
Conventional two-dimensional (2D) cell culture models for genotoxicity testing often yield false-positive results due to their limited metabolic capacity and lack of tissue architecture. Three-dimensional (3D) reconstructed human skin models offer a more physiologically relevant alternative for evaluating genotoxicity. In this study, the reproducibility, dose-response, and predictive performance of the micronucleus test (MNT) and comet assay were systematically assessed using 3D skin models EpiSkin-MNT and T-Skin. A panel of reference chemicals, including both genotoxic and non-genotoxic agents, was tested. Cytotoxicity was measured using ATP and adenylate kinase (AK) assays; genotoxicity endpoints included micronucleus frequency and comet assay parameters such as tail intensity and tail moment. Both assays exhibited clear dose-dependent increases in genotoxic markers for positive controls, while negative controls showed no significant response. Use of the DNA repair inhibitor aphidicolin in the comet assay enhanced the sensitivity of DNA damage detection. The integration of 3D skin models with MNT and comet assays provides a robust, reproducible, and physiologically relevant platform for genotoxicity assessment, supporting the transition from animal-based methods and aligning with regulatory trends.
2. Efficacy of topical treatments for xerostomia in older adults: a systematic review and meta-analysis.
Among 19 included studies (17 RCTs), seven contributed to meta-analysis showing that pilocarpine mouthwash/mucoadhesive tablets, 1% malic acid, and thyme-honey rinses significantly reduce xerostomia symptoms versus placebo. Symptomatic benefit did not translate into consistent increases in salivary flow, highlighting a role for topical agents in multimodal, comfort-focused care for elders.
Impact: Clinically actionable synthesis with registration and meta-analytic methods provides evidence to guide topical choices for xerostomia when systemic therapies are unsuitable.
Clinical Implications: Consider pilocarpine formulations, 1% malic acid, or thyme-honey rinses for symptomatic relief in older adults with xerostomia, especially when systemic sialogogues are contraindicated; set expectations that salivary flow may not improve.
Key Findings
- Seven RCTs meta-analyzed showed significant symptom reduction with pilocarpine (mouthwash/mucoadhesive), 1% malic acid, and thyme-honey rinses versus placebo (Z = 5.78; p < 0.001).
- Nineteen prospective studies identified; symptom relief consistent, but salivary flow-rate improvements were inconclusive.
- PICO-driven search across multiple databases; PROSPERO registered (CRD42024532652).
Methodological Strengths
- Registered protocol and meta-analytic synthesis
- Multiple RCTs with placebo comparators and standardized symptom outcomes
Limitations
- Heterogeneity and limited number of RCTs in the meta-analysis.
- Insufficient evidence on objective salivary flow-rate improvements.
Future Directions: Standardize xerostomia outcomes (symptoms and flow), include longer follow-up, and compare head-to-head topical regimens in geriatric populations.
OBJECTIVE: This systematic review and meta-analysis evaluated the efficacy of topical applications, compared to placebo or other treatments, for the management of xerostomia in older adults. The PICO focus question set for this study was, "What is the most effective topical therapy as opposed to systemic or other therapies for the treatment of xerostomia and salivary gland hypofunction, in elderly patients?" DATA AND SOURCES: Electronic searches of PubMed, CENTRAL, MEDLINE and Web of Science were conducted using the PICO framework. 7459 studies published until April of 2024 were screened. Prospective studies reporting on treatment of xerostomia and hyposalivation in elderly patients were selected. STUDY SELECTION: Nineteen studies [17 randomized controlled trials (RCTs) and 2 quasi-experimental studies] were included. Seven RCTs provided information for meta-analysis. Pilocarpine mouthwash/mucoadhesive tablets, 1 % malic acid, thyme-honey mouth rinse, significantly reduced xerostomia when compared against placebo (Z = 5.78; p < 0.001; I CONCLUSIONS: This systematic review concluded that the topical applications for the treatment of dry mouth provided symptomatic relief in older adults, however, their role in the improvement of salivary flow rates was inconclusive due to a lack of sufficient evidence. CLINICAL SIGNIFICANCE: Topical applications in elderly patients with dry mouth may offer effective symptom relief, particularly when systemic approaches are contraindicated. Although, these interventions may not significantly improve salivation, clinicians should consider them as part of a multimodal approach to improve patients' comfort and quality of life. PROSPERO REGISTRATION: CRD42024532652.
3. Exposure risks to phthalates by cosmetics and personal care products in pregnant women and early life: Urinary levels, mechanisms, biomarkers, and mitigation strategies: a review.
This review synthesizes PCP- and cosmetic-related phthalate exposure patterns in pregnancy and early life, highlighting predominant metabolites (MEP > MnBP > MEHHP), endocrine and organ toxicities, and mechanistic hormone disruptions. It proposes biomarker panels (DNA methylation, EV-miRNAs, metabolic indices, MDA) and substitution of high-risk phthalates with citrates to mitigate exposure.
Impact: Provides an actionable framework linking exposure sources, mechanisms, and biomarkers with practical mitigation strategies for maternal-fetal health in the context of cosmetic use.
Clinical Implications: Supports counseling pregnant patients on limiting high-phthalate cosmetics (e.g., certain lipsticks, deodorants, nail polishes), monitoring relevant biomarkers in research settings, and advocating for safer substitutions in product formulations.
Key Findings
- Continuous or high-quantity use of cosmetics/PCPs (notably lipstick, deodorants, nail polish) associates with higher urinary MEP > MnBP > MEHHP in pregnant women and early-life exposure via placenta and breast milk.
- Early-life risks include endocrine dysregulation (cholesterol, thyroid, estrogen, androgen), hepatic/renal/thyroid toxicity, skin inflammation, and adverse reproductive outcomes (prematurity, miscarriage, low birth weight, early puberty).
- Mechanisms center on maternal/placental hormone disruptions (e.g., GnRH, estrogen) and decreases in SHBG and testosterone; biomarkers include DNA methylation changes, EV-miRNAs, maternal glycemia/lipids, and MDA.
- Mitigation includes substituting high-risk phthalates with less toxic alternatives (e.g., citrates) and recommending early-life biomarker monitoring.
Methodological Strengths
- Integrative synthesis spanning exposure pathways, mechanisms, biomarkers, and mitigation strategies
- Focus on maternal–fetal–infant continuum relevant to public health and regulation
Limitations
- Narrative review without explicit systematic methods or quantitative synthesis; potential selection bias.
- Lack of standardized exposure metrics and limited causal inference from observational associations.
Future Directions: Develop PRISMA-compliant systematic reviews with meta-analyses, harmonize exposure metrics, and test substitution strategies with longitudinal maternal–child cohorts.
The increasing use of personal care products (PCPs) and cosmetics have increased the risk of exposure to phthalates, especially in the early stages of life for maternal-fetal-infant. This review aimed to determine the phthalates exposure risk through the consumption of PCPs and cosmetics in Pregnant women and early life, determine the mechanisms, biomarkers, and mitigation strategies for phthalates. The highest phthalates exposure levels of pregnant women (as well as fetal exposure through placenta and infants through breast milk) who used PCPs and cosmetics continuously or in larger quantities, especially lipstick, deodorants, and nail polish, were related to MEP˃ MnBP˃ MEHHP, respectively. The greatest phthalates exposure health risks in early life include hormonal disorders, especially cholesterol, thyroid, estrogen, and androgen, and toxicity to the liver, kidney, and thyroid, skin inflammation and irritation, and reproductive system toxicity, including premature birth and menopause, miscarriage, low birth weight and height, and early puberty. Maternal and placenta hormones disorders, such as gonadotropin-releasing hormone (GnRH) and estrogen, and decreases in steroid hormones such as SHBG (sex-hormone binding globulin) and testosterone, were the main mechanisms for phthalates exposures. Suitable biomarkers for assessing phthalates exposure by PCPs were changes in DNA methylation, placental-derived extracellular vehicles related to microRNAs (EV-miRNAs), maternal glycemia and lipid profiles, and malondialdehyde (MDA) level. Replacing high-risk phthalates with less toxic substances, like citrates, during the PCPs production is a suitable way to lower phthalate exposure. It is recommended that monitoring of phthalates biomarkers in the early years of life in future studies.