Microplastic Contamination in the Human Placenta
Notice bibliographique
Résumé
Introduction: The widespread presence of plastics in our environment poses a growing concern as they may pose risks to human and environmental health. Microplastics (MPs) are small particles generated through fragmentation of larger plastic items. The presence of MPs particles has been reported in the human placenta, an organ essential for pregnancy and fetal development. The presence of MP contamination of the womb raises the possibility of adverse effects on the developing fetus with potential life-long consequences. This thesis seeks to investigate this issue through: 1) A review aimed to examine the current state of knowledge on the effects of exposure to MP on maternal and fetal health within the DOHaD framework; 2) A study conducted to confirm and further the reports of microplastics in human placentas through a study, in a Canadian setting, comparing MPs exposure to delivery methods. Methods: 1) A review was conducted of the current literature on microplastic contamination in human reproductive tissues, and the resulting reproductive consequences of exposure. 2) Placentas (n=10) were collected from singleton, uncomplicated pregnancies. Placentas were collected from vaginal (n=5) and cesarean section (n=5) deliveries within a plastics-reduced clinical setting. Placental tissue biopsies were micro-dissected under plastic-reduced conditions - from basal plate, chorionic villous and chorionic plate. Samples were chemically digested and filtered through glass microfiber filters and the retained particles were identified and characterized using Raman microspectroscopy. iii Results: 1) The review reports multiple lines of evidence that suggest that MP-exposure prior to or during pregnancy can contaminate various internal tissues (including those of the fetus) and may result in potential adverse effects on fertility, fetal development and long-term health of the exposed fetus. More importantly, the available evidence is limited and several significant gaps in knowledge were identified. 2) Microplastics composed of various polymer types were detected in placentas from both delivery types (vaginal or caesarian), with polyethylene being the most common. In addition, non-plastic foreign particles including graphite, lead oxide and black carbon were observed in a higher frequency than microplastics. Notably, both microplastic and non-microplastic particles were found in all placentas sampled with variations in the number of particles. Particles both plastic and non-plastic were observed in placenta regions of maternal and fetal circulation suggesting that these can pass through the placenta into fetal tissues. Conclusion: This thesis provides evidence that the human placenta can serve as a reservoir for the accumulation of a variety of foreign particles during pregnancy. The potential human health impacts of such particles in general or on fetal development, in particular, are unknown but is a critical question for future work to understand the health consequences of plastic pollution.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,002 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,003 | 0,002 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,002 | 0,001 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».