Including non-dietary sources into an exposure assessment of the European Food Safety Authority: the challenge of multi-sector chemicals such as Bisphenol A

In the most recent risk assessment for Bisphenol A for the first time a multi-route aggregate exposure assessment was conducted by the European Food Safety Authority. This assessment includes exposure via dietary sources, and also contributions of the most important non-dietary sources. Both average and high aggregate exposure were calculated by source-to-dose modeling (forward calculation) for different age groups and compared with estimates based on urinary biomonitoring data (backward calculation). The aggregate exposure estimates obtained by forward and backward modeling are in the same order of magnitude, with forward modeling yielding higher estimates associated with larger uncertainty. Yet, only forward modeling can indicate the relative contribution of different sources. Dietary exposure, especially via canned food, appears to be the most important exposure source and, based on the central aggregate exposure estimates, contributes around 90% to internal exposure to total (conjugated plus unconjugated) BPA. Dermal exposure via thermal paper and to a lesser extent via cosmetic products may contribute around 10% for some age groups. The uncertainty around these estimates is considerable, but since after dermal absorption a first-pass metabolism of BPA by conjugation is lacking, dermal sources may be of equal or even higher toxicological relevance than dietary sources.info:eu-repo/semantics/publishedVersio

Subsequent pregnancy outcomes after open maternal-fetal surgery for myelomeningocele

BACKGROUND Open maternal-fetal surgery for fetal myelomeningocele results in reduction in neonatal morbidity related to spina bifida but may be associated with fetal, neonatal, and maternal complications in subsequent pregnancies. OBJECTIVE The objective of this study was to ascertain obstetric risk in subsequent pregnancies after open maternal-fetal surgery for fetal myelomeningocele closure. STUDY DESIGN An international multicenter prospective observational registry created to track and report maternal, obstetric, fetal/neonatal, and subsequent pregnancy outcomes following open maternal-fetal surgery for fetal myelomeningocele was evaluated for subsequent pregnancy outcome variables. Institutional Review Board approval was obtained for the registry. RESULTS From 693 cases of open maternal-fetal surgery for fetal myelomeningocele closure entered into the registry, 77 subsequent pregnancies in 60 women were identified. The overall live birth rate was 96.2%, with 52 pregnancies delivering beyond 20 weeks gestational age and median gestational age at delivery of 37 (36.3-37.1) weeks. The uterine rupture rate was 9.6% (n = 5), resulting in 2 fetal deaths. Maternal transfusion was required in 4 patients (7.7%). CONCLUSION The risk of uterine rupture or dehiscence in subsequent pregnancies with associated fetal morbidity after open maternal-fetal surgery is significant, but is similar to that reported for subsequent pregnancies after classical cesarean deliveries. Future pregnancy considerations should be included in initial counseling for women contemplating open maternal-fetal surgery