Engineered nanomaterials in rivers--exposure scenarios for Switzerland at high spatial and temporal resolution

Probabilistic material flow analysis and graph theory were combined to calculate predicted environmental concentrations (PECs) of engineered nanomaterials (ENMs) in Swiss rivers: 543 river sections were used to assess the geographical variability of nano-TiO₂, nano-ZnO and nano-Ag, and flow measurements over a 20-year period at 21 locations served to evaluate temporal variation. A conservative scenario assuming no ENM removal and an optimistic scenario covering complete ENM transformation/deposition were considered. ENM concentrations varied by a factor 5 due to uncertain ENM emissions (15%-85% quantiles of ENM emissions) and up to a factor of 10 due to temporal river flow variations (15%-85% quantiles of flow). The results indicate highly variable local PECs and a location- and time-dependent risk evaluation. Nano-TiO₂ median PECs ranged from 11 to 1′623 ng L⁻¹ (conservative scenario) and from 2 to 1′618 ng L⁻¹ (optimistic scenario). The equivalent values for nano-ZnO and nano-Ag were by factors of 14 and 240 smaller.     

Turner syndrome-omphalocele association: Incidence,karyotype, phenotype and fetal outcome

Objective

Omphalocele is known to be associated with genetic anomalies like trisomy 13, 18 and Beckwith–Wiedemann syndrome, but not with Turner syndrome (TS). Our aim was to assess the incidence of omphalocele in fetuses with TS, the phenotype of this association with other anomalies, their karyotype, and the fetal outcomes.

Method

Retrospective multicenter study of fetuses with confirmed diagnosis of TS. Data were extracted from a detailed questionnaire sent to specialists in prenatal ultrasound.

Results

680 fetuses with TS were included in this analysis. Incidence of small omphalocele in fetuses diagnosed ≥12 weeks was 3.1%. Including fetuses diagnosed before 12 weeks, it was 5.1%. 97.1% (34/35) of the affected fetuses had one or more associated anomalies including increased nuchal translucency (≥3 mm) and/or cystic hygroma (94.3%), hydrops/skin edema (71.1%), and cardiac anomalies (40%). The karyotype was 45,X in all fetuses. Fetal outcomes were poor with only 1 fetus born alive.

Conclusion

TS with 45,X karyotype but not with X chromosome variants is associated with small omphalocele. Most of these fetuses have associated anomalies and a poor prognosis. Our data suggest an association of TS with omphalocele, which is evident from the first trimester.     

The release of engineered nanomaterials to the environment

There is scientific agreement that engineered nanomaterial (ENM) production, use and disposal lead to environmental release of ENM. However, very little is known on emissions of ENM to the environment. Currently, techniques are lacking to quantitatively monitor ENM emissions to and concentrations in the environment, and hence data on emissions and environmental concentrations are scarce. One of the few available studies reports the detection of nano-TiO(2) in water leaching from exterior facades. Some experimental evidence is available on the release of nanosized materials from commercial textiles during washing. A handful of modeling studies have investigated ENM release to the environment. These studies modeled either the release of ENMs to the environment from ENM containing products during the consumer usage, or the release throughout the whole life cycle of ENM and ENM-containing products. Sewage sludge, wastewater, and waste incineration of products containing ENM were shown to be the major flows through which ENMs end up in the environment. However, reliable data are particularly lacking on release during ENM production and on the application amounts and empirical information on release coefficients for all life cycle stages and environmental compartments. Quantitative data linking occupational exposure measurements and ENM emission flows into the environment are almost completely missing. Besides knowing the amounts of ENM released into the environment, it is equally important to investigate in what form ENMs are released. First results show that much of the ENM released from products is present in matrix-bound form, but that also some fraction is released as single, dispersed nanoparticles.