Presence, behaviour, and risk assessment of volatile methylsiloxanes in wastewater: A year-long comprehensive study within a wastewater treatment plant.

The awareness of possible environmental hazards caused by the widespread global use of volatile methylsiloxanes (VMSs) in personal care products (PCPs) and industrial processes has been increasing. Sewage containing these compounds may reach wastewater treatment plants (WWTPs), which are hotspots of their release into the environment. The levels, distribution, and potential risks of VMSs were studied in an unprecedently comprehensive sampling strategy (four seasonal campaigns) along the water line of a WWTP: the main influent entrance (SA1), after the preliminary treatment (SA2), after the primary treatment (SA3) and after the secondary treatment (the treated effluent; SA4).

A review of bioaccumulation of volatile methylsiloxanes in aquatic ecosystems.

Volatile methylsiloxanes (VMSs) are found in a broad range of industrial and consumer products. They are categorized as "high production volume chemicals" by the U.S.

Using Design of Experiments to Optimize a Screening Analytical Methodology Based on Solid-Phase Microextraction/Gas Chromatography for the Determination of Volatile Methylsiloxanes in Water.

Volatile methylsiloxanes (VMSs) constitute a group of compounds used in a great variety of products, particularly personal care products. Due to their massive use, they are continually discharged into wastewater treatment plants and are increasingly being detected in wastewater and in the environment at low concentrations. The aim of this work was to develop and validate a fast and reliable methodology to screen seven VMSs in water samples, by headspace solid-phase microextraction (HS-SPME) followed by gas chromatography with flame ionization detection (GC-FID).

Headspace solid-phase microextraction based on the metal-organic framework CIM-80(Al) coating to determine volatile methylsiloxanes and musk fragrances in water samples using gas chromatography and mass spectrometry.

A headspace solid-phase microextraction (HS-SPME) method was developed using the metal-organic framework (MOF) CIM-80(Al) as extraction phase and in combination with gas chromatography-mass spectrometry (GC-MS) for the simultaneous determination of 6 methylsiloxanes and 7 musk fragrances in different environmental waters. The chromatographic separation was optimized in different GC instruments equipped with different detectors, allowing the correct separation and identification of the compounds. The HS-SPME method was optimized using a Box-Behnken experimental design, while the validation was carried out together with the most suitable commercial fiber (divinylbenzene/polydimethylsiloxane) for comparison purposes.

Study of Testicular Structure in Fetuses with Prune Belly Syndrome.

Purpose: To compare the structure of the testis in fetuses with prune belly syndrome (PBS) to normal controls.

Materials And Methods: We studied 6 testes obtained from 3 fetuses with PBS and 14 testes from 7 male fetuses. The testicular specimens were cut into 5-m thick sections and stained with hematoxylin and eosin (HE), to observe the seminiferous tubules; Weigert's solution to observe elastic fibers; and picrosirius red to observe collagen.

Is there a trans-abdominal testicular descent during the second gestational trimester? Study in human fetuses between 13 and 23 weeks post conception.

Objectives: To confirm if a real inner descend of testis occurs, correlating the testicular position with fetal parameters and analyzing the position of the testes relative to the internal ring.

Material And Methods: Twenty nine human fetuses between 13 and 23 weeks post conception (WPC) were studied. The fetuses were carefully dissected with the aid of a stereoscopic lens with 16/25X magnification and testicular position observed.