A reliable procedure for decontamination before thawing of human specimens cryostored in liquid nitrogen: three washes with sterile liquid nitrogen (SLN2).

Objective: To report a washing procedure, to be performed as frozen specimens are taken out of cryobanks, to minimize the risk of hypothetical culture contamination during thawing.

Design: Basic research.

Setting: Private assisted reproduction center.

Sterilization of liquid nitrogen with ultraviolet irradiation for safe vitrification of human oocytes or embryos.

Objective: To evaluate the efficacy of ultraviolet (UV) irradiation for rapid microbial decontamination of liquid nitrogen (LN2).

Design: Basic research.

Setting: Private assisted reproduction center.

Simultaneous determination of unmodified sevoflurane and of its metabolite hexafluoroisopropanol in urine by headspace sorptive extraction-thermal desorption-capillary gas chromatography-mass spectrometry.

Unmodified sevoflurane and its metabolite, hexafluoroisopropanol (HFIP), have both been proposed as biomarkers of exposure in post-shift urine for operating room personnel exposed to inhalation anaesthetic sevoflurane. We used headspace sorptive extraction (HSSE) and thermal desorption-capillary GC-MS to assess sensitively both compounds in the urine matrix (after a HFIP deconjugation step). In GC-MS splitless mode, calibration plots (approximately 15-650 microg/L) were linear (r2 > 0.

High-speed capillary gas chromatography for determination of inhalation anesthetics.

To increase sample throughput for GC analysis of inhalation anaesthetics without affecting the separation of nitrous oxide (N2O) and halogenated anaesthetics (sevoflurane, isoflurane and halothane), we explored the effectiveness of a tailor-shortened (12 m) PlotQ capillary column and developed a high-speed version of a previously reported GC technique (involving chromatographic separation of analytes using a GC-MS system, coupled with a selected ion monitoring (SIM) method to increase sensitivity). Efficient separation and repeatable results were achieved at a reduced runtime of approximately 7 min (versus 18 min with the original method) at a carrier gas flow of 1.5 ml/min.

Urinary sevoflurane and hexafluoro-isopropanol as biomarkers of low-level occupational exposure to sevoflurane.

Objectives: Sevoflurane is an inhalation halogenated anaesthetic widely used in day and paediatric surgery. We were interested in evaluating biological markers of exposure to sevoflurane, which should improve the health surveillance of occupationally exposed personnel.

Methods: A group of 36 subjects (13 male, 23 female) occupationally exposed to volatile anaesthetics in paediatric operating rooms was studied in a 2-week survey.

Simultaneous determination of t,t-muconic, S-phenylmercapturic and S-benzylmercapturic acids in urine by a rapid and sensitive liquid chromatography/electrospray tandem mass spectrometry method.

We describe a rapid and sensitive high-performance liquid chromatography/electrospray tandem mass spectrometry (HPLC/ESI-MS/MS) method for simultaneous determination of the most relevant metabolites of benzene and toluene, t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (S-PMA), and S-benzylmercapturic acid (S-BMA). Urine samples were purified before analysis by solid-phase microextraction (SPE) on SAX cartridges with 50 mg sorbent mass. The developed method fulfils all the standard requirements of precision and accuracy.

Proposal for single and mixture biological exposure limits for sevoflurane and nitrous oxide at low occupational exposure levels.

Objectives: Assessment of individual exposures to sevoflurane plus nitrous oxide (N(2)O) by biological monitoring of unmodified analytes in post-shift urine of exposed personnel.

Methods: Anaesthetics in urine and breathing area were monitored in 124 subjects in 11 operating theatres. Passive samplers were collected after 2.

Lack of correlation between environmental or biological indicators of benzene exposure at parts per billion levels and micronuclei induction.

Despite growing concern for possible carcinogenic effects associated with environmental benzene exposure in the general population, few studies exist at parts per billion (ppb) levels. We investigated the existence of a relationship between airborne/biological measurements of benzene exposure (i.e.

Enflurane as an internal standard in monitoring halogenated volatile anaesthetics by headspace gas chromatography-mass spectrometry.

Recently. we proposed the use of a run-only headspace-GC-MS method for the biological monitoring of ppb concentrations of unmodified volatile anaesthetics (isoflurane, sevoflurane and halothane, plus nitrous oxide) in post-shift urine of operating theatre personnel. The adoption of enflurane (a volatile anaesthetic no longer used in clinical practice) as a poper and viable internal standard improves intra-day and inter-day accuracy in halide quantitation, providing a GC-MS reference method useful in the practice of biomonitoring of exposure of operating theatre personnel to modern volatile anaesthetics (isoflurane.

Lack of sensitivity of urinary trans,trans-muconic acid in determining low-level (ppb) benzene exposure in children.

Benzene is a widespread pollutant of which the main source in the outside environment is automotive traffic. Benzene is also present in cigarette smoke, and small quantities exist in drinking water and food; all of these sources contribute to pollution of indoor environments. Benzene exposure may be studied with biologic indicators.