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Objective: To analyze the atmosphere inside incubators regarding alcoholic solvent such as isopropanol or ethanol which are commonly used in hand disinfecting solutions. Design: Observational. Setting: The third level neonatal unit of the Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. Patients: Nine neonates with median (range) gestational age of 29 4/7 (25 5/7-39 0/7) weeks and birth weight of 960 (550-3050) grams. All neonates were inside incubators. Interventions: Alcoholic vapors inside incubators were directly and cumulatively measured by photoionisation and gas chromatography respectively after absorption on a charcoal sampling tube. Results: Eleven studies (mean study time: 230 ± 19 minutes) were performed. Highly variable isopropanol/ethanol concentrations profiles were found inside incubators. Peak value for isopropanol was 1982 part per million and for ethanol was 906 part per million. Conclusions: Incubators' inner atmosphere can be highly polluted by alcohol vapors. To reduce them staff should respect long evaporation time between hands disinfection and manipulations inside incubators. The use of an ethanol-based disinfecting solution, because of its short evaporation time, could be favored. As alcohol vapor toxicity for neonate remains largely unknown, further studies could be welcome. [ABSTRACT FROM AUTHOR]

Difference in exposure to chromium according to the type of electrolytic deposition was investigated in 12 workshops. Results of industrial hygiene surveys including air and urine analyses show that exposure is more important for hard than for bright chromium electroplating. [ABSTRACT FROM PUBLISHER]

Purpose: In Burkina Faso, gold ore is one of the main sources of income for an important part of the active population. Artisan gold miners use mercury in the extraction, a toxic metal whose human health risks are well known. The aim of the present study was to assess mercury exposure as well as to understand the exposure determinants of gold miners in Burkinabe small-scale mines., Methods: The examined gold miners' population on the different selected gold mining sites was composed by persons who were directly and indirectly related to gold mining activities. But measurement of urinary mercury was performed on workers most susceptible to be exposed to mercury. Thus, occupational exposure to mercury was evaluated among ninety-three workers belonging to eight different gold mining sites spread in six regions of Burkina Faso. Among others, work-related exposure determinants were taken into account for each person during urine sampling as for example amalgamating or heating mercury. All participants were medically examined by a local medical team in order to identify possible symptoms related to the toxic effect of mercury., Results: Mercury levels were high, showing that 69% of the measurements exceeded the ACGIH (American Conference of Industrial Hygienists) biological exposure indice (BEI) of 35 μg per g of creatinine (μg/g-Cr) (prior to shift) while 16% even exceeded 350 μg/g-Cr. Basically, unspecific but also specific symptoms related to mercury toxicity could be underlined among the persons who were directly related to gold mining activities. Only one-third among the studied subpopulation reported about less than three symptoms possibly associated to mercury exposure and nearly half of them suffered from at least five of these symptoms. Ore washers were more involved in the direct handling of mercury while gold dealers in the final gold recovery activities. These differences may explain the overexposure observed in gold dealers and indicate that the refining process is the major source of exposure., Conclusions: This study attests that mercury exposure still is an issue of concern. North-South collaborations should encourage knowledge exchange between developing and developed countries, for a cleaner artisanal gold mining process and thus for reducing human health and environmental hazards due to mercury use.

The aim of the study was to quantify the variability on biological indicators of exposure between men and women for three well known solvents: methyl ethyl ketone, 1-methoxy-2-propanol and 1,1,1-trichloroethane. Another purpose was to explore the effect of selected CYP2E1 polymorphisms on the toxicokinetic profile. Controlled human exposures were carried out in a 12 m³ exposure chamber for each solvent separately, during 6h and at half of the threshold limit value. The human volunteers groups were composed of ten young men and fifteen young women, including ten women using hormonal contraceptive. An analysis of variance mainly showed an effect on the urinary levels of several biomarkers of exposure among women due to the use of hormonal contraceptive, with an increase of more than 50% in metabolites concentrations and a decrease of up to 50% in unchanged substances concentrations, suggesting an increase in their metabolism rate. The results also showed a difference due to the genotype CYP2E1*6, when exposed to methyl ethyl ketone, with a tendency to increase CYP2E1 activity when volunteers were carriers of the mutant allele. Our study suggests that not only physiological differences between men and women but also differences due to sex hormones levels can have an impact on urinary concentrations of several biomarkers of exposure. The observed variability due to sex among biological exposure indices can lead to misinterpretation of biomonitoring results. This aspect should have its place in the approaches for setting limits of occupational exposure., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Agricultural workers are exposed to folpet, but biomonitoring data are limited. Phthalimide (PI), phthalamic acid (PAA), and phthalic acid (PA) are the ring metabolites of this fungicide according to animal studies, but they have not yet been measured in human urine as metabolites of folpet, only PA as a metabolite of phthalates. The objective of this study was thus to develop a reliable gas chromatography-tandem mass spectrometry (GC-MS) method to quantify the sum of PI, PAA, and PA ring-metabolites of folpet in human urine. Briefly, the method consisted of adding p-methylhippuric acid as an internal standard, performing an acid hydrolysis at 100 °C to convert ring-metabolites into PA, purifying samples by ethyl acetate extraction, and derivatizing with N,O-bis(trimethylsilyl)trifluoro acetamide prior to GC-MS analysis. The method had a detection limit of 60.2 nmol/L (10 ng/mL); it was found to be accurate (mean recovery, 97%), precise (inter- and intra-day percentage relative standard deviations <13%), and with a good linearity (R (2) > 0.98). Validation was conducted using unexposed peoples urine spiked at concentrations ranging from 4.0 to 16.1 μmol/L, along with urine samples of volunteers dosed with folpet, and of exposed workers. The method proved to be (1) suitable and accurate to determine the kinetic profile of PA equivalents in the urine of volunteers orally and dermally administered folpet and (2) relevant for the biomonitoring of exposure in workers.

Glycol ethers still continue to be a workplace hazard due to their important use on an industrial scale. Currently, chronic occupational exposures to low levels of xenobiotics become increasingly relevant. Thus, sensitive analytical methods for detecting biomarkers of exposure are of interest in the field of occupational exposure assessment. 1-Methoxy-2-propanol (1M2P) is one of the dominant glycol ethers and the unmetabolized urinary fraction has been identified to be a good biological indicator of exposure. An existing analytical method including a solid-phase extraction and derivatization before GC/FID analysis is available but presents some disadvantages. We present here an alternative method for the determination of urinary 1M2P based on the headspace gas chromatography technique. We determined the 1M2P values by the direct headspace method for 47 samples that had previously been assayed by the solid-phase extraction and derivatization gas chromatography procedure. An inter-method comparison based on a Bland-Altman analysis showed that both techniques can be used interchangeably. The alternative method showed a tenfold lower limit of detection (0.1 mg/L) as well as good accuracy and precision which were determined by several urinary 1M2P analyses carried out on a series of urine samples obtained from a human volunteer study. The within- and between-run precisions were generally about 10%, which corresponds to the usual injection variability. We observed that the differences between the results obtained with both methods are not clinically relevant in comparison to the current biological exposure index of urinary 1M2P. Accordingly, the headspace gas chromatography technique turned out to be a more sensitive, accurate, and simple method for the determination of urinary 1M2P.

The use of urinary hexane diamine (HDA) as a biomarker to assess human respiratory exposure to hexamethylene diisocyanate (HDI) aerosol was evaluated. Twenty-three auto body shop workers were exposed to HDI biuret aerosol for two hours using a closed exposure apparatus. HDI exposures were quantified using both a direct-reading instrument and a treated-filter method. Urine samples collected at baseline, immediately post exposure, and every four to five hours for up to 20 hours were analyzed for HDA using gas chromatography and mass spectrometry. Mean urinary HDA (microg/g creatinine) sharply increased from the baseline value of 0.7 to 18.1 immediately post exposure and decreased rapidly to 4.7, 1.9 and 1.1, respectively, at 4, 9, and 18 hours post exposure. Considerable individual variability was found. Urinary HDA can assess acute respiratory exposure to HDI aerosol, but may have limited use as a biomarker of exposure in the workplace.

Objective: The two isomers propylene glycol monomethyl ether [PGME-alpha (1-methoxy-2-propanol, M2P) and PGME-beta (2-methoxy-1-propanol)] have different toxicities due to the different ways they are metabolised. The higher toxicity of PGME-beta has been attributed to the formation of 2-methoxypropionic acid (2-MPA) as a metabolite of primary alcohol. Six healthy male volunteers were exposed to PGME-alpha vapour (15, 50 and 95 ppm) with and without respiratory protection for 6 h, including a 30-min break. They were also exposed to PGME-alpha liquid (10% or 30% in water), via one hand, for 30 min or 1 h. Commercial products of M2P always contain a small quantity of the beta isomer, and GC analysis has shown that the product used for this human volunteer exposure contained approximately 0.3% of the beta isomer. The objective of this study was to determine the levels of 2-MPA in urine after these exposures to 99.7% PGME-alpha., Method: An analytical method developed by Laitinen [6] was used for the determination of 2-MPA in the urine of exposed volunteers., Results: End exposure levels of 2-MPA were found to reach from 1.19 to 3.29 mg/l for inhalation and dermal exposure to PGME-alpha vapour and from under the detection limit to 2.10 mg/l for exposure of one hand in PGME-alpha liquid. 2-MPA concentrations in urine samples from a non-exposed person or from a person exposed to PGME-alpha vapour at 15 ppm (inhalation and dermal exposure) and also from a person exposed to PGME-alpha vapour up to 95 ppm with respiratory protection (dermal-only exposure) all varied from under the detection limit to 0.30 mg/l and are then not significant.

Objective: Propylene glycol monomethyl ether (PGME) is a widely used additive in industrial and consumer products (paints, inks, diluents, cleaning products, cosmetics.). The aim of the present study was to determine uptake and disposition of PGME alpha-isomer in humans., Method: Six healthy male volunteers were exposed to PGME-alpha vapour (15, 50 and 95 ppm) with and without respiratory protection for 6 h including a 30-min break. Free PGME and total PGME (free and conjugated) were analysed in urine. The analytical method involved hydrolysis with HCl (only for the analysis of total PGME in urine), a solid phase extraction on LC-18 columns and a gas chromatograph-flame ionisation detector (GC/FID) analysis after derivatisation with trimethylsilylimidazole., Results: End-exposure levels of free PGME in urine were found to reach 1.3 (+/-0.3), 4.4 (+/-1.6) and 7.9 (+/-2.5) mg/l for 15, 50 and 95-ppm exposure, respectively, without respiratory protection. End-exposure levels of total PGME in urine were found to reach 2.5 (+/-0.8), 6.2 (+/-1.6) and 10.3 (+/-2.3) mg/l for 15, 50 and 95-ppm exposure respectively. Levels of free PGME were also monitored in exhaled air (0.4 (+/-0.1), 1.4 (+/-0.4) and 2.9 (+/-0.9) ppm at the end of 15, 50 and 95-ppm exposure, respectively) and in blood (2.0 (+/-0.9), 4.9 (+/-2.3) and 11.8 (+/-2.4) mg/l at the end of 15, 50 and 95-ppm exposure, respectively). PGME is rapidly excreted in urine and in exhaled air; the half-lives were calculated to be approximately 3.5 h in urine and 10 min in exhaled air. PGME was below detection limits in breath (<0.1 ppm), in blood (<1 mg/l) and in urine (<1 mg/l) after dermal-only exposure to vapour., Conclusions: This study has demonstrated the relatively high pulmonary uptake compared with the dermal uptake. It has also shown the rapid excretion in urine (3.5 h) and in expired air (10 min). With regard to metabolism, this study has established the presence of conjugated PGME in urine.

Objective: The objective of this study was to determine the validity of tobacco questionnaires when using as gold standard either a single biomarker or a combination of two biomarkers., Methods: The methods were self-reported smoking compared with salivary thiocyanate and expired carbon monoxide in a 1996, population-based, Swiss survey of 552 men and 565 women., Results: Sensitivity of self-reported smoking relative to salivary thiocynate or carbon monoxide alone was low (38.2% for salivary thiocyanate > or = 100 mg/L, 56.4% for salivary thiocyanate > or = 150 mg/L and 62.6% for carbon monoxide > or = 9 ppm). When defining true positive smokers as people with high concentration of both salivary thiocyanate and carbon monoxide, overall, sensitivity was 88.6% and specificity was 87.2%. In women, sensitivity increased from 85 to 89% when removing subjects exposed to passive smoking. When excluding heavy smokers, sensitivity decreased to 63% in men and to 71% in women. Older women had tendency to misreport smoking., Conclusions: This comparison of questionnaire data with the simultaneous measurement of salivary thiocyanate and expired carbon monoxide indicates that valid responses can be obtained for self-reported, current smoking in population-based surveys. However, the validity of questionnaires can be underestimated if the gold standard (of exposure to tobacco smoke) is either high levels of carbon monoxide or high levels of salivary thiocyanate., (Copyright 2000 American Health Foundation and Academic Press.)

A young patient suffering from schizophrenia had intense headaches and photophobia which were induced by intra-ocular injections of mercury. The clinical diagnosis was established once foreign bodies were visualized on regular X-rays of the patients skull. The mercury intoxication in combination with the secondary irreversible lesions to the eyes necessitated a bilateral enucleation and the use of a chelating treatment with sodium-dimercapto-1-propane sulfate (DMP). Automutilation is a very rare and dramatic complication of schizophrenia. The psychiatric handling and meaning of such dramatic automutilation is discussed in this case report together with a recent review of the toxicologic treatment of mercury intoxication in humans.