Toxicology Commons^™

Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry Quantitation Of O-Cresol In Hydrolyzed Human Urine To Assess Toluene Exposure, Eric Langlois, Sébastien Gagné

Études primaires

Rationale

Toluene is a volatile organic compound used in domestic and industrial applications. The main routes of workplace exposure to toluene are inhalation and dermal contact. As toluene exposure can cause severe nervous system damage, its quantification is crucial to prevent occupational illness. Toluene is metabolized mainly as hippuric acid, S-benzylmercapturic acid and epoxides. These are rapidly converted to o-/p-cresol, which is then excreted in the urine as conjugated glucuronides and sulfates. o-Cresol and its conjugates can be chemically hydrolyzed to form free o-cresol, which can then serve as a urinary biomarker of toluene exposure. Current …

Development And Characterization Of An Adaptable Aerosolized Methylene Diphenyl Diisocyanate Generation System, Simon Aubin, Loïc Wingert, Sébastien Gagné, Livain Breau, Jacques Lesage

Études primaires

Reactive semivolatile contaminants, such as isocyanates, can be particularly difficult to assess in occupational environments. While standard methods exist for isocyanates, there are still significant differences between the results they provide for various occupational environments or processes. This study presents the validation of a laboratory system for the generation of controlled atmospheres of isocyanates. A system consisting of different modules generated airborne methylene diphenyl diisocyanate (MDI) by nebulizing a solution into mixing and exposure chambers with control of flow rate, temperature, and relative humidity. Sampling was performed through an eight-port flow splitter that allowed only very slight within-test variability. MDI …

Occupational Exposure To Antineoplastic Drugs: What About Hospital Sanitation Personnel?, France Labrèche, Capucine Ouellet, Brigitte Roberge, Nicolas J Caron, Ahmed Yennek, Jean-François Bussières

Études primaires

Objective

Occupational exposure to antineoplastic drugs (ANPs) occurs mainly through dermal contact. Our study was set up to assess the potential exposure of hospital sanitation (HS) personnel, for whom almost no data are available, through contamination of surfaces they regularly touch.

Methods

In the oncology departments of two hospitals around Montreal, surface wipe samples of 120–2000 cm² were taken at 10 sites cleaned by the HS personnel and five other sites frequently touched by nursing and pharmacy personnel. A few hand wipe samples were collected to explore skin contamination. Wipes were analyzed by ultra-performance liquid chromatography tandem–mass spectrometry for …

On Site Comparison Of The Osha 42, Asset Ez4-Nco, Iso-Chek, Dan And Cip10 Methods For Measuring Toluene Diisocyanate (Tdi) At A Polyurethane Foam Factory, Simon Aubin, El Mekki Hamdi, Audrey Joly, Philippe Sarazin, Jacques Lesage, Livain Breau, Mark Spence, Sébastien Gagné

Études primaires

Because of the semi-volatile nature of diisocyanates (being airborne in both physical vapor and particulate phases), their high reactivity and low occupational exposure limits, diisocyanate exposure evaluation has been challenging for industrial hygienists and laboratories. The objective of this study was to compare the toluene diisocyanate (2,4 and 2,6 isomers, TDI) concentration measured by five methods in a flexible polyurethane foam factory using different collection or derivatization approaches. The methods used were: OSHA 42 modified (filter, 1-(2-pyridyl)piperazine) (OSHA), Asset EZ4-NCO (denuder and filter, dibutylamine) (Asset), Iso-Chek (double-filter, 9-(N-methylaminomethyl) anthracene and 1,2-methoxyphenylpiperazine), DAN (filter, 1,8-diaminonaphthalene), and CIP10 (centrifugation, 1,2-methoxyphenylpiperazine). Particle real-time …

On-Site Comparison Of The Osha 47, Asset Ez4-Nco, Iso-Chek, Dan, And Cip10 Methods For Measuring Methylene Diphenyl Diisocyanate (Mdi) At An Oriented-Strand Board (Osb) Factory, Simon Aubin, El Mekki Hamdi, Audrey Joly, Philippe Sarazin, Jacques Lesage, Livain Breau, Mark Spence, Sébastien Gagné

Études primaires

Diisocyanates are occupational contaminants and known sensitizers causing irritation (skin and respiratory tract) as well as occupational asthma. Because of their physicochemical properties (semi-volatile and high reactivity) and low occupational limits, diisocyanate exposure evaluation is still a challenge nowadays for industrial hygienists and laboratories. The objective of this study was to compare the methylene diphenyl diisocyanate (MDI) concentrations measured by five methods using different collection or derivatization approaches in an oriented-strand board (OSB) factory. The methods used were: OSHA 47 (filter, 1-(2-pyridyl)piperazine) (OSHA), Asset EZ4-NCO (denuder and filter, dibutylamine) (Asset), Iso-Chek (double-filter, 9-(N-methylaminomethyl) anthracene and 1,2-methoxyphenylpiperazine), DAN (filter, 1,8-diaminonaphthalene), and …

Halogenated Flame Retardants And Organophosphate Esters In The Air Of Electronic Waste Recycling Facilities: Evidence Of High Concentrations And Multiple Exposures, Sabrina Gravel, Jérôme Lavoué, Bouchra Bakhiyi, Miriam L. Diamond, Liisa M. Jantunen, Jacques Lavoie, Brigitte Roberge, Marc-André Verner, Joseph Zayed, France Labrèche

Études primaires

Background

In response to a worldwide increase in production of electronic waste, the e-recycling industry is rapidly rowing. E-recycling workers are exposed to many potentially toxic contaminants, among which flame retardants (FRs), mainly suspected of being endocrine disruptors, are thought to be the most prevalent.

Objective

To conduct an exposure assessment of four chemical groups of FRs in Canadian e-recycling facilities, and to identify the main cofactors of exposure.

Methods

Personal air samples were collected over a workday for 85 workers in six e-recycling facilities, grouped into three facility sizes, and for 15 workers in control commercial waste facilities. Total …

Identification Of Methylene Diphenyl Diisocyanate Thermal Degradation Products In A Generation Chamber By Liquid Chromatography Coupled With Tandem Mass Spectrometry, Sébastien Gagné, Yves Cloutier

Études primaires

Isocyanate thermal degradation characterization by liquid chromatography coupled with electrospray tandem mass spectrometry has been performed to elucidate the methylene diphenyl diisocyanate (MDI) thermal degradation structure emitted in a generation chamber using a temperature between 50°C and 180°C to produce MDI vapors. [M+H]⁺ ions containing an isocyanate functional group were studied by tandem mass spectrometry. The [M+H]⁺ ion analyses based on the combination of full scans and precursor ion scans were useful for identifying all structures. The compounds emitted were identified and validated as a mixture of compounds containing amine and isocyanate functions. Residual MDI, methylene diphenyl amino-isocyanate, …

Implementation And Evaluation Of An Analytical Method For A Novel Derivatizing Agent To Measure 4,4'-Methylene Diphenyl Diisocyanate Atmospheres, Silvia Puscasu, Simon Aubin, Mark Spence, Sébastien Gagné

Études primaires

Accurate measurement of 4,4'-methylene diphenyl diisocyanate (MDI) atmospheres is a challenge since the molecule is both chemically reactive and likely to be present in aerosol form when heated and sprayed because of its low vapor pressure. Meeting this challenge requires optimizing both the sampling device used and the derivatization agent employed to stabilize the isocyanate functional group. This study describes the use of a novel derivatization reagent for isocyanate sampling to address the challenge of MDI aerosol exposure sampling. Like most conventional derivatizing agents for isocyanates, 1,8-diaminonapthalene (DAN) reacts with isocyanate functional groups to form a urea. However, unlike other …

Cip10 Optimization For 4,4-Methylene Diphenyl Diisocyanate Aerosol Sampling And Field Comparison With Impinger Method, Silvia Puscasu, Simon Aubin, Yves Cloutier, Philippe Sarazin, Huu Van Tra, Sébastien Gagné

Études primaires

4,4-methylene diphenyl diisocyanate (MDI) aerosol exposure evaluation in spray foam insulation application is known as being a challenge because the spray foam application actually involves a fast-curing process. Available techniques are either not user-friendly or are inaccurate or not validated for this application. To address these issues, a new approach using a CIP10M was developed to appropriately collect MDI aerosol in spray foam insulation while being suitable for personal sampling. The CIP10M is a commercially available personal aerosol sampler that has been validated for the collection of microbial spores into a liquid medium. Tributylphosphate with 1-(2-methoxyphenyl)piperazine (MOPIP) was introduced into …

Comparison Between The Asset Ez4 Nco And Impinger Sampling Devices For Aerosol Sampling Of 4,4′-Methylene Diphenyl Diisocyanate In Spray Foam Application, Silvia Puscasu, Simon Aubin, Yves Cloutier, Philippe Sarazin, Huu Van Tra, Sébastien Gagné

Études primaires

4,4′-methylene diphenyl diisocyanate (MDI) aerosol exposure evaluation in spray foam insulation application is known to be a challenge. Current available techniques are either not user-friendly or are inaccurate or are not validated for this application. A new sampler has recently been developed to address the user-friendliness issues with other samplers: the ASSET EZ4-NCO, but the use of this sampler in spray foam insulation applications has not been demonstrated or validated. Because of this, the current work was undertaken to provide a comparison of the ASSET sampler with an impinger method, considered to be the best available method in the context …