| 1. |
- Anundi, Helena, et al.
(författare)
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Air and biological monitoring of solvent exposure during grafitti removal
- 2000
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 0340-0131 .- 1432-1246. ; 73:8, s. 561-569
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The principal aim of the study was to estimate the level of exposure to organic solvents of graffiti removers, and to identify the chemicals used in different cleaning agents. A secondary objective was to inform about the toxicity of various products and to optimise working procedures.METHODS: Exposure to organic solvents was determined by active air sampling and biological monitoring among 38 graffiti removers during an 8-h work shift in the Stockholm underground system. The air samples and biological samples were analysed by gas chromatography. Exposure to organic solvents was also assessed by a questionnaire and interviews.RESULTS: Solvents identified were N-methylpyrrolidone (NMP), dipropylene glycol monomethyl ether (DPGME), propylene glycol monomethyl ether (PGME), diethylene glycol monoethyl ether (DEGEE), toluene, xylene, pseudocumene, hemimellitine, mesitylene, ethylbenzene, limonene, nonane, decane, undecane, hexandecane and gamma-butyrolactone. The 8-h average exposures [time-weighted average (TWA)] were below 20% of the Swedish permissible exposure limit value (PEL) for all solvents identified. In poorly ventilated spaces, e.g. in elevators etc., the short-term exposures exceeded occasionally the Swedish short-term exposure limit values (STEL). The blood and urine concentrations of NMP and its metabolites were low. Glycol ethers and their metabolites (2-methoxypropionic acid (MPA), ethoxy acetic acid (EAA), butoxy acetic acid (BAA), and 2-(2-methoxyethoxy) acetic acid (MEAA)) were found in low concentrations in urine. There were significant correlation between the concentrations of NMP in air and levels of NMP and its metabolites in blood and urine. The use of personal protective equipment, i.e. gloves and respirators, was generally high.CONCLUSIONS: Many different cleaning agents were used. The average exposure to solvents was low, but some working tasks included relatively high short-term exposure. To prevent adverse health effects, it is important to inform workers about the health risks and to restrict the use of the most toxic chemicals. Furthermore, it is important to develop good working procedures and to encourage the use of personal protection equipment.
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| 2. |
- Carnerup, Martin, et al.
(författare)
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Determination of 5-hydroxy-N-methyl-2-pyrrolidone and 2-hydroxy-N-methylsuccinimide in human plasma and urine using liquid chromatography-electrospray tandem mass spectrometry
- 2001
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Ingår i: Journal of Chromatography. B. - 1387-2273. ; 761:1, s. 107-113
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Tidskriftsartikel (refereegranskat)abstract
- A method for simultaneous determination of 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI) was developed. These compounds are metabolites from N-methyl-2-pyrrolidone (NMP), a powerful and widely used organic solvent. 5-HNMP and 2-HMSI were purified from plasma and urine by solid-phase extraction using Isolute ENV+ columns, and analysed by liquid chromatography coupled to a mass spectrometer fitted with an atmospheric pressure turbo ion spray ionisation interface in the positive ion mode. The method was validated for plasma and urine concentrations from 0.12 to 25 microg/ml. The recoveries for 5-HNMP and 2-HMSI in plasma were 99 and 98%, respectively, and in urine 111 and 106%, respectively. For 5-HNMP and 2-HMSI, the within-day precision in plasma was 1-4 and 3-6%, respectively, and in urine 2-12 and 3-10%, respectively. The corresponding data for the between-day precision was 5 and 3-6%, respectively, and 4-6 and 7-8%, respectively. The detection limit for 5-HNMP was 4 ng/ml in plasma and 120 ng/ml in urine. For 2-HMSI, it was 5 ng/ml in plasma and 85 ng/ml in urine. The method is applicable for analysis of plasma and urine samples from workers exposed to NMP.
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| 3. |
- Jönsson, Bo A, et al.
(författare)
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Determination of 5-hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide in human urine
- 1997
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Ingår i: Journal of Chromatography. B. - 1387-2273. ; 694:2, s. 351-357
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Tidskriftsartikel (refereegranskat)abstract
- A method for simultaneous determination of 5-hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide in urine is described. These compounds are metabolites of N-methyl-2-pyrrolidone, a powerful and widely used organic solvent. 5-Hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide were purified from urine by adsorption to a C8 solid-phase extraction column and then elution by ethyl acetate-methanol (80:20). After evaporation, the samples were derivatised at 100 degrees C for 1 h by bis(trimethylsilyl)trifluoroacetamide. Ethyl acetate was then added and the samples were analysed by gas chromatography-mass spectrometry in the electron impact mode. The extraction recovery for 5-hydroxy-N-methylpyrrolidone was about 80% while that for 2-hydroxy-N-methylsuccinimide was about 30%. The intra-day precision for 5-hydroxy-N-methylpyrrolidone was 2-4% and the between-day precision 4-21% (4 and 60 microg/ml). The intra-day precision for 2-hydroxy-N-methylsuccinimide was 4-8% and the between-day precision 6-7% (2 and 20 microg/ml). The detection limit was 0.2 microg/ml urine for both compounds. The method is applicable for analysis of urine samples from workers exposed to N-methyl-2-pyrrolidone.
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| 4. |
- Jönsson, Bo A, et al.
(författare)
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Determination of N-methylsuccinimide and 2-hydroxy-N-methylsuccinimide in human urine and plasma
- 1997
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Ingår i: Journal of Chromatography. B. - 1387-2273. ; 704:1-2, s. 151-158
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Tidskriftsartikel (refereegranskat)abstract
- A method for determination of N-methylsuccinimide (MSI) and 2-hydroxy-N-methylsuccinimide (2-HMSI) in human urine and of MSI in human plasma was developed. MSI and 2-HMSI are metabolites of the widely used organic solvent N-methyl-2-pyrrolidone (NMP). MSI and 2-HMSI were purified from urine and plasma by C8 solid-phase extraction and analysed by gas chromatography-mass spectrometry in the negative-ion chemical ionisation mode. The intra-day precisions in urine were 2-6% for MSI (50 and 400 ng/ml) and 3-5% for 2-HMSI (1000 and 8000 ng/ml). For MSI in plasma it was 2% (60 and 1200 ng/ml). The between-day precisions in urine were 3-4% for MSI (100 and 1000 ng/ml) and 2-4% for 2-HMSI (10,000 and 18,000 ng/ml) and 3-4% for MSI in plasma (100 and 900 ng/ml). The recoveries from urine were 109-117% for MSI (50 and 400 ng/ml) and 81-89% for 2-HMSI (1000 and 8000 ng/ml). The recovery of MSI from plasma was 91-101% (50 and 500 ng/ml). The detection limits for MSI were 3 ng/ml in urine and 1 ng/ml in plasma and that of 2-HMSI in urine was 200 ng/ml. The method is applicable for analysis of urine and plasma samples from workers exposed to NMP.
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| 5. |
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| 6. |
- Jönsson, Bo A, et al.
(författare)
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N-methylsuccinimide in plasma and urine as a biomarker of exposure to N-methyl-2-pyrrolidone
- 2001
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Ingår i: International Archives of Occupational and Environmental Health. - 1432-1246. ; 74:4, s. 289-294
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: N-Methyl-2-pyrrolidone (NMP) is a selective and powerful organic solvent. The aim of this study was to investigate whether the NMP metabolite N-methylsuccinimide (MSI) in plasma and urine can be used as a biomarker of exposure to NMP. METHODS: Six healthy subjects were exposed to 10, 25, and 50 mg NMP/m3 in an exposure chamber for 8 h. The air levels were monitored by XAD-7 solid sorbent sampling, and analysed by gas chromatography (GC). Plasma and urine were sampled for two days following the exposure, and the levels of MSI were analysed by GC with mass spectrometric detection. RESULTS: The concentration of MSI in plasma and urine rose during the exposure, and reached a peak at about 4 h after the end of the exposure. The concentration then decayed according to a one-compartment model with a half-time of approximately 8 h. About 1% of the inhaled NMP was excreted in urine as MSI. There were very close correlations between the NMP air levels and, on the one hand, the MSI concentrations in plasma collected at the end of exposure (r = 0.98), or the urinary MSI concentration collected during the last 2 h of exposure (r = 0.96), on the other. CONCLUSIONS: MSI in plasma or urine is applicable as a biomarker of exposure to NMP. The concentration in plasma and urine mainly reflects the exposure over one day.
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| 7. |
- Ståhlbom, Bengt, et al.
(författare)
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Experimental human exposure to N,N-dimethylbenzylamine: generation of a controlled atmosphere and biological monitoring
- 1997
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 1432-1246 .- 0340-0131. ; 70:6, s. 393-398
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to develop a method for generation of dimethylbenzylamine (DMBA) atmospheres in an exposure chamber and to investigate the possibility of using urinary DMBA metabolites for biological monitoring of exposure to DMBA. A DMBA atmosphere was generated by use of the gas-permeation principle. Six healthy male volunteers were exposed for 8 h to DMBA at air levels of 20, 45, and 80 μm/m3. Air levels of DMBA were analyzed by gas chromatography (GC). The total urinary amount of DMBA (U-SumDMBA; DMBA and metabolites that can be reduced to DMBA, e.g., DMBAO) was analyzed using GC-mass spectrometry (MS). The exposure chamber maintained very low (0–130 μg/m3) and steady concentrations for several weeks. DMBA uptake by inhalation was 76%. The amine was quickly distributed and biotransformed to nearly 100%. DMBA was eliminated in the urine with a half-time of 4.3 h. More than 50% was eliminated within 2 h of exposure. However, at all exposure levels the subjects continued to excrete DMBA the next morning. There was a significant correlation between the exposure to DMBA and the U-SumDMBA. Thus, U-SumDMBA may become an important biomarker for monitoring of industrial exposure to DMBA.
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| 8. |
- Åkesson, Bengt, et al.
(författare)
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Biological monitoring of N-methyl-2-pyrrolidone using 5-hydroxy-N-methyl-2-pyrrolidone in plasma and urine as the biomarker
- 2000
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Ingår i: Scandinavian Journal of Work, Environment and Health. - 0355-3140. ; 26:3, s. 213-218
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: The aims were to study the toxicokinetics of 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) in blood and urine after exposure to N-methyl-2-pyrrolidone (NMP) and to study the suitability of 5-HNMP as a biomarker for assessing NMP exposure. METHODS: Six male volunteers were exposed for 8 hours to NMP concentrations of 0, 10, 25, and 50 mg/m3. Blood and urine were sampled before, during, and up to 40 hours after exposure. Aliquots of urine and plasma were purified, derivatized, and analyzed for 5-HNMP on a gas chromatograph/mass spectrometer in the electron impact mode. RESULTS: The mean plasma concentration [P-(5-HNMP)] after 8-hour NMP exposure to 10, 25, and 50 mg/m3 was 8.0, 19.6, and 44.4 micromol/l, respectively. The mean urinary concentration [U-(5-HNMP)] for the 2 last hours of exposure was 17.7, 57.3, and 117.3 mmol/mol creatinine, respectively. The maximal P-(5-HNMP)and U-(5-HNMP) concentrations occurred 1 hour and 0-2 hours, respectively, after the exposure. The half-times of P-(5-HNMP) and U-(5-HNMP) were 6.3 and 7.3 hours, respectively. The 5-HNMP urinary concentrations were 58% of the calculated retained dose. There was a close correlation (r) between P-(5-HNMP) (r=0.98) and U-(5-HNMP) (r=0.97) with NMP exposure. CONCLUSIONS: 5-HNMP is an excellent biomarker for assessing exposure to NMP. Its plasma and urinary half-times (6-7 hours), the minimal risk for contamination during sampling in occupational settings, and the close correlation of P-(5-HNMP) and U-(5-HNMP) with NMP exposure makes 5-HNMP suitable for monitoring exposure to NMP. 5-HNMP in plasma is recommended.
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| 9. |
- Åkesson, Bengt, et al.
(författare)
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Evaluation of exposure biomarkers from percutaneous absorption of N-methyl-2-pyrrolidone.
- 2004
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Ingår i: Scandinavian Journal of Work, Environment and Health. - 0355-3140. ; 30:4, s. 306-312
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: The aim of this study was to evaluate different biomarkers of exposure to N-methyl-2-pyrrolidone (NMP), a widely used industrial chemical. For this purpose, differences in toxicokinetics between men and women and between pure and water-mixed NMP were evaluated after dermal absorption. METHODS: Six female and six male volunteers (groups 1 and 2) were topically exposed for 6 hours to 300 mg of NMP. An additional group of six male volunteers (group 3) was exposed to 300 mg of NMP in a 50% water solution. Blood and urine were sampled before, during, and up to 9 days after the exposure. Plasma and urine were analyzed using mass spectrometry. RESULTS: For groups 1 and 2, 16% and 18% of the applied dose were recovered in the urine as the sum of NMP and its metabolites. For group 3, 4% was recovered. The maximal concentration of 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) was 10, 8.1, and 2.1 micromol/l for groups 1, 2 and 3, respectively, in plasma and 420, 360 and 62 micromol/l in urine adjusted for density. For 2-hydroxy-N-methylsuccinimide (2-HMSI), the maximal concentration was 5.4, 4.5, and 1.3 micromol/l for groups 1, 2 and 3, in plasma, respectively, and 110, 82 and 19 micromol/l in urine adjusted for density. For 5-HNMP there was a difference in time to reach the maximal concentration depending on whether pure NMP or 50% NMP in water was used. No such difference was seen for 2-HMSI. The differences in kinetics between male and female volunteers were small. CONCLUSIONS: Preferably 2-HMSI should be used as the biomarker of exposure to NMP.
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| 10. |
- Åkesson, Bengt, et al.
(författare)
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Major metabolic pathway for N-methyl-2-pyrrolidone in humans
- 1997
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Ingår i: Drug Metabolism and Disposition. - 1521-009X. ; 25:2, s. 267-269
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to study the metabolic pathway for N-methyl-2-pyrrolidone (NMP) in humans. Three healthy male volunteers were administered 100 mg NMP orally. All urine was collected during nine consecutive days. The identification and quantification of the metabolites were performed by gas chromatography/mass spectrometry (GC/MS). NMP, 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP), N-methylsuccinimide (MSI), and 2-hydroxy-N-methylsuccinimide (2-HMSI) were found in urine. The mean excreted fractions for NMP, 5-HNMP, MSI, and 2-HMSI were 0.8%, 44%, 0.4%, and 20%, respectively. There was no conjugation with glucoronic acid or sulfate or either 5-HNMP or 2-HMSI. One-third of the orally dosed NMP was not recovered in urine as either NMP, 5-HNMP, MSI, or 2-HMSI. The half-lives for 5-HNMP, MSI, and 2-HMSI in urine were approximately 4, 8, and 17 hr, respectively.
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