[Study on the constituents of essential oil of Shunaoxin dropping pills by GC-MS].

OBJECTIVE: To study the constituents of essential oil from Shunaoxin dropping pills by GC-MS. METHODS: The essential oil from Shunaoxin dropping pills were extracted by absolute alcohol and analyzed by GC-MS. RESULTS: 15 components from the essential oil of Shunaoxin dropping pills were identified. CONCLUSION: The main components in the essential oil of Shunaoxin dropping pills are lactones such as Z-ligustilide, senkyunolide A,3-butylphthalide and 3-butylidenephthalide, other components are organic acids such as ethyl linoleate, 9,12-octadecadienoic acid and ethyl palmitate.

Bioactivity-guided fractionation of the volatile oil of Angelica sinensis radix designed to preserve the synergistic effects of the mixture followed by identification of the active principles.

In natural product research, it is a common experience that fractionation of biologically-active crude extracts can lead to the loss of their original activity. This is attributed to synergistic effects, where two or more components are required to be present together for full activity of the sample. Our previous study showed that a volatile oil of Angelica sinensis radix (VOAS) inhibited endothelial cell proliferation in culture. Here we have used a bioactivity-guided fractionation method to preserve any synergistic effects of VOAS combining countercurrent chromatography (CCC), the MTS cell viability assay and gas chromatography (GC). Using a two-phase CCC solvent system (heptane-ethyl acetate-methanol-water at a volume ratio of 27:23:27:23%), forty-five fractions were isolated, nine of which exhibited anti-endothelial properties. GC analysis showed two bioactive alkylphthalides, Z-ligustilide and n-butylidenephthalide (BP) were the major compounds detected in the bioactive fractions, and were absent in non-bioactive fractions. Our results indicate that Z-ligustilide and BP are the main constituents responsible for the anti-endothelial properties of VOAS. This rapid and reliable approach in preserving sample activity while isolating and identifying its active compounds suggests that this protocol can be a powerful tool for drug discovery from natural products.

[Study on the dynamic variations of Z-ligustilide and n-butylidenephthalide content in essential oil of radix angelicae sinensis from different growth period].

OBJECTIVE: To study the variation of the biomass of the root and active components of Angelica sinensis during different growth periods. METHODS: 27 batches of Angelica sinensis were harvested from different growth periods, and the biomass of underground parts were determined; The Gas Chromatography-Mass Spectrometry (GC-MS) was used for determining the contents of Z-ligustilide and n-Butylidenephthalide in essential oil of Radix Angelicae Sinensis. RESULTS: The average contents of n-Butylidenephthalide and Z-ligustilide were more than 1% and 40% in the total essential oil of Radix Angelicae sinensis respectively. Their contents showed larger difference during different growth period. CONCLUSION: The contents of Z-ligustilide and n-Butylidenephthalide of Radix Angelicae Sinensis is closely related to their growth period.

Perfluorosulfonic acid membrane catalysts for optical sensing of anhydrides in the gas phase.

Continuous, on-site monitoring of personal exposure levels to occupational chemical hazards in ambient air is a long-standing analytical challenge. Such monitoring is required to institute appropriate health measures but is often limited by the time delays associated with batch air sampling and the need for off-site instrumental analyses. In this work, we report on the first attempt to use the catalytic properties of perfluorosulfonic acid (PSA) membranes to obtain a rapid, selective, and highly sensitive optical response to trimellitic anhydride (TMA) in the gas phase for portable sensor device application. TMA is used as starting material for various organic products and is recognized to be an extremely toxic agent by the National Institute for Occupational Safety and Health (NIOSH). Resorcinol dye is shown to become immobilized in PSA membranes and diffusionally constrain an orange brown product that results from acid-catalyzed reaction with more rapidly diffusing TMA molecules. FTIR, UV/vis, reaction selectivity to TMA versus trimellitic acid (TMLA), and homogeneous synthesis are used to infer 5,7- dihydroxyanthraquinone-2-carboxylic acid as the acylation product of the reaction. The color response has a sensitivity to at least 3 parts per billion (ppb) TMA exposure and, in addition to TMLA, excludes maleic anhydride (MA) and phthalic anhydride (PA). Solvent extraction at long times is used to determine that the resorcinol extinction coefficient in 1100 EW PSA membrane has a value of 1210 m(2)/g at 271.01 nm versus a value of 2010 m(2)/g at 275.22 nm in 50 vol% ethanol/water solution. The hypsochromic wavelength shift and reduced extinction coefficient suggest that the polar perfluorosulfonic acid groups in the membrane provide the thermodynamic driving force for diffusion and immobilization. At a resorcinol concentration of 0.376 g/L in the membrane, a partition coefficient of nearly unity is obtained between the membrane and solution concentrations and a maximum conversion rate of one ambient TMA molecule for every two membrane-immobilized resorcinol molecules is observed in 15 min.

Allergic contact dermatitis to copolymers in cosmetics--case report and review of the literature.

Copolymers or heteropolymers are large molecules with high molecular weights (>1000 D). They have been underestimated for a long time as to their sensitizing capacities. Allergic contact dermatitis to 6 copolymers in cosmetics and 1 in a medical dressing has been described; however, the nature of the hapten is still unknown. We report a case of allergic contact dermatitis to polyvinylpyrrolidone (PVP)/hexadecene copolymer in a purple-colored lipstick and review the literature on allergic contact dermatitis to 7 copolymers: PVP/hexadecene, PVP/eicosene, PVP/1-triacontene, methoxy polyethyleneglycol (PEG)-22/dodecyl glycols, methoxy PEG-17/dodecyl glycols, phthalic anhydride/trimellitic anhydride/glycols, and polyvinyl methyl/maleic acid anhydride.

Exposure to hexahydrophthalic and methylhexahydrophthalic anhydrides--dose-response for sensitization and airway effects.

OBJECTIVES: This study clarified the exposure-response relationships for the organic acid anhydrides (OAA) hexahydrophthalic (HHPA) and methylhexahydrophthalic (MHHPA) anhydrides and the development of specific immunoglobulin (IG) E and G antibodies and work-related symptoms. METHODS: In an epoxy resin-using factory, air levels of OAA were determined by gas chromatography-mass spectrometry. Occupational, smoking, and medical histories (questionnaire) were obtained for 154 exposed workers and 57 referents. Work-related symptoms of the eyes and airways were recorded, and OAA metabolites were analyzed in urine. A skin-prick test with common allergens and conjugates of OAA were performed. Specific IgE (radioallergosorbent test) and IgG (enzyme-linked immumosorbent assay) antibodies were determined in serum, and spirometry was performed. RESULTS: Air levels of the OAA were low (HHPA < 1 to 94, MHHPA < 3 to 77 microg/m3) and associated with the concentrations of the OAA metabolites in urine. Furthermore, for the exposed workers, there were high prevalences of sensitization (IgE 22%, IgG 21%), which correlated with the exposure. Neither atopy nor smoking increased this risk significantly. Furthermore, work-related symptoms were more prevalent among the exposed workers than among the referents (eyes 23% versus 14%, nose 28% versus 16%, nose bleeding 8% versus 0%, lower airways 10% versus 4%), and they were related to the exposure (adjusted prevalence odds ratios (POR) in the highest group 7.7, 3.6 and 17, respectively) and the IgE levels (POR 4.9, 3.1 and 5.6, respectively). CONCLUSIONS: In spite of the very low OAA levels in the air and metabolites in the urine, there were high and exposure-related risks of specific IgE and IgG sensitization and of work-related symptoms for the eyes, nose (especially bleeding), and lower airways.

Determination of methyltetrahydrophthalic anhydride in air using gas chromatography with electron-capture detection.

Methyltetrahydrophthalic anhydride (MTHPA) stimulates the production of specific IgE antibodies which can cause occupational allergy even at extremely low levels of exposure (15-22 micrograms/m3). Safe use in industry demands control of the levels of exposure causing allergic diseases. Thus, the air monitoring of MTHPA is very important, and sensitive methods are required to measure low air concentrations or short-time peak exposures. This paper outlines the use of silica-gel tubes for sampling airborne MTHPA vapour, followed by analysis using gas chromatography with electron-capture detection. No breakthrough was observed at 113, 217, 673 and 830 micrograms/m3 (sampling volume 30, 60, 60 and 20 l, respectively; relative humidity 40-55%). Concentrations > 1.0 microgram/m3 could be quantified at 20-min sampling with a sampling rate of 1 l/min. The present method can also be applied to measurements of exposure to hexahydrophthalic and methylhexahydrophthalic anhydride. The risk of MTHPA exposure in two condenser plants was also assessed by determining MTHPA levels in air of the workplace. In conclusion, our method was found to be reliable and sensitive, and can be applied to the evaluation of MTHPA exposure.

Risk factors for sensitisation to methyltetrahydrophthalic anhydride.

OBJECTIVES: To examine an association between specific IgE to methyltetrahydrophthalic anhydride (MTHPA) and exposure time, atopic history, smoking habits, and total IgE concentrations. METHODS: A cross sectional survey was carried out on a population of 148 workers from two condenser plants using epoxy resin with MTHPA, an acid anhydride curing agent known to cause allergy. RESULTS: Using a Pharmacia CAP system with a MTHPA human serum albumin conjugate, specific IgE antibody was detected in serum from 97 (66%) out of the 148 workers exposed to MTHPA. Stepwise multiple linear regression analysis showed a striking relation between log concentrations of specific and total IgE (P < 0.0001). Furthermore, when the workers were divided into two groups according to a cut-off point (100 IU/ml) between low and high total IgE, current smoking was significantly (P = 0.025) associated with specific IgE production only in the group with low total IgE (< 100 IU/ml). CONCLUSIONS: Smoking is the most significant risk factor for raising specific IgE to MTHPA in the group with low total IgE concentrations.

Exposure-response relationships in the formation of specific antibodies to hexahydrophthalic anhydride in exposed workers.

OBJECTIVES: Exposure-response relationships in the formation of specific antibodies to hexahydrophthalic anhydride (HHPA) was studied in exposed workers. METHODS: The relation between exposure to HHPA and the levels of specific immunoglobin E [(radioallergosorbent test (RAST)] and immunoglobin G (enzyme-linked immunosorbent assay) antibodies was investigated in a cross-sectional study on 95 workers from two plants using epoxy resin with HHPA as a hardener; the mean time of exposure was 7 (range 0.1-25) years. RESULTS: The specific immunoglobin E and immunoglobin G was significantly increased in exposed workers when they were compared with unexposed workers or external referents. There was no significant difference in the number of RAST positives [N = 23 (24%)] between the groups of workers exposed to < 10 micrograms.m-3, 10--< 50 micrograms.m-3, or > or = 50 micrograms.m-3. No effects were found of atopy or smoking habits on the prevalence of RAST positives. Five out of seven workers positive for immunoglobulin E in the group with the lowest exposures reported frequent short-time (minutes per day) exposures exceeding 50 micrograms.m-3. A correlation was seen between specific immunoglobulin E and G antibodies (rs = 0.5). CONCLUSIONS: The results indicate that HHPA is a sensitizing compound even at low exposure levels and that short-time peak exposures may have an impact on immunoglobulin E sensitization.

Occupational exposure to hexahydrophthalic anhydride: air analysis, percutaneous absorption, and biological monitoring.

Urinary hexahydrophthalic acid (HHP acid) levels were determined in 20 workers occupationally exposed to hexahydrophthalic anhydride (HHPA) air levels of 11-220 micrograms/m3. The levels of HHP acid in urine increased rapidly during exposure and the decreases were also rapid after the end of exposure. The elimination half-time of HHP acid was 5 h, which was significantly longer than in experimentally exposed volunteers, possibly indicating distribution to more than one compartment. There was a close correlation between time-weighted average levels of HHPA in air and creatinine-adjusted levels of HHP acid in urine collected during the last 4 h of exposure (r = 0.90), indicating that determination of urinary HHP acid levels is suitable as a method for biological monitoring of HHPA exposure. An air level of 100 micrograms/m3 corresponded to a postshift urinary HHP acid level of ca. 900 nmol/mmol creatinine in subjects performing light work for 8 h. Percutaneous absorption of HHPA was studied by application of HHPA in petrolatum to the back skin of three volunteers. The excreted amounts of HHP acid in urine, as a fraction of the totally applied amount of HHPA, were within intervals of 1.4%-4.5%, 0.2%-1.3%, and 0%-0.4% respectively, indicating that the contribution from percutaneous absorption is of minor importance in a method for biological monitoring.

Localization of inhaled trimellitic anhydride to lung with a respiratory lymph node antibody secreting cell response.

Male Sprague-Dawley rats were exposed to trimellitic anhydride (TMA) by inhalation (500 micrograms/m3), 4 hours a day, for 1 to 10 days. TMA was localized to lung cells by immunoelectron microscopy. Enzyme-linked immunosorbent assay (ELISA) and Western blot analysis were used in an attempt to localize TMA to lung lavage proteins. The lung-associated lymph node (LALN) B-lymphocyte response was measured by quantitation of immunoglobulin (Ig)G, IgA, and IgM antibody secreting cells specific for TMA rat serum albumin (TM-RSA) by use of the enzyme-linked immunospot assay (ELISPOT) method. The IgG, IgM, and IgA antibody response to TM-RSA in serum and lavage fluid was quantitated by ELISA. Lung injury was assessed by the number of external lung hemorrhagic foci and lung weight. Immunoelectron microscopy localized TMA to alveolar and bronchial cells on all exposure days. ELISA detected trace amounts of TMA haptenized lavage proteins that could not be detected by Western blot analysis. A marked increase occurred in lung injury from day 7 to 10. The LALN IgG, IgA, and IgM antibody secreting cell response to TM-RSA paralleled measures of lung injury. IgG, IgM, and IgA serum and lavage antibody to TM-RSA were correlated with lung injury measures. Lavage and serum IgG antibody levels had the highest correlation with lung injury.

Determination of 4-methyl-cis-hexahydrophthalic anhydride in human blood by gas chromatography with electron-capture detection.

A gas-chromatographic technique using 63Ni electron-capture detection was applied to the determination of 4-methyl-cis-hexahydrophthalic anhydride in the blood of workers occupationally exposed to this airborne agent. The detection limit was 0.24 nmol ml-1. For occupational exposure to between 0.14 and 0.31 mg m-3 of the anhydride, the anhydride concentration in the workers' blood samples ranged from 3.4 to 10.7 nmol ml-1. The results are consistent with earlier findings in animal exposure experiments and support the view that the hydrolysis of the anhydride in a biological medium is not spontaneous, but might be an enzyme-catalysed reaction. The resulting dicarboxylic acid is excreted by the kidneys without further conjugation reactions.

Determination of hexahydrophthalic anhydride in air using gas chromatography.

Two methods for the determination of hexahydrophthalic anhydride (HHPA) in air were developed. In a solid sorbent method, HHPA was sampled in Amberlite XAD-2 tubes, eluted in toluene and analysed by gas chromatography with flame ionization detection. The sampling rates were 0.2 and 1.0 l/min. At 15 micrograms/m3 (relative humidity less than 2%) and 27 micrograms/m3 (relative humidity 70%) no breakthrough was observed. However, at 160 micrograms/m3 (relative humidity less than 2%), 6% breakthrough was found. The sampling efficiency of the sampling rates 0.2 and 1.0 l/min did not differ. In a bubbler method, HHPA was sampled in bubblers filled with 0.1 M sodium hydroxide solution. The sodium salt of hexahydrophthalic acid was formed. No breakthrough was observed using a sampling rate of 1.0 l/min. The samples were stable during storage for eight weeks in a refrigerator. The HHP acid was esterified with methanol-boron trifluoride and analysed by gas chromatography-flame ionization detection. Apparatus for the generation of standard atmospheres of HHPA, in the range of 10-3000 micrograms/m3, was developed using the diffusion principle. For the solid sorbent method the precision (coefficient of variation) of the overall method was 2-7%, and for the bubbler method 3-19% (range 15-160 micrograms HHPA/m3; relative humidity = less than 2-70%). A comparison between the two methods was performed using the standard atmosphere. The concentrations found by the solid sorbent method were 86-98% of those found by the bubbler method (range 15-160 micrograms HHPA per m3; relative humidity = less than 2-70%). In work environment air, 93% was found using the solid sorbent method relative to the bubbler method at a mean concentration of 330 micrograms/m3 (coefficient of variation = 39%; range 200-540 micrograms/m3). For both methods, concentrations greater than 3 micrograms/m3 could be quantified at 60 min sampling with a sampling rate of 1.0 l/min.

Urine phthalate determinations as an index of occupational exposure to phthalic anhydride and di(2-ethylhexyl)phthalate.

Although it has been estimated that over 600 000 workers in the United States are exposed to di(2-ethylhexyl)phthalate (DEHP), an animal carcinogen, and that over 100 000 are exposed to phthalic anhydride (PA), few data are available on levels of phthalates in biological fluids of these workers. For a determination of occupational exposure to PA and DEHP at a plant manufacturing DEHP from PA and 2-ethylhexanol, air samples were taken for PA and DEHP, and pre- and postshift urine samples were collected for the determination of total phthalates. Urine samples were obtained from 48 workers in jobs with high exposure to phthalates and from 47 workers in jobs with low exposure. The airborne concentrations of DEHP ranged from 20 to 4 110 micrograms/m3, and the concentrations of PA ranged from 4 to 203 micrograms/m3. The most heavily exposed workers had the highest mean postshift urine phthalate concentration (geometric mean 7.6 nmol/ml) (p = 0.015), and also the greatest mean increase (4.4 nmol/ml) in preshift to postshift urine phthalate levels. Twofold increases over the shift in urine phthalate concentration and postshift phthalate levels of greater than 10 nmol/ml were observed in 8 (25%) of 32 chemical operators, but in none of 52 other workers. These data suggest that measurement of urine phthalate levels may have utility for monitoring the exposure of workers manufacturing or using PA.