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[Display omitted] • A simple and efficient microextration for determination of 1-naphtol and 2-naphtol. • Simple separation of extracted phase using magnetic stir bar in a rapid procedure. • Showing the efficiency of magnetic ionic liquid for biological monitoring of naphtalene. • Good applicability in real urine samples with good accuracy and precision. Naphthalene is one of the few volatile bicyclic aromatic hydrocarbons and a white crystalline solid that can sublimate at room temperature. Since 2000, according to the results of animal studies on the carcinogenic effects of naphthalene, this substance has been recognized as a major problem for the environment and industrial environments. Exposure to naphthalene leads to kidney toxicity, hemolytic anemia and other health problems in the human body. The International Agency for Cancer has placed naphthalene in group 2B (probably carcinogenic to humans). 1- naphthol and 2- naphthol are biological urinary indicators of human exposure to naphthalene in work environments. For the first time in this research, the concentration of 1-naphthol and 2-naphthol in urine, which serves as an indicator of naphthalene exposure, was performed through a method known as magnetic ionic liquids-based disperse liquid – liquid microextraction (MIL-DLLME). Subsequently, the samples were analyzed using gas chromatography with a flame ionization detector (GC-FID). Additionally, the factors that influence the extraction of this metabolite, such as the quantity of extracting solvent, speed of mixing, proportion of salt added, duration of mixing, and pH value, were determined using both a two-level factorial test design and a central composite design. Calibration curves were developed under optimal conditions, and the validity of the developed microextraction method was studied with different statistical methods and the analysis of real samples. A strong linear correlation between the subpeak level and the corresponding concentrations was observed in the range of 0.5–0.002 μg/ml for 1-naphthol and 2.00–0.001 µg mL-1for 2-naphthol. In addition, the detection limit and quantitative detection limit for 1-naphthol were 0.0006 µg mL−1, 0.002 µg mL−1, and 0.0003 µg mL−1, 0.001 µg mL-1for 2-naphthol respectively. The MIL-DLLME extraction method can be regarded as an environmentally friendly microextraction technique since it eliminates the need for dispersing solvents and toxic organic solvents as extractants. Results showed that the proposed technique can be applied for biological monitoring of the biomarkers of naphthalene in the exposed workers during occupational or environmental assessments. [ABSTRACT FROM AUTHOR]

The effect of ambient air pollution on panic disorder in the general population has not yet been thoroughly elucidated, although the occurrence of panic disorder in workers exposed to organic solvents has been reported previously. We investigated the association of ambient air pollution with the risk of panic attack-related emergency department visits. Using health insurance claims, we collected data from emergency department visits for panic attacks in Seoul, Republic of Korea (2005-2009). Daily air pollutant concentrations were obtained using automatic monitoring system data. We conducted a time-series study using a generalized additive model with Poisson distribution, which included spline variables (date of visit, daily mean temperature, and relative humidity) and parametric variables (daily mean air pollutant concentration, national holiday, and day of the week). In addition to single lag models (lag1 to lag3), cumulative lag models (lag0-1 to lag0-3) were constructed using moving-average concentrations on the days leading up to the visit. The risk was expressed as relative risk (RR) per one standard deviation of each air pollutant and its 95% confidence interval (95% CI). A total of 2320 emergency department visits for panic attacks were observed during the study period. The adjusted RR of panic attack-related emergency department visits was 1.051 (95% CI, 1.014-1.090) for same-day exposure to ozone. In cumulative models, adjusted RRs were 1.068 (1.029-1.107) in lag0-2 and 1.074 (1.035-1.114) in lag0-3. The ambient ozone concentration was significantly associated with emergency department visits for panic attacks. [ABSTRACT FROM AUTHOR]

N -alkyl-2-pyrrolidones are important organic solvents for varnishes in industry. This study investigates exposure to N -ethyl-2-pyrrolidone (NEP) in varnishing of hard plastic components in an automobile plant. Two specific biomarkers of exposure, 5-hydroxy- N -ethyl-2-pyrrolidone (5-HNEP) and 2-hydroxy- N -ethylsuccinimide (2-HESI), were analyzed in urine samples of 14 workers. For this purpose, pre-shift, post-shift and next day pre-shift urine samples were collected midweek. Twelve workers performed regular work tasks (loading, wiping and packing), whereas two workers performed special work tasks including cleaning the sprayer system with organic solvents containing N -alkyl-2-pyrrolidones. Spot urine samples of nine non-exposed persons of the same plant served as controls. Median post-shift urinary levels of workers with regular work tasks (5-HNEP: 0.15 mg/L; 2-HESI: 0.19 mg/L) were ∼5-fold higher compared to the controls (0.03 mg/L each). Continuously increasing metabolite levels, from pre-shift via post-shift to pre-shift samples of the following day, were observed in particular for the two workers with the special working tasks. Maximum levels were 31.01 mg/L (5-HNEP) and 8.45 mg/L (2-HESI). No clear trend was evident for workers with regular working tasks. In summary, we were able to show that workers can be exposed to NEP during varnishing tasks in the automobile industry. [ABSTRACT FROM AUTHOR]

Abstract: Aging adults represent the fastest growing population segment in many countries. Physiological and metabolic changes in the aging process may alter how aging adults biologically respond to pollutants. In a controlled human toxicokinetic study (exposure chamber; 12m3), aging volunteers (n =10; >58 years) were exposed to propylene glycol monomethyl ether (PGME, CAS no. 107-98-2) at 50ppm for 6h. The dose-dependent renal excretion of oxidative metabolites, conjugated and free PGME could potentially be altered by age. Aims: (1) Compare PGME toxicokinetic profiles between aging and young volunteers (20–25 years) and gender; (2) test the predictive power of a compartmental toxicokinetic (TK) model developed for aging persons against urinary PGME concentrations found in this study. Methods: Urine samples were collected before, during, and after the exposure. Urinary PGME was quantified by capillary GC/FID. Results: Differences in urinary PGME profiles were not noted between genders but between age groups. Metabolic parameters had to be changed to fit the age adjusted TK model to the experimental results, implying a slower enzymatic pathway in the aging volunteers. For an appropriate exposure assessment, urinary total PGME should be quantified. Conclusion: Age is a factor that should be considered when biological limit values are developed. [Copyright &y& Elsevier]

Abstract: A rational medical, occupational and toxicological approach is instrumental to select objectively among pregnant women exposed to chemicals at the workplace those who should be withdrawn or benefit from improvements of working conditions. Risk assessment is based on a comprehensive review of compounds’ hazards and a thorough evaluation of the actual exposure including biomonitoring whenever as possible. Since 1996, the Lyon Poison Center has been conducting a prospective follow-up of pregnant women exposed to chemicals at the workplace. Of these, 206 exposed to organic solvents since conception were selected and matched with 206 exposed to a non-embryotoxic agent. Total withdrawal from the workplace was recommended in 22% of cases, but exposure was not considered to be hazardous to pregnancy in 51%. Overall, no increase in adverse outcomes was found. Maintaining pregnant women at their workplace, particularly most of the laboratory technicians, is reasonably possible after careful toxicological risk assessment. [Copyright &y& Elsevier]

The FIOH quality assurance programme for organic solvents and their metabolites consists of analyses for 2,5-hexadione, phenol, mandelic acid, methylenedianiline, methylhippuric acid, trans,trans-muconic acid and trichloroacetic acid in urine, and creatinine and relative density for standardisation. Four times a year two levels of spiked urine or urine specimens collected from occupationally exposed workers are distributed to the participants in 22 countries. RSD and recovery were studied during 1997–2000. Average RSDs of all participants varied between 23 and 56% and were clearly dependent on the analytical method used and the concentration level of the samples. Since 1997 the target values have been determined in reference laboratories for five of the analytes. Lower RSDs (9–21%) and good recoveries were obtained for all analytes in these laboratories, indicating that good performance can be achieved even in the complex analyses performed in biological monitoring of exposure to industrial chemicals. [ABSTRACT FROM AUTHOR]

• Determination of occupational exposure of VOC in the University community. • Development and validation of bioanalytical method for simultaneous exposure solvents. • Biological evaluation as tool for assessing occupational exposure. Occupational exposure to volatile organic compounds (VOC) might generate serious worker health damages. Therefore, biological monitoring is essential to evaluate exposure biomarkers from highly toxic chemicals, ensuring better attention to the worker health. In this study was developed and validated a bioanalytical method based on high-performance liquid chromatography coupled to photodiode array (HPLC-PDA) for the quantification of VOC biomarkers in urine samples from Federal University of Goias (UFG) workers. Samples were collected from 30 occupationally exposed subjects after application of a questionnaire survey. The following biomarkers hippuric acid, methyl-hippuric acid, mandelic acid, phenylglyoxylic acid and phenol were quantified, representing exposition to toluene, xylene, styrene, ethylbenzene, benzene and phenol solvents, respectively. Hippuric acid levels were found close to or above the reference values, although a subject had levels higher than preconized by Biological Limit Values (BLV) guideline of 4.0 mg/g creatinine. Five subjects had 3 and 4-methylhippuric acid ranging from 0.1 to 1.0 mg/g creatinine. These results indicate a moderate to high VOC exposure from UFG workers. Multivariate analysis generated four clusters and indicated that histotechnicians and graphic workers need especial attention on occupational VOC exposure. The results from this study reinforce the need for reliable methods able to the biological monitoring as an important tool for assessing occupational exposure. [ABSTRACT FROM AUTHOR]