Biological monitoring of controlled toluene exposure

Abstract

After breathing rate and extrahepatic metabolism had been set to conservative (protective) values (the 97.5th and 2.5th percentiles, respectively) the model predicted that pre-final-shift breath levels of < or =10 micromol/m3 and post-final-shift levels of < or =150 micromol/m3 corresponded to average workplace exposure levels of < or =50 ppm toluene. Alternately, we used the distributions and covariances of the measured and fit model parameters to yield conservative pre-final-shift levels of < or =7.3 micromol/m3 and post-final-shift breath levels of < or =120 micromol/m3 that were reflective of workplace exposure levels of < or =50 ppm toluene.

A Field Method for Sampling Toluene in End-Exhaled Air, as a Biomarker of Occupational Exposure: Correlation with Other Exposure Indices.

“…These values are partially in agreement with a value of 4888 ng/L when the breath sample is collected the next morning, after an exposure of 376 mg/m 3 toluene, as reported by Campbell 1) and with a breath level of 972 ng/L pre-final shift exposure, reflective of exposure levels of 188 mg/m 3 , as reported by Pierce et al 2) . Differences in sample collection techniques and analysis can explain partially the lack of reproducibility of the results among the different authors.…”

“…Occupational overexposure is associated with mucous membrane irritation and decrement in central nervous system function 2) . The American Conference of Governmental Industrial Hygienists (ACGIH) 3) states an 8 h time-weighted average (TWA) threshold limit value (TLV) of 188 mg/m 3 for the concentration of toluene in the air of working environment, and adds the "skin" notation, to outline that toluene can be both inhaled and absorbed by the skin.…”

Determinação simultânea dos ácidos hipúrico e metil hipúrico urinários por cromatografia gasosa visando a biomonitorização de trabalhadores expostos por tolueno e ao xileno

“…Para realizar a biomonitorização de trabalhadores expostos tem sido propostos indicadores biológicos que se correlacionem com as concentrações de tolueno no ambiente ocupacional, ou seja, com a concentração de exposição/absorção: ácido hipúrico na urina, ácido benzóico na urina, orto-cresol na urina, ácido hipúrico no soro, tolueno no sangue, tolueno no ar exalado, tolueno na urina 3,4,9,17,30,33,40,52,57,65,76,79.…”

Occupational Exposure to Aromatic Hydrocarbons at a Coke Plant: Part II. Exposure Assessment of Volatile Organic Compounds

“…average intensity of exposure to toluene has been investigated by several authors [18][19][20][21] . In our work no statistically significant association was found between urinary 2-methylphenol and toluene in.…”

“…According to Inoue 22) , the urinary 2-methylphenol level is significantly reduced by smoking, drinking, and the two habits combined, therefore it cannot be considered reliable as a biological indicator of low-level exposure to toluene. The presence of 2-methylphenol in the urine of workers might be due to the exposure to toluene 21,23,24) as well as to 2-methylphenol. Phenolic compounds comprise approximately 5% of naphthalene oil and 33% of carbolic oil 25) .…”