Evaluation of the interaction of benzene and toluene on the urinary excretion of t, t-muconic acid in rats

Evaluation of exposure biomarkers in offshore workers exposed to low benzene and toluene concentrations

“…We did not have any information on the use of sorbic acid in the food served to the workers. Also, although at a higher exposure level than in the present study, co-exposure to toluene in rats has been shown to lower t,t-MA exposure in a concentration-dependent manner (Brondeau et al 1992). Biomarker correlations were strong between urinary and blood benzene as has been shown in other studies (Hoet et al 2009).…”

“…We also found that the internal concentrations of benzene appeared higher than expected considering the measured individual benzene exposure in air (Kirkeleit et al 2006b). This could either be due to co-exposure to other aromatic hydrocarbons, which may inhibit benzene metabolism (Boogaard and van Sittert 1994;Brondeau et al 1992;Inoue et al 1988), greater than average uptake due to physical exertion, or that especially benzene, which carries an ACGIH skin notation, may also enter the body via dermal absorption (ACGIH 2001;Adami et al 2006;Carlsson 1982;Nomiyama and Nomiyama 1974). In order to reduce health risks in the upstream petroleum industry, there is a need for more knowledge about exposures to hydrocarbons simultaneously present in crude oil.…”

Effects of permissible maximum-contamination levels of VOC mixture in water on total DNA, antioxidant gene expression, and sequences of ribosomal DNA of Drosophila melanogaster

“…The vast majority of current research performed on humans (Wallace 1996;Adgate et al 2004), rats, and mice (Ungvary and Tatrai 1985;Keller and Snyder 1988) has focused on individuals that are exposed to a variety of concentrations, times, and frequencies. However, some earlier observations were made on mammalian cells (in vitro) with detected toluene (2.16 ppm), ethylbenzene (6.05 ppm), xylene (9.78 ppm), and benzene (73 ppb) mixture and rats (benzene and toluene at 20-100 ppm); zebra fish (Danio rerio) and medaka (Oryzias latipes) (mixtures of benzene and toluene at 20-100 ppm); and Drosophila (mixtures of benzene and toluene, toluene and xylene, benzene and xylene, and benzene, xylene, and toluene at 25-100 mM) after their co-exposure to VOC mixtures (Inoue et al 1988;Brondeau et al 1992;Mizell and Romig 1997;Singh et al 2010;Kim et al 2011). …”

High Background Levels of Urinary Benzene Metabolites Found in a Volunteer Study

“…For example, the concentration of toluene present during this study ranged from 0.16 ppm to 0.6 ppm collected in 1-hr personal samples, and low-level toluene exposures may increase the levels of urinary phenol and suppress the levels of ttMA found in the urine of benzene exposed workers. (1,19,20) Inoue et al (21) showed that in the presence of other aromatic compounds, sPMA may be a more reliable biological indicator of airborne benzene exposure than ttMA and/or phenol. However, the impact of the other contaminants measured in the simulation study could not be determined based on the results of this urine study.…”

“…The simulation study occurred during a 4-day period from July [18][19][20][21]2005, in a residential two-car garage in Boulder, Colorado. Eleven different product-use scenarios were evaluated that varied according to the following parameters: amount of benzene in each product, the type of product used, the quantity of product used, and the ventilation rate.…”