Biological monitoring for occupational exposures to o-toluidine and aniline

Abstract

Epidemiological evidence that occupational exposure to o-toluidine and aniline is associated with an increased risk of bladder cancer led to efforts to identify biomarkers of workplace exposures to these aromatic amines. For the determination of o-toluidine and aniline in worker urine specimens, a method using high performance liquid chromatography (HPLC) followed by electrochemical detection was developed. The limits of detection were 0.6 microgram/l and 1.4 micrograms/l for o-toluidine and aniline, respectively. Recovery of o-toluidine and aniline from spiked urine averaged 86% and 93%, respectively, over a range of 4-100 micrograms/l. Reproducibility in the range 2-100 micrograms/l for analyses of split field samples was 13% (average RSD) for o-toluidine and 16% (average RSD) for aniline. Application of this method to pre- and post-shift samples collected from potentially exposed and unexposed workers indicated elevated concentrations of o-toluidine and aniline in urine from exposed workers. To develop methods for biomarkers of internal dose, o-toluidine binding to the blood proteins hemoglobin and albumin was investigated utilizing in-vivo (rodent) and in-vitro (hemoglobin and albumin) studies. Base-hydrolyzable protein adducts were analyzed by HPLC (fluorescence) and/or GC/electron capture (EC). The methods were compared for sample preparation requirements, selectivity and sensitivity. While the GC/EC method was more sensitive than HPLC, the presence of interfering peaks limited the utility of this approach. Results from these studies suggested that the HPLC method could be useful for determination of o-toluidine exposures in individuals acutely or chronically exposed to high levels.

Biomonitoring of urinary aromatic amines and arylamine hemoglobin adducts in exposed workers and nonexposed control persons

“…uidine, benzidine, dichlorobenzidine, monoacetylbenzidine, o-toluidine, diacetyl-o-toluidine, acetaniline) have been reported by different authors (Akiyama 1970 ;Ehrlicher 1958 ;Brown et al 1977, cited in Beratergremium ffir Umweltrelevante Altstoffe 1989 b; Dieteren 1966 ;Folland et al 1978 ;Genin 1977 ;Geyer and Fattal 1987 ;Hoechst 1986, cited in Beratergremium ffir Umweltrelevante Altstoffe 1989 a; Jurincic et al 1991 ;Lewalter 1985 ;Lowry et al 1980 ;Meal et al 1981 ;Teass et al 1993) We could determine a wide range of aromatic amines in occupationally exposed workers with the chromatographic method used in our study We detected different arylamines in the urine of occupationally not exposed smokers and nonsmokers (aniline, p-toluidine, 2-naphthylamine, 4-chloro-o-toluidine) Additionally, in smoking controls 4-chloroaniline, o-toluidine, m-toluidine, benzidine, and…”

Stoffmonographie und ­Referenzwerte für ­monocyklische Amino­aromaten im Urin. Stellungnahme der Kommission Human-­Biomonitoring des Umweltbundesamtes

“…Andere, bisher verwendete analyti sche Methoden waren deutlich we niger empfindlich und spezifisch. Dies betrifft vor allem Methoden, bei denen Hochdruckflüssigkeitschromatographie [5,58,59,60,61] oder die Gaschromato graphie in Verbindung mit verschiedenen Detektoren [62,63] zum Einsatz kommt. Zur Bestimmung der inneren Belastung durch einkernige Aminoaromaten, die sich vom Benzol und vom Toluol ableiten, haben Weiss und Angerer [64] eine GC/ MSMethode erfolgreich eingesetzt.…”

Urinary bisphenol a concentrations and ovarian response among women undergoing IVF

“…In addition, organic compounds such as phenols are glucuronidated in the liver and are eliminated by active tubular secretion, so that creatinine adjustment may not be appropriate (Teass et al, 1993). Urinary BPA concentrations were normalized for dilution using the formula Pc = P × [(1.024-1)/ (SG-1)], where Pc is the SG-corrected BPA concentration (μg/L), P is the observed BPA concentration (μg/L) and SG is the specific gravity of the urine sample (Boeniger et al, 1993;Teass et al, 1993). SG was measured using a handheld refractometer (National Instrument Company Inc., Baltimore, MD, USA), which was calibrated with deionized water before each measurement.…”