Exposure assessment of monoterpenes and styrene: a comparison of air sampling and biomonitoring

Abstract

Background: Within-and between-worker variance components have seldom been reported for both environmental and biological data collected from the same persons. Aims: To estimate these variance components and their ratio for air contaminants and urinary metabolites in two different work environments and to predict the attenuation of exposure-response relationships based on these measures. Methods: Parallel measurements of air and urine were performed among workers exposed to monoterpenes in sawmills (urinary metabolite: verbenol) and styrene in reinforced plastics factories (urinary metabolite: mandelic acid). Results: Among the sawmill workers, variance components of the air and urinary verbenol results were similar; for the reinforced plastics workers the estimated between-worker variance component was greater for styrene in air than mandelic acid in urine. This suggests that attenuation bias would be about equal if air or biological monitoring were employed for monoterpene exposures, but would be greater if urinary mandelic acid were used instead of airborne styrene in an investigation of styrene exposure. Conclusions: Personal air samplers provide data with similar or superior quality to urinary metabolites as measures of exposure to these monoterpenes in sawmills and styrene in reinforced plastics factories.

R-Limonene metabolism in humans and metabolite kinetics after oral administration

“…6 Extended scheme of the human in vivo LMN metabolism; not verified metabolites (grey, narrow); established metabolites (grey, bold); newly proven metabolites (black, bold); epoxide hydrolase (EH); oxidation (Ox); reduction (Red); enantiomers not shown is almost entirely cleared from the metabolites within 24 h post-oral exposure. Consequently, in accordance with previous approaches on human biomonitoring of monoterpenes (Eriksson and Levin 1996;Levin et al 1992;Liljelind et al 2003;Schmidt et al 2015b), we recommend the determination of LMN metabolites in urine as powerful parameters for biological LMN exposure assessment.…”

Evaluating measurement error in estimates of worker exposure assessed in parallel by personal and biological monitoring

“…Studies to assess measurement error in monitoring data have been carried out on workers exposed to styrene in the reinforced plastics industry [Rappaport et al, 1995;Symanski et al, 2001;Liljelind et al, 2003], mercury in the chloralkali industry [Symanski et al, 2000], and dust in the carbon black manufacturing industry [van Tongeren et al, 1997], the construction industry [Tjoe et al, 2004], and sawmills [Teschke et al, 2004]. Taken together, these studies indicate that attenuation effects of imperfectly measured exposure can be quite substantial.…”

“…Taken together, these studies indicate that attenuation effects of imperfectly measured exposure can be quite substantial. Few studies, however, have had the requisite data to make comparisons between different methods of assessing exposure [Rappaport et al, 1995;Symanski et al, 2000;Symanski et al, 2001;Liljelind et al, 2003;Lin et al, 2005], and none employed a study design to insure that the same workers were monitored over common periods using multiple sampling methods. Thus, we carried out a study to quantify measurement error in multiple measures of exposure collected in parallel on groups of workers exposed to different contaminants from a broad cross-section of industries.…”

Monocyclic and bicyclic monoterpenes in air of German daycare centers and human biomonitoring in visiting children, the LUPE 3 study

“…procedure of the recent study. Furthermore, the monitoring of verbenols in urine was applied in three occupational field studies (Eriksson et al, 1996(Eriksson et al, , 1997Liljelind et al 2003). All studies found terpene exposure in the workplace air in the range of 20-120 mg m − 3 and median verbenol levels (sum of cVER and tVER) in the urine of the workers in the range of 6-24 mg L − 1 , which fits well with the much lower indoor air exposure and the urinary MTp metabolite levels of the recent study.…”

“…Solely three pilot studies applied αPN biomonitoring on post-shift urine samples of workers in Swedish and Finish saw mills. The studies showed strong and significant correlations of αPN or total MTps in indoor air with urinary verbenols, indicating that MTp biomonitoring may be successfully used for internal MTp exposure assessment (Eriksson et al, 1996;Liljelind et al, 2003;Rosenberg et al, 2002). However, there are no studies correlating indoor MTp levels with biomonitoring data of the general population.…”