Abstracts: ISEE 22nd Annual Conference, Seoul, Korea, 28 August-1 September 2010: Exposure Assessment by Various Media and Pathways
1School of Human & Environmental Sciences, Eulji University, Seongnam, Republic of Korea; 2Department of Occupational & Environmental Health, Yonin University, Yongin, Republic of Korea; and 3School of Public Health, Seoul National University, Seoul, Republic of Korea.
Abstracts published in Epidemiology have been reviewed by the societies at whose meetings the abstracts have been accepted for presentation. These abstracts have not undergone review by the Editorial Board of Epidemiology.
It is very difficult to exactly estimate the dose of dialkylated phthalates taken up by the general population because of environmental contamination, especially in the case of di-(2-ethylhexyl) phthalate (DEHP). We performed this study to estimate daily intake of DEHP, diethyl phthalate (DEP), and dibutyl phthalate (DBP) by urinary metabolites.
We used LC/MS/MS with on-line enrichment and column-switching techniques for the biological monitoring. Metabolites determined were 4 primary metabolites: mono(2-ethylhexyl)phthalate (MEHP), mono(n-butyl)phthalate (MnBP), mono(iso-butyl)phthalate (MiBP), mono-ethylphthalate (MEP); and 2 secondary metabolites of DEHP: mono(2-ethyl-5-hydroxyhexyl)phthalate (5OH-MEHP) and mono(2-ethyl-5-oxo-hexyl)phthalate (5oxo-MEHP). The subjects of the study (n = 332) were divided into 60 children, 62 middle and high school student, 139 adults, and 61 elderly man in Korea. The subjects were not occupationally exposed to phthalates.
Determined median daily DEHP, DBP, and DEP intake was 8.3, 7.9, and 5.8 μg/kg body weight (bw)/d, respectively. For DEHP, 5 people (1.5%) exceeded the value of the tolerable daily intake of the European Food Safety authority of 50 μg/kg bw/d, whereas 7.2% exceeded the reference dose of 20 μg/kg bw/d of the US Environmental Protection Agency.
Determination of urinary metabolites of phthalates enabled to estimate internal exposure to phthalate diesters, such as DEHP, DBP, and DEP.