Determination of five phthalate monoesters in human urine using gas chromatography-mass spectrometry.
We have developed a gas chromatography-mass spectrometry (GC-MS) method to determine five phthalate monoesters (monoethyl phthalate (MEP), mono-n-butyl phthalate (MBP), mono-(2-ethylhexyl) phthalate (MEHP), monoisononyl phthalate (MINP) and monobenzyl phthalate (MBz)) in human urine. Human urine samples were subjected to enzymatic deconjugation of the glucuronides followed by extraction with hexane. The extracted phthalate monoesters were methylated with diazomethane, purified on a Florisil column and then subjected to GC-MS analysis. The recoveries from urine spiked with five phthalate monoesters were 86.3%-119% with coefficients of variation of 0.6%-6.1%. We measured phthalate monoester levels in human urine by analyzing 36 samples from volunteers. MBP and MEP were detected in all samples, and their median concentrations were 60.0 and 10.7 ng/mL, respectively. MBzP and MEHP were found in 75% and 56% of samples, and their median concentrations were 10.9 and 5.75 ng/mL, respectively. MINPs were not detected in most samples (6% detectable). Women had significantly (p < 0.05) higher mean concentrations of MBP and MEP than men. The estimated daily exposure levels for the four parent phthalates excluding diisononyl phthalate ranged from 0.27 to 5.69 mug/kg/day (median).
Kondo
Fumio
F
Department of Toxicology, Aichi Prefectural Institute of Public Health, 7-6 Nagare, Tsuji-machi, Kita-ku, Nagoya 462-8576, Japan. fumio@ipc-tokai.or.jp
Ikai
Yoshitomo
Y
Hayashi
Rumiko
R
Okumura
Masanao
M
Takatori
Satoshi
S
Nakazawa
Hiroyuki
H
Izumi
Shun-ichiro
S
Makino
Tsunehisa
T
D000328:Adult; D004051:Diethylhexyl Phthalate / Q000031:analogs & derivatives / Q000652:urine; D004785:Environmental Pollutants / Q000652:urine*; D004952:Esters / Q000652:urine*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D020719:Glucuronides / Q000378:metabolism; D006586:Hexanes / Q000737:chemistry; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D010795:Phthalic Acids / Q000652:urine*; D010968:Plasticizers / Q000032:analysis / Q000378:metabolism; D012997:Solvents / Q000737:chemistry
D004785:Environmental Pollutants; D004952:Esters; D020719:Glucuronides; D006586:Hexanes; D010795:Phthalic Acids; D010968:Plasticizers; D012997:Solvents; C471400:monoisononylphthalate; D004051:Diethylhexyl Phthalate; C016599:mono-(2-ethylhexyl)phthalate; C027561:butylbenzyl phthalate; C028577:monobutyl phthalate