Determination method for nitromethane in workplace air.
OBJECTIVE
The purpose of this research was to develop a determination method for nitromethane (NM) in workplace air for risk assessment.


METHODS
A suitable sampler and appropriate desorption condition were selected by a recovery test in which a spiked sampler was used. The characteristics of the proposed method, such as recovery, detection limit, and reproducibility, and the storage stability of the sample were examined.


RESULTS
A sampling tube containing bead-shaped activated carbon was chosen as the sampler. NM in the sampler was desorbed with acetone and analyzed by a gas chromatograph equipped with a flame ionization detector. The recoveries of NM from the spiked sampler were 81-97% and 80-98% for personal exposure monitoring and working environment measurement, respectively. On the first day of storage in a refrigerator, the recovery from the spiked samplers exceeded 90%; however, it decreased dramatically with increasing storage time. In particular, the decrease was more remarkable for the smaller spiked amounts. The overall LOQ was 2 microg/sample. The relative standard deviation, which represents the overall reproducibility, was 1.1-4.0%.


CONCLUSIONS
The proposed method enables 4-hour personal exposure monitoring of NM at concentrations equaling 0.001-2 times the threshold limit value-time-weighted average (TLV-TWA: 20 ppm) proposed by the American Conference of Governmental Industrial Hygienists, as well as 10-minute working environment measurement at concentrations equaling 0.02-2 times TLV-TWA. Thus, the proposed method will be useful for estimating worker exposure to NM.
Takeuchi
Akito
A
Osaka Occupational Health Service Center, Japan Industrial Safety and Health Association, 2-3-8 Tosabori, Nishi-ku, Osaka, Japan. a-takeuchi@jisha.or.jp
Nishimura
Yasuki
Y
Kaifuku
Yuichiro
Y
Imanaka
Tsutoshi
T
Natsumeda
Shuichiro
S
Ota
Hirokazu
H
Yamada
Shu
S
Kurotani
Ichiro
I
Sumino
Kimiaki
K
Kanno
Seiichiro
S
D016902:Air Pollution, Indoor / Q000032:analysis*; D002849:Chromatography, Gas; D008697:Methane / Q000031:analogs & derivatives* / Q000032:analysis; D009595:Nitroparaffins / Q000032:analysis*; D016273:Occupational Exposure / Q000032:analysis; D018570:Risk Assessment; D017132:Workplace / Q000592:standards
D009595:Nitroparaffins; D008697:Methane; C008640:nitromethane