Biological Monitoring of Styrene in FRP-Making Small Industries in Kumamoto,Japan－Winter-Summer Difference and Effect of Protective Masks in Practical Working Conditions

• Published in: Journal of Occupational Health 2002-03, Vol.44 (2), p.83-88
• Main Authors: Inaoka, Tsukasa, Nagano, Megumi, Kitano, Takao, Ushijima, Kayo, Minamoto, Keiko, Tasaki, Ryuji, Koyanagi, Atsuko
• Format: Article
• Language: English
• Subjects: Biological monitoring; FRP; Practical working conditions; Protective equipment; Seasonal difference; Styrene
• ISSN: 1341-9145; 1348-9585; 1348-9585
• DOI: 10.1539/joh.44.83

Objective: Studies were carried out in Kumamoto, Japan to examine 1) the winter-summer differences in the average individual exposure to styrene (8hr-TWA) and to end-shift-urinary mandelic acid (MA in g/g Cr), 2) the possible seasonal difference in their relationship, and 3) the protective etfect of a disposable particulate respirator containing charcoal fiber (called a "charcoal mask") and a charcoal granule cartridge-mask (called a "gas mask") In the real worklng conditions. Methods: Approximately 100 male and female workers from about 1O small industries were subjected to the studies first in winterand second in summer. Individual exposure to styrene was monitored with a passive sampler during work time, and end-shift-urine was collected to determine urinary MA excretion. The content of their activities and the types of protective equipment were observed and recorded by the minute throughout the working day. Results: Neither individual exposure to styrene nor urinary MA excretion differed at the time of the study in both "no-mask" and "gas mask" groups. The urinary MA excretion was related to individual exposure to styrene in both seasons, with the highest correlation coefficient in the "no-mask" group. Since the regression slope forthe "charcoal mask" group did not differ from that for "no-mask" grou p, the "charcoal mask" was judged to have little protective effect in practical working conditions. From the difterence in urinary MA values at 50 ppm (previous T. LV-TWA by ACGIH) of individual exposure to styrene In the two regresslons for "no mask" and "gas mask" groups, 49%/o of styrene was protected against by the "gas mask" in winter, and 45% in summer. Conclusions: Despite different physical environmental conditions, individual exposure to styrene and urinary MA excretion did not differ by season in FRP-making industries. A "gas mask" is more recommended than a "charcoal mask" when treating styrene, although their protective eftects are decreased in practical working settings. It is basically necessary to give correct information on and free access to such protective equipment to styrene-treating workers . (J Occup Health 2002 44: 83-88)