| Popis: |
Received 8 September 2005; in final form 15 December 2005; published online 18 May 2006Some substances are familiar only to those who workin certain industries. Bitumen is something that wehave all seen applied in road repair, and we may beaware of less obvious uses. Studies on it are fre-quently reported in this journal, often with emphasison polyaromatic hydrocarbon exposure (e.g. Burstynetal.,2002;McCleanetal.,2004a,b;Va¨a¨na¨nenetal.,2005). In June 2006, bitumen is the subject of aconference in Dresden organized by ACGIH and aCommission of the Deutsche Forschungsgemeinsch-aft (DFG) (http://www.acgih.org/events/course/asphalt.htm). In Germany, the substance has becomean example of cooperative venture between industryand regulators, and in this commentary we attempt tosummarize what has taken place. One consequenceis a wide-ranging study of exposure, a total of1272 samples of vapours and aerosols of hot bitumengatheredbetween1991and2005,whichisreportedinthis issue (Ru¨hl et al., 2006).We will follow the European convention of using‘asphalt’ to refer to a mixture of organic binder(‘bitumen’) and filler such as sand or gravel.In Germany the legally binding standards are thelimit values and classifications published in theTRGS (Technical rules for hazardous substances).For a long time, bitumen was classified in theTRGS as a suspected carcinogen, which meant thatit was also automatically included in the DFG’sannual ‘List of occupational exposure limit (MAK)and biological monitoring guidance (BAT) values’,where it was listed as a suspected carcinogen from1977 onwards. However, it did not appear in theEuropean Union carcinogen lists. In the mid-1990sthis national carcinogenicity classification wasexamined, and also the exposure limits in air forvapours and aerosols released from work with hotbitumen.The new German threshold limits for vapours andaerosols of bitumen were assigned in autumn 1996.The Hazardous Substances Committee (AGS)decided that the threshold limit of 15 mg m |
