A follow-up study on occupational exposure to inhaled anaesthetics in Eastern European surgeons and circulating nurses

Objective: Although no dose-response relationship exists for the health ris ks associated with the occupational exposure to inhaled anaesthetics, publi c health authorities recommend threshold values. The aim of the present stu dy was to assess whether and to what extent these threshold values are exce eded in surgeons and circulating nurses of an Eastern European university h ospital, before and after measures had been taken to reduce occupational ex posure. Methods: At nine workplaces, occupational exposure to nitrous oxide and the volatile anaesthetic used (halothane or isoflurane) was measured w ithin the breathing zones of surgeons and circulating nurses by means of ph otoacoustic infrared spectrometry. The measurements were carried out in 199 6 and were repeated in 1997 after the installation of active scavenging dev ices at five workplaces, and an air-conditioning system at one workplace. R esults: Occupational exposure to nitrous oxide and halothane or isoflurane was lower in 1997 compared with that of 1996. In 1996, 89% of the nitrous o xide values were above the European threshold value of 100 ppm, whereas in 1997 approximately 50% were above this limit. In 1996 the majority of the m easurements for the volatile anaesthetics were already below 5 ppm halothan e and 10 ppm isoflurane and the number of measurements exceeding these limi ts was further reduced in 1997. Conclusion: The measures taken were effecti ve in reducing waste gas exposure. Nevertheless, further efforts are necess ary, especially for nitrous oxide, to reach Western European standards and to minimise possible health risks. These efforts comprise the installation of (active) scavenging devices, air-conditioning systems and new anaesthesi a machines at all workplaces, the use of low-flow anaesthesia, the replacem ent of inhaled anaesthetics by intravenous anaesthetics and an appropriate working technique.