EPISODE OF TOXIC GAS EXPOSURE IN SEWER WORKERS

Objectives-Sewer workers are used to unpleasant smells, but may be req uired to investigate unusual ones. Twenty six men were involved in inv estigation of episodes of such a smell after neighbourhood complaints over several weeks. Methods-Workers exposed to the smell were investig ated by clinical follow up, lung function tests, and measurement of pi tuitary function. Results-14 of the 26 developed subacute symptoms inc luding sore throat, cough, chest tightness, breathlessness, thirst, sw eating, irritability, and loss of libido. Severity of symptoms seemed to be dose related. Minor symptoms resolved over several weeks but tho se more seriously affected have shown deteriorating respiratory sympto ms and lung function and remain unable to work a year after the incide nt. In one, evidence of mild cranial diabetes insipidus was found. Ana lysis of gas from the sewer showed the presence of a mixture of thiols and sulphides, known to be highly odorous and not normally found in s ewers. The source remains unknown. Conclusions-Several of these men se em to have developed delayed airways disease and disturbances of hypot halamic function. Such an outcome has not to our knowledge been descri bed before. Despite the presence of the smell, standard safety gas det ection equipment used to ensure the sewer was safe to enter failed to indicate the presence of a hazard. Protection against such incidents c an only be provided by the use of positive pressure breathing apparatu s.