Metal fume fever
Metal fume fever is a (typically) self-limiting disease due to exposure to fumes emanating from working metal, e.g. welding. Polymer fume fever is a related, yet distinct, condition.
Due to gradual improvements in health and safety over the past 100 or so years, a marked decline in recorded cases of metal fume fever has been seen. Nevertheless, up to 2500 cases are still diagnosed in the USA per annum, and in Victoria, Australia, 85 cases were identified in a retrospective study looking at the preceding 5.5 years:
- 99% cases in adults
- 96% cases in men
- rapid onset of symptoms (5-10 hours) following exposure to the fumes
- flu-like symptoms
- fever, rigors, arthralgia, myalgia, headache, malaise
- generally, the condition is self-limiting with no long term sequelae
- rarely severe symptoms may result
- if exposure to the fumes continues through the working week then rapid tolerance is usual, such that symptoms are much better by Friday. Therefore symptoms tend to maximize in severity on the first return to work after a weekend or any time away from the workplace.
- diagnosis is usually clinical
Exposing metal to very high temperatures, such as occurs in welding, and related processes, results in the emanation of "metal fumes", which are defined as solid submicron-sized particles formed by the condensation of aerosolized metal compounds 1.
Zinc oxide is the most commonly implicated metal compound. Although the fumes can contain a wide range of metals including zinc, copper, manganese, chromium, iron, titanium, cadmium and nickel. The relative proportions of the various metals are conditional upon the form of welding employed, the metals being worked, etc. Zinc aside, it is contentious if some or most of these metals actually contribute to the pathogenesis of metal fume fever.
The underlying pathogenesis is still being researched but is likely secondary to both immune and non-immune mediated mechanisms.
Chest imaging usually shows clear lung parenchyma and CT may show mild atelectasis or pleural effusions. Much less commonly, bilateral patchy ground-glass opacities, or even consolidations, may be seen, with an appearance mimicking acute respiratory distress syndrome (ARDS).
Treatment and prognosis
Treatment tends to be supportive and in the vast majority recovery is rapid. No deaths have been recorded.
History and etymology
First published case is from 1831 1. Metal fume fever has a very long list of historic synonyms, related to its historic association with zinc working, including brass founder’s ague, brass chills, zinc fever, zinc fume fever, zinc chills, copper fever, foundry fever, spelter’s shakes, smelter’s chills, galvanizer’s poisoning, and glavo and metal shakes.