Asthma in the aluminium industry


Occupations
  • Foundry worker
  • Metallurgist
Agents
Aluminium, Aluminium salts, Fluorides.
 
Incidence
Incidence less than 4%.
 
Smoking is a common habit amongst these workers and aggravates the condition. The inflammatory factor caused by the irritant plays a role in the development of chronic symptoms. Bronchial hyperreactivity and airways obstruction syndrome may persist after exposure to the risk has ceased. Aluminium sulphates and fluorides used during the electrolytic extraction process are toxic. Elevated levels of blood eosinophils may be a risk factor.
 
Conditions
The sulphates and fluorides of aluminium used during the electrolytic extraction process are toxic. The limit for occupational exposure is 0.5 mg/m3.
 
Excessive inhalation of fluorides may give rise to RADS (Reactive airways dysfunction syndrome or asthma caused by irritants – Brook's syndrome).
 
Symptoms
Cough, dyspenoea, wheezing and difficulty in breathing are frequent symptoms. Initially, the symptoms are directly associated with exposure to the risk (ceasing at the weekend), but may eventually become permanent with time.
 
In the past, the causative agent was unclear: either it could have been an irritant action due to a hydrogenated fluoride or a specific reaction due to aluminium chloride. It has now become clear that the reaction is specific and due to aluminium chloride and this has been demonstrated by bronchial provocation tests.
 
Diagnostic methods
No immunological assay or bronchial provocation test. An epidemiological approach must be adopted for diagnosis. Plasma fluoride concentrations of up to 10 ng/ml have been observed. The plasma concentration is directly related to the exposure.

References

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  2. Allergy 2000,55:779 Burge P.S. et al.
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  12. Eur. J. Resp. Dis. 1985,66:105

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.