Symptoms of heat illness in surface mine workers

• Published in: International archives of occupational and environmental health Vol. 86; no. 5; pp. 519 - 527
• Main Authors: Hunt, A. P., Parker, A. W., Stewart, I. B.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-07-2013; Springer; Springer Nature B.V
• Subjects: Adult; Biological and medical sciences; Cross-Sectional Studies; Dehydration; Dehydration - complications; Earth and Environmental Science; Environment; Environmental Health; Female; Heat; Heat Stress Disorders - complications; Heat Stress Disorders - diagnosis; Heat Stress Disorders - epidemiology; Heat tolerance; Humans; Hydration; Male; Medical sciences; Mining; Mining industry; Occupational Diseases - complications; Occupational Diseases - diagnosis; Occupational Diseases - epidemiology; Occupational hazards; Occupational health; Occupational medicine; Occupational Medicine/Industrial Medicine; Original Article; Public health. Hygiene-occupational medicine; Queensland - epidemiology; Rehabilitation; Risk Factors; Self Report; Severity of Illness Index; Western Australia - epidemiology; Australia; Oceania; Western Australia; Queensland; Mine workers; Heat exhaustion; Heat illness; Dehydration; Hydration status; Human; Temperature; Environmental factor; Occupational exposure; Symptomatology; Heat; Exhaustion; Open pit mine; Heat stroke; Worker; Occupational medicine
• ISSN: 0340-0131; 1432-1246
• DOI: 10.1007/s00420-012-0786-0

Objective
To assess the symptoms of heat illness experienced by surface mine workers.
Methods
Ninety-one surface mine workers across three mine sites in northern Australia completed a heat stress questionnaire evaluating their symptoms for heat illness. A cohort of 56 underground mine workers also participated for comparative purposes. Participants were allocated into asymptomatic, minor or moderate heat illness categories depending on the number of symptoms they reported. Participants also reported the frequency of symptom experience, as well as their hydration status (average urine colour).
Results
Heat illness symptoms were experienced by 87 and 79 % of surface and underground mine workers, respectively (
p
 = 0.189), with 81–82 % of the symptoms reported being experienced by miners on more than one occasion. The majority (56 %) of surface workers were classified as experiencing minor heat illness symptoms, with a further 31 % classed as moderate; 13 % were asymptomatic. A similar distribution of heat illness classification was observed among underground miners (
p
 = 0.420). Only 29 % of surface miners were considered well hydrated, with 61 % minimally dehydrated and 10 % significantly dehydrated, proportions that were similar among underground miners (
p
 = 0.186). Heat illness category was significantly related to hydration status (
p
 = 0.039) among surface mine workers, but only a trend was observed when data from surface and underground miners was pooled (
p
 = 0.073). Compared to asymptomatic surface mine workers, the relative risk of experiencing minor and moderate symptoms of heat illness was 1.5 and 1.6, respectively, when minimally dehydrated.
Conclusions
These findings show that surface mine workers routinely experience symptoms of heat illness and highlight that control measures are required to prevent symptoms progressing to medical cases of heat exhaustion or heat stroke.