Investigation into the environmental factors associated with the incidence of skin disease following an outbreak of Miliaria rubra at a coal mine.
A retrospective study was undertaken to examine by interactive linear modeling a possible association between environmental conditions and the incidence of skin conditions (excluding athletes foot) in a coal mine following an increase in skin rashes, mainly 'prickly heat' (Miliaria rubra). An increase in the incidence was found with increasing surface temperature and underground air velocity; a decreased incidence with increased underground air quantity (air volume per unit time); whilst the relationship with underground temperature was found to be quadratic with incidence decreasing until 27 degrees C wet bulb (although this is not necessarily the optimum temperature for other purposes) and then increasing. The association between skin incidence and environmental factors was strongest (in terms of variance explained) when the incidence was associated with the environmental conditions of 4 to 8 weeks previously. The constant nature of relative humidity over the period prevented an examination of its relationship with rash incidence. Possible strategies for reducing the incidence of 'prickly heat' are discussed.