How do we assess mould levels? Testing the parameters of rapid adenosine bioluminescent swabs in conservation

Abstract

Successfully detecting and treating mould on cultural heritage to a ‘safe’ level is an important concern due to the variety of remediation approaches, substrates and health hazards posed by such fungi. In conservation, rapid adenosine bioluminescent swab testing has been used in two main applications: to identify if fungi are present, and to attempt to quantify if a remediated object is ‘clean enough’ for regular use or storage. A literature review across the food hygiene, healthcare and conservation sectors was combined with a simple lab experiment comparing RLU (Relative Light Unit) values obtained using a Kikkoman PD-30 lumitester with LuciPac Pen swabs on various surfaces against low magnification, high magnification and SEM imaging of the same samples. Results show it is impossible to establish numerical benchmarks for ‘clean enough’ and furthermore confirm that the devices are not ideal for diagnosing what is and is not mould. However, tracking the efficacy of remediation processes with the devices was successful when three sample areas were compared: a visually clean area before treatment, a visually mould damaged/dirty area before treatment, and the latter after a mould remediation treatment. This suggests that rapid adenosine bioluminescent swab testing can provide supporting evidence to conservators to make more informed decisions about how effective cleaning processes are for a particular artefact substrate.