Available online at www.ijmrhs.com I n t e r n a t i o n a l J o u r n a l o f M e d i c a l R e s e a r c h & H e a l t h S c i e n c e s • I J M R H S • International Journal of Medical Research & Health Sciences, 2020, 9(12): 52-58 52 ISSN No: 2319-5886 Effect of Benzoin Resin Fumes on Indoor Environmental Microbes Mashael W. Alruways, Intisar E. Elrayah*, Mariam A. Mansi Department of Clinical Laboratories, College of Applied Medical Science, Dawadmi, Shagra University, Saudi Arabia *Corresponding e-mail: elreyagh@su.edu.sa ABSTRACT Objective: This work aimed to investigate the antimicrobial effect of traditional Saudi Arabian incense (white benzoin resin, Jawi) on indoor environment microbes in Shaqra University, Dawadmi Female Student Campus, and bacterial isolates from patients in Dawadmi General Hospital. Methods: The effect of white benzoin resin fumes was tested directly on clinical bacterial isolates. The bacterial culture plates were incubated with benzoin resin fumes within a confined space. The microbial quality of indoor air in four laboratories, lecture rooms, library, and restroom of the students was measured, and the effect of benzoin resin fumes on these indoor microbes was determined. The settle plate method with open Petri dishes containing different culture media was used to collect samples two times daily before and after benzoin resin fumes were used. Results: The growth of Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans was completely inhibited after exposure to benzoin resin fumes for 90 min. The growth of Klebsiella pneumoniae, Escherichia coli, and Enterobacter aerogenes was inhibited by 79%, 68%, and 55%, respectively, after the same incubation time. Fumigation of selected university premises with the incense decreased the total bacterial count from 23.5 Colony-Forming Units (CFU) to 6.25 CFU. Conclusions: The application of benzoin resin fumes in some university premises showed a promising effect on decreasing the total number of microorganisms in the air of some rooms and inhibiting the growth of some pathogenic bacteria. Keywords: Benzoin resin fume, Bacterial isolate, Indoor environment microbe, University premise INTRODUCTION Indoor environments are the most important environmental factors that can influence health. The air quality of indoor environments is one of the main factors that affect the health, safety, and productivity of people. The presence of microorganisms, including bacteria, molds, and viruses, is one of the major problems that affect the quality of indoor air [1,2]. People spend 90 % of their time indoors breathing an average of 14 m 3 of air per day [3,4]. As such, people are highly exposed to indoor microorganisms. A review published by the World Health Organization on some epide- miological studies showed adequate evidence for the association between indoor dampness-related factors and a wide range of effects on respiratory diseases, including asthma development, asthma exacerbation, current asthma, respira- tory infections, upper respiratory tract symptoms, cough, wheeze, and dyspnoea [1]. Ceremonies were performed in the past to purify the environment by burning wood and odoriferous medicinal herbs [5]. Since the earliest times, the burning of frankincense and myrrh in places of worship for religious purposes had hygienic functions, can refine smell, and minimize pollution by purifying indoor air [5]. The fumigation of an operat- ing theatre with fumes of mustard, butter, and salt may be an early kind of “antisepsis” of the air, although it had been additionally performed to eliminate evil spirits [6]. Nowadays, different traditional practices involve the use of fumigation smokes within confined spaces to purify or disinfect the air and to clean the environment. The traditional use of fumes of resins in Arabic countries has many purposes: resin fumes are used for spiritual purpos- es, to provide a pleasant smell in homes and eliminate bad smells, improve the mood and eliminate negative energy, feelings of fatigue, lethargy and laziness and respiratory problems, such as colds and flu [7]. Recent studies have proven the efficacy of holy stick fumigation against infectious bacteria, as well as the efficacy