scholarly journals Review Article: Indoor Biological Contaminants in the Built Environment

2021 ◽  
Vol 16 (1) ◽  
pp. 34-45
Author(s):  
Nur Baitul Izati Rasli ◽  
Nor Azam Ramli ◽  
Mohd Rodzi Ismail

Occupants of buildings spent most of their time indoors and posed themselves to the indoor biological contaminants (i.e. bacteria and fungi) in the built environment. However, the factors that influenced the prevalence of suspended bacteria and fungi in the air of the built environment are not well recognised. Authorities must take the growth of biological contaminants seriously to prevent serious health effects among occupants of buildings. This review summarises the factors (i.e. outdoor air, dust, ventilation problems, humidity/moisture surface problems and human occupancy) of indoor biological contaminants and their species in buildings that could worsen the indoor air quality. Bacteria species could exist in various indoor buildings (i.e. schools, cafeterias, mosques, faculties, child day-care centres, hospitals, dwellings, educational buildings, homes, elderly care centres, libraries, restaurants, and factories). The dominant bacteria were Bacillus spp. (24.1 %), Staphylococcus spp. (20.7 %), and Micrococcus spp. (20.7 %) whereas for fungi species were Penicillium spp. (25 %), Cladosporium spp. (21.9 %), and Aspergillus spp. (21.9 %).

2011 ◽  
Vol 20 (6) ◽  
pp. 607-617 ◽  
Author(s):  
Nor Husna Mat Hussin ◽  
Lye Munn Sann ◽  
Mariana Nor Shamsudin ◽  
Zailina Hashim

This study reports the types and concentrations of bacterial and fungal bioaerosols found in five randomly selected primary schools in Malaysia. Normal flora bacteria was the most frequently isolated bacteria including Staphylococcus spp., Pseudomonas spp. and Bacillus spp. Terribacillus spp. found in this study had never been reported before. The most frequently isolated fungal genera were Aspergillus, Penicillium, Fusarium, Rhizopus and Zygomycetes. The average concentration of bacteria in indoor and outdoor air were 1025 ± 612 CFU/m3 and 1473 ± 1261 CFU/m3, respectively, while the average concentration of fungal bioaerosol in indoor and outdoor air were 292 ± 83 CFU/m3 and 401 ± 235 CFU/m3, respectively. The percentages of bacterial and fungal samples that were within the American Conference of Industrial Hygenists (ACGIH) recommended levels were 44% and 33.8%, respectively. The ratio of indoor to outdoor fungi concentration was below 1.0, suggesting minimal indoor generative source for fungal bioaerosols. However, the ratio of indoor to outdoor bacteria concentration was approaching 1.0, suggesting the presence of potential internal generative source and inadequate ventilation. Building occupants might be one of the potential sources of bacteria in the indoor air as the bacteria concentrations without occupants were significantly lower than with occupants (p < 0.05).


Sigurnost ◽  
2016 ◽  
Vol 58 (4) ◽  
pp. 311-318
Author(s):  
Anita Rakić ◽  
Katja Ćurin ◽  
Ivana Gjeldum

SUMMARY: Microorganisms in the air are part of the bioaerosol which is composed of different particles of biological substances, dust particles, bacteria cells and their portions, mould spores and a number of by-products of their metabolism. This research focuses on analysing the primary microclimate indicators (temperature and relative humidity) and the presence of microorganisms in the work environment (air). Measurements were taken after the process of sterilisation of infective waste over three months with the objective to determine the total number of aerobic mesophilic bacteria and the total number of moulds. The microclimate indicators were measured with an attested device. The study monitored the microbiological purity of the air in a given place using the sedimentation method, with samples subsequently processed in a microbiology lab in keeping with the prescribed standards. After incubation and following the counting of developed colonies on microbiological substrates (Tryptic soy agar and Sabouraud dextrose agar), different strains of bacteria and moulds were identified. The most common were Gram (+) sporogenes bacteria Micrococcus spp and Staphylococcus spp., and as for fungi the most commonly found were Aspergillus spp and Penicillium spp. It was found that temperature and relative humidity affect the total number of aerobic mesophilic bacteria and fungi which was confirmed using the Wilcoxon equivalent pairs test at the level of statistic significance p<0.05.


2017 ◽  
Vol 7 (1) ◽  
pp. 14-18
Author(s):  
Nayan Chandra Das ◽  
Farzana Hossaini ◽  
Saurab Kishore Munshi

The present study was carried out to assess the degree of microbiological proliferation in tannery wastes and the surrounding environment of the tannery industries. In this regard, a total of 8 tannery waste (n=4) and environmental (n=4) samples were tested. All the samples contained a huge load of bacteria and fungi in an average of 108 cfu/g or ml. An extended numbers of pathogenic bacteria were recovered. Among the pathogenic bacteria, Staphylococcus spp. was predominant. Most of the samples exhibited the presence of Pseudomonas spp. Salmonella spp. and fecal coliform were found each in one sample. Bacillus spp., Escherichia coli, Klebsiella spp. and Vibrio spp. were found in few samples. The average load of the pathogens was 104 cfu/g or ml. All the pathogenic isolates were found to be multidrug resistant. Higher resistance was found against penicillin and streptomycin. Tannery waste after lather treatment sample showed antibacterial activity against all the pathogens tested. Overall, presence of pathogenic microorganisms with multidrug resistance traits may pose serious public health threats. Stamford Journal of Microbiology, Vol.7(1) 2017: 14-18


2020 ◽  
Vol 2 (3) ◽  
pp. 603-608
Author(s):  
Ikpebivie Y. Oku ◽  
Ayodele A. Oyedeji ◽  
Akuru O. I.

Street vended fruits cause food borne illnesses in developing countries. This study was carried out to determine the microbiological safety of some street vended fruits sold in Yenagoa metropolis of Bayelsa State, Nigeria. Freshly cut ready-to-eat vended pawpaw, watermelon and pineapple were analysed for possible contamination with bacteria and fungi using standard microbiological techniques. A total of (17) samples: (5) Pawpaw, (6) Watermelon and (6) Pineapple were obtained from three (3) different local markets in Yenagoa metropolis, namely; Tombia, Opolo and Swali markets. Bacterial count ranged from 1.3x105 to 2.4x106cfu/ml for pineapple; 1.9x105 to 8.1x106cfu/ml for watermelon and 3.7x106 to 7.6x106cfu/ml for pawpaw samples. The highest bacterial count was obtained in watermelon from Opolo market, while the highest fungal count was recorded in pawpaw retailed at Opolo market. Microbial isolates were Bacillus sp, Escherichia coli, Salmonella sp, Staphylococcus sp, Klebsiella spp, Citrobacter spp, Proteus spp, Enterobacter spp, Mucor spp and Saccharomyces cerevisiae. There were 58.8% occurrence of Escherichia coli and Staphylococcus spp and occurred most. Bacillus spp and Klebsiella spp had 47.1% occurrence and closely followed by Staphylococcus aureus 41.2%, while Proteus spp had the least 5.9% occurrence. The result obtained may be responsible for the prevalence of Escherichia coli and Staphylococcus spp in Yenagoa metropolis. The presence of these organisms in these ready-to-eat retailed fruits analysed is a reflection of unwholesomeness and gross contamination of the fruits and therefore make the fruits unsafe for human consumption; hence the need for proper microbiological safety analysis of fruits for human consumption.


2002 ◽  
Vol 56 (1-2) ◽  
pp. 41-52 ◽  
Author(s):  
Zoran Masic ◽  
Dobrila Jakic-Dimic ◽  
Vidica Stanacev ◽  
Zlatan Sinovec

The paper presents the results of analyses of the chemical composition of 455 samples, microbiological analysis of 412 samples, and mucotoxicological analyses of 212 samples of feed mixes for different categories of swine which arrived for control at authorized laboratories from the territory of the Republic of Serbia during the period from 2000 until 2001. The analyses of 455 swine feed mix samples showed that as many as 185 feed mixes do not meet the quality condition on protein content envisaged by legal regulations, and the highest discrepancy was determined in feed mixes for piglets. Analyses of Ca, P and NaCl contents showed that the mixes in a large number of cases contain insufficient quantities, and in a considerable number even quantities which are not permitted. Analyses of the contents of certain microelements showed that mixes contain insufficient quantities in a large number of cases, especially of copper, manganese and zinc. The number of saprophytic bacteria greatly varied depending on the type of feed mix but all examined samples contained a permitted number of saprophytic bacteria. These analyses most often isolated Bacillus spp., Staphylococcus spp., coliform bacteries, and Micrococcus spp.. Most examined samples contained a permitted number of clostridia, and a smaller number of samples mostly for piglets, showed an impermissible number of clostridia. The quantity of mold fungi in mixes was significantly higher in mixes for young animals, and the determination of fungi most frequently resulted in the isolation of Penicillium spp., Aspergillus spp., Fusarium spp., and Mucor spp.. The mucotoxin analysis of 212 feed mixes showed that only 30.2% were within permitted levels, and the differences between the mixes for young and adult animals were not significant. The mucotoxins most often present were zearalenon and ochratoxin, and all mixes in which aflatoxin and trychotecenes were identified contained these toxins in quantities above permitted levels.


2021 ◽  
pp. 88-95
Author(s):  
V. O. Oramunwa ◽  
H. O. Agu ◽  
F. C. Ogbo

Vegetables are highly perishable commodities that easily get spoilt or deteriorate during handling along the supply chain from the producer to the final consumer. This study aims to compare the microbiological efficacy of hessian bags and non hessian bags on leafy vegetables (Telfairia occidentalis) Ugu and (Ocimum gratissimum) Nchuanwu leaves using hessian bags and non-hessian bagsduring distribution. Standard procedures on microbial count, isolationof microorganisms, purification of microbial isolates, biochemical identification of isolateswasused to identify the microorganisms present. The microbial load of the leafy vegetables from farmland to consumer increased progressively along the distribution chain. Staphylococcus species were the predominant bacteria in the leafy vegetables from the farmland. Other bacteria found were Pseudomonas, Bacillus spp, Staphylococcus spp, Escherichia coli and fungi Penicillium spp, Aspergillus niger, Rhodotorula spp, Fusarium spp, Mucor spp. The study showed that the microbial contents of the vegetables increased across the distribution line from farmland to consumer irrespective of the use of hessian bags.


CORD ◽  
2005 ◽  
Vol 21 (01) ◽  
pp. 34
Author(s):  
K.S.K.S. Fernando ◽  
N.A. Tennakoon ◽  
S. Widanapathirana

In Sri Lanka, coconut is cultivated under diverse soil conditions of varying fertility status available in different agro-climatic zones. Although chemical and physical characteristics in some of these soils are known, their biological properties are yet to be studied.  Hence the aim of this study was to determine the microbiological parameters in root zone of coconut grown in different soil series.  For this study, 20 different soil series in coconut growing area were analyzed for number of total bacterial and fungal colonies, identification of bacteria and fungi, biomass C and N; CO2 evolution and nitrogen mineralization.   The microbiological parameters varied with the soil series. The bacterial population densities were significantly (p=0.001) high in Ambakelle, Kalpitiya, Rathupasa and Madampe soil series while the fungal colonies were significantly (p=0.001) high in Thambarawa, Pallama, Wilatawa and Ambakelle soil series.   Only Kalpitiya, Kuliyapitiya, Gambura soil series contained biomass C more than 200 mg/100 g of soils.  Biomass N was the highest in Boralu soil series followed by Kalpitiya, Rathupasa and Gambura.  Carbon diozide evolution was high in Kalpitiya, Katunayaka, Wariyapola soil series while N mineralization rate was high in Ambakelle, Weliketiya and Rathupasa soil series.  Bacillus spp. were the dominant bacteria in all studied soil series.  In addition, Micrococcus, Staphylococcus, Enterobacter, Serratia, Corynebacterium, Pseudomonas and Actinomycetes were also identified. Fungi such as Penicillium, Aspergillus and Curvularia were common in most of the soil series than other species.


Author(s):  
H. O. Stanley ◽  
B. Onwuna ◽  
C. J. Ugboma

The aim of the study was to compare the indoor levels of airborne bacteria and fungi of air conditioned (AC) buildings and naturally ventilated (NV) buildings using a Supermarket, a Laboratory and an Eatery as a case study. The predominant bacterial isolates were Staphylococcus, Micrococcus spp., Escherichia coli, Bacillus spp., Streptococcus spp., Enterococcus spp., Klebsiella spp. The fungal isolates belong to the genera Penicillium, Aspergillus, Mucor, Trichophyton, Fusarium, Candida and Chaetomium. The levels of airborne bacteria and fungi were determined using settle plate method. In AC buildings the average air levels of bacteria (supermarket: 24.2 CFU m-3; laboratory: 29.2 CFU m-3; eatery: 51.0 CFU m-3 air) were higher than in NV (respectively: 54.3 CFU m-3; 100.7 CFU m-3; 134.3 CFU m-3 air). The average air levels for fungal isolates were higher in the eatery due to presence of poorly maintained AC system (supermarket: 7.8 CFU m-3; laboratory: 11.5 CFU m-3; eatery: 56.7 CFU m-3 air) than in NV (28.6 CFU m-3; 19.6 CFU m-3; 13.5 CFU m-3 air respectively). Findings from this study showed that AC buildings had lower levels of bacterial and fungal contamination compared to buildings with natural ventilation.


2019 ◽  
Vol 8 (1) ◽  
pp. 34-37 ◽  
Author(s):  
Saurab Kishore Munshi ◽  
Juel Roy ◽  
Rashed Noor

Cow dung is being used in agriculture as well for the household and religious purposes from the ancient time. Cow dung is known to possess antimicrobial activity and contains a wide variety of microorganisms with variable properties. Therefore, the present study was carried out to assess the microbial diversity including pathogenic ones of the cow dung samples as well as to determine the antimicrobial traits of the samples. In this regard, a total of 8 fresh cow dung samples were tested. All the samples contained a huge load of bacteria and fungi in an average of 108 and 107 cfu/g, respectively. An extended number of pathogenic bacteria were recovered. Among the pathogenic bacteria, Staphylococcus spp. and Bacillus spp. were predominantly found in every sample. The presence of Pseudomonas spp. Escherichia coli, Klebsiella spp. and fecal coliform were exhibited in most of the samples. Salmonella spp. and Vibrio spp. were found in 3 and 5 samples, respectively. The average load of the pathogens was 104 cfu/g. All the samples showed substantial degree of antimicrobial activity against all the pathogens tested. Samples 1, 2, 3 and 4 were effective in inhibiting the growth of all the tested pathogens. The findings of the present study revealed the need for safe application of cow dung in the agricultural field and of further investigation for the antimicrobial potential of the diversified microflora of cow dung offering agricultural, environmental and medical applications. Stamford Journal of Microbiology, Vol.8(1) 2018: 34-37


2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Davood Jalili ◽  
MohamadHadi Dehghani ◽  
Abdolmajid Fadaei ◽  
Mahmood Alimohammadi

This paper presents information about airborne microorganisms (bacteria and fungi) in the indoor air of two hospitals (Kashani and Hajar) in the city of Shahrekord, Iran. The settle plate technique using open Petri dishes containing different culture media was employed to collect a sample and using Quick Take 30 Sample Pump three days per week for a period of 8 weeks. Standard microbiological methods were employed for the identification of bacterial and fungal isolates. The results showed that the concentration of bacteria in the study area ranged from 0 to 70 cfu/plate/h, while the concentration of fungi was 0 to 280 cfu/plate/h. Also, 12 bacterial and 3 fungal species were isolated and identified with varying frequencies of occurrence, including Staphylococcus spp., Escherichia coli, Salmonella, Enterobacter, Pseudomonas, Serratia Citrobacter, Proteus, and Klebsiella, while the fungal genera isolated included Yeast, Aspergillus flavus, and Penicillium. While the bacterial isolates Staphylococcus aureus (20.50%) and Pseudomonas (9.10%) were the most predominant airborne bacteria, yeast (22.70%) and Penicillium (20.50%) were the most frequently isolated fungal species. The population of microorganisms was the highest during the afternoon. The statistical analysis showed a significant difference between the microbial loads of the two hospitals at P < 0.05 . The generated data underline the usefulness of monitoring the air quality of the indoor hospital.


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