passive sampling

Research on the relationship between bioaerosols and particulate matter (PM) concentrations is necessary, especially in hospitals where airborne bioaerosols can facilitate disease transmission. This study aimed to investigate the relationship between PM (PM2.5 and PM10) and bioaerosols, as well as the factors influencing them (temperature and humidity), in the air of liver transplant operating rooms (LTOR) at Imam Khomeini Hospital in Tehran.

Bioaerosol samples (32 samples) were collected using the passive sampling method, employing open-door plates containing culture medium, during June and July of 2019. PM samples were obtained concurrently with bioaerosol samples using the GM8803 air quality detector, during four one-hour periods. Simple linear regression analysis was performed to determine the relationship between bioaerosol and PM concentrations.

It was revealed that the average concentrations of PM2.5 and PM10 were 17.8 (SD = 2.2) and 27.0 (SD = 2.6) μg/m3, respectively. Additionally, the average concentrations of bacterial and fungal bioaerosols were 2132 (SD = 837) and 550 (SD = 189.4) CFU/m2.h, respectively. Linear regression analysis demonstrated a strong correlation between bacterial bioaerosols and PM concentrations, whereas the relationship with fungal bioaerosols was relatively weaker.

The findings of this study indicate that the indoor air in LTOR exhibits a higher level of microbial contamination than the recommended guidelines for high-risk environments. To improve the air quality in LTOR, it is recommended to implement periodic microbial monitoring, ensure the proper functioning of ventilation systems, and pay attention to their maintenance and operation.

In this work, we target the analysis and the characterization of bioaerosols species present in medical emergency of north Algerian hospital, were we consider in four operating rooms, two preoperative and resuscitation rooms.

Passive technique was applied for the collection of bacterial and fungal samples in indoor air, for three days from 16 to 18 January 2018. Two techniques were then chosen for the bacterial identification, the Analytical Profile Index (API) system and Matrix Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS).

It has been found that fungal contamination was highest in neurosurgery block, 103 CFU/m3
, whereas the highest bacterial contamination, 2645 CFU/m3 , was noted in postoperative room. The most predominant identified bacteria were Gram-positive cocci.

The high contamination in bioaerosols and the types of bacteria identified in the premises studied increase the risk of contracting a nosocomial infection, hence the importance of daily disinfection and sterilization of hospitals area in order to reduce bioaerosols dangerous effects on human health

 This study was conducted to determine Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) concentration regarding broken petroleum transmission pipeline in the east region of Isfahan, using passive sampling method. 

 Dialysis bags as passive sampling devices with molecular cut-off diameter of 12000 Dalton, 3.2 cm width and around 12 cm lengths were used that contain 2 ml of olive oil as an absorbent. These devices were placed, in 10 sampling wells for 45 days. In order to determine the absorption efficiency of these devices, laboratory calibration operations were performed at the same time. Nitrate as an indicator of contamination of groundwater with chemical fertilizers and also electrical conductivity (EC) as an indicator for cations and anions concentration was measured. 

 The laboratory absorption efficiencies of BTEX were found to be 90%, 85%, 79%, and 81%, respectively. Concentration of these compounds in field samples were less than 10 μg/l. Nitrate concentration varied between 2.1 to 69.2 mg/l, and EC varied between 1.7 to 15.1 mS/cm. 

BTEX compounds were absorbed with high efficiency in the laboratory test, but their concentrations in wells were found to be negligible. Average concentration of nitrate in the wells was less than water quality guidelines, and had no relation with the direction of movement or depth of water. EC tended to increase in the direction of groundwater movement, but there were no correlations among depth of water, nitrate concentration, and mean of EC.X