Determination of Emitted Airborne Microorganisms from a Wastewater Treatment Plant

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Microflora of wastewater is very much vast just like the composition of pollutants. Large amount of microorganisms are found in domestic sewage along with human and animal excreta. Among the microbes determined in sewage and in the air collected at a wastewater treatment plant they contain both saprophytes, potential pathogens and pathogens of the genera Clostridium, Enterobacter,Bacillus, Escherichia, Klebsiella, Mycobacterium, Pseudomonas, Serratia, Staphylococcus, Salmonella, as well as filamentous fungi from genus , Penicillium and Aspergillus.




Microorganisms which are transferred from sewage to air in the form of mainly bioaerosol are prone to some conditions which can increase their growth and development. Some amount die rapidly mainly due to desiccation, exposure to excessively high or low temperatures or are killed by solar radiation. But a few microorganisms have some specific mechanisms which enable them to survive the unfavourable and harsh environmental conditions which could stop their biological activity.

Thus, large counts of  these microbes in air is a major indicator of atmospheric pollution.

Wastewater treatment plants are a source of biological aerosols and they are the location point of source of atmospheric air pollution. However, differences between WWTPs, including, type of technological facilities applied, sewage composition, aeration method, land management and plant capacity thus results in differences in generation of bioaerosols.

highest risk for exposure to biological aerosols are the areas adjacent to aeration chambers because of the high amount of microbiological pollution generated there.

 

Conclusions

Faecal bacteria and other microbes which are the typical living microflaura of sewage, show out the real amount of air pollution degree in and around the plant. This should be monitored well to establish the effects due to which natural environment and human health is being depleted drastically. The main sources of bioaerosol emission at the plant were the grate chamber as well as bioreactor. Large counts of the family  of Enterobacteriaceae bacteria, including pathogenic and opportunistic bacteria and high variety of species found in air samples inside the bioreactor, may indicate that the health of the staff staying for longer periods of time near the bioreactor could be at risk. So suitable methods to reduce the health hazards like covering aeration chambers, reduced aerosol generation helps in more decrease in the numbers of airborne microorganisms in a Bio treatment system plant area and its surroundings. This is much necessary action to be implemented.

 



 

References:

 

https://doi.org/10.1016/j.watres.2018.11.027

 

https://doi.org/10.1016/j.watres.2009.03.050

 

https://doi.org/10.1016/j.jes.2018.02.007

 

Indoor residential chemical emissions as risk factors for respiratory and allergic effects in children: a review

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Health risks from exposure to Legionella in reclaimed water aerosols: toilet flushing, spray irrigation, and cooling towers

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Comments

  1. UnknownNovember 6, 2020 at 7:10 AM

    It is true that people near aeration chambers are at a great risk to biological aerosols. This is a global issue. Well said.

    ReplyDelete
  2. UnknownNovember 6, 2020 at 10:05 AM

    Comment:
    This Airborne microorganisms is really a rare approach and quite studies are being done. Good work by the way

    ReplyDelete

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