In a recent scientific article, Latifa Mouhir, professor in the Process and Environmental Engineering Department at the Faculty of Sciences and Techniques of Mohammedia at Hassan II University in Casablanca, along with three other researchers, Sayerh Fatimazahra, Saafadi Laila and Monsif Khazraji, alerted to the dangerousness of hospital effluents, discharged into receiving environments.
Cet article is entitled “Review of hospital effluents: special emphasis on characterization, impact, and treatment of pollutants and antibiotic resistance” antibiotic resistance). It was published in early February in specialized journals.
Its objective is to “improve knowledge on the composition of these effluents and their impact on human health as well as on the environment, by highlighting the different treatment techniques adapted to this type of evacuation, before their discharge into the environment”, explains Professor Mouhir, joined by Médias24.
No specific treatment for hospital effluents
The article starts from an initial observation. “Hospital effluents are directly discharged into collective sewerage networks“, explains Professor Mouhir. “This observation is not not specific to Morocco. These effluents, including in different countries of the world, pass through treatment stations, in the same way as domestic effluents. There is therefore no specific treatment for hospital effluents.
“At the level of wastewater treatment plants, which are rather biological stations, microorganisms ensure the biological treatment of effluents. In the presence of hospital effluents, which are toxic, these microorganisms remain inactive“, continues our interlocutor.
“Hospital effluents, generated on a large scale by healthcare establishments, lead to negative effects on the aquatic environment and human health due to their high organic matter load and the presence of various emerging contaminants. We are starting to have many emerging pollutants, such as disinfectants, drugs, bacteria, viruses and parasites.”
The toxicity of hospital wastewater is 5 to 15 times greater than urban effluent
“These effluents also carry antibiotics which promote the emergence of antibiotic-resistant microorganisms in the environment, which is serious. This resistance, which has become a global issuemanifests itself in different countries and causes the transmission of different infections.”
The article shows that hospitals use a considerable volume of water daily, between 400 and 1,200 litres, depending on the number of beds they have. At the same time, they generate up to 400 l/d of wastewater.
This waste water constitutes a danger for the environment and man, because of its infectious and toxic characteristics. These, whose toxicity is 5 to 15 times greater than urban effluents, contain a wide range of dangerous pollutants, such as pharmaceutical residues and chemical substances, and can be the source of various chemical, biological and and physical, including disease transmission, especially during times of pandemic.
They can also induce the development of a number of dangerous bacteria, which cause the appearance of several water-related diseases, especially in developing countries.
Antibiotic resistance
The article also mentions a excessive and persistent use of antibiotics by hospitals, 30-90% of which are not absorbed by the human system. Residues are therefore discharged into effluents, which in turn accumulate in wastewater treatment systems, creating an environment conducive to antibiotic resistance, a major global concern.
“Certainly, antibiotics play an important role in the prevention and treatment of infections by preventing the essential functions of bacteria. However, the activity of these different antibiotics on bacteria leads to the phenomenon of antibiotic resistance. This is the one of the most serious threats to public health in the world, because it limits the possibilities of treatment of community infections”, explain the authors of this article.
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“This phenomenon was previously limited to clinical settings. But over the years, the massive use of antibiotics has led to the emergence of resistant organisms in the environment, especially in water,” they add. “This resistance has become a major source of mortality around the world, because the number of antibiotic resistant genes has continued to increase.”
“Despite the many risks associated with this wastewater, the legal requirements for its treatment are still insufficient. It is rare to find legislation in this direction or even recommendations for the management of these materials.”
Parameters above the standards authorized by the WHO
In this article, the researchers also focused on the microbiological, physico-chemical and ecotoxicological characterization of hospital wastewater. It shows that the microbiological and physicochemical parameters exceed the standards authorized by the World Health Organizationputting living organisms at enormous risk.
“Given the multiple risks associated with these discharges, source treatment to remove or minimize any pollutants in the environment is necessary. The introduction of these pollutants into water resources and the food system through various pathways is considered to be a serious threat to humans and other organisms.”
“Fortunately, the new hospital construction policy in Morocco take this issue into considerationand the networks are beginning to be separated, between collective sanitation and hospital effluents”, specifies Professor Mouhir.
“Efforts are being made to protect water resources through current treatment methods, involving physicochemical processes such as absorption, advanced oxidation processes and biological processes,” concludes Pr Mouhir.