Risks to Public Health from Sewage Treatment: An ENV 407 Report

This report, prepared for ENV 407, examines the public health risks stemming from sewage treatment operations. It identifies two primary hazards: liver disease and occupational lung disease, both of which disproportionately affect workers in sewage treatment facilities. Liver disease is linked to chronic exposure to environmental chemicals and alterations in liver proteome, while lung diseases arise from inhalation of noxious substances. The report provides recommendations for minimizing these risks, including promoting basic hygiene, providing personal protective equipment, offering comprehensive training, and establishing safe working systems. The conclusion emphasizes the importance of implementing these strategies to reduce exposure to harmful chemicals and protect the health of sewage treatment workers.

Running head: HEALTHCARE
Hazardous waste management
Name of the Student
Name of the University
Author Note

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Introduction- Sewage treatment refers to the procedure of eliminating contaminants
from the wastewater generated in households and industries. Primarily, chemical, physical
and biological procedures are employed for the removal of contaminants that help in the
generation of treated wastewater, which is non-toxic enough for release into the surroundings
(Pronk et al., 2015). One common by-product of sewage treatment is slurry, commonly
referred to as sewage sludge that needs to be further treated, prior to its safe disposal or
incorporation to the land. Time and again it has been found that sewage treatment comprises
of five stages namely, pre-treatment, primary treatment, secondary treatment, tertiary
treatment, and fourth treatment (Chiu et al., 2016). This essay will elaborate on two risks or
hazards to public health that arise from sewage treatment and will also discuss steps to
minimise or eliminate the risks.
Public health threats- Owing to the fact that urine and faeces from both animals and
humans carry several illness causing organisms, treated wastewater poses health problems.
One common public health threat that affects people working in sewage treatment facilities is
liver disease. It has been found that chronic exposure of people to the environmental
chemicals present in wastewater creates an impact on liver physiology. On investigating the
impact of these chemicals on liver, Filis et al. (2019) found an increased amount of
polycyclic aromatic hydrocarbons (PAHs) and comparatively less amount of polychlorinated
biphenyls (PCBs) amid males. Moreover, this exposure also creates an impact on
detoxification and xenobiotic response and bring about an alteration in lipid dynamics and
cancer-related pathways, thus increasing the likelihood of people to suffer from liver disease
due to sewage sludge exposure. Abnormalities in the liver due to sewage exposure can also
be accredited to the fact that sewage sludge results in significant alteration in the liver
proteome, in a sex-dependant fashion. Some proteins that have been identified in the sewage
water treatment affected spots comprise of detoxification enzymes, fatty acid oxidation

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enzymes, and important plasma-secreted proteins. An increase in transferrin and albumin
protein also affect liver function, thus triggering the onset and progress of hepatic diseases
(Filis et al., 2015).
Another public health threat is occupational lung disease. These lung diseases occur
due to prolonged exposure of the workers to particular irritants that are inhaled during
respiration, and the impacts persist, even after the exposure terminates. Chandra and Arora
(2018) found that despite the utilisation of different technologies like e Upflow Anaerobic
Sludge Blanket (UASB), Sedimentation, Fluidized Aerobic Bioreactor, and Trickling Filters,
workers employed in sewage treatment plants are continuously exposed to bacteria having
inflammatory potential. Noxious substances commonly include ammonia, carbon monoxide,
bioaerosol, hydrogen disulphide, and methane and increase the prevalence and incidence of
influenza like symptoms, sore throat, wheezing, cough, and production of sputum. Some of
the other common lung ailments reported by the workers are namely, lower airway
symptoms, chronic bronchitis, asthma, chronic phlegm, dyspnoea, and nasal catarrh. The
same has been confirmed by Haleema, Bhargava and Nirgude (2019) who found that sewage
treatment plant workers have forced expiratory volume with mild restriction, Moreover, they
also manifest signs and symptoms of small airway obstruction. Apart from the
aforementioned symptoms, impact of sewage exposure on the lungs can also be associated to
reports of cough with sputum, breathlessness, loss of consciousness, and blockage in the
airways. The prevalence of lung disorder can be accredited to lack of personal protective
equipment and the non-existence of sufficient barricades for preventing contact with clarifier
tank and anaerobic sludge reactor. Tuberculosis is another lung disease commonly reported
by people working in sewage treatment plants and occurs due to their chronic and toxic
exposure to bioaerosols and chemicals that are generated during the treatment process

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(Chandra & Arora, 2019). This results in adverse chronic morbidity profile of the workers
and if left untreated, can eventually leaf to death of the affected person.
Recommendations- Taking into consideration the fact that workers who come in direct
contact with wastewater are at an increased risk of suffering from several diseases, there is a
need to implement preventive strategies. Basic hygiene practices must be taught to all people
working in sewage treatment plants. They need to be educated about the importance of
washing their hands with water and soap, immediately before and after being exposed to
sewage (Zolnikov, 2018). They will be advised not to chew tobacco or smoke while working
in the plants. They will also be suggested to remove soiled clothes and have meals at
designated regions that is free of any household wastewater. Efforts need to be taken by the
government to distribute free personal protective equipment for all people working in sewage
treatment plants. These commonly include goggles, protective face shields and masks,
waterproof gloves, rubber boots, and liquid repellent coveralls, all of which will prevent
direct exposure to wastewater (Wright et al., 2019). Moreover, all workers must be provided
adequate training for disease prevention. These training sessions must focus on steps for
following hygiene, disposal of personal protective equipment, and handling of wastewater.
They will also be encouraged to immediately search for medical attention on exhibiting any
signs or symptoms of lung problems or other health abnormalities. The employers must also
ensure the presence of safe working system and encourage an environment of cooperation
and consultation. Supporting occupational immunisation programs will also be of great help
to the workers and prevent their likelihood of suffering from adverse health outcomes.
Providing appropriate warning and labelling signs and ensuring the presence of precise
procedures for reporting of adverse incident is also imperative.
Conclusion- Thus, it can be concluded that sewage treatment helps in elimination of
hazardous wastes and chemicals from water. Despite the fact that the removal of

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contaminants helps in reuse of the water for different purpose, people who are employed in
sewage treatment plants are susceptible to a range of disease like liver ailment and lung
disorders. Direct exposure to the harmful chemicals in sewage increases rates of mortality
and morbidity amid the workers. Thus, it is essential for the government to implement
strategies that can reduce rates of exposure, with the aim of decreasing the health hazards and
risks.

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