It’s never the end!

Good evening and thank you so much for following my blog posts for the past 12 weeks. Water pollution is indeed an important issue and I would like to use this final post to summarise whatever I covered.

For the first half of the semester, I managed to explore the different types of water pollution, with highlights such as water-borne pathogens, heavy metals and micro-plastics. After which, I explored a case study, that of the Minamata disease, which highlighted the harmful effects of methyl-mercury. Thereafter, we explored COVID-19 and its effects on water quality and pollution. We finally ended off the whole “dive” at home, by exploring how Singapore managed its water resources.

However, I would like to emphasise that despite this blog coming to an end, our efforts to prevent water pollution should never cease. Let’s do our best to preserve water quality, not only for humans, but other living things on the planet as well.

Water Pollution in Singapore – How is it managed?

“Singapore is a country with limited water resources, and it is essential for its water quality to be carefully regulated” (NEA, n.d.). In Singapore, the statutory board in charge of water quality and regulation of water pollution is the National Environment Agency, abbreviated as NEA. The water that belongs to the sewage systems, as well as inland water bodies such as reservoirs and also coastal areas surrounding Singapore, are all managed by NEA (NEA, n.d.).

In Singapore, the main sources of water pollution include industrial effluent and domestic wastewater (NEA, n.d.). Industrial effluent contains chemical and organic pollutants, while domestic wastewater contains mainly organic pollutants, including both suspended and dissolved solids (NEA, n.d.). To keep Singapore’s water clean, soil pollution is also taken into account, as pollutants in the soil can enter the water system as run-off or groundwater (NEA, n.d.). For example, only approved pesticides can be used to control termite populations (NEA, n.d.).

Singapore’s wastewater, whether industrial or domestic, are directed into sewage systems for treatment. “Singapore’s public sewerage system serves all industrial estates and almost all residences” (NEA, n.d.). The Public Utilities Board, otherwise abbreviated as the PUB, regulates the sewage system, as well as the treatment and discharge of industrial wastewater into public sewers (NEA, n.d.). It is mandatory in Singapore to discharge all wastewater into the public sewage system (NEA, n.d.). If this is not possible, according to NEA (n.d.), the industrial wastewater must be treated to specific standards before being discharged into a sewer or watercourse. There are also measures in place, such as pH-monitors and shut-off control systems, to regulate and control pollution from industries that generate large amounts of acidic effluents (NEA, n.d.).

As for both inland water bodies and coastal waters, the water quality is also regularly monitored. The monitored parameters include pH, dissolved oxygen, suspended solids, ammonia, sulphide, metals, bacteria and carbon (NEA, n.d.). Of course, this list is not exhaustive and other physical and chemical properties/parameters are also monitored to measure water pollution (NEA, n.d.).

Overall, Singapore has put in place technology to monitor water quality and also regulate water pollution. In a country with limited water resources, it is essential that we ensure minimal water pollution!

References:

NEA. (n.d.). Water Quality. National Environment Agency. https://www.nea.gov.sg/our-services/pollution-control/water-quality/keeping-our-water-clean

NEA. (n.d.). What are the sources of water pollution in Singapore? National Environment Agency. https://va.ecitizen.gov.sg/CFP/CustomerPages/NEA_google/displayresult.aspx?MesId=1069761

COVID-19 – A placebo

In my previous blog post, I highlighted how COVID-19 might be a panacea to water pollution. This comes with the decline of tourism activities, as seen in the case of beaches and coastal areas in Ecuador. Other than that, my blog post also covered how the hiatus of industrial activities helped to alleviate water pollution in the Damodar River in India. However, despite these examples of how COVID-19 has helped with water quality and pollution issues, we have to look at the whole matter from another perspective. In other words, we have to also analyse how COVID-19 contributed to and worsened water pollution.

First and foremost, COVID-19 has actually worsened contamination of water bodies, by increasing use of microscopic substances. This comes with an increase in the usage of micro-plastics and other chemical/healthcare products such as pharmaceuticals and disinfectants. As reiterated in Manoiu et al. (2022), the negative impacts [of COVID-19] on water bodies include contamination of the said water bodies with micro-plastics, pharmaceuticals and disinfectants. This is also coupled with contamination of the virus itself, which might have leaked from hospitals and sewage treatment plants (Manoiu et al., 2022). These microscopic substances may cause significant impacts on the environment or even human health.

Other than these chemicals which are mostly microscopic in nature, there are also many other “larger” products used during the pandemic that exacerbated water pollution. According to Manoiu et al. (2022), the disposal of sanitary consumables, such as masks, gloves, wipes,  protective suits and safety shoes, which were used for personal protection and medical purposes, causes significant harm on animals. Animals can accidentally swallow the masks or get tangled in their elastic cords (Manoiu et al., 2022). In Bangladesh, 50% of online survey respondents declared that they have dumped their used tissues, masks, gloves and household waste into water bodies (Islam et al., 2021, as cited in Manoiu et al., 2022). In China and Iran, the disposal of contaminated wipes, masks and gloves also pollute the water bodies (Poursadeqiyan & Bazrafshan, 2020, as cited in Manoiu et. al., 2022). Hence, in addition to chemicals at the microscopic level, increase in usage of consumables at the macroscopic level, due to COVID-19, can also cause detrimental effects on water systems.

In conclusion, I argue that COVID-19 should not be seen as a panacea to water pollution issues. The positive effects of COVID-19 on water pollution are temporary and is nothing but an illusion. If humans take no initiative, then even if there was a temporary “solution” to the issue, it is nothing but a placebo.

References:

Manoiu, V.-M., Kubiak-Wójcicka, K., Craciun, A.-I., Akman, Ç., & Akman, E. (2022). Water quality and water pollution in time of covid-19: Positive and negative repercussions. Water, 14(7), 1124. https://doi.org/10.3390/w14071124

COVID-19 – A panacea to water pollution?

COVID-19 began in December 2019, and till today, it is still running rampant. The coronavirus has caused many countries and governments to restrict unnecessary activities, be it business or leisure. Governments implemented social distancing and lockdowns of entire cities, all to prevent the spread of the virus. New vaccines were also developed to counter the virus, with the State encouraging all citizens to take the shot if possible. Wearing of masks were also made mandatory in some countries, such as Singapore.

There are many articles, both online and offline, that has talked about how COVID-19 has helped to “heal” the Earth. This is because of how there is less air travel, and also because of how anthropogenic activities are restricted. However, is COVID-19 really a panacea to surmount the obstacles that Man has caused? Or is it just a placebo? This blog post will evaluate how the COVID-19 pandemic is a solution or strategy to mitigate water pollution issues.

“Leisure and business activities on beaches and in ports have restricted direct and indirect contamination from, for example, plastics, hydrocarbon spillage, microbiological loads, and noise levels. This has led to temporarily improved environmental conditions, and … beaches having conditions closer to Marine Protected Areas” (Ormaza-Gonzaìlez et al., 2021). As can be seen from the statement, COVID-19 may be argued to have positive impacts on water pollution. In the same article by Ormaza-Gonzaìlez et al. (2021), in which coastal areas and beaches in Ecuador were studied, it was found out that due to the COVID-19 pandemic, many marine species returned and there were also reduction in noise levels and environmental pollution. Hence, it can be argued that COVID-19 has helped to alleviate water pollution as it reduced tourism activities, as can be seen from how “populations residing in Salinas, Manta, and Galapagos have clearly noticed a positive change in the quality of beaches due to the absence of tourists caused by COVID-19” (Ormaza-Gonzaìlez et al., 2021).

Other than the case of Ecuador, COVID-19 has also helped with water quality in the Damodar River, which is located in India. Not limited to India, “degradation of aquatic environment, river water quality, pollution and health [and] river ecosystem services … has been amplified due to rapid urbanisation, industrialisation and execution of various developmental activities” (Chakraborty et al., 2021). Also in general, “the majority of the large world rivers are polluted by anthropogenic activities such as non-degradable agriculture fertilisers and untreated industrial sewage discharge into rivers” (Chakraborty et al., 2021). As such, when the pandemic hit in India, the “complete stopping of activities of industries, mining [and] commercial sectors highly helped to improve water quality by [reducing] … waste effluents directly discharged [in]to the [Damodar River]” (Chakraborty et al., 2021). Hence, it can be seen how lockdowns and restriction of anthropogenic activities, both caused by the pandemic, helped to improve river water quality in India’s case.

Overall, COVID-19 has helped to “dilute” water pollution issues. However, is it really a panacea with no loopholes? In the next blog post, I will be covering how COVID-19 is nothing but a placebo. See you!

References:

Chakraborty, B., Bera, B., Adhikary, P. P., Bhattacharjee, S., Roy, S., Saha, S., Ghosh, A., Sengupta, D., & Shit, P. K. (2021). Positive effects of covid-19 lockdown on river water quality: Evidence from River Damodar, India. Scientific Reports, 11(1). https://doi.org/10.1038/s41598-021-99689-9

Ormaza-Gonzaìlez, F. I., Castro-Rodas, D., & Statham, P. J. (2021). Covid-19 impacts on beaches and coastal water pollution at selected sites in Ecuador, and management proposals post-pandemic. Frontiers in Marine Science, 8. https://doi.org/10.3389/fmars.2021.669374

Case Study: The Minamata Disease

Minamata is a small town located in the Kumamoto Prefecture on Kyushu Island in southern Japan (see Figure 1). Minamata has abundant fishing resources. However, it also hides a dark past…

Figure 1: Location of Minamata in Japan (Source: Author’s own)

The Minamata disease was first “discovered”, or rather detected, in Minamata, Japan, and hence gives rise to the name of the disease (Harada, 1995). First encountered in May 1956, it is a disease involving methyl-mercury (MeHg). People who ingested fish and shellfish contaminated by MeHg were suffering from neurological disorders, of which some symptoms include tremors in their limbs, difficulty walking and lost of sight and hearing (Kugler, 2022). Some people even lost their mind and went crazy, shouting uncontrollably (Kugler, 2022). Figure 2 shows a patient suffering from the Minamata disease.

Minamata Disease

Figure 2: A patient suffering from the Minamata disease (Source: https://journalsofindia.com/minamata-disease/)

The cause of the Minamata disease was found out to be consumption of seafood, including fishes, which contain high concentrations of mercury in them, at 5.61 to 35.7 ppm (Harada, 1995). Attention was immediately turned towards a nearby chemical factory, which manufactured acetaldehyde, otherwise known as the Chisso Corporation (CHE, n.d.). The mercury waste produced by the corporation was bio-transformed by bacteria in the water into MeHg, or organic mercury, that bioaccumulated and biomagnified in the muscle of fish (CHE, n.d.). Over two thousand people died, and thousands more experienced crippling injuries, all of which were tied to MeHg poisoning and the Minamata disease (CHE, n.d.).

I included this case study because it is highly relevant to water pollution, be it the pollution of heavy metals or even the biomagnification of toxic substances. Other than that, it is also important for us to understand the political ecology behind this disaster. Namely, these are the politics of economic power and the uneven environmental impacts caused by the Chisso Corporation.

With regards to the politics of economic power, the Chisso Corporation itself held huge power, and only stopped dumping mercury into the Minamata Bay in 1968 (Kugler, 2022). By then, many people have already suffered from the Minamata disease. The Chisso Corporation had also denied any charges that it had something to do with the Minamata disease, and nothing was changed in the initial years.

The environmental impacts of the Minamata disease was also uneven. It was only when the people of Minamata protested in 1959 that these people managed to get some compensation (Kugler, 2022), while most of the corporation went unscathed. There were uneven impacts caused by these chemical wastes, with foetuses and children suffering the most. The definition of the Minamata disease was also too “strict”, that not everyone met the criteria of being compensated (Kugler, 2022). This again is linked to political ecology, in how knowledge is framed differently depending on the audience and intent.

Overall, water pollution can be seen as both a political issue and also an environmental issue. It can cause many social and economic impacts, and it is important for us to dive into mitigating and solving these problems. See you soon!

References:

CHE. (n.d.). Mercury: The Tragedy of Minamata Disease. Collaborative on Health and the Environment. https://www.healthandenvironment.org/environmental-health/social-context/history/mercury-the-tragedy-of-minamata-disease

Harada, M. (1995). Minamata disease: Methylmercury poisoning in Japan caused by environmental pollution. Critical Reviews in Toxicology, 25(1), 1–24. https://doi.org/10.3109/10408449509089885

Kugler, M. (2022, Feburary 19). The Minamata Disaster and the Disease That Followed. verywellhealth. https://www.verywellhealth.com/minamata-disease-2860856

Heavy metals – another huge matter…

Heavy metals have no specific definition, but are often defined as “a naturally occurring element having a high atomic weight and high density” (Masindi & Muedi, 2018). Examples of heavy metals include arsenic, lead, cadmium, nickel, mercury, chromium, cobalt, zinc and selenium (Masindi & Muedi, 2018). Heavy metals are often given loads of attention as they are extremely toxic, even at low concentrations or trace amounts (Masindi & Muedi, 2018). Often, heavy metals end up in water bodies as pollutants,  after being discharged untreated from industries and factories (Masindi & Muedi, 2018).

Heavy metals are toxic substances that accumulate in the bodies and tissues of organisms (Masindi & Muedi, 2018). Heavy metals have a huge impact on the environment. For example, when accumulated in soil and water, it passes and magnifies along the food chain (Masindi & Muedi, 2018) as the plant absorbs it as “nutrients”, which itself is then consumed by animals in higher trophic levels. The organisms at the highest trophic level suffers the most from the bioaccumulation of these heavy metals.

Different heavy metals causes different health impacts on humans. One example we would turn to examine in subsequent blog posts is the Minamata disease, which involves mercury poisoning. The blog post will highlight the significance and urgency of water pollution issues, with focus on the heavy metal mercury.

References:

Masindi, V., & Muedi, K. L. (2018). Environmental contamination by heavy metals. Heavy Metals. https://doi.org/10.5772/intechopen.76082

Ocean acidification – not so basic…

Marine pollution may take place in the form of ocean acidification. Ocean acidification has become an urgent issue in recent years, especially since the Industrial Revolution began (NOAA, n.d.). Since then, the pH level of ocean surface waters has dropped by 0.1 (NOAA, n.d.). As the pH scale is logarithmic, a 0.1 drop in pH level actually corresponds to a 30% increase in acidity (NOAA, n.d.). The rapid reduction in the ocean’s pH level over a short period of time has “serious consequences for the marine food chain” (Lee, 2019) and also the lives of calcifying organisms that depend on carbonate ions in the ocean (NOAA, n.d.).

Ocean acidification is essentially caused by the “absorption of large amounts of carbon dioxide” from the atmosphere (Lee, 2019). These carbon dioxide are produced and released into the atmosphere from the burning of fossil fuels and also deforestation (Lee, 2019), and possibly other land use changes. The dissolved carbon dioxide sets off a series of chemical reactions which increases the amount of hydrogen ions in the ocean (NOAA, n.d.). As the amount of dissolved hydrogen ions in the ocean increases, the ocean’s pH level decreases.

The series of chemical reactions have negative impacts on calcifying organisms living in the ocean. As carbon dioxide dissolves into the seawater, water combines with it to form carbonic acid (Figure 1), a weak acid that dissociates to form hydrogen ions and hydrogen carbonate ions (NOAA, n.d.), as shown in Figure 2. The hydrogen carbonate ions exists in an equilibrium with hydrogen ions and carbonate ions. When the concentration of hydrogen ions increase, the equilibrium shifts left to favour the formation of hydrogen carbonate ions, causing a drop in the concentration of carbonate ions and hydrogen ions. This drop in carbonate ions affects the calcifying organisms, which require carbonate ions to build their shells and skeletons. As less carbonate ions become available for these organisms’ usage, the shells or even skeletons of these organisms may begin to dissolve and become less defined (NOAA, n.d.).

Overall, air pollution and greenhouse gas emissions, which results from burning of fossil fuels, deforestation and other land use changes, have a negative impact on the ocean as it causes acidification. This acidification affects our biodiversity such as calcifying organisms. There is a rising urgency of this issue as we dive into water pollution.

References:

Lee, A. E. (2019, January 31). Marine Pollution: Ocean Acidification. International Marine Mammal Project. https://savedolphins.eii.org/news/marine-pollution-ocean-acidification

NOAA. (n.d.). Ocean Acidification. National Oceanic and Atmospheric Administration. https://www.noaa.gov/education/resource-collections/ocean-coasts/ocean-acidification

Eutrophication and its disastrous consequences

Sorry for the late post as I was busy preparing for an interview. But let’s get diving again, into today’s topic on eutrophication!

Nutrients are essential for living things to survive and carry out day-to-day activities. However, too much nutrients can lead to disastrous consequences, especially for living things, such as fishes, in freshwater bodies. This process, known as eutrophication, occurs when too much nutrients end up in a water body. “Harmful algal blooms, dead zones and dead fishes” are all negative impacts caused by eutrophication (NOAA, n.d.).

To understand more about eutrophication and its causes, you may want to watch the video that I embedded in this blog post (see Video 1). It all begins when chemicals, such as nitrates and phosphates, are discharged from land into water. In some cases, these chemical runoffs comes from fertilisers used in agriculture, or even detergents. Once these chemicals, or “nutrients”, reach the water body, it causes algae to reproduce and grow in numbers quickly. This is the beginning of a vicious cycle…

Once there is an algal bloom, the algae blocks out the sunlight and prevents freshwater plants from photosynthesising. This causes a decrease in oxygen levels and also the death of these plants. Once the algae dies too, its organic matter sinks to the bottom of the freshwater body, a lake, for example. It then accumulates with the decaying matter of the aquatic plants. Bacteria and other decomposers then break down these organic matter, with an excessive consumption of oxygen, depleting oxygen levels. More nutrients are then returned back into the water body, causing further algal growth. Concurrently, toxic substances such as hydrogen sulphide and ammonia are produced. Finally, when the rate of consumption of oxygen by the bacteria (to decompose the organic matter) is higher than the rate of oxygen replenishment, an anoxic (absence of oxygen) environment is produced in the lake, killing the other living things.

Video 1: What is eutrophication? (Source: FuseSchool – Global Education, on YouTube)

Indeed, eutrophication is disastrous and we should learn how to discharge our (chemical) wastes correctly. This is to reduce the negative implications caused by eutrophication and its harm to the environment.

References:

NOAA. (n.d.). What is eutrophication? National Oceanic and Atmospheric Administration. https://oceanservice.noaa.gov/facts/eutrophication.html

Oil spills and its catastrophic impacts

You probably have heard about oil spills being a prominent disaster. Indeed, oil spills are major catastrophic events that threaten marine environments. They are a major form of marine pollution, and sometimes, occur even in freshwater.

Quoting the National Oceanic and Atmospheric Administration (NOAA) (n.d.), oil spills are most often “caused by accidents involving tankers, barges, pipelines, refineries, drilling rigs and storage facilities”. Most of the spilt oil spreads out rapidly to form a thin layer of oil slick (NOAA, n.d.). However, in rare cases, oil that has heavier components may sink (NOAA, n.d.).

Oil spills have a huge, negative implication on the environment. In and on the ocean, and even on beaches and shorelines, oil spills “can be very harmful to marine birds, sea turtles and mammals, and also can harm fish and shellfish” (NOAA, n.d.). In the case of mammals, oil destroys the insulating abilities of their fur (NOAA, n.d.). Oil can also damage the water-repelling abilities of a bird’s feather (NOAA, n.d.). Many animals also swallow oil accidentally when cleaning themselves or eating prey that is coated with oil (NOAA, n.d.). Fish and shellfish can also ingest oil, which changes reproduction rate and growth rate, and may even cause death (NOAA, n.d.). In turn, this leads to a decline in sources of (sea)food for humans.

As can be seen from Figures 1 and 2, oil spills, such as these caused by the explosion of an oil rig (the Deepwater Horizon in this case), can lead to detrimental effects on the marine environment. Figure 1 shows brown pelicans that were captured to be cleaned. The oil spill caused by the explosion of the Deepwater Horizon had coated the birds’ feathers with oil. Figure 2 shows a photograph of the oil rig’s explosion. Figure 3 shows the extent and widespread impact of the spill on the Gulf of Mexico.

Figure 1: Brown pelicans coated with oil from the Deepwater Horizon oil spill (Source: https://www.britannica.com/science/oil-spill)

Figure 2: Explosion of the Deepwater Horizon (Source: https://www.britannica.com/event/Deepwater-Horizon-oil-spill)

Figure 3: Areal extent of the Deepwater Horizon oil spill (Source: https://www.britannica.com/event/Deepwater-Horizon-oil-spill)

To conclude, this week’s blog post has done a quick summary of oil spills. I focused on the environmental and ecological impact of oil spills and also its causes. Next week, I will move on and explore freshwater pollution, especially those caused by chemical runoffs into rivers. The blog post will also cover eutrophication and bioaccumulation (and biomagnification). Dive in!

References:

Britannica. (n.d.). Deepwater Horizon oil spill. Britannica. https://www.britannica.com/event/Deepwater-Horizon-oil-spill

Britannica. (n.d.). Oil spill. Britannica. https://www.britannica.com/science/oil-spill

NOAA. (n.d.). Oil spills: A major marine ecosystem threat. National Oceanic and Atmospheric Administration. https://www.noaa.gov/explainers/oil-spills-major-marine-ecosystem-threat

Waterborne diseases and its “politics”

“Safe and readily available water is important for public health, whether it is used for drinking, domestic use, food production or recreational purposes. Improved water supply and sanitation, and better management of water resources, can boost countries’ economic growth and can contribute greatly to poverty reduction” (World Health Organization, 2019).

The importance of safe drinking water is irrefutable. In 2010, the UN General Assembly explicitly acknowledged and recognised that everyone should have the right to safe drinking water and also clean water for sanitation and other uses (World Health Organization, 2019). However, despite its importance and significant role in our daily lives, our drinking water is still heavily polluted.

The most common implication of unsafe drinking water is waterborne diseases. “Waterborne diseases are usually caused when a person drinks, bathes in, washes with or prepares food with water that has been contaminated by bacteria, viruses or parasites, usually from human or animal waste” (World Vision, 2021). According to the United Nations Department of Economic and Social Affairs (UNDESA) (2014), every day, 2 million tons of sewage, effluents and wastes are discharged into the world’s waters. Even more shockingly, annually, more people die from unsafe water than from violent events such as wars (UNDESA, 2014). Linking back to human health, contaminated, polluted water, coupled with poor sanitation, are linked to transmission of diseases such as cholera, diarrhoea, hepatitis A, and typhoid, among many other diseases (World Health Organization, 2019). Each year, unsafe water causes about 1 billion people to become ill (NRDC, 2018).

Waterborne diseases are usually caused by pathogens such as bacteria and viruses (NRDC, 2018). Diarrhoea is an example of such an illness. Although easy to deal with in clean, sanitary conditions, it should be understood that many developing regions in the world still has no access to clean water, thus making diarrhoea hard to deal with.

Waterborne diseases are also increasingly transboundary and political. An interesting case study that I would like to point out in this blog post is that of the 2010 Haiti cholera outbreak. In 2010, nine months after a deadly earthquake struck Haiti, a cholera outbreak occurred. The media portrayed the epidemic as caused by the earthquake (Piarroux, 2011). However, this was not true as it was admitted by the UN years later that the outbreak could have been caused by Nepalese troops who were in Haiti for peacekeeping (Sidder, 2016). Surprisingly, it was already suspected in Piarroux (2011) that “a rumor held recently incoming Nepalese soldiers responsible for importing cholera”. Before I move on, it should be recognised that cholera has not occurred in Haiti for more than a century (Piarroux, 2011).

What happened in reality is shocking and political. In fact, the United Nations (UN) camp which hosted these Nepalese troops was discovered to have discharged wastes into the nearby Meille River (Sidder, 2016). Just not long before the troops arrived at Haiti, Nepal was experiencing a cholera outbreak too (Piarroux, 2011). After arriving in Haiti, the virus ended up in the river because the wastewater was untreated. Subsequently, as this river is the primary source of water for the people of Haiti and also because they have no treatment options for the water, the virus ended up causing a massive (and messy) outbreak. The UN, a supranational organization, to maintain its credibility and reliability, probably did not want to admit to being the cause of the epidemic initially. Overall, this case study has shown us how waterborne diseases can be transboundary (happening across two or more nations) and also political (who controls the knowledge and media) at the same time.

References:

Denchak, M. (2018, May 14). Water Pollution: Everything You Need to Know. NRDC. https://www.nrdc.org/stories/water-pollution-everything-you-need-know

Piarroux, R. (2011). Understanding the cholera epidemic, Haiti. Emerging Infectious Diseases, 17(7), 1161–1168. https://doi.org/10.3201/eid1707.110059

Sidder, A. (2016, August 19). How Cholera Spread So Quickly Through Haiti. National Geographic. https://www.nationalgeographic.com/science/article/haiti-cholera-crisis-united-nations-admission.

United Nations Department of Economic and Social Affairs. (2014, October 23). Water Quality. International Decade for Action ‘WATER FOR LIFE’ 2005-2015. https://www.un.org/waterforlifedecade/quality.shtml

World Health Organization. (2019, June 14). Drinking-water. World Health Organization. https://www.who.int/news-room/fact-sheets/detail/drinking-water

World Vision. (2021, July 6). Waterborne disease facts and how to helpWorld Vision. https://www.worldvision.ca/stories/clean-water/cholera-waterborne-disease-facts