All living organisms including humans depend on water to survive. However, the rate of contamination as a result of industrial, agricultural, and chemical waste materials being dumped into the pathways/runways of water bodies, is one of the major environmental challenges impacting humanity.
Water makes up three-quarters of the human anatomy and is the primary means through which the body’s essentials are carried around the body. Water transports blood from one part of the body to another and aids digestion; it also holds and transports electrically charged ions, which form nerve signals that allow the human brain to function.
Unfortunately, despite the importance of water in the body, according to “The Conversation” in 2017 only roughly 64% of Nigerian homes have access to safe drinking water, such as piped water, boreholes, and rainwater collection. The findings also revealed that around 90% of those homes had consumed E. coli-contaminated water at some point, whether from clean or non-clean sources.
Using Lagos as a case study, some aquatic organisms in the lagoon are commercially important as they get to be sold, giving food and cash to residents, both those in the nearby areas and even beyond. The Lagoon has also been responsible for the availability of fish such that the fishes captured here account for over half of Nigeria’s fisheries production, which totals nearly 800,000 metric tons.
Unfortunately, the lagoon also gets a significant amount of pollutants from the state’s manufacturing and municipal operations, including organic and inorganic pollutants that can pose health concerns to fish, shrimp, and crabs, as well as humans who consume them.
In Lagos, there has been a fast increase in cases of dysentery and cholera which can be attributed to the consumption of water that contains chemical and bacterial contamination.
Major factors that have contributed to this contamination however include: lack of proper sewage infrastructure in Lagos and this has been identified as the primary source of pollution.
Another factor that has been identified is the indiscriminate dumping of refuse into water bodies when it is raining. Some sewage also gets washed away by rainwater into open drains and this water then carries pollutants which they deliver to rivers and even the lagoon.
Another factor is sewage from septic tanks (soakaway) which reaches groundwater level and as a result contaminates water in wells and boreholes that are consumed as drinking water.
The effects of these pollutants effects vary depending on the nature and source of the pollutants. While, for example, heavy metals, dyes, and other organic contaminants have been linked to cancer, hormonal imbalances, and other health problems. Dyes, plant and animal medications, personal care product wastes, and petroleum organic pollutants have been identified as some of the organic pollutants that cause major harm directly to aquatic species and indirectly to humans.
High concentrations of heavy metal ions have also been shown to harm cell membranes, alter enzymes involved in chlorophyll formation, and hence lower photosynthetic rate, as well as impair plant reproduction by reducing pollen and seed viability.
Heavy metals as pollutants in water have been known to cause toxicity in humans, and cause minor eye, nose, and skin irritations, severe headaches, stomach aches, diarrhea, hematemesis, vomiting, and dizziness, as well as severe organ dysfunction such as cirrhosis, necrosis, low blood pressure, hypertension, and gastrointestinal distress.
Aquatic life is not left out as heavy metals have been linked to a decrease in crustacean appetite and, as a result, a reduction in body weight in aquatic animals. Also, fishes, shrimps, and crabs, as well as people who eat them, may be exposed to these organic and inorganic chemicals.
Another factor that has been identified is increased quantities of nutrients in water, such as fertilizer runoff, that cause algae to grow at an excessive rate, and when the algae die, bacteria feeding on the dead matter lower the oxygen level in the water, resulting in dead zones where nothing can live.
However, to address water pollution as a key climate change concern, effective wastewater treatment has been identified as a means of protecting the water environment, with a focus on effective, inexpensive, and accessible wastewater treatment methods.
Also preparing to ensure equal access to water, sanitation, and hygiene services (WASH) and also strengthening the government’s efforts to end open defecation and waste disposal in the rain is a major way to escape this nightmare. Also ensuring that rural communities have sustainable water sources should be explored.
Furthermore, the pursuit of sustainable development must include water pollution control strategies that assure proper wastewater treatment prior to discharge into the environment especially from the industrial, agricultural and chemical sectors.
Policies should also be incorporated to ensure that the key perpetrators in environmental issues, such as industries, agro-businesses, and even the general public, are held accountable and educated about the impact of their actions on the present and future environment.
Overall, everyone has a right to pure water, for both domestic and industrial use, and beyond government policies and action, the onus rests on everyone to see that their waste is disposed of properly, so as not to harm other lives.