Water is a precious resource that fulfills one of the most basic human needs، but is still scarce. There are about 800 million people worldwide who do not have access to clean and safe water، contributing to one of the leading causes of death for children under five. Although it's difficult to assess the exact risks of chemically contaminated drinking water، there are several ways to tell our tap water is drinkable.
In TED-Ed's video، "When is water safe to drink?" Mia Nacamuli explains water goes through proper treatment processes that can help reduce the cases of microbial waterborne illnesses.
First، in the sedimentation process، water sits undisturbed، allowing the heavier particles to sink to the bottom. Since the particles are too small to be removed by sedimentation alone، they need to go through a filtration process where gravity pulls the water downward through layers of the sand، and catch the leftover particles in the pores. This prepares water for the final treatment — a dose of disinfectant — that destroys water's living organisms.
The government regulates this process because it has potentially harmful chemical byproducts. If an imbalance of chlorine occurs during the disinfection process، this can trigger other chemical reactions. For example، levels of chlorine byproducts like trihalomethanes could rise، which can lead to pipe corrosion and the release of iron، copper، and lead into drinking water.
Water contamination from these and other water sources، like leaching، chemical spills، and run-offs، have been lined to long-term heart health effects، including cancer، cardiovascular and neurological diseases، and miscarriage.
Disinfectants help make our drinking water safer by removing disease-causing pathogens، but it's still unclear how chemicals in our drinking water can impact our health.
So، how do we tell if our water is drinkable?
First، we have to determine if there is too much turbidity. This refers to the cloudiness or haziness of water، which is caused by a large number of individual particles that tend to be invisible to the naked eye. Turbidity measurement is key to testing water quality.
After the disinfection process، water may still contain trace concentrations of synthetic organic compounds، which if left in water، can lead to taste and odor problems. This is most likely to occur when the raw water source has been badly polluted. High density metals، like arsenic، chromium، or lead، could mean the water is unsuitable for consumption، but these contaminants would not be obvious without a water testing kit، which could confirm the presence of many different contaminants and chemicals.
But if unavailable، we should look out for cloudiness، brown or yellow coloration، a foul odor، or an excessive chlorine smell.
In addition، point-of-use treatment can help eliminate potential contaminants that linger after the disinfection process. Typically، this treatment uses ionization to lower mineral content. Also، absorption filtration is used as carbon strains the water to remove contaminants and chemical byproducts.
Point-of-use is portable، easy to install، and adaptable، which makes it a temporary، but effective، short-term solution.
Previous research has also found an unlikely but helpful ally to clean drinking water — cilantro. In a 2013 study، researchers tested various samples of plants from cacti to flowers، and determined cilantro is the most prevalent and powerful so-called bioabsorbant material in the area. Bioabsorption describe using organic materials (often found in plants) that when dried، could replace the charcoal currently used in filters.
They hypothesize the outer wall structure of the tiny cells that make up the herb can capture metals. The researchers believe ground-up cilantro can be inserted into a tube where water is passed through. The plant will allow water to trickle out، while absorbing the metals، leaving cleaner drinking water.
It's safe to say there are continued developments on water treatment both on a large and small scale. This can help alleviate a lot of unsafe conditions by implementing proper systems where they're needed. Meanwhile، we can pay careful attention to those in place، to prevent further contamination and microbial waterborne illnesses.