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When is water safe to drink? - Mia Nacamulli

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  • 28,484 Questions Answered
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Water is refreshing, hydrating, and invaluable to your survival. But clean water remains a precious and often scarce commodity – there are nearly 800 million people who still don’t have regular access to it. Why is that? And how can you tell whether the water you have access to — whether from a tap or otherwise — is drinkable? Mia Nacamulli examines water contamination and treatment.

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Meet The Creators

  • Educator Mia Nacamulli
  • Director Sarah Sun, Angela Wong
  • Animator Rasita Kaye, Jorge Mejia, Hugo Setyadji
  • Storyboard Artist Rebecca Ko, Nadine Promes
  • Composer Stephen LaRosa
  • Associate Producer Jessica Ruby
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Narrator Addison Anderson
  • See more
Additional Resources for you to Explore
How does water typically get cleaned? Click here to find out. Clean water for everyone is a major global issue. Visit the United Nations site on water. Goal 6 of the Sustainable Development Goals is to ensure access to water and sanitation for all. Visit this link to find out more.

A chemical cocktail in our water? How is that possible? Watch: How Drugs Pollute Our Drinking Water and What's REALLY in Our Drinking Water?

Wondering about exactly what problem water contaminated with sewage could cause? Watch this TED Ed lesson: The Story of Cholera.

Flint, Michigan and lead poisoning became a major news topic in 2014-2015. How did it happen? Watch this.

The CDC has some information on chlorine and drinking water. How much chlorine is too much? Click here to find out about disinfection with chlorine.

What can you do to help keep worldwide water clean? Need inspiration? These two captivating TED Talks about ensuring clean water for all people are a great place to start. Deepika Kurup: A young scientist's quest for clean water and How to make filthy water drinkable: Michael Pritchard.

TED-Ed
Lesson Creator
New York, NY
What is your reaction to hearing the description of “a chemical cocktail” in a water supply? What does this mean? How is this possible?
07/13/2017
Avatar for sherouk elsayed
sherouk elsayed • LESSON IN PROGRESS

water have a combination of different types of chemicals

08/07/2017
Avatar for Lin LI
Lin LI • LESSON IN PROGRESS

It makes me feel unsafe. Though I knew that our drinking water has been through some processes, I barely ask what exact processes are there? Are they really safe for us? Is it possible that while they **** some bad effect, they also bring new risks?

08/10/2017
Avatar for David Chester
David Chester • Petach Tikva, Israel • LESSON IN PROGRESS

It is the proportion of the chemicals that is significant and not the implied variety or cocktail. In other words, it is use of the wrong word.

Many of the proposed treatments are impractical due to their cost and need for installation far from a source of other supplies such as electricity or chlorine tablets. I believe the natural cleaning methods are best such as running the water over a stream having water weeds, and by condensing the moisture from the air in the early morning before it evaporates (dew ).

When discussion the amount of infant deaths it is both heart breaking but simultaneously acceptable because when our own countries were less well-developed (as in Victorian times in the UK), infant mortality rates were similar or worse. So this situation is one of the ways that a country needs to accept as it gathers strength and becomes more mature. (I am sure lots of people will disagree with this philosophy.)

08/13/2017
Avatar for TED MDEFISCH
TED MDEFISCH • Pittsburgh, Pennsylvania, United States • LESSON IN PROGRESS

Yes there are unwanted things in our water, Fluorides which is excessive and industrial waste, it's in toothpaste with a hazardous warning ..not to use more than a pea size and ! Don't swallow. There are priscription drugs ..Are they completely filtered out? There's disinfectant byproducts that can be just as dangerous as bad bugs. Often there is too much chlorine. When in anybodies life did any Gov Health Agency come and test the WATER in our kitchen sinks and bathroom showers? Unless people are dropping in the street there is NO ONE GIVING ANY ATTENTION. So we randomly get sick ,some get sicker ,some die some recover and mostly at times the threat goes away without anyone having a clue ...it was in the water we drank.

08/14/2017
Avatar for sofia torres
sofia torres • COMPLETED LESSON

One in ten people do not know if the water they drink is clean or full of bacteria

08/23/2017
Avatar for Jaron Goh
Jaron Goh • LESSON IN PROGRESS

makes me feel scared that sometimes we might drink waters that are not clean may cause bad affect to us.

09/08/2017
Avatar for Atiq Analily
Atiq Analily • LESSON IN PROGRESS

For me a "chemical cocktail" in water means that there are various particles or chemical component that are unknown and most likely harmful for us in water. This harmful condition of water could have an impact on people especially children and the underprivileged. This is possible when water is not treated properly.

09/09/2017
Avatar for Xin Yin Lee
Xin Yin Lee • LESSON IN PROGRESS

I knew that sometimes our drinking water is not clean an this will affect our health. 'A chemical cocktail' means a combination of substances, especially ones that are harmful when used together. This is possible when the water doesn't treated or filtered properly.

09/09/2017
Avatar for j.g mar
j.g mar • COMPLETED LESSON

weter have a combination

09/09/2017
Avatar for Jia Xuan Ng
Jia Xuan Ng • LESSON IN PROGRESS

Chemical cocktail is a combination of substances, especially ones that are harmful when used together. I feel unsafe when I knew that there are many bacteria and viruses in the drinking water sometimes. Moreover, those bacteria will actually affect our human's health, especially children. Diarrheal disease is unavoidable and this actually causes of death around the world especially children under 5. Undeniably, all of those diseases are possible to happen if people keep drinking unfiltered water.

09/10/2017
Avatar for Ezra Chee
Ezra Chee • COMPLETED LESSON

I feel shocked that we drink this kind of thing everyday. After watching this i feel like water arent save anymore.

09/10/2017
Avatar for Wei Peng Ng
Wei Peng Ng • COMPLETED LESSON

I feel dangerous that drinking water won't always be save and clean. Those diseases will affect to our health specially, malaria and diarrhea. A chemical cocktail means a combination of substances, especially ones that are harmful when used together. This is possible when water is not remedy.

09/10/2017
Avatar for Nanchyi Cheah
Nanchyi Cheah • COMPLETED LESSON

For me, "a chemical cocktail" means that it is a mixture of different chemical and bacteria in the water, which means it could bring diseases or threat to humans who drink it. This is possible if the water is not filtered or treated before serving.

09/10/2017
Avatar for Jessie Tan
Jessie Tan • LESSON IN PROGRESS

I feel bad to those countries that didn't get access to clean water.

09/10/2017
Avatar for Lee Shi Yun
Lee Shi Yun • LESSON IN PROGRESS

Chemical cocktail is the unwanted substances in the water that will actually affect our health. It's dangerous for people to drinking a lot of water with those harmful substances especially kids and patients that have weaker immune system. It's possible to lead to different diseases like diarrhoea and even death.

09/10/2017
Avatar for Thineswari Theyagarajan
Thineswari Theyagarajan • COMPLETED LESSON

For me "a chemical cocktail" in a water supply means not only the sources like leaching, chemical spills and runoffs which cause long-term health effects but also the high-density heavy metals like, chromium and lead and even chemicals like chlorine. I feel very bad and unsafe hearing this as we all are consuming water that has a lot of contaminants which later on can lead to death if there is no any further development. So it's better to take some safety precautions by following the processes which include sedimentation, filtration and disinfection. Apart from that too much turbidity and trace compounds are unsuitable for consumption as it can lead to health issues like cancer, cardiovascular and neurological disease and even miscarriage.

09/10/2017
Avatar for Siau Peh Loo
Siau Peh Loo • LESSON IN PROGRESS

I think "chemical cocktail" is water mixed with different type of chemicals .This is unsafe and it will brings disease such as diearrhea after drinking to it.

09/10/2017
Avatar for ziv hale khong
ziv hale khong • LESSON IN PROGRESS

I feel so unbelieved about this fact when know what is "a chemical cocktail"means, i doubt about this things.Its will effect ours life, might gives us more dangerous disease. A chemical cocktail meaning a combination of substances, we don't know what was affect will going be.

09/10/2017
Avatar for Juliet Hakvoort
Juliet Hakvoort • COMPLETED LESSON

i didn't know that water can be dangerous. I always have healthy water, but some people are killed! Nice people have invented it, to clean water

09/22/2017
Avatar for Diana Ángeles
Diana Ángeles • COMPLETED LESSON

People almost never worry about the effects that water can cause on our health.
Contaminants in water are not always caused by companies, it is by the depserdicios of human activity.

09/24/2017
Avatar for Laydy Muñoz
Laydy Muñoz • COMPLETED LESSON

i would feel unsafe of drinking that water if i hear an expression like that.

09/24/2017
Avatar for Maria Fernanda Vieyra
Maria Fernanda Vieyra • COMPLETED LESSON

Watching this video amazes me a lot about how it is possible that we can drink so much that we do not even imagine.

09/27/2017
Avatar for Maria Fernanda Vieyra
Maria Fernanda Vieyra • COMPLETED LESSON

I find it surprising how it is possible that we take things that we do not even imagine and we know the damage we do

09/27/2017
Avatar for garcia alondra
garcia alondra • LESSON IN PROGRESS

it would be a bit of uncertainty because it is not known very well that it is a chemical cocktail

09/27/2017
Avatar for garcia alondra
garcia alondra • LESSON IN PROGRESS

it would be a bit of uncertainty because it is not known very well that it is a chemical cocktail

09/27/2017
Avatar for Esmeralda Reyes
Esmeralda Reyes • LESSON IN PROGRESS

I knew that sometimes our drinking water is not clean an this will affect our health. 'A chemical cocktail' means a combination of substances, especially ones that are harmful when used together. This is possible when the water doesn't treated or filtered properly

09/27/2017
Avatar for Luis Grace
Luis Grace • COMPLETED LESSON

It is something that at first becomes important of importance however as a person you ask that you have so much poisoned your body without knowing it.
In other words, we do not know that we are actually drinking at times but it is part of our current life, we risk it whether we want it or not. The water has been contaminated for too long so whoever assures us that it is completely pure.

09/28/2017
Avatar for Dulce Moreno
Dulce Moreno • LESSON IN PROGRESS

I knew that sometimes our drinking water is not clean an this will affect our health. 'A chemical cocktail' means a combination of substances, especially ones that are harmful when used together. This is possible when the water doesn't treated or filtered properly.

09/28/2017
Avatar for Hiram Elya Suárez León
Hiram Elya Suárez León • COMPLETED LESSON

The pollution of the industries provokes that since the water will be toxic

09/30/2017
Avatar for Álvaro CB
Álvaro CB • COMPLETED LESSON

Me hace sentir inseguro. Aunque sabía que nuestro agua potable ha pasado por algunos procesos, apenas pregunto qué procesos exactos hay? ¿Son realmente seguros para nosotros? ¿Es posible que mientras que **** algún mal efecto, también traen nuevos riesgos?

10/01/2017
Avatar for maria del rosario martinez lopez
maria del rosario martinez lopez • LESSON IN PROGRESS

water can have chemicals because it is contaminated

10/07/2017 • 
IN RESPONSE TO sherouk elsayed Show the comment
Avatar for ahmad dayem
ahmad dayem • COMPLETED LESSON

It's very scary that we are putting negative items in our bodies. This is the reason why we are hearing so many cases of cancer and various viruses.

10/12/2017
Avatar for Haruka Kasai
Haruka Kasai • COMPLETED LESSON

The phenomenon of chemical cocktail in a water supply causes too much chlorine in the process of cleaning. As a result, water tend to be alkalinity and when it mix one which is acidity, some kind of smokes occur. So my reaction must be negative because the water contained much unnatural chemical is absolutely bad for health. On top of that, it must be strange tasty, I think.

10/17/2017
Avatar for Erika Gómez
Erika Gómez • COMPLETED LESSON

Combination of several substances that may be harmful to health

10/24/2017
Avatar for Len Hogue
Len Hogue • LESSON IN PROGRESS

When I hear that I never wanna drink water again. It gets all the bacteria and kids are dying because of drinking that nasty water that holds bacteria and diseases that other people pasted down the drain.

11/14/2017
Avatar for Dustin Greathouse
Dustin Greathouse • COMPLETED LESSON

humans caused it

11/14/2017
Avatar for DULCE MARIA GUADALUPE
DULCE MARIA GUADALUPE • LESSON IN PROGRESS

It is the proportion of the chemicals that is significant and not the implied variety or cocktail. In other words, it is use of the wrong word.

Many of the proposed *********** are impractical due to their cost and need for installation far from a source of other supplies such as electricity or chlorine tablets. I believe the natural cleaning methods are best such as running the water over a stream having water weeds, and by condensing the moisture from the air in the early morning before it evaporates (dew ).

When discussion the amount of infant deaths it is both heart breaking but simultaneously acceptable because when our own countries were less well-developed (as in Victorian times in the UK), infant mortality rates were similar or worse. So this situation is one of the ways that a country needs to accept as it gathers strength and becomes more mature. (I am sure lots of people will disagree with this philosophy.)

12/02/2017
Avatar for illiane medina vicente
illiane medina vicente • LESSON IN PROGRESS

Sometimes, due to negligence or carelessness, the water is affected which is extremely dangerous because it mixes with different substances and being ingested by a person produces very bad consequences

12/06/2017
Avatar for Lucero Aguilar
Lucero Aguilar • LESSON IN PROGRESS

for me it is the amount of chemicals that they use to filter the water and the amount that stays and is not removed

12/09/2017
Avatar for Jonah White-Wilson
Jonah White-Wilson • COMPLETED LESSON

I agree with that statement because nobody really asks "whats in the water" rather than just drinking it. Although this "chemical cocktail" has some downsides, it does keep our water clean and it is a much better alternative to unclean water.

01/17/2018 • 
IN RESPONSE TO Lin LI Show the comment
Avatar for William Jose Figueira Andrade
William Jose Figueira Andrade • COMPLETED LESSON

The first reaction is alarm but after reading this ********* we can say that it is a mixture of chemicls that are used by companies to desinfect the wáter of pathogenic agents

03/09/2018
Avatar for kaidi tang
kaidi tang • LESSON IN PROGRESS

Our health is exactly threatened by the water with chemical leftover.These compounds can trigger other chemical reactions to form unexpected byproducts.It means that there is no guarantee that our drinking water are absolutely clean and safe after the *********** process.The proper processes required advanced equipments which are highly cost so that there are still a little
sewage in treated water.

07/13/2018
Avatar for Nur Maulia
Nur Maulia • LESSON IN PROGRESS

about the bacteria maybe its can be kill by our immune system... but that chemical cocktail, even our body having a tolerance with the chemical but sometimes all that chemical is buried under vessels and blood. it can be toxic..

07/20/2018
Avatar for Rani Nune
Rani Nune • COMPLETED LESSON

I am aware that there are many things added to water in order to sanitize it, so it was not a complete surprise to hear about the description of a chemical cocktail. However, using the term “chemical cocktail” definitely makes me feel uncomfortable as I perceive it negatively. The terminology suggests that my water could contain unsafe chemicals or excess quantities of certain byproducts that may not be intended to be in the water. A chemical cocktail means that water is not simply water. It is a combination of many chemicals to disinfect the pathogens and microorganisms in the water. These chemicals then release byproducts that further add more chemicals to the water. Although the chemicals are regulated, mishaps occur, and there is no telling when an imbalance can occur. We must simply be aware of the indicators of unsafe drinking water and recognize when water should be further tested to determine its quality.

08/28/2018
Avatar for Professor Aeryn
Professor Aeryn • COMPLETED LESSON

Cl and O3 ~both used together to clean water. Possible if you don't use a filter at home to remove them.

11/13/2018
Avatar for jang hanyi
jang hanyi • LESSON IN PROGRESS

I think 'chemical cocktail' is water with chemicals added to keep water clean. People these days do not go through the process of removing bad germs by solar power or filtering out water to remove sediment as they did in the old days. It is said to add a lot of "chlorine," one of the chemicals. However, too much of this may produce a bad chemical. So, if you don't want to drink "chemical cocktail," you might think it would be better to use the filtration function than to add chemicals.

09/29/2019
Avatar for Kadiann Isaacs
Kadiann Isaacs • COMPLETED LESSON

Water are very dirty some times and some times clean

06/08/2020
Avatar for Jerimayha Genego
Jerimayha Genego • COMPLETED LESSON

When I first think of the word a chemical cock tail I think of dirty.

10/07/2020
Avatar for Zane Dodd
Zane Dodd • LESSON IN PROGRESS

kinda scary cause you have no idea what can be in your water that you drink clean and take baths can have in it

10/21/2020
Avatar for Sydney Hughes
Sydney Hughes • LESSON IN PROGRESS

It was very disgusting to hear about because you know what else could be in water. It’s very unsafe a to drink water that is referred to a chemical cocktail. However, it makes me feel very grateful for the clean water I have access to.

03/03/2021

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About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Mia Nacamulli
  • Director Sarah Sun, Angela Wong
  • Animator Rasita Kaye, Jorge Mejia, Hugo Setyadji
  • Storyboard Artist Rebecca Ko, Nadine Promes
  • Composer Stephen LaRosa
  • Associate Producer Jessica Ruby
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Narrator Addison Anderson
  • See more

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