TedEd: When is water safe to drink?

A TedEd by Mia Nacamulli

Water is essential for life. But is it always safe to drink? Ten percent of all people cannot be certain that their water is safe because of improper sanitation, hygiene, and protection of water sources. This creates sewage contaminated water, leading to growth of bacteria and viruses. This is very dangerous; diarrheal disease from contaminated water is the main cause of death for children under the age of 5, and microbial disease kills more people than war. However, sanitization can prevent this in 3 steps: sedimentation, filtration, and disinfection. Sedimentation is when water is allowed to sit so that heavier particles drop to the bottom. Then, filtration puts the water through layers of sand that trap small particles in them. Finally, water is disinfected with a combination of chlorine and ozone, which kill pathogens and sanitize the water pipes. However, too much chlorine can result in byproducts that corrode the pipes, releasing metals into the water, so its use is highly regulated. These types of contamination can lead to long-term health effects, which are very hard to identify. Water with high amounts of turbidity, organic compounds, or metals are unsafe to drink. Most of these can't be seen without tests, but odd coloration or odor are indicators that you might need to check. Water contamination tests can help you make sure, and point-of-use filters can help you solve any water contamination. These devices often use ionization and activated carbon filters to clean water. They are also easy to install and move around. Hundreds of millions of people don't have access to clean water. But implementing and repairing systems can help alleviate the strain.