Chlorine and Iodine Tablets
You can also take chlorine tablets with you, which are an effective means of destroying bacteria as well as viruses. Iodine is also an effective method of purifying your water, and you usually have to let the tablets dissolve for as long as 30 minutes, before the water is safe for drinking.
A lot of shops in the big cities in Mexico sell chemical water purification systems, which are devices in which you pour the water, and then add chemicals that purify the water for safe drinking. Common chemicals used in this system are potassium permanganate and chlorine dioxide. Potassium permanganate is a chemical that softens water, and chlorine dioxide disinfects water and destroys organisms and bacteria. The one drawback with chemical purification is that it can take several hours before the water is fully treated.