Impurities are particles or other objects that cause water to be unclear. When there are no impurities found in the water then it is considered pure with no traces of something that can spoil it inside. Impurities can be in many forms but are generally present as hard organic substances that have detrimental effects in the water. Salt, minerals, bleach, and other contaminants are routinely found in small numbers within water, which makes it more unclean and of less quality. Decomposing animals near water sources such as rivers, streams, or lakes lead to problems of chemical impurities that render the water non-consumable.