Lately our environments have been destroyed by such new things as synthetic detergent. How to use detergent at home can be a decisive factor for decreasing water pollution because living sewage by using detergent at home is the main cause of water pollution. We consumers, therefore, should understand the relation between the chemical ingredients of detergent and water pollution and should choose detergent always taking the kinds of detergent, its washing pewer into consideration. We should also contribute to the protection of out environment by keeping the standard of using amount attached to the products.