Dish spots caused by lack of phosphates in detergent

Over the last few months, nearly everyone with a dishwasher has noticed that their dishes and glassware have been coming out more spotted and cloudy than before. The cause of this problem was recently discovered. On July 1, 2010, all dishwasher detergent manufacturers voluntarily eliminated phosphates from their products in response to 16 states in the United States banning phosphates from dishwasher detergents, according to a news release from the city.

Phosphates helped the cleaning process, but were banned due to their negative effect on the environment. One of the ways the phosphates helped was to eliminate or reduce lime scale inside a dishwasher in hard water areas.

Hard water refers to the natural mineral content in water -- comprised mostly of calcium, with some iron and manganese. It is commonly measured in grains per gallon (gpg).

Most detergent manufacturers say that any water with hardness greater than 10.5 gpg is considered very hard.

In the city of Fort Scott, the water has an average hardness of 12 gpg. Under typical conditions, the majority of these minerals will stay in solution. However, in the high heat of a dishwasher, boiling pot, coffee pot, etc. the minerals tend to come out of solution and deposit onto surfaces.

The minerals are left behind as the water evaporates. This is commonly called lime scale or hard water scale. This inconvenience is now more pronounced on dishes because of the elimination of phosphates in dishwasher detergents.

The phosphates helped keep minerals "bound up," or in solution, so that they are not easily deposited on dishes.

Local hardware stores sell a dishwasher additive that helps remove the hard water scaling. Any product with a citric acid base seems to work well, the release said.

Another practice that can help is turning off the heated drying cycle on your dishwasher and allowing the dishes to air dry. Hand washing dishes will also eliminate the problem, the release said.

Dishwashers are not causing the problem and water provided by the city continues to be safe and "of excellent aesthetic quality," the release said.

This problem is being experienced not only here in Fort Scott, but nearly everywhere in states with hard water, the release said.

For any questions or a tour of the city's Water Treatment Plant, contact Michael Mix at 223-5160.