FAQs about Phosphorus and Automatic Dishwasher Detergent

Q: What is phosphorus?

A: It is a naturally occurring element in all forms of life; for example, it is part of the structural framework of molecules such as DNA. All humans and plants contain phosphorus. Phosphorus is the 11th most common mineral in the earth’s crust. It is an essential nutrient and is part of the natural cycle of life.

Q: Where would you find phosphorus?

A: It has many uses and applications other than just automatic dishwasher detergent, including vitamins, animal feeds, pharmaceuticals, glass, china, detergents and in the manufacturing of steel and plastics. Human and animal wastes are also sources of phosphorous.

Q: Why was phosphorus in household automatic dishwasher detergents? What is the benefit?

A: In automatic dishwasher detergent, phosphorus is a multi-functioning aid that breaks up food soils (dried or greasy food) and provides consumers with clean dishes. It also ensures that no calcium-lime film remains on your glasses or dishes and prevents obstruction of your dishwasher’s jets and pipes and excessive water usage. There is now a federal regulation under the Canadian Environmental Protection Act (CEPA) that only allows a trace amount in household automatic dishwasher detergent. Phosphorus is still used in institutional settings. Commercial dishwasher machines are designed for high volume throughput. Due to the unique chemistry of phosphorus, its elimination would increase the number of cleaning cycles required, thereby increasing water and energy usage to achieve the same level of cleanliness. This would add to the environmental load that all Canadians and businesses are trying to reduce.

Q: Is there an impact from phosphorus on our environment?

A: Phosphorus supports the growth of plants, including algae. When too much phosphorus is present, excessive amounts of algae can develop. This may lead to undesirable water quality impacts including reductions in aquatic life, poor taste and odors in drinking water.

Q: Will the phosphorus in dishwasher detergent reduce blue-green algae blooms in our waterways?

A: This issue is complicated and reductions of phosphorus in dishwasher detergent will not solve the problem since these products account for less than 1% of the total phorphorus in our waterways. The issue is:

  • Blue-green algae are, in fact, bacteria and not algae. The term is used to describe its appearance.
  • Blue-green algae are technically known as cyanobacteria and are a phylum (or “division”) of bacteria that obtains its energy through photosynthesis. Blue-green algae require several contributing factors in order to form: nutrients, shallow water, warm temperature, and areas of slow moving water.

Q: Can I still use my old dishwashing product?

A: Yes. Although regulations in Canada have changed and products on store shelves are phosphate free, you are able to exhaust your personal supply of dishwashing product.

Q: How can I prevent filming?

A: Read the dishwasher use and care manual, make certain no items block the dishwasher sprayer arm so that enough water reaches the dishes, and ensure the water temperature is at least 120 degrees. Using a rinse aid may help minimize spotting and filming on dishes. Refer to Automatic Dishwashing Problems, Causes and Solutions for additional information.

Q: How can I remove film that is already present?

A: For non-metal items, we recommend a vinegar wash. Put two cups of white vinegar in a bowl and place on the bottom rack of the dishwasher. Run the glasses/dishes through a cycle with no detergent. Re-wash with your detergent to remove residual vinegar. For metal items, we suggest cleaning by hand using a stainless steel cleaner or silver cream.

Q: Who should I talk to if I have a question about a dish care product?

A: If consumers have questions about a specific cleaning product, consumers should contact manufacturers directly using the toll-free number on the package or by visiting the manufacturer website. For general information about dish care, visit www.healthycleaning101.org.