From this experiment, it was found that each of the different brands of detergents have different pH and concentration values. I also discovered the amount of detergent left over on the clothes for various cycles. The different brands inevitably have different concentration and pH values because the amount of each component is different. Of the three granular detergents that I used, Tide was the most expensive, followed by Sunlight, and Xtra was the cheapest. It is evident that Tide was the most health-considerate brand. Its pH was 9.7 using the North American machine. Surprisingly, the pH of Xtra was lower than that of Sunlight with 9.9 and 10.2 respectively. Furthermore, one may find that the detergents don't dissolve 100% on water surprising. Although the main components of the detergents are indeed water-soluable, the "filler" components may not dissolve in water as well as the main components. The "filler" components are diverse molecules that does aid in the cleaning of clothing but is made of cheaper and more economic material (figure 1). Thus, the result is that these components do not dissolve during the short rinse period, especially in cold water. The companies use these to maximize their profits in taking up space in their container. It can therefore be inferred that the more expensive brands have less of the "filler" material

The average pH of human skin is between 5.5-6.5. All of the values measured above are significantly greater than the pH of the human skin. Using the recommended amount of detergent for the different companies, a pH of 9.5 is the average for North American washing machines. Since our clothes are on us almost every minute of the day, the surface in which our skin is in contact with for the majority of the day has a pH of 9.5. The effect of the detergents on our clothes can be as small as dry skin to clinically dry skin all over the body. This also inhibits the production of vitamin C in our skin. Vitamin C inhibits the formation of concentrations of melanin, the cause of some dark spots on the skin. Vitamin C also assists the skin in the production of collagen, which helps our skin maintain its firmness. While some remain that the amount of detergent left on clothing will not cause ANY harm to the human body, it is difficult to comprehend how it will remain the same when the clothes is 1000x more basic than the skin (Figure 2).

A study done to understand the harmful effects of detergents on health and environment, showed that 77.6% of respondents had experienced some kinds of skin irritation due to detergents. Studies later revealed that the detergent residues enter our bodies either through the skin or through the lungs. They cause many common health problems including allergies, skin infections and in rare cases, cancer. The artificial fragrances used in laundry detergents can prove to be allergic and to be highly irritating to lungs, causing serious health effects to people with asthma or chronic heart problems. The usual result of a continuous and excessive exposure of the skin to detergents is drying, fissuring and dotting of the keratin layer leading to increased permeability that causes sensitization, which may develop into dermatitis.

The solution to the grand problem is not nearly as complex as the problem: use less detergents. In my experiment, it showed that when one uses half the recommended amount of detergent, Tide had 100x less detergent left on the clothing, and both Sunlight and Xtra had 10x less detergent left on clothing. Another solution is to rinse more times. By using the European method (2-3 rinses), it showed that all of the brands had around 100x less detergent left over on the clothes.

Figure 1: The Precipitated "filler" material Figure 2: Tide after 1 rinse