Not long ago, I started receiving inquiries about products such as The Laundry Solution (Tradenet) and The Laundry CD (OneSource), which claim to get clothes clean in automatic washers without the use of laundry detergents. After handling many email and telephone requests about whether they work and what science lies behind them, I finally decided to put the information on a web page.
Both these products, and their imitators, are essentially sealed plastic containers filled with a (possibly) colored liquid. The liquid never comes in contact with the laundry. By dropping them into your washer instead of using laundry detergent, the manufacturers claim that they'll get your clothes clean.
Yes and no. They don't do a thing to get your clothes clean, but if you follow the directions (using an imaginary disc or ball), you might get the claimed results, depending on what kind of laundry detergent you're currently using, what kind of water you have, what kind of soil you're typically afflicted with, and so on. It's important to note that the manufacturers of these devices seem to provide much more accurate information than the distributors. The distributors tend to leave out the important bits, about which more below.
It has nothing to do with quantum mechanics, or activated water, or mysterious magnets, or anything else of that sort. The science behind these devices is psychology: they make you feel comfortable using less detergent, or none at all. The science behind the instructions for use, however, is given below -- and it's the instructions, not the devices, that "work".
Laundry detergents consist of a number of components, the largest of which is very much like soap. Soap molecules are long chains of atoms with a special attachment at one end. The long chain repels water -- it's very much like a fat -- and the special attachment likes water. A typical one looks a little like this:
In fact, if you read books about the pioneer days (or any preindustrial time), soap was made by boiling a mixture of tallow (beef fat) and lye. The lye molecules attach themselves to the ends of the fat molecules, and the result, when the mixture cooled, was soap. Most modern laundry detergents look basically the same, but use a more complicated arrangement of atoms in the water-attracting part of the molecule; the more complex water-attracting part makes the detergent better at dealing with hard water than ordinary soap.
The reason that molecules of this sort -- one end attracting water and the other end repelling it -- are used for cleaning is that oily things stick together when in water. (Look at the little blobs of oil in Italian salad dressing, for example.) So when you put greasy clothes in a soap solution, the oily ends of the soap molecules attract and hold the oil and grease in the clothes, and non-oily ends attract the water. This allows the oil to be pulled out and washed away.
But in today's world, unless you have a profession that puts you in contact with a lot of oily things, most of the soil in your clothes consists of particulates like dust and dirt, or water-soluble chemicals from sweat, and so on. In these circumstances, the soap doesn't do any good: the water, plus the mechanical action of the washer churning and rubbing the cloth, is what actually cleans the clothes. So you don't really need very much soap. In fact, for many loads, you need none at all.
But excess detergent isn't a good thing: it sticks around in your washer, it forms compounds with hard water that settle on your clothes, and so on. Modern detergents are much better about these things than ordinary soap, but depending on the formulation of your detergent and the characteristics of your water, there may still be some deposition of hard-water compounds on your laundry. That's why these devices "work" (when they do): they do absolutely nothing except make you feel comfortable with not using detergent. If you can convince yourself to use less detergent without a little plastic disc or ball, you get all the benefits and you don't have to pay for the device.
The information that the manufacturers provide is a lot more up-front about this than most salespeople. Their information states plainly that the products will not remove stains, and that if clothes are greasy, you should add a small amount of laundry detergent. (Oddly enough, one laundry-doodad manufacturer also sells a laundry detergent to use for these cases. There's nothing special about the detergent.) The manufacturers of laundry soap want you to use as much as possible, and besides, it's convenient just to throw in a cup every time without having to think "Is this a greasy load? Are there any stains?". But if you do think first -- as the doodad-makers tell you to -- you get clean clothes while using a lot less detergent. Cheaper for you, and (perhaps) better for the environment.
Incidentally, some of these companies tell you to use borax. That's fine, but so is your favorite laundry detergent. The companies make much of the fact that borax is "a natural mineral". But so are asbestos, arsenic and uranium: just the fact that something is "natural" doesn't make it safe or environmentally friendly. In fact, borax sometimes used as a pesticide against roaches; a small child can die from swallowing as little as 5 grams of it -- about a fifth of an ounce.
If your clothes are extremely dirty, you might also add some detergent even though there's no grease. The reason is that commercial laundry detergents also contain chemicals that keep dirt particles suspended in water. This keeps dirt from settling back on clothes, which is a problem if there's a lot of it. And of course, if there are stains, you'll need either laundry detergent or a specialized stain remover.
Other chemicals in commercial laundry detergents include perfumes and fluorescent dyes. The latter make clothes look "whiter" by fluorescing in daylight. (That's why your white clothes seem to glow when you go somewhere that "black light" -- ultraviolet -- is being used.) Again, there's no real need for either of these if the objective is just to have sanitary clothes.
How much better your results are when using less detergent depends on which detergent you're currently using and on what's in your water supply. You may get much better results; you may get slightly worse results. But whether or not you use a disc or ball makes no difference at all.
It pays to remember that there's no free lunch: when washing without detergent, you get better results with warm or hot water -- as these devices' manufacturer's instructions state. You're trading the cost and environmental impact of using extra energy against the cost and environmental impact of using extra chemicals. Which alternative is best overall depends on your water, sewer and energy services, as well as how clean your clothes have to be: there's no universal right answer.
Don't be fooled by the scientific-sounding gobbledygook about how the ball works: there are lots of different explanations, and all use long, technical-sounding words. The manufacturers are careful not to say anything untrue, but they don't say anything relevant, either. For example, last year, Tradenet was touting "infra-red waves that change the molecular structure of the water." True, the laundry ball does emit infrared radiation, which does change the molecular structure of the water to a very tiny extent. But so would any other object at room temperature, and the effect -- of very slightly reducing the clustering of water molecules -- has nothing to do with how clean your clothes get.
More recently, TradeNet has started discussing something called "IE water". A link on their home page to a technical paper has been withdrawn since I saw it, but whether the claims in the paper are true or false, they had nothing to do with cleaning clothes.
But on with the laundry issues.
The web site with the good laundry information is http://www.safenet.com/wash/use.html Many of the distributors' web sites omit this critical advice for getting good "results." Note that TradeNet's information seems to move around a lot; let me know if this link stops working.
You might also look at: http://moof.com/nirvana/experiments/laundry/ and http://www.clickitown.com/tradenet/ for some evaluations of the product.
In order to evaluate something like The Laundry Solution or The Laundry CD (or even low-detergent washing), you need to do an experiment with reasonable controls. Just washing and looking at the results won't tell you anything: the load you're looking at might have been unusually clean or unusually dirty, and your judgement might be biased one way or the other. You also need a control, to make sure you're doing a valid comparison. Don't just wash with the gadget; do a load in plain water as well.
Detergent manufacturers and consumer testing agencies spend enormous amounts of time and money setting up tests that eliminate as much bias as possible. They use precisely-soiled swatches of precisely-matched cloth, put the detergents into coded boxes so that the operator doesn't know which one s/he's using, monitor the temperature of the wash water, run each test multiple times to check for repeatability, and so on.
So unless you have lots of patience and access to laboratory equipment -- as well as a look-alike ball or disc that doesn't contain whatever the magic ingredient is -- you'll have to make do with a cruder test, and enlist the help of a neighbor. Better yet, enlist the help of the person who's trying to get you to buy the ball or disc.
What you'll do is have your neighbor wash eight pairs of loads of your laundry. S/he'll have to prepare the washer according to the manufacturer's instructions, which typically ask that you run one or two cycles with the washer empty except for a cup of vinegar. Make up two charts that look like this:
Test Load A Load B #1 #2 #3 #4 #5 #6 #7 #8
Give one to your neighbor, and keep one for yourself. Now, for each test (pair of loads), put the loads into separate bags, and mark them A and B, and give them to your neighbor. Then, after you leave but before washing your two loads, s/he should flip a coin. If the coin comes up heads, s/he washes load A with the laundry doodad, and if tails, s/he washes load B with the laundry doodad. The other load should be done with plain water. S/he should record which load was done which way on the chart, which s/he should not show you until after all eight tests are complete. Similarly, when you receive the two loads back -- still separated, of course -- you should inspect them and record which of the two loads you believe was done with plain water, and which was done with the laundry aid. And likewise, you should not show your chart to your neighbor until all eight tests are done.
You and your neighbor should try to eliminate as many variables as possible: Each load in a pair should be the same size, the wash water temperature should be the same, the same cycle should be used, and so on.
After the eighth test is complete, compare your chart with your neighbor's. Pure chance will mean that the charts will match in 3-5 tests, which in turn means that the laundry aid and plain water do equally well (or equally badly). But if all eight tests match, or if none do (either of which can happen by chance only 1 time in 256), then it's very likely that there is a real difference between plain water and the laundry aid.
This may seem like a lot of trouble to go though, but if you're really serious about knowing whether or not these products work it's important to do tests with real controls, and with enough trials to be statistically valid. If you discover that there's no difference, which will almost certainly be the case, you might try to get your neighbor to do another eight loads, and this time use either a full recommended amount of detergent or a quarter of the recommended amount, again choosing by a coin flip. (If you can get your neighbor to do another eight tests, s/he probably has too much time on his/her hands.)
Any high-school or college freshman chemistry text with a section on organic chemistry can give you more information on the chemistry of detergent. A book on why science experiments are designed the way they are is Martin Goldstein's The Experience of Science, Plenum Press, 1984.
If you're interested in learning more about the chemistry of many of the consumer products we use daily, look for a book called Chemistry In The Marketplace by Benjamin Selinger, published by Harcourt, Brace. The book requires a basic knowledge of chemistry to get the most out of it, but even without some chemistry background the book is good for letting you know why things like laundry detergents, foodstuffs, cosmetics and so on are formulated the way they are -- and why they should sometimes be formulated differently, but aren't. Note that the book is sometimes indexed, for some reason, as "Chemistry In The Market Place", though the actual title is as given above.