Laundry Products Research
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PART A - wash only
Wash & Rinse
PART B - total cycle
Greywater
Gardens
Washing machines
Legal matters
Hardness
Sodium adsorption ratio

In February 2008, Lanfax Laboratories, in collaboration with Choice, examined 21 liquid laundry detergents and compared them with four top -selling powder detergents. Choice published the results of the wash and rinse performance tests in Choice Magazine in June 2008 (also see www.choice.com.au).  We will publish more detailed graphs on this site at the end of July 2008.

WARNING:   The use of the term "Environmentally Friendly" should not be used for laundry detergents or other household cleaning agents, or soaps.  Every powder and liquid carries some environmental hazard.  What we need to be mindful of is which ones are "environmentally responsible" - that is, their choice provides the lowest environmental hazard to the receiving environment.  In some way we are all "responsible" for our environment, so "choose to use" those with the least hazard.

Please note:  Product formulations may have changed since these products were analysed. Manufacturers are under no obligation to disclose when formulations change.  Lanfax Labs has no means to maintain the analysis of product as at today's purchase.  Lanfax Labs can only report the samples tested at the dates disclosed in the information below.  

The information provided on these pages is the unique research of Lanfax Laboratories, investigating the potential impact of powder laundry detergents on our environment. This research is presented in two parts:

Part A:   At the beginning of 2007, Lanfax Labs and Choice (Australian Consumer Association) undertook collaborative research on 49 concentrated powder laundry detergents available in Australian and New Zealand.  These products were tested by Choice for various wash and rinse performance tests and are reported in their April edition of Choice (available from www.choice.com.au). The dosing rates used were for  "wash only" cycle of either a front loader or a top loader. These products were mixed with water (equivalent to rainwater) at the rate indicated by ACA from their calculations and provided to Lanfax Laboratories. The data reported are, therefore, representative of the "wash" cycle only for the respective type of machine - top loader or front loader.  Click on PART A to the left if you want to see the results of this research. 

The 2008 tests for 21 liquids and four powders will be added towards the end of July 2008

Part B:  54 powders and 41 liquid laundry detergents were mostly purchased by Lanfax Laboratories from supermarkets in Armidale, NSW (during late 2004, early 2005) while a few samples were supplied, without charge, by various manufacturers and suppliers. Samples of each of these products were mixed at two rates: one specifically for front loading washing machines; and one for top loading washing machines. The rates were calculated from weighed samples of a known volume from a freshly opened pack and mixed at the manufacturer's recommended dose for a normal wash. In the case of front loaders, a volume of 75 L was chosen as average total water use and 150 L for top loaders from previous research by Lanfax Laboratories. 

Except for the collaborative work in Part A, or a few boutique suppliers for Part B, all the research has been funded solely by Lanfax Laboratories.

Disclaimer: In no way does this research recommend or endorse ANY product, rather it ranks the products for each of the analyses performed. Conclusions may be drawn from the ranked data as explained with each graph, however, the potential impact of the laundry products on the environment depends on many complex inter-relationships such as:
            concentration at which the products are used in the wash cycle;
            the method of disposal of the wastewater;
            the receiving environment (land, river or ocean disposal);
            the soil loading rates and frequency of discharge; and
            the vegetation growing on the discharge area.

The Homeowner:  As homeowner, YOU alone have total responsibility for the choice of product, the concentration at which the product is used and the method of water disposal. While you may claim not to know what is in the product, perhaps you should not be using a product for which you don't know the consequences of your actions. Buying a product based solely on price is not a sound environmental action, nor is being blinded by clever advertising.  Buying a product because it is based upon "natural" ingredients may not be a better choice. There are many natural products that have severe consequences when irrigated onto your garden or lawn.

Choose from the following  table (double click on your choice)

Wash Effectiveness
None of these data refers to either the quality of the wash or the effectiveness of the rinse.  The assumption has been made that the manufacturers' recommendations are based upon an effective wash and rinse in normal washing machines, either front-loading or top-loading at the rates given for each machine type.  Some detergents are specified as suitable in either front-loading or top-loading, some products are unsuitable for front-loading while some products make no statement as to suitable type. However, with the different capacities of the washing machines (from 4 kg to 10 kg), it is often unclear as to how much detergent should be used.

Some of the components of the detergent's formulation are to neutralise the 'hardness' of water, that is, bind the calcium and magnesium ions so they remain in solution, rather than deposit a scum as happens when ordinary soap is used with 'hard' water. Therefore, when using rain water or 'soft' water, a smaller dose of detergent can be used.

Details of wash and rinse performance testing is carried out by Choice and further details can be obtained at www.choice.com.au

NOTE:  Lanfax Laboratories' research into household chemical effects on wastewater is on-going. A program is to examine dish-washing detergents (hand and machine) was carried out in 2007 for with a New Zealand Regional Council. The research included wool washes, fabric softeners, bleaches and nappy wash products. There is no intention to test personal care products such as body soaps, hair shampoos or hair conditioners at any time unless some benevolent funding is available.

SEPTIC TANK SAFE Unfortunately, there is usually no information on the packaging that assists the buyer in choosing a product suitable for disposal to the septic tank.  There are no standards for products to be disposed to septic tanks, and definitely no guidance on what can be safely disposed of to soil. The septic tank can usually sustain high loadings of salts, but the soil is the medium that is likely to be badly affected by salts, in particular sodium.

UNITS OF MEASURE
All units of measure are in metric terms:     1000 millilitres (mL)                    =    1 litre (L)
                                                                         1000 grams (g)                            =   1 kilogram (kg)
                                                                         1000 milligrams per litre (mg/L) =   1000 parts per million (ppm)

            When we measure concentration, we talk about milligrams per litre (mg/L) for liquids, or milligrams per kilogram (mg/kg) for solids.

Water Hardness
The hardness of water is an aesthetic quality that relates to how well soap lathers in water.  I have created another page on "HARDNESS" because it is a term we need to understand so that we can adjust the dose of laundry detergent, and other washing products, to match the 'hardness' of the water we use.  Detergent manufacturers make their products for a particular water quality and that information is not generally available to us, so we can only use the amount recommended on the packet as a guide, or use our experience.

Calcium and magnesium in water imparts a 'hardness' depending upon the concentration of one or both of these elements.  As rain falls on land and runs over the surface into storages, or percolates through the soil to groundwater, calcium and magnesium salts dissolve in the water from the natural soil or bedrock.  Some soils have abundant calcium and magnesium, other soils are so highly weathered that these salts have long since been leached from the soil.

When we use soap for washing either ourselves or clothes, hard water tends to form a scum because of the calcium and magnesium.  The ring around the bath or skin on a cup of tea is a result of products formed in hard water.  Rainwater is soft, and smaller quantities of laundry detergent are required for the 'normal' wash'.

pH
pH is a measure of whether the washing water is either acid (pH less than 7) or alkaline (pH more than 7). The pH range for most biological purposes is pH 5-9.  Detergents are rarely acid (pH <7) because of the potential for acids to react with metals and 'eat away' the metal parts of the washing machine and drainage system.  Detergents are mostly alkaline, liquids less alkaline than powders which are generally highly alkaline. At pH>10 skin will be affected and some clothes may start to age prematurely as the fabric dissolves in the alkaline liquid. Highly alkaline wastewater may have a detrimental effect upon plant available nutrients as well as inducing soil dispersion.

Total alkalinity
I have added another section with relevant graphs on total alkalinity, the buffering capacity of greywater (laundry water).  Refer to that section  (click here).

Salinity
Much has been written about salinity and its effects upon the environment. However, salinity is also an issue where laundry water is discharged over the soil in gardens, on lawns and in septic drainfields.  A salt is simply a compound that dissociates (breaks up) in water to form  positive ions (cations) and negative ions (anions).  The main difference between organic compounds and salts is that while both may dissolve easily in water, the organic compound remains as an organic  molecule, but the salt dissociates into cations (positively charged) and anions (negatively charged).  Since most of the laundry powder is made from various salts, we need to limit the amount of salt we discharge onto land or into fresh water.  Be aware, when we talk about salt we are not talking about common salt (sodium chloride) but all the salts made up from calcium, magnesium, potassium and many cations as well as the anions of sulphate, phosphate, nitrate, chloride, and carbonate.

Salinity is measured in water as electrical conductivity, that is the higher the salt content, the easier electricity flows through the solution. The units of measure of electrical conductivity are microSiemens per centimetre (uS/cm), milliSiemens per centimetre (mS/cm) or deciSiemens per metre (dS/m).    1000 uS/cm   =  1 mS/cm    =  1 dS/m.  Electrical conductivity measurements are converted to salinity measurements (milligrams per litre) by multiplying the EC reading in deciSiemens per metre by a conversion factor (usually 680 for water and wastewater - although this factor may vary).

The second method of determining salinity is to measure the total weight of detergent used in the wash. This value is often difficult to derive from the information on the packet, because the usual measures are given in volumetric terms  (one scoop, one cup) and not in terms of mass (weight).  The greater the amount of detergent used, the higher the overall salinity.  Therefore the very bulky detergents (usually the generic brands of normal powders) are likely to be the most saline by this measure.  However, all salinity is not bad - it depends upon the specific components present, their proportion and not the total mass. Some salts are soil ameliorants (such as lime, gypsum, dolomite), some salts are plant nutrients (urea, ammonium nitrate, muriate of potash, superphosphate), but sodium salts are mostly always detrimental.

Sodium (Na)
The sodium component of salinity is a much more important issue than just salinity per se, because sodium has a serious effect upon plant physiology and soil structural stability. Just as our diets should avoid high sodium levels (common salt is sodium chloride) because of its effect upon blood pressure, so we should consider the environment and the potential impact of sodium on it. Sodium salts are used in detergents (but not as sodium chloride) because they are relatively inexpensive and always highly soluble. Sodium sulphate is used as a "manufacturing agent" in some detergents, that is, it is used to assist the manufacturer and may not have any value as part of the washing cycle.  Sodium carbonate (washing soda) used alone elevates the pH of water to over pH 10. The units of measure for sodium are in milligrams of sodium per litre.

When a sodium salt is dissolved in water it ionises to sodium ions (Na⁺) and the other part as an anion (negative charge) so that the sodium then acts independently of the anion, although influenced by salinity and pH.  Take for example sodium tripolyphosphate which is extremely soluble.  When dissolved in water it ionises to sodium cations and phosphate anions in equal numbers. The sodium cations act independently of the phosphate anions.

Sodium salts can never be biodegradable because they are inorganic compounds. So the label about biodegradability does not apply to any of the sodium salts in the laundry detergent.

Other cations
Measurements were also made for potassium, magnesium, and calcium in the detergents. Other than eight liquid detergents having more than 1 mg/L potassium in the full wash (front loader and top loader) while two of those had magnesium at higher concentrations than sodium. The concentration of the other elements was less than 1 mg/L.

For the powders,

Phosphorus (P)
Phosphorus compounds are used in detergents as "builders", enhancing the detergency action of the more expensive detergents.  Complex inorganic phosphates are used to disperse clays and keep them in suspension so they can be washed out of the fabric and then rinsed out.  Phosphates also emulsify oily materials and allow their removal from fabrics. Phosphorus is an essential plant nutrient. The units of measure of phosphorus are in milligrams of phosphorus per litre.

The 7.8 g P/wash - green "P" label on packet - is a voluntary standard and has no scientific basis. It certainly does not mean that the detergent has low phosphorus since 7.8 g P/wash equates to 52 mg P/L in a full wash of a front loading washing machine (and 104 mg P/L in an average front loader).  The NSW Department of Environment and Climate Change (DECC) impose licence limits on sewage treatment plants of 1.0 mg/L and are working towards a 0.3 mg P/L in effluent discharges. So reducing Phosphorus in areas where municipal effluent is discharged to rivers and creek is a valuable objective.  Where the effluent is discharged to land for reuse projects (forestry, pasture production), the phosphorus simply substitutes for phosphorus fertiliser application.

For those who consider phosphorus in detergent "a bad thing", be aware that when phosphorus is replaced by some other active agent (and there must be another active agent or the quality of the detergent diminishes), the effect of this alternative chemical on the environment needs to be as well understood as the effects of phosphorus. In many cases there is no understanding of the impact of this alternative and its use should therefore be avoided.  Simply using the statement that "natural is better" may not be the case.

Phosphorus movement through a soil is dependent upon loading rate and soil type. Just because sodium tripolyphosphate is highly soluble does not mean that it will leach through the soil and contaminate groundwater, or runoff to pollute streams.  Sandy soils have almost no ability to bind phosphorus and on these soils the use of phosphorus needs to be limited to only what the plants can absorb. On most clay soils, the phosphorus sorption capacity (ability to lock up phosphorus and prevent its movement) is extremely high and where these soils are in our greywater reuse area, the loss of phosphorus can be negligible.  It is important that we understand the soils to which we will reuse our greywater.

_{Be aware, manufacturers may have changed formulations since these analyses were done.  If phosphorus levels have changed, it is likely to be reflected in labelling on the packet. Products labelled "NP" have no added phosphorus, and products labelled "P" meet the industry standard (less than 7.8 g/wash).}

Please note the spelling of the element phosphorus - anything else is wrong, but a recent search in the NSW law court decisions shows 196 cases in which it is not spelt that way......so much for dotting iiis and crossing tttts, but that does not make the spelling correct!

Boron (B)
Very few products had sufficient boron to cause problems to even sensitive plants. As a result the products with boron have not been listed as there are other components that have a greater environmental risk. Boron is also used as borax  (boric acid) as a disinfecting agent and for removing odours, and it is from this source that the greater environmental risk may occur.  In many soils the addition of borax is recommended and for many plants a trace of boron is essential as in mature leaf tissue at up to 20 parts per million.  Boron is essential to the development and growth of new cells, for proper pollination and fruit set and synthesis of proteins.  In legumes Boron is essential for nodulation (a symbiotic relationship between bacteria and the plant).  So small levels of boron where the greywater is applied to vegetation may be a good element.  Boron, however, in high doses can be poisonous to plants. Most Eastern Australia soils are deficient in boron.

Boron is also present in laundry detergents and whitening agents as sodium perborate which is often called "solid hydrogen peroxide" because it has an extra oxygen that when dissolved in water acts as hydrogen peroxide, a strong oxidising agent.  Hydrogen peroxide is used for bleaching hair, and for washing wounds. Some manufacturers have moved away from sodium perborate to sodium percarbonate which has the same action - producing hydrogen peroxide but without the boron. Hydrogen peroxide deactivates, leaving just water.

Other ingredients
There are many other compounds used in detergents to remove stains, sweat, grease and oil, food residues and soil.  Some additions include enzymes, optical brighteners and disinfecting agents.  The make-up of laundry detergents is beyond the scope of this research.

Cost per wash
It is possible to estimate the cost of each wash if you know how much one cup (or other measure) weighs. You can calculate how many washes per kilogram and knowing the price per kilogram, estimate the cost per wash. 

Unfortunately, this is not easy to achieve with most of these products because the measure you are given by the manufacturer is often in volumetric terms (one cup, one scoop of 60 mL, one scoop unspecified volume) and you do not know, and cannot work out the weight of the recommended dose.  Where else does one buy a product by weight and consume it by volume? Is this a marketing strategy to prevent one from doing this calculation while browsing supermarket aisles.  Very few manufacturers advertise the "number of washes per pack" on their packaging. Such a simple task!  When manufacturers do give the "number of washes in a packet", simply divide the price of the packet of detergent by the number of washes.

Powder example 1:  Brand "axaa" costs $5.60 for a  1 kg packet.  The "number of washes in packet" is recorded as "20".
The cost per wash is $5.60 divided by 20, which is 28 cents per wash.

Powder example 2:  Brand "dede: costs $3.50 per 1 kg packet.  There is no indication of how many washes per packet.  The recommended dose is one cup per normal wash in top loader.  Assume one cup (250 mL volume) weighs about 200 g (that's not correct but may be used for this approximation).   Divide 1000 grams  (1 kg packet) by 200 grams to get 5 washes.  Therefore this cheaper powder (cheaper per packet)  will cost about $0.70 per wash, more than twice the cost of the dearer packet in example 1.

Over a year, the difference between example 1 and example 2 amounts to $153   (assume family wash once per day)

For liquids, the calculation is easy: divide 1000 mL (1 litre) by the dose of liquid detergent per wash, giving you the number of washes per litre.

Liquid example:  Brand xyx is $3.20 per litre and the dose for a normal wash in a front loader is one capful (stated size of 60 mL)
Divide 1000 mL by 60 to get 16 and a bit, then divide the $3.20 by 16 to get 20cents, so each wash costs $0.20 approximately

Water consumption

Based on a previous review of washing machine data (see washing machine page), Graph 1  indicates the range of volumes of "total wash" water from front loader and top loaders, based upon the average family washing about 36 kg of laundry each week. 

Graph 1.    Water use for 36 kg washing per week from range of front loading and top loading washing machines (Patterson, 2004)

Effect of laundry detergents on soil
A simple demonstration of the effect of laundry detergents on soil is presented in the figure below.  Five common soils representing sands, loams and clays (not in that order) are treated with a typical wash water (full load).  An identical column of soil is set up and treated with rainwater.  The differences between treatments (wash water compared to rain water) and across the soils (difference between the soils) is clearly evident in the figure.  What happens is simple - the detergent causes the soil to disperse (separate into individual particles) which then block the soil pores.  Since the soil is a natural filter system, the pores become blocked and the filter no longer functions.  Water percolation slows considerably and the water no longer wets below the surface.

Note:  the different volumes collected between the left hand and the right hand tube in each soil; note all the difference between soils.  In most cases the right hand column (washing water) was slower to percolate than the clean water (left hand column).

Product labelling
Used throughout the presentations on this website, the name of the product is followed by a letter in brackets, which is used to convey the rate at which the detergent was mixed with water:     
(B) suitable both front loading and top loading machines, mixed at the top loading rate;
(T)  suitable for top loading machines, mixed at this rate;  and
(NS) not stated which type they suit, mixed at top loading rate.

Block letters are used for those products specifically formulated for front loading machines.

COPYRIGHT:  Any use of the data in these pages must be accurately referenced to Dr Robert A. Patterson, Lanfax Laboratories PO Box W90 Armidale NSW.  Sale of the data is strictly prohibited, and use in publications for sale must receive prior approval in writing.

None of this information may be sold or traded - it should always be available "at no cost" to the community. Cut and paste reproductions of any of this material is not permitted without written approval from the author.

Reference:  Patterson, R.A. (2004) Water Efficiency, Domestic Appliances and Hydraulic Design for On-site Systems in Proceedings of 1st International Conference on Onsite Wastewater Treatment and Recycling held at Fremantle11th - 13 February, 2004, convener  Murdoch University Perth.  (This paper is available in PDF format)