A Word on Caustic Cleaners
© Robert Anderson PhD
Originally published in Organic NZ, May/June 2007, Vol. 66 No. 3
Some years ago at the dentist I picked up a popular women’s magazine. My eyes settled on a ‘health tips’ column. I was stunned at what I found myself reading. One of the tips recommended was to make up a sodium hydroxide solution as a gargle for sore throats. I rang through to the editor to explain the dangers to which this article exposed its readers and the future damages to be incurred by the magazine.

Lye, or sodium hydroxide as it is commonly known, is one of the most corrosive and dangerous chemicals to which we can be exposed. Many of us know it as caustic soda and this is in fact a more fitting name, for its caustic nature is often underestimated. This chemical has been available cheaply for some time from super markets. As a drain cleaner, in the neat form at least, it has been in use for decades. But surprisingly, sodium hydroxide finds its way into many household cleaners. For example, oven cleaners may contain the chemical under pressure. Hence the reason for the admonition that the user wears gloves and avoids eye contact. Sensible advice! One of my technicians nearly lost her sight making up a solution of this chemical in the laboratory. She added the sodium hydroxide to a beaker of previously warmed water.

Unfortunately, caustic soda is highly exothermic when going into solution and gives out enormous heat. (Sulphuric acid does the same.) This is the one instance when we should add it cautiously to cooled water. The extra heat generated served to bring the mixture to boiling point and blow it all over her and the laboratory ceiling. After dowsing her with vinegar to neutralize the caustic soda, we found that it had thankfully missed her face. A neighbour did the same thing when attempting to clean a drain. In her case, she was scarred for life.

Fortunately, Australian housewives will be better informed about the dangers of handling caustic soda following an Australian Competition and Consumer Commission Federal Court action[i]in December 1996. The ACCC considered the failure to include a statement on the label that the product may be mixed only with cold water contravened Section 52 and 53(c) of the Trade Practices Act 1974. This was the first case of its kind in which the ACCC instituted proceedings against a manufacturer/supplier of caustic soda – Glendale Chemical Products Ltd - after a consumer complained that he suffered injuries and property damage as a result of using the product in his home. This is a case where the instructions on the product’s label were inadequate in that they failed to inform consumers of the safe method of using the product. As ACCC Chairman Dr Allan Fels said: “The existing labelling encouraged uses which appear to be particularly hazardous. Consumers have a right to safe goods and to be provided with the appropriate information about products for use in their homes.”

On checking the instructions on a typical New Zealand product, I found this warning present. However, like many labels, you require a magnifying glass to see it.

So why is this chemical so dangerous? Users who get caustic soda on their fingers will undoubtedly say, “It feels all soapy.” What they may not realise is that the soapy feeling is due to the chemical dissolving their flesh. Caustic soda dissolves protein, hence the 'soapy’ feeling. This has more immediate dangers for such areas as the eyes since the thickness of the cornea is very fine. It would require very little chemical in the eye to completely destroy the cornea.

There are from time to time instances used in films and plays where the true danger of this chemical are all too gruesomely illustrated. It is shown in a scene from the 1999 movie Fight Club, where the character Tyler Durden puts it on the protagonist's freshly kissed hand to create a lip-shaped scar, symbolizing their commitment to the plan that makes up the movie's plot. It was also used as an assault weapon in an episode of US crime drama, CSI New York, in which the victim has the chemical thrown over his face, causing a chemical burn and his eventual death.

Caustic soda has been the mainstay of extreme cleaners. However, the phosphate chemicals widely used in many laundry detergents also pose hazards, to the environment and human health. Many cities in the US now require laundry detergents to be ‘low-phosphate’ to reduce environmental pollution. What happens is that manufactures often replace phosphates with caustics. The misconception is that low phosphates detergents are safe. They may be safer for the environment, but they are 100 times more caustic than standard phosphate detergents for humans. Caustics such as Lye (sodium hydroxide) or Common Bleach (potassium hypochlorite) clean by a chemical reaction that burns or eats away other substances. Caustics also wear out your clothes faster and dull fabric colours.

A common replacement for phosphates, much used before the 1980s, was nitrilotriacetate (NTA). Although very effective, this compound is cancer-causing and binds with heavy metals in the environment, thus creating a toxic risk to numerous species. Most laundry detergents now contain a form of NTA, a carcinogenic substance. [ii]

A little revision

Over the months, NZ Organic have published many Label Watch articles together with other warnings for consumers. In line with this, I feel it worth revising some of the products and dangers that we face using these particularly caustic and toxic chemicals in and around our homes[iii]: We have to remember that Environmental Protection Agency (EPA) studies have shown that indoor air pollutants in American homes are 3 to 70 times higher than outdoors and it would be very similar for the average NZ home.

• Since 1950, at least 70,000 new chemical compounds have been invented and dispersed into our environment. Only a fraction of these have been tested for human toxicity. We are, by default, conducting a massive clinical toxicology trial, and our children and their children are the experimental animals.[iv]

• 150 chemicals found in the home are connected to allergies, birth defects, cancer and psychological disorders.[v] In 1901, cancer was rare: one out of 8000 people got cancer. The cancer rate today is variously quoted as one in 2 or 3.[vi]

• The top cancer-causing products in the average home include the following[vii]: Johnson & Johnson Baby Powder w/Talc, certain Tartar Control Toothpastes, VO5 Hair Conditioner, hair dyes, Ajax Cleanser and Lysol Disinfectant.

• Of the chemicals found in personal care products, [viii]884 are toxic, 146 cause tumours, 218 cause reproductive complications, 778 cause acute toxicity, and 376 cause skin and eye irritations.

• Out of 2435 US poisonings in a one-year period, over 40% were due to exposure to disinfectants and similar cleaning products in the home.[ix]

I recently attended the Aotearoa Breast Cancer Conference where the presenter commented, “We don’t really know what causes breast cancer.” I was flabbergasted. Just by reducing - not eliminating - environmental carcinogens alone, it is claimed that the US would save at least 50,000 lives taken by cancer annually.[x] I’m sure a similar ratio would hold for NZ with its heavy dependence on pesticides and chemicals.

Our body's storehouse

Over the years, more toxic chemicals have been introduced to our everyday environment and in greater amounts. Consequently, the level of toxins stored in adipose tissues (fat cells) in our bodies has risen. Bio-accumulation studies have shown that some toxins remain stored in our bodies for the duration of our life. Greater and greater amounts are being stored at younger ages. One study showed that in the fat of 100% of the people tested was 1,4-Dichlorobenzene, a chemical found in most household deodorizers and room fresheners. An interesting US statistic is that women working in the home have a 54% higher death rate from cancer than women who work outside of the home.[xi] What would this be for NZ women?

Many diseases that used to occur later in life are now appearing at younger ages. Diseases that used to be rare are more frequent. For example, there has been a 28% increase in childhood cancer since the addition of pesticides into household products. Since 1977, the rate of cancer among American children has been steadily rising at a rate of nearly 1% each year.[xii] It is almost impossible to obtain the statistics for NZ children, but I have a feeling that it would not be far behind. We generally use the same caustic and chemical toxins as those used in the US. There is also an increased risk for leukaemia in children where parents have used pesticides in the home or garden before the child's birth.[xiii]

Asthma was once a very rare disease. Now the condition is extremely common. The asthma rate has tripled in the last 20 years. Again the US statistics for this are interesting: 29% for men, 82% for women. The higher rate for women is believed to be due to women's longer exposure times to household chemicals.[xiv]

The developing cells in children's bodies are more susceptible to damage than adult cells that have completed development, especially for the central nervous system. During the development of a child, from conception through adolescence, there are particular windows of vulnerability to environmental hazards. Most disturbing is the fact that, until a child is approximately 13 months of age, they have virtually no ability to fight the biological and neurological effects of toxic chemicals.[xv] Today, children have chemical exposures from birth that their parents never had until they were adults. Because children are exposed to toxins at an earlier age than adults, they have more time to develop environmentally triggered diseases, with long latency periods, such as cancer.[xvi]

Understanding the label

Warning labels on containers often refer only to toxic hazards from ingestion. However, only 10% of health problems from chemicals are caused by ingestion; 90% are caused by the inhalation of vapours and absorption of particles. Government regulations require that only the most extremely toxic substances must contain a warning label. I firmly maintain that chemicals and cleaners bearing label instructions such as those following, should be removed from your house immediately.

Do not induce vomiting (Caustic soda)

Corrosive - rinse from skin immediately (Caustic chemicals)

Harmful or fatal if swallowed, Call physician immediately,Warning! (These may mean that as little as 1 teaspoon of product can harm or kill an adult.)

And ask yourself: Do you still want to use products in your home that contain these caustic and other dangerous chemicals?


Robert Anderson BSc (Hons), PhD - 4 February 1942 to 5 December 2008

Robert Anderson was a Trustee of Physicians and Scientists for Global Responsibility (formerly Physicians and Scientists for Responsible Genetics) www.psgr.org.nz. He authored The Final Pollution: Genetic Apocalypse, Exploding the Myth of Genetic Engineering and several other publications on environmental, scientific, health and social justice issues.

View his lectures on this site

Address enquiries for Robert Anderson's publications in print to naturesstar@xtra.co.nz.



[i] Caustic soda supplier provides undertakings to Federal Court
[ii] The Merck Index
[iii] This information came from a conference call with Kay Heizer, Director of "Healthy Choices" (a non-profit organization comprised of doctors, nurses, environmental scientists and educators committed to teaching the public about the hazards of chemicals in our home and how we can avoid or minimize the risks):
[iv] Herbert L. Needleman, M.D., Philip J. Landrigan, M.D., Raising Children Toxin Free
[v] Consumer Protection Agency (CPA)
[vi] . The American Cancer Society
[vii] The National Cancer Prevention Coalition
[viii] US House of Representatives Report, 1989
[ix] State of California Study
[x] Dr. Lee Davis, former advisor to the Secretary of Health
[xi] 17- year EPA study
[xii] National Cancer Institute
[xiii] Journal of the National Cancer Institute
[xiv] Center for Disease Control
[xv] Herbert L. Needleman, M.D., Philip J. Landrigan, M.D., Raising Children Toxic Free
[xvi] Environmental Policy and Children's Health, Future of Children, Summer/Fall 1995;5(2):34-52