Epidemic of allergy to preservative Methylisothiazolinone
A preservative used in disposable baby wipes and other products is causing an increasing number of cases of allergic contact dermatitis.
Methylisothiazolinone (MI) has been used in a range of cosmetic and personal products, including disposable wet wipes, shampoos, conditioners, body washes, moisturisers, sunscreens and deodorants, as well as in paints, cooling tower water and cutting oils since the early 2000s.
Drs Jennifer Cahill and Rosemary Nixon, dermatologists with the Skin Health Institute (formerly the Skin and Cancer Foundation Inc), have included MI in their baseline patch test series for allergies since 2011, after European reports of increasing numbers of cases of MI contact allergy.
“Our current rate of positive test reactions to MI to November 2013 is 11.3% (40 patients who had relevant reactions of a total 353), compared with a rate of 3.5% (15/428) in 2011 and 8.4% (38/454) in 2012”, Dr Cahill wrote.
“MI is now the most common cause of allergic contact dermatitis in our patient population.”
Preservatives like MI are needed in moist wipes and other water-based products to prevent bacterial contamination.
“Interestingly it is parents using baby wipes on their children who are presenting with hand dermatitis, although it is likely that allergic contact dermatitis involving the groin in children may not be diagnosed accurately”, Dr Cahill wrote.
“Medical practitioners and consumers should be aware of the potential for allergic contact dermatitis to develop to MI from wipes, in particular causing persistent hand dermatitis.”
People with unexplained rashes should check the label of ingredients and see if it contains MI, said co-author Associate Professor Rosemary Nixon. They should then try an alternative product which does not contain MI. If their rash persists, they should see their GP.
Common Questions about MI
WHAT ARE THE SYMPTOMS?
Allergic contact dermatitis (ACD) commonly presents as an itchy red rash on the skin.
IS ALLERGY TO MI CAUSING NAPPY RASH?
It is possibly contributing to nappy rash, but there are many factors which contribute to nappy rash e.g. contact with urine, faeces, sweating, thrush. However, it is the parents of the babies who are being referred by their dermatologists for specialised allergy testing (patch testing) to determine the cause of their hand dermatitis, not the babies.
WHAT PRODUCTS CURRENTLY CONTAIN MI?
MI is a preservative used in water-based products. While wet wipes are our most common source of MI, it is also found in other disposable wipes, such as those used for make-up removal, some deodorants, moisturising lotions, cosmetics, shampoos, conditioners, body washes, work skin cleansers and sunscreens.
DO ALL BABY WIPES CONTAIN MI?
Not all baby wipes use MI as the preservative. Manufacturers are now moving away from using MI, and so it will be less commonly used in the future.
SHOULD MI BE REMOVED FROM THESE PRODUCTS?
Yes. That has been our recommendation. There are alternative preservatives that may be safely used. In December 2013, the Scientific Committee for Consumer Safety of DG Sanco, European Commission, recommended that MI should not be used in leave-on cosmetic products and restricted to 15ppm in rinse-off products.
CAN PARENTS LOOK FOR ALTERNATIVES? ARE THERE MI FREE BABY WIPES?
Yes there are.
WHAT ARE THE KEY RECOMMENDATIONS FROM THE STUDY?
This is a report of our findings published in the medical journal, which is an observational study.
WHAT IS RECOMMENDED TO REPLACE MI?
There are a whole range of alternative preservatives that can replace MI, including parabens.
HAVE YOU RAISED THIS WITH THE AUTHORITIES?
Yes. We have spoken to the ACCC addressing it as a consumer safety matter. We have also alerted NICNAS (National Industrial Chemicals Notification and Assessment Scheme).
HAVE YOU BEEN IN TOUCH WITH THE MANUFACTURERS OR THE RETAILERS?
Yes, and many of them are taking steps to make the changes and remove MI from their products.
WHO HAS NOT?
That’s a question best addressed with the retailers or the ACCC. We are medical researchers and this question is really one for the regulators or the retailers.
WHAT IF I HAVE A PATIENT WHO IS ALLERGIC TO MI?strong>
Due to the increasing number of people developing an allergy to MI we have prepared an information sheet for those who have been diagnosed with an allergy to this preservative.
Download patient handout about MI here
Information for Maternal and Child Health Nurses
What is MI?
Methylisothiazolinone (MI) is a preservative used in baby wipes and other personal products, which is currently causing an appreciable number of cases of allergic contact dermatitis, an itchy skin rash. Preservatives like MI are needed in moist wipes to prevent bacterial contamination.
Where is MI found?
MI may be found in a range of cosmetic and personal products including:
- Disposable wet wipes including baby wipes and make-up removal wipes
- Shampoos and conditioners
- Body washes and hand cleaners
Who is affected?
Interestingly it is the parents and carers using baby wipes on their children who are developing hand dermatitis, caused by allergic contact dermatitis to MI. However it is likely that allergic contact dermatitis involving the nappy area in children and babies may not be diagnosed accurately, and considered just to be nappy rash.
Maternal and Child Health Nurses and medical practitioners, as well as parents of babies and young children, should be aware of the potential for allergic contact dermatitis to develop to MI from baby wipes.
What are the symptoms?
- An itchy red rash on the hands and fingers (similar appearance to eczema).
- Babies or young children may present with ‘nappy rash’ that is persistent and resistant to treatment (however there are many factors which contribute to nappy rash for example, contact with urine, faeces, sweating and thrush).
How is allergic contact dermatitis to MI diagnosed?
Patch testing, which involves testing on the back over several days (not prick testing) is used to diagnose allergy to MI.
How to prevent allergy to MI?
All users of baby wipes should check packaging to ensure that the product does not contain MI. NOT ALL WIPES CONTAIN MI. Other products used should also be checked for this preservative as well.
People with unexplained rashes should check the label of ingredients and see if it contains MI.
Alternative products should be used if necessary.
Where to get help?
If products containing MI are avoided and yet the rash persists, treatment should be sought from GPs and/or a dermatologist.
Advice from the Skin Health Institute can also be sought. Phone Amanda, 03 9623 9402 or email firstname.lastname@example.org
Download Information sheet for Maternal and Child Health Nurses here
Download Patient Handout MI allergen info sheet
Letter to the Editor “Methylisothiazolinone in baby wipes: a rising star among causes of contact dermatitis” is available in the Medical Journal of Australia 2014; 200 (4): 208.