Methyldibromo glutaronitrile

Methyldibromo glutaronitrile (MG) is a preservative used to limit the growth of bacteria and other micro-organisms in products such as cleaning agents, fabric conditioners, adhesives, paint and industrial oils.

What are the symptoms?

The main allergic reaction to MG is eczema, where the skin becomes red and swollen, sometimes with blisters that develop into small sores. The symptoms usually appear on the hands or face, i.e., areas that have been in contact with products containing MG.

How frequent is it?

In Europe

MG has been used as a preservative in cosmetic products since the early 1980s, and it seems that allergic reactions to MG are increasing. Analyses from 16 dermatology clinics in 11 countries including more than 50,000 patients showed an increase in MG allergy from 0.7% in 1991 to 3.5% in 2000 (see the graph). This trend is still continuing in Europe (figures not published).

MG allergy is decreasing in Denmark

Information on allergies from the Danish national allergy network shows that the prevalence of MG allergy among tested eczema patients was 4.5% in 2003, 3.9% in 2004, 3.5% in 2005, 2.5% in 2006 and 2.6% in 2007.This points to a decrease in the occurrence of allergic reactions to MG in Denmark. MG received much media attention in Denmark and it is likely that this led to the preservative being voluntarily omitted from many products. Additionally, in 2003, moves were made to ban the use of MG in stay-on products, such as creams. This ban took effect from September 2005 and has been extended to cover all cosmetic products (see below). Methyldibromo glutaronitrile is still one of the most frequent causes of allergy and cases of MG allergy are increasing in other European countries.

Where is it found/What causes MG allergy?

Earlier

Studies from Sweden and Denmark in the 1990s showed that between 4–6% of moisturizing creams on the market contained MG as a preservative. The largest amounts of MG were found in creams/lotions and liquid soap. Earlier, the vast majority of allergic reactions to MG came from cosmetics, especially creams/lotions and liquid soap used domestically or in workplaces.

Ban on use of methyldibromo glutaronitrile in cosmetics

In April 2003, the EU Commission legislated against the use of MG in cosmetic products designed to be in prolonged contact with the skin (stay-on products), for example, creams and lotions. This was on the background of the increasing occurrence of MG allergy in Europe. The ban was based on a study carried out by the EU Commission’s expert committee (SCCNFP).

Further research from the National Allergy Research Centre, among other places, has shown that other types of cosmetics, for example, liquid soap, are also frequent causes of MG allergy (see below).p>

As a result of these findings and those of the EU Commission’s expert committee from 2005, MG was banned in all cosmetics, including soaps and shampoo. This ban took effect from 22 June 2008. Consequently, from 22 June 2008 it has been banned to sell cosmetic products within the EU that contain MG. These products cover, for example, make-up, moisturizing creams, cleansing creams, sun protection creams and personal-hygiene products.

The recommendations of the Committee can be seen on the Commission’s homepage. 
 

Where is MG found now?

Cosmetics sold in the EU should no longer contain MG (as from 22 June 2008). However, it is advisable to check, both at home and at work, whether any cosmetic products, such as moisturizing cream and soap, bought before 22 June 2008 contain MG. If products contain MG, dispose of them. If a cosmetic product produced in the EU contains MG, the preservative should be named in the list of ingredients. MG should appear written as methyldibromo glutaronitrile (see the example below). It may not be spelt differently or appear under a different name.

MG is not banned in cosmetics produced outside the EU. Therefore, cosmetics bought outside the EU or over the Internet may contain MG.

MG is also found in other types of products, for example, cleaning agents, detergents and fabric conditioners, adhesives, paint, industrial oils, lubricants, and electrode paste. How often MG is used in these products is unknown, but it is thought to be seldom. When MG is used in detergents and cleaning agents, it must appear on the list of ingredients as methyldibromo glutaronitrile. However, for other products there is no certainty that any content of MG will be declared on the list of ingredients, and if it is declared, it is uncertain under which name it will appear. Methyldibromo glutaronitrile may also appear under its chemical name of 1,2-dibromo-2,4-dicyanobutane or its commercial names of Euxyl K 400 and Tektamer 38.

If you are allergic to MG and are in doubt about whether it has been added to any of the products you use, ask your dermatologist. If necessary, your dermatologist can contact the producer to find out what the product contains.

Diagnosis and treatment

MG allergy is diagnosed in the same way as for other forms of contact allergy using a patch test, also called a plaster test, on the back. The treatment is the same as for all forms of eczema.

Find out more about the treatment.

Research from the National Allergy Research Centre

In 2003, the prevalence of MG allergy was high among Danish eczema patients, just as in the rest of the EU countries. More precisely, 4.5% of eczema patients in Denmark were diagnosed with MG allergy in 2003. For this reason, MG became the subject of research at the Knowledge Centre for Allergies and this led to an intervention being launched.

An analysis of allergy data revealed a link between MG allergy and hand eczema and that MG allergy occurred in men and women equally often.

The main cause of the allergy came from cosmetic products preserved with MG in the permitted amounts. The cosmetics covered both stay-on products, such as moisturizing creams, and wash-off products, such as liquid soap.

The research showed that the eczema became less bothersome or disappeared in the majority of patients within six months of stopping using the product containing MG. These data appear in two publications.:

Artikel: Zachariae C, Rastogi S, Devantier C, Menne T, Johansen JD. Methyldibromo glutaronitrile: clinical experience and exposure-based risk assessment. Contact Dermatitis 2003;48(3):150-154.

Artikel: Johansen JD, Veien NK, Laurberg G, Kaaber K, Thormann J, Lauritzen M, Avnstorp C; Danish Contact Dermatitis Group. Contact allergy to methyldibromo glutaronitrile -- data from a 'front line' network. Contact Dermatitis. 2005 Mar;52(3):138-41.

In an experimental study it was shown that even small amounts of MG in a moisturizing cream (0.005%) used twice daily could provoke allergic eczema in most patients with MG allergy (see figure). The conclusion was that MG could not be safely used, even in small amounts, in stay-on products, such as creams and lotions.

Artikel: Pedersen LK, Agner T, Held E, Johansen JD. Methyldibromo glutaronitrile in leave-on products – elicits in low concentrations. Br J Derm 2004 151(4): 817-822.

Allergic reaction on the neck after 3 days’ use of a moi-

sturizing cream with a low concentration of MG (0.005%)

Experiments done in a PhD study carried out at the dermatology department at Odense University Hospital showed that repeated use and exposure to wash-off products preserved with permitted amounts of MG cause allergic eczema.

Allergic eczema from using liquid soap

preserved with MG (the person’s right arm)

Another study showed that MG accumulates on/in the skin. Consequently, many exposures throughout a day to small amounts of MG, for example frequent hand washing with a soap containing MG, was the equivalent to exposure to a large MG dose.

Artikel: Johansen JD, Veien NK, Laurberg G, Kaaber K, Thormann J, Lauritzen M, Avnstorp C; Danish Contact Dermatitis Group. Contact allergy to methyldibromo glutaronitrile -- data from a 'front line' network. Contact Dermatitis. 2005 Mar;52(3):138-41.

Furthermore, MG was added to a soap used by a person allergic to MG. When that person used the soap an allergic reaction appeared that was 6 times stronger than if the person had been exposed to MG alone.

 

Artikel: Pedersen LK, Haslund P, Johansen JD, Held E, Vølund A, Agner T. Influence of a detergent on skin response to methyldibromo glutaronitrile in sensitized individuals. Contact Dermatitis 2004:50:1-5

The information from these studies was sent to the EU Commission to support the need for further restrictions on the use of MG. This led to a ban being imposed on MG in wash-off products, such as soap and shampoo, and the ban remaining on MG in stay-on cosmetics, such as moisturizers.

The frequency of MG allergy is falling in Denmark

There has already been a significant fall in the occurrence of MG allergy in eczema patients and in 2007 the prevalence was 2.6%.

This can be attributed both to the legislation and to the intense focus the problem received soon after it arose in Denmark, leading to voluntary reduction in use of MG before it became mandatory.

What can you do yourself? Methyldibromo glutaronitrile (MG) has been banned since 22 June 2008 in all forms of cosmetics produced in the EU. If you have any products purchased before this date, both at home and at work, you should dispose of them.   Please note that cosmetics purchased outside the EU or over the Internet may contain MG.   The use of MG is permitted in other products, for example, detergents and cleaning agents, adhesives, paint and industrial oils. People who have been diagnosed with MG allergy should avoid exposure to any product containing MG. It is mandatory to include any MG content in the list of ingredients on cosmetics, detergents and cleaning agents. This is not the case for other products. As MG also appears under other names, it may be necessary to contact the manufacturer of the product to get a comprehensive list of ingredients.

Scientific publications  

Rastogi SC. Analytical control of preservative labelling on skin creams. Contact Dermatitis 2000:43:399-343.

Wilkinson JD et al. Monotoring levels of preservative sensitivity in Europe. A 10-year overview (1991-2000). Contact Dermatitis 2002:46:207-210

Zachariae C et al. Methyldibromo glutaronitrile: clinical experience and exposure-based risk as-sessment. Contact Dermatitis 2003:48:150-154

Jensen CD el al. Methyldibromo glutaronitril in rinse-off products causes allergic contact dermatitis – an experimentel study. Br. J. Dermatol 2004:150:90-95

Pedersen LK, Haslund P, Johansen JD, Held E, Vølund A, Agner T. Influence of a detergent on skin response to methyldibromo glutaronitrile in sensitized individuals. Contact Dermatitis 2004:50:1-5

Rastogi SC, Zachariae C, Johansen JD, Devantier C, Menné T. Determination of methyl dibromo glutaronitrile in cosmetic products by HPLC with electrochemical detection – method validation. J. Chromatogr A. 2004:1031:315-7.

Pedersen LK, Agner T, Held E, Johansen JD. Methyldibromo glutaronitrile in leave-on products – elicits in low concentrations. Br J Derm 2004  151(4): 817-822

Johansen JD, Veien NK, Laurberg G, Kaaber K, Thormann J, Lauritzen M, Avnstorp C. Danish Contact Dermatitis Group. Contact allergy to methyldibromo glutaronitrile -- data from a 'front line' network. Contact Dermatitis. 2005 Mar;52(3):138-41.

Jensen CD, Johansen JD, Menné T, Andersen KE. MDBGN contact allergy: effect of single versus repeated daily exposure. Contact Dermatitis 2005; 52: 88-92

Johansen JD, Veien NK, Laurberg G, Avnstorp C, Kaaber K, Andersen KE, Paulsen E, Sommerlund M, Thormann J, Nielsen NH, Vissing S, Kristensen O, Kristensen B, Agner T, Menné T. Decreasing trends in methyldibromo glutaronitrile contact allergy – following regulatory intervention - Antaget til publikation 2008