Substitution of allergenic preservatives: methylisothiazolinone and methylchloroisothiazolinone

Number

050-EN

Section

General Section

Use

Sector

Manufacture of bulk, large scale chemicals (including petroleum products)
Manufacture of fine chemicals

Function

Biocide

Process

Other

Product category

Biocidal products

Application

used as a preservative in cosmetics

Abstract

A Ph.D. thesis showed that methylisothiazolinone could be remarkably reduced if it was combined with phenoxyethanol in conservation of cosmetic cream.

Substituted substances

Methylisothiazolinone

CAS No. 2682-20-4 EC No. 220-239-6 Index No.

Chemical group

Sulfur-nitrogen heterocycles

Classification: hazard statements

H330 Fatal if inhaled
H311 Toxic in contact with skin
H301 Toxic if swallowed
H314 Causes severe skin burns and eye damage
H318 Causes serious eye damage
H317 May cause an allergic skin reaction
H400 Very toxic to aquatic life
H410 Very toxic to aquatic life with long lasting effects

Alternative Substances

Phenoxyethanol

CAS No. 122-99-6 EC No. 204-589-7 Index No. 603-098-00-9

Chemical group

Glycol ethers

Classification: hazard statements

H302 Harmful if swallowed
H335 May cause respiratory irritation
H318 Causes serious eye damage

Reliability of information

Evidence of assessment: there is evidence of an official (positive) assessment of the substitution

Reason substitution

other reasons

Hazard Assessment

Both methylisothiazolinone (MI) and methylchloroisothiazolinone (MCI) are potent sensitisers. By substituting MI and MCI by a non-sensitising substance the allergy risk could be reduced. Substance to be substituted: Methylisothiazolinone may cause an allergic skin reaction, according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). It fulfils the criteria to be listed in the Substance Database according to SUBSPORTplus Screening Criteria (SDSC). » Check the Substance Database according to SUBSPORTplus Screening Criteria (SDSC) Alternative substance: The SCCS (Scientific Committee on Consumer Safety) considers 2-phenoxyethanol safe for use as a preservative with a maximum concentration of 1.0%, taking into account the information provided.

Description of Substitution

Methylisothiazolinone: Contact Allergy and Antimicrobial Efficacy is a Ph.D. thesis by Michael Dyrgaard Lundov from the National Allergy Research Centre in Copenhagen, Denmark. Both methylisothiazolinone (MI) and methylchloroisothiazolinone (MCI) are potent sensitisers that have been used as biocides for many years. Both the antimicrobial effect and the development of contact allergy are dose-dependent. A substitution of MI - partly or totally - would therefore represent an opportunity to decrease the risk of an allergic response. One of the conclusions of the research project was that MI could be markedly reduced if it was combined with phenoxyethanol. Phenoxyethanol (0,2%) in combination with MI (5 ppm) was sufficient to preserve e.g. cosmetic cream. "On the basis of previous safety evaluation 100 ppm MI is considered safe in cosmetics in the EU. But the prevalence of MI contact allergy is already higher than that of other allergenic preservatives. Combinations of allergenic and non-allergenic preservatives could reduce the use concentration of preservatives and thereby potentially reduce the number of contact allergy cases. The prevalence of MI allergy is high, and the concentration needed to elicit a reaction is lower than the concentration considered safe by the EU. A solution may be to reduce the permitted concentration of MI and only use it in combination with other non-allergenic preservatives. This may also serve as a model for a more general approach to reducing allergy problems caused by allergenic preservatives." Phenoxyethanol was not effective alone e.g. against Staphylococcus aureus.

Case/substitution evaluation

This case study shows the substitution of a dangerous substance with a less dangerous substance. Nevertheless, work should be carried out on a complete substitution of the risks. Both methylisothiazolinone (MI) and methylchloroisothiazolinone (MCI) are potent sensitisers. Phenoxyethanol is not categorised as a sensitising substance. It is a common preservative in cosmetics. More information on the subject can be found in the BAuA report „Survey on alternatives for in-can preservatives for varnishes,paints and adhesives“.

State of implementation

Pilot study

Date and place of implementation

Denmark

Type of information supplier

Research

Contact

National Allergy Research Center Department of Dermato-Allergology Gentofte Hospital, University of Copenhagen https://www.videncenterforallergi.dk/

Further information

Jakob Ferløv Schwensen Contact Allergy to Methylisothiazolinone – Observational and Experimental Studies Forsvaret 02.06. 2017 Dansk resumé   Download ph.d.  Michael Dyrgaard Lundov Methylisothiazolinone: Contact Allergy and Antimicrobial Efficacy Forsvaret 06.05. 2011 Dansk resumé  Download ph.d.

Type of publication and availability

freely available

Publication source: author, company, institute, year

Tomas Rydberg, "J. Cleaner Prod. 1994 Volume 2 Number 1" Abstract available from: http://www.sciencedirect.com/science/article/pii/0959652694900191

Publication source

Type of publication and availability

https://www.videncenterforallergi.dk/wp-content/uploads/files/ph.d-afhandlinger/phd-lundov.pdf

Date, reviewed

December 11, 2020