Preferred IUPAC name: 2-Methyl-1,2-thiazol-3(2H)-one.Other names: 2-Methylisothiazol-3(2H)-one; 2-Methyl-4-isothiazolin-3-one;CAS Number:2682-20-4; EC Number:220-239-6;Chemical formula: C4H5NOS; Molar mass: 115.1 g/mol

2-methyl-2H-isothiazol-3-one;EC / List no.: 220-239-6; CAS no.: 2682-20-4; Mol.formula: C4H5NOS

2-methyl-2H-isothiazol-3-one; 2-methyl-2H-isothiazol-3-one (MIT); ; 2-methyl-4-isothiazolin-3-one; 2-methylisothiazol-3(2H)-one;2-methylisothiazolin-3(2H)-one; Methylisothiazolinone

IUPAC names: MIT; 2-Methyl-1,2-thiazol-3(2H)-one; 2-methyl-1,2-thiazol-3-one; 2-methyl-1,2-thiazol-3-one hydrochloride; 2-methyl-2,3-dihydro-1,2-thiazol-3-one; 2-Methyl-2H-isothiazol-3-one;2-Methyl-3(2H)-isothiazolon; 2-methyl-4- isothiazolin-3-one; 2-Methylisothiazol-3(2H)-one; 2-Methylisothiazolin-3-one; 3(2H) -Isothiazolone, 2-methyl-;  Methylisothiazolinone;2-Methyl-4-isothiazolin-3-one

CAS NO. 2682-20-4

2-METHYL ISOTHIAZOLONE

EINECS NO.:220-239-6

FORMULA: C4H5NOS

MOL WT. 115.15

H.S. CODE: 2934.10.7000

 

SYNONYMS

2-Methyl-3(2H)-isothiazolone; 2-Methyl-4-isothiazolin-3-one;

2-Methyl-2,3-dihydroisothiazol-3-one; Skycide; 2-Metil-2H-isotiazol-3-ona (Spanish) 2-Méthyl-2H-isothiazole-3-one (French);  Methylisothiazolinone; 2-Methyl-4-isothiazolin-3-one; 2-Methyl-2H-isothiazol-3-one; Other RN: 125794-71-0, 184720-17-0, 26172-54-3 (hydrochloride)

Isothiazolines are used as preservatives in the paint industry, where they serve to protect the product from fungal and mould attacks. One of the more common products of this kind used to be Kathon®, a 1.5%-aqueous solution consisting of 1 part methylisothiazolinone (CAS No 2682-20-4), and 3 parts of chloromethylisothiazolinone (CAS No 26172-55-4). This mixture can also be identified with a specific CAS No, 55965-84-9. To avoid risk of allergy the much weaker 1,2-benzisothiazolinone (commonly called BIT) is used. This is above all used as a preservative in latex paints. These substances are used in paint, adhesives, jointing compounds, cutting fluids and detergents. Paint, adhesive and detergents are products sold for both professional and consumer use.

Methylisothiazolinone is a 1,2-thazole that is 4-isothiazolin-3-one bearing a methyl group on the nitrogen atom. It is a powerful biocide and preservative and is the minor active ingredient in the commercial product Kathon(TM). It has a role as an antifouling biocide, an antimicrobial agent and an antifungal agent.

Applications

Methylisothiazolinone and other isothiazolinone-derived biocides are used for controlling microbial growth in water-containing solutions.

Two of the most widely used isothiazolinone biocides are 5-chloro-2-methyl-4-isothiazolin-3-one (chloromethylisothiazolinone or CMIT) and 2-methyl-4-isothiazolin-3-one (methylisothiazolinone or MIT), which are the active ingredients in a 3:1 mixture (CMIT:MIT) sold commercially as Kathon. 

Kathon is supplied to manufacturers as a concentrated stock solution containing from 1.5-15% of CMIT/MIT. For applications the recommended use level is from 6 ppm to 75 ppm active isothiazolones. Biocidal applications range from industrial water storage tanks to cooling units, in processes as varied as mining, paper manufacturing, metalworking fluids and energy production.

Kathon also has been used to control slime in the manufacture of paper products that contact food. In addition, this product serves as an antimicrobial agent in latex adhesives and in paper coatings that also contact food.

Other isothiazolinones

One isothiazolinone, Sea-Nine 211 (4,5-dichloro-2-n-octyl-4-isothiazolino-3-one, DCOI), has quickly replaced tributyltin as the antifouling agent of choice in ship hull paint. A recent study reported the presence of DCOI in both port water and sediment samples in Osaka, Japan, especially in weakly circulating mooring areas.

Of environmental concern, DCOI levels predicted in marinas now are considered a threat to various marine invertebrate species.

Isothiazolinones also are extremely toxic to fish.

In industrial use, the greatest occupational inhalation exposure occurs during open pouring. Non-occupational exposure to isothiazolinones by the general population also occurs, albeit at much lower concentrations.

These compounds are present in a very large number of commonly used cosmetics.

Human health

MIT is allergenic and cytotoxic, and this has led to some concern over its use. A report released by the European Scientific Committee on Cosmetic Products and Non-food Products Intended for Consumers (SCCNFP) in 2003 also concluded that insufficient information was available to allow for an adequate risk assessment analysis of MIT.

Rising reports of consumer impact led to new research, including a report released in 2014 by the European Commission Scientific Committee on Consumer Safety which reported: "The dramatic rise in the rates of reported cases of contact allergy to MI, as detected by diagnostic patch tests, is unprecedented in Europe; there have been repeated warnings about the rise (Gonçalo M, Goossens A. 2013). The increase is primarily caused by increasing consumer exposure to MI from cosmetic products; exposures to MI in household products, paints and in the occupational setting also need to be considered. 

The delay in re-evaluation of the safety of MI in cosmetic products is of concern to the SCCS; it has adversely affected consumer safety."

"It is unknown what proportion of the general population is now sensitized to MI and has not been confirmed as sensitized." In 2014, the European Commission Scientific Committee on Consumer Safety further issued a voluntary ban on "the mixture of Methylchloroisothiazolinone (and) Methylisothiazolinone (MCI/MI) from leave-on products such as body creams. The measure is aimed at reducing the risk from and the incidence of skin allergies. The preservative can still be used in rinse-off products such as shampoos and shower gels at a maximum concentration of 0.0015 % of a mixture in the ratio 3:1 of MCI/MI. 

The measure will apply for products placed on the market after 16 July 2015." Shortly thereafter, Canada moved to adopt similar measures in its Cosmetic Ingredients Hotlist.[13] Additionally, new research into cross reactivity of MI-sensitized patients to variants benzisothiazolinone and octylisothiazolinone have found that reactions may occur if present in sufficient amounts.

Allergic contact dermatitis

Methylisothiazolinone is used commonly in products in conjunction with methylchloroisothiazolinone, a mixture sold under the registered trade name Kathon CG. A common indication of sensitivity to Kathon CG is allergic contact dermatitis. Sensitization to this family of preservatives was observed as early as the late 1980s. Due to increased use of isothiazolinone-based preservatives in recent years, an increase in reported incidences of contact allergy to this product has been reported. 

In 2013 the substance was declared the 2013 Contact Allergen of the Year by the American Contact Dermatitis Society. In 2016 the Dermatitis Academy launched a call to action for patients to report their isothiazolinone allergy to the FDA.

On December 13, 2013 the trade group, Cosmetics Europe,following discussions with the European Society of Contact Dermatitis (ESCD),[20] recommended to its members "that the use of Methylisothiazolinone (MIT) in leave-on skin products including cosmetic wet wipes is discontinued. This action is recommended in the interests of consumer safety in relation to adverse skin reactions. It is recommended that companies do not wait for regulatory intervention under the Cosmetics Regulation but implement this recommendation as soon as feasible."

On March 27, 2014, the European Commission’s Scientific Committee on Consumer Safety issued an opinion on the safety of Methylisothiazolinone. This report only considered the issue of contact sensitization. The committee concluded:

“Current clinical data indicate that 100 ppm MI in cosmetic products is not safe for the consumer.

"For leave-on cosmetic products (including ‘wet wipes’), no safe concentrations of MI for induction of contact allergy or elicitation have been adequately demonstrated.

"For rinse-off cosmetic products, a concentration of 15 ppm (0.0015%) MI is considered safe for the consumer from the view of induction of contact allergy. However, no information is available on elicitation.”[22]

Methylisothiazolinone, MIT, or MI, (sometimes erroneously called methylisothiazoline), is a powerful synthetic biocide and preservative within the group of isothiazolinones, which is used in numerous personal care products and a wide range of industrial applications.

It is a cytotoxin that may affect different types of cells. Its use for a wide range of personal products for humans, such as cosmetics, lotions, moisturizers, sanitary wipes, shampoos, and sunscreens, more than doubled during the first decade of the twenty-first century and has been reported as a contact sensitizing agent by the European Commission’s Scientific Committee on Consumer Safety.

Industrial applications also are quite wide ranging, from preservative and sanitizing uses to antimicrobial agents, energy production, metalworking fluids, mining, paint manufacturing, and paper manufacturing, many of which increase potential exposure to it by humans as well as organisms, both terrestrial and marine. Industrial applications in marine environments are proving to be toxic to marine life, for instance, when the effect of its now almost-universal use in boat hull paint was examined.[1]

Methylisothiazolinone is a 1,2-thazole that is 4-isothiazolin-3-one bearing a methyl group on the nitrogen atom. 

It is a powerful biocide and preservative and is the minor active ingredient in the commercial product Exocide. 

It has a role as an antifouling biocide, an antimicrobial agent and an antifungal agent.

Applications

Cleaners and polishes, such as all-purpose cleaners, cleaning and industrial use wipes, floor and furniture polishes/waxes, automotive washes, polishes and waxes

Laundry products, such as liquid laundry detergents, fabric softeners and pre-spotters

Liquid detergents, such as dish wash detergents and general liquid cleaning solution

Other applications, such as moist towelettes, air fresheners, moist sponges, gel air fresheners

Raw materials and surfactants preservation

Applications

Adhesive industry

Construction industry

Gypsum, plaster and mortar

Laundry and cleaning agents

Lubricant/coolants

Paint and coatings industry

Paper manufacture

Technical suspension/emulsion

Textile and leather industry

Water treatment

MIT

MIT can be used on its own to help preserve cosmetic products.

Following discussions with dermatologists, who reported an increase in cases of allergy to MIT in their clinics, the European cosmetics industry assessed the available information regarding the risk of allergic reactions to MIT, and in December 2013, the European Personal Care Association, Cosmetics Europe, issued a Recommendation for companies to discontinue the use of MIT in leave-on skincare products.

The European Commission’s independent expert scientific panel (the Scientific Committee on Consumer Safety, SCCS), which advises on safety matters, reviewed the use of MIT in cosmetic products.

In 2013, the SCCS also recommended that MIT be removed from leave-on cosmetic products and that the amount of MIT used in rinse-off cosmetic products should be reduced.

As a result, the European Commission changed the cosmetic law to ban the use of MIT in leave-on cosmetic products. Since 12 February 2017, it is no longer permitted to make these products available to consumers.

In addition, the maximum amount of MIT present in rinse-off products has been reduced and since 27 April 2018, all products made available to consumers must comply with the new limit.

If consumers have been diagnosed as allergic to MIT it is important to check the ingredient list of rinse-off cosmetic products. The name ‘methylisothiazolinone’ will always be listed as ‘methylisothiazolinone’ regardless of where in Europe a product is purchased.

MIT also has been used to control slime in the manufacture of paper products that contact food. In addition, this product serves as an antimicrobial agent in latex adhesives and in paper coatings that also contact food.

Human health

MIT is allergenic and cytotoxic, and this has led to some concern over its use. A report released by the European Scientific Committee on Cosmetic Products and Non-food Products Intended for Consumers (SCCNFP) in 2003 also concluded that insufficient information was available to allow for an adequate risk assessment analysis of MIT.

Rising reports of consumer impact led to new research, including a report released in 2014 by the European Commission Scientific Committee on Consumer Safety which reported: "The dramatic rise in the rates of reported cases of contact allergy to MI, as detected by diagnostic patch tests, is unprecedented in Europe; there have been repeated warnings about the rise (Gonçalo M, Goossens A. 2013). 

The increase is primarily caused by increasing consumer exposure to MI from cosmetic products; exposures to MI in household products, paints and in the occupational setting also need to be considered. The delay in re-evaluation of the safety of MI in cosmetic products is of concern to the SCCS; it has adversely affected consumer safety."

2-Methyl-4-isothiazolin-3-one

2682-20-4

Methylisothiazolinone

2-methylisothiazol-3(2h)-one

2-Methyl-4-isothiazoline-3-one

2-Methyl-3(2H)-isothiazolone

3(2H)-Isothiazolone, 2-methyl-

N-methylisothiazolone

Caswell No. 572A

N-Methyl-3-oxodihydroisothiazole

2-methyl-3-isothiazolone

C4H5NOS

2-methyl-1,2-thiazol-3(2H)-one

UNII-229D0E1QFA

2-METHYL-2H-ISOTHIAZOL-3-ONE

EINECS 220-239-6

229D0E1QFA

3(2H)-Isothiazolone, methyl-

CHEBI:53620

W-107150

2-Methyl-4-isothiazolin-3-one, 50% aqueous solution

Neolone

Microcare MT

Kordek MLX

MIT (biocide)

125794-71-0

Acticide M 10

Acticide M 20

Bestcide 600

Kordek 50

Kordek 50C

Neolone 950

methyl-isothiazolinone

Kordek 573F

Kathon CG 243

n-methylisothiazolin-3-one

N-METHYL-3-OXODIHYDRO ISOTHIAZOLE

2-methyl-1,2-thiazol-3-one

MIT 950

MT 10

2-Methyl-4-isothiazoline-3-ketone

2-methyl-4-isothiazolinone

2-methyl-3(2H)-isothiazoline

2-Methyl 4-Isothiazoline 3-one

2-Methyl-3(2H)-isothiazolone #

2-Methyl-4-isothiazolin-3-one (MI)

2-Methyl-4-isothiazolin-3-one, 95%

2-Methyl-4-isothiazolin-3-one, analytical standard

220-239-6 [EINECS]

2682-20-4 [RN]

2-Methyl-1,2-thiazol-3(2H)-on [German] [ACD/IUPAC Name]

2-Methyl-1,2-thiazol-3(2H)-one [ACD/IUPAC Name]

2-Méthyl-1,2-thiazol-3(2H)-one [French] [ACD/IUPAC Name]

2-methyl-4-isothiazolin-3-one

2-Methyl-4-isothiazoline-3-one

2-Methylisothiazol-3(2H)-one [ACD/IUPAC Name]

3(2H)-Isothiazolone, 2-methyl- [ACD/Index Name]

606203 [Beilstein]

methylisothiazolinone [Wiki]

MFCD01742315 [MDL number]

MI

MIT

N-Methylisothiazolone

T5SNVJ B1 [WLN]

2-Methyl 4-Isothiazoline 3-one

2-methyl-1,2-thiazol-3-one

2-methyl-2,3-dihydro-1,2-thiazol-3-one

2-Methyl-2H-isothiazol-3-one

2-methyl-3-isothiazolidinone

2-methyl-3-isothiazolone

2-Methyl-4-isothiazolin-3-one (MI)

2-methyl-4-isothiazolin-3-one(mit)

2-Methyl-4-isothiazoline-3-one, 50% aqueous solution

2-methylisothiazol-3-one

3(2H)-ISOTHIAZOLONE, METHYL-

50% aqueous solution

Methylisothiazolinone|2-methyl-3(2H)-isothiazolone

NCGC00164391-01

N-Methyl-3-oxodihydroisothiazole

N-Methyl-3-oxodihydroisothiazole, 95%

甲基异噻唑啉酮 [Chinese]

Translated names

2-Methyl-(2H)-isothiazol-3-on (de)

2-methyl-2H-isothiazol-3-on (MIT) (da)

2-Methyl-2H-isothiazol-3-on (MIT) (de)

2-methyl-2H-isothiazol-3-one (MIT) (mt)

2-methyl-2H-isothiazol-3-one (MIT) (no)

2-Methyl-2H-isothiazool-3-on (MIT) (nl)

2-methylisothiazol-3(2H)-on (cs)

2-methylisothiazol-3(2H)-on (da)

2-methylisothiazool-3(2H)-on (nl)

2-methyltetrahydroisothiazol-3(2H)-on (MIT) (cs)

2-Metil-2H-isotiazol-3-ona (MIT) (es)

2-Metil-2H-isotiazol-3-ona (MIT) (pt)

2-metil-2H-isotiazol-3-one (MIT) (it)

2-metil-2H-isotiazol-3-onă (MIT) (ro)

2-metil-2H-izotiazol-3-on (MIT) (hr)

2-metil-2H-izotiazol-3-on (MIT) (hu)

2-metil-2H-izotiazol-3-on (MIT) (sl)

2-metil-2H-izotiazol-3-onas (MIT) (lt)

2-Metil-2H-izotiazol-3-ons (MIT) (lv)

2-metilisotiazol-3(2H)-on (hu)

2-metilisotiazol-3(2H)-on (mt)

2-Metilisotiazol-3(2H)-ona (es)

2-metilisotiazol-3(2H)-ona (pt)

2-metilisotiazol-3(2H)-one (it)

2-metilizotiazol-3(2H)-on (hr)

2-metilizotiazol-3(2H)-on (sl)

2-metilizotiazol-3(2H)-onas (lt)

2-metilizotiazol-3(2H)-ons (lv)

2-metilizotiazol-3(2H)-onă (ro)

2-metyl-(2H)-izotiazol-3-ón (sk)

2-metyl-2H-isotiazol-3-on (MIT) (sv)

2-metyl-2H-izotiazol-3-ón (MIT) (sk)

2-metylisotiazol-3(2H)-on (sv)

2-metylo-2H-izotiazol-3-on (MIT) (pl)

2-metyloizotiazol-3(2H)-on (pl)

2-metyyli-2H-isotiatsol-3-oni (MIT) (fi)

2-metyyli-isotiatsol-3(2H)-oni (fi)

2-metüül-2H-isotiasool-3-oon (MIT) (et)

2-metüülisotiasool-3(2H)-oon (et)

2-méthyl-2H-isothiazole-3-one (MIT) (fr)

2-méthylisothiazol-3(2H)-one (fr)

2-Μεθυλ-2H-ισοδιαζολ-3-όνη (MIT) (el)

2-μεθυλισοθειαζολ-3(2H)-όνη (el)

2-метил-2H-изотиазол-3-он (MIT) (bg)

2-метилизотиазол-3(2H)-он (bg)

2-Methyl-4-isothiazolin-3-one

2682-20-4

Methylisothiazolinone

2-methylisothiazol-3(2h)-one

2-Methyl-4-isothiazoline-3-one

2-Methyl-3(2H)-isothiazolone

3(2H)-Isothiazolone, 2-methyl-

N-methylisothiazolone

Caswell No. 572A

N-Methyl-3-oxodihydroisothiazole

2-methyl-3-isothiazolone

C4H5NOS

2-methyl-1,2-thiazol-3(2H)-one

UNII-229D0E1QFA

2-METHYL-2H-ISOTHIAZOL-3-ONE

EINECS 220-239-6

229D0E1QFA

3(2H)-Isothiazolone, methyl-

CHEBI:53620

W-107150

2-Methyl-4-isothiazolin-3-one, 50% aqueous solution

Neolone

Microcare MT

Kordek MLX

MIT (biocide)

125794-71-0

Acticide M 10

Acticide M 20

Bestcide 600

Kordek 50

Kordek 50C

Neolone 950

methyl-isothiazolinone

Kordek 573F

Kathon CG 243

n-methylisothiazolin-3-one

N-METHYL-3-OXODIHYDRO ISOTHIAZOLE

2-methyl-1,2-thiazol-3-one

MIT 950

MT 10

2-Methyl-4-isothiazoline-3-ketone

2-methyl-4-isothiazolinone

2-methyl-3(2H)-isothiazoline

2-Methyl 4-Isothiazoline 3-one

2-Methyl-3(2H)-isothiazolone #

2-Methyl-4-isothiazolin-3-one (MI)

The list of isothiazolinones include  

Material

CAS #

EINECS #

(4-Chlorobenzyl)-3(2H)-isothiazolone 26530-09-6

1,2-Benzisothiazolin-3-one 2634-33-5

220-120-9

2-Butyl-1,2-benzisothiazolin-3-one 4299-07-4

2-Methyl-4,5-trimethylene-4-isothiazolin-3-one 82633-79-2

2-Methyl-4-isothiazolin-3-one 2682-20-4

220-239-6

2-Methyl-3-isothiazolone hydrochloride

26172-54-3

247-499-3

2-Octyl-3(2H)-isothiazolone 26530-20-1

247-761-7

4,5-Dichloro-2-cyclohexyl-4-isothiazolin-3-one 57063-29-3

4,5-Dichloro-2-octyl-3(2H)-isothiazolone 64359-81-5

264-843-8

4-Chloro-2-octyl-3(2H)-isothiazolone 64359-80-4 264-842-2

5-Chloro-2-(4-chlorophenylmethyl)-3(2H)-isothiazolone 66159-95-3

5-Chloro-2-methyl-4-isothiazolin-3-one 26172-55-4

247-500-7

5-Chloro-2-methyl-3(2H)-isothiazolone, calcium chloride complex 57373-19-0

5-Chloro-2-methyl-2H-isothiazol-3-one hydrochloride

26530-03-0

247-760-1

2-Methyl-4-isothiazolin-3-one calcium chloride 57373-20-3

Mixtures of these materials