Ingredient · Updated
Methylchloroisothiazolinone
Found in 2 products
What is Methylchloroisothiazolinone?
Methylchloroisothiazolinone is a synthetic preservative often used in personal care products and household items. It is typically manufactured through a chemical process that results in a stable compound used to prevent microbial growth.
This ingredient is valued for its ability to extend the shelf life of products by inhibiting the growth of bacteria, mold, and yeast. However, its safety profile has been contested due to potential skin sensitivity and allergic reactions, especially in leave-on products like lotions and makeup.
On labels, it's important to note that this ingredient may be combined with Methylisothiazolinone, another preservative, and may increase the risk of irritation for sensitive individuals.
Commonly found in: shampoos, conditioners, soaps, lotions, cleaning agents
What to watch
- There is a documented risk of skin allergies and irritation from prolonged exposure.
- Contact dermatitis is a notable concern when used in leave-on products.
Benefits
- Effective at preserving product longevity by preventing microbial contamination.
The FDA allows its use in rinse-off products, but advises caution in leave-on cosmetics due to dermatitis concerns.
Research indicates effective antimicrobial properties, but raises concerns over allergenicity and skin sensitivity.
Methylchloroisothiazolinone is synthetically derived and not animal-based, making it suitable for vegan products.
Sources: Cosmetic Ingredient Review Assessment · Safety Evaluation and Risk Assessment of Preservatives
Scout's take
Methylchloroisothiazolinone is a preservative used to prevent microbial growth. It is a known allergen and can cause skin sensitization. Its use is restricted in many products due to these concerns.
The case against
It is a leading cause of contact dermatitis and can cause allergic reactions.
from the analysis of Method Daily Shower Spray Eucalyptus MintHigh potential for causing allergic reactions and skin sensitization.
from the analysis of Safely Multi-Surface Cleaning Wipes CalmThe case for
It provides effective preservation against microbial growth.
from the analysis of Method Daily Shower Spray Eucalyptus MintEffective in preventing microbial growth in products.
from the analysis of Safely Multi-Surface Cleaning Wipes CalmMore from Scout's analyses
Methylchloroisothiazolinone is a preservative known for its effectiveness against bacteria and fungi. However, it is a potent allergen and can cause skin sensitization.
from the analysis of Method Daily Shower Spray Eucalyptus MintAll 2 products with Methylchloroisothiazolinone
Where Methylchloroisothiazolinone shows up
- Surface Cleaners 2 products
Higher-scoring picks without Methylchloroisothiazolinone
Products from the same categories whose analyzed ingredient list does not include Methylchloroisothiazolinone, scoring 80 or above.
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