New and Alternative Strategies in Skin Irritation Testing

Development for new topical products involves a great deal of risk assessment and safety testing. Each ingredient must be carefully scrutinized to ensure that it is safe and has a low risk of causing irritation. Before the product can be marketed, it must undergo rigorous evaluations. Traditionally, this was done via animal testing. While this method is mostly effective, there are testing alternatives that are more affordable, more accurate, and reach across a broader spectrum of variables and associated factors.
Consumer needs demand expanded testing capabilities
A consumer’s satisfaction with a product extends beyond a visible skin reaction. If the product causes any type of unpleasant sensation, including burning, stinging, or itching, that can have a significant negative impact. Sensory irritation has long been studied by manufacturers of cosmetics and other products that require a topical application, yet to some degree it remains a mystery.
Neurophysiology has aided in increasing the ability to accurately gauge sensory irritation, there is still much work to be done. This is an area that is difficult to test, especially at lower levels, because the irritation is experienced in a sensory format and does not elicit a visible reaction. There can still be a reaction even if the appearance of the skin does not change.
Options for testing skin irritation: Human test methods
Testing that uses human subjects is not new, especially in skin compatibility tests. Ethical human testing that uses volunteers can provide invaluable insight and feedback on a product or substance. By using scarification tests, cumulative irritation patch tests, repeat open application tests, and extended duration patch tests, are commonly used in direct formulation or chemical application.
Extended duration product home use tests, exaggerated fabric rubbing tests, hand immersion tests, and forearm wash tests are often conducted in either a laboratory or even at home. These are extremely useful because the subject is able to provide more detailed feedback.
Options for testing skin irritation: In vitro systems
In vitro systems used as a device for testing or screening skin irritation is a fairly new technology. Developing human skin culture as a vehicle for predicting irritation has enormous possibilities that extend far beyond human testing or even animal testing in scope and cost. It has the capability to predict cumulative and acute skin irritation, including chronic irritation.
The Ocular Irritection® Assay System is used to test substances and materials for eye irritation while the Irritection® Assay System tests the skin’s reaction to potential irritants. These technologies, while fairly new, have proven to be both reliable and cost effective, surpassing other testing methods such as animal testing.
Skin irritation testing is much more than a manufacturer’s desire to create a product that consumers will love and, in turn, purchase. It extends far beyond marketplace races where companies are forever one-upping their competitors. In the end, it comes down to product safety – human safety. Testing is necessary, but accurate, affordable testing is absolutely vital.
It is time to look at what is effective, what is accurate, what works, instead of what is tradition. An in vitro system is the future of skin irritation testing. It is the new chapter in product testing, offering manufacturers a better way to give their customers safe products that they love.
In Vitro International is an industry leader in the development and application of skin irritation and toxicity non-animal testing. To learn more about our Ocular Irritection® and Irritection® Dermal as well as other non-animal testing technologies that are in development, contact us at 1-800-2-INVITRO or complete the convenient email form on our website and a representative will contact you.