Fall 2026

Risk Assessments of Wearable Electronic Devices

By Seth Larch

Over the past decade, there has been a substantial increase in the popularity and use of wearable electronic devices by consumers.  These devices include fitness trackers, virtual reality (VR) headsets, smart glasses and watches, skin monitors, and rings.  In 2025 alone, the major platforms sold roughly 14.5 million units of extended reality (XR) devices (Gallo, 2026).  Some wearable electronics are typically worn for short periods of time, while others are intended to be worn for most of the day.  Since these are skin-contacting devices, exposure to certain chemicals found in these products can present health concerns at sufficient exposure levels, either due to irritancy or, more significantly, from allergic sensitization.  Chemicals used in the production of these products – acrylates and glycidyl ethers in adhesives, formaldehyde, nickel, certain antimicrobials, isocyanates in uncured polyurethane foam, and various dyes – can potentially leach from the device through prolonged use, creating a potential biocompatibility concern for users.

Allergic contact dermatitis (also called skin sensitization) is an immune system response that can result from dermal exposure to natural and synthetic chemicals.  Once skin is sensitized to a chemical, even very small exposures can elicit a dermal reaction – a chronic susceptibility that may last for years if not a lifetime.”

Given the differing intended uses of wearable electronic devices, as well as the nature of the types of potential adverse health responses, it is important to conduct product-specific risk assessments to protect consumers from hazardous exposures.  Skin irritation can often be a quick response but may require a high exposure concentration to produce an effect.  Allergic contact dermatitis (also called skin sensitization) is an immune system response that can result from dermal exposure to natural and synthetic chemicals.  Once skin is sensitized to a chemical, even very small exposures can elicit a dermal reaction – a chronic susceptibility that may last for years or even a lifetime.

Various testing methods can be used to help understand what chemical exposures a consumer can potentially experience by using wearables.  Typically, testing involves extracting individual components or fully manufactured devices in a solvent considered relevant to human exposure (e.g., artificial sweat) in combination with an aggressive solvent (e.g., isopropyl alcohol).  By extracting a component or device in an aggressive solvent, the chemicals detected in analytical methods represent a worst-case scenario for consumer exposure.  However, in some cases, using an aggressive solvent can result in degradation of the tested component and may be unrealistic for the intended use of the device.  Thus, extraction in a solvent relevant to human exposure can provide a more realistic set of chemicals that would be potential biocompatibility concerns.

To conduct risk assessments of chemicals identified in extraction studies, scientists use a combination of human, animal, and in vitro studies to understand and assess the potential hazard and risk of a chemical.  For assessing skin biocompatibility, the ideal chemical dataset would include a combination of reliable skin sensitization studies (e.g., guinea pig maximization tests, mouse local lymph node assays, human patch tests) and skin irritation studies (e.g., acute dermal irritation/corrosion studies).  In some cases, in vitro, in silico, and in chemico data can be considered a reliable method for assessing irritation or sensitization; however, there are obstacles that can make risk assessment challenging.  For example, chemicals that may be detected in wearable electronic devices, particularly process chemical degradants, can lack the data necessary to assess skin biocompatibility.  One approach is to identify a surrogate or analog chemical with data that can be used to support the assessment.  In this case, an important factor of the surrogate chemical is whether it demonstrates the same reactivity in a quantitative structure-activity relationship (QSAR) program.

Another obstacle in a risk assessment is when a chemical has conflicting experimental data.”

Another obstacle in a risk assessment is when a chemical has conflicting experimental data.  Some chemicals, for example, may have multiple animal studies with different results.  If one study indicates a chemical is sensitizing while another indicates it is non-sensitizing, additional steps may be needed to better understand the data and determine which set of study findings would be more applicable to the specific wearable device.  Once the hazard of a chemical is identified, an acceptable exposure level can be derived and compared to the results of product testing.  Acceptable exposure levels are fairly conservative and include uncertainty factors intended to address the susceptibility of sensitive segments of the population.

As the increase in use of wearable electronic devices continues, it is important to address proactively any potential skin biocompatibility issues that may result from their use.  In particular, chemicals with known toxicological effects should be assessed accurately to ensure that skin effects are mitigated among users.