Development of a route of exposure model using silicone wristbands as personal samplers

Myexposome Inc. received a $449,958 Project Grant from the National Institutes of Health National Institute of Environmental Health Sciences to develop a route of exposure model using silicone wristbands as personal samplers. The grant is part of the Environmental Health program (CFDA 93.113), which aims to foster understanding of human health effects from environmental exposures.

Under the award, Myexposome will utilize multiple silicone wristband configurations in a field demonstration among up to 30 individuals to study atmospheric and contact absorption of over 1,500 chemicals. They will also build a prototype model to predict dominant routes of exposure based on chemical characteristics. With two samplers per participant, up to 60 samples will be screened to create a dataset of personal exposures. This will lay the foundation for developing robust exposure models to further the goals of the Environmental Health program.

Abstract

Silicone wristbands (swbs) are a relatively new personal sampling approach but have been increasingly used as personal passive samplers in over 25 publications representing over 1000 participants and 100S of detected chemicals in the short time they have been available. Using swbs is appealing because they are easy to wear, have a wide range of potential capture, and do not require training, energy or maintenance. However, the effect and magnitude of skin/sweat/contact exposure versus air exposure when reporting chemical data from swbs is not well understood. This application will help distinguish direct contact from atmospheric exposures and help predict dominant exposure routes for individual chemicals. Helping to predict chemical uptake and likely routes of exposure among multiple chemical classes will impact public health by dramatically increasing the efficiency of mitigating strategies, risk assessment and study of the exposome and how IT impacts human health outcomes. Traditional methods of capturing personal exposures typically represents a single route of exposure and captures a specific chemical or set of chemicals. In contrast, silicone is a polymer well suited to capture a wide range of organic chemistry and swbs can capture compounds dermally or through direct contact in addition to atmospheric sources. The resulting data from swbs therefore represents a complex exposure profile that is often more relevant to internal dose for certain compounds. However, the additional capacity of wristbands absorbing chemicals from non-atmospheric sources is not yet easily characterized or predicted. Physicochemical parameters have been used previously to help predict atmospheric uptake for different chemicals. The proposed research will use SWB data and physicochemical parameters to build a prototype of a model that helps predict dominant routes of exposure. Swbs will be used in paired configurations ("traditional" and an "air-only" configuration) that will help compare routes of exposure and will be analyzed for over 1500 chemical compounds including pesticides, flame retardants, polycyclic aromatic hydrocarbons, phthalates, fragrances and additives in personal care products, food-related chemicals such as nicotine and caffeine, and chemicals associated with industry like plasticizers. There are two aims to this proposal: 1) utilize multiple silicone wristband configurations in a field demonstration of atmospheric and contact absorption with a 1500 chemical screen among a maximum of 30 individuals, and 2) build a prototype of an uptake model that predicts dominant routes of exposure for chemicals based on their inherent characteristics. With two samplers for every participant, up to 60 samples will be screened for 1529 organic chemicals representing a rich dataset of personal exposures. This will serve as a good foundation to begin building robust exposure models.