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environmental-epidemiology

Novel Exposure Assessment

Through air, water, consumer products, and food, we are exposed to a wide range of chemicals every day, which may impact our health. The EXPOSOME encompasses the totality of human environmental (i.e. non-genetic) exposures from conception onwards, complementing the genome. Through our faculty research and the Exposome Collaborative @ Johns Hopkins University, we are developing tools and technologies to conduct exposure assessment outdoors, indoors, and as wearable sensors.

Research Highlights


Determining potential chemical exposures from electronic cigarettes

Electronic cigarette (e-cig) use is increasing at an alarming rate, despite critical knowledge gaps on their toxicity and potential health effects. E-cig devices work by heating a mixture of chemicals (e-liquid) with a metallic coil to generate a fine aerosol that is inhaled by the user. Information on these chemicals is not typically disclosed by manufacturers. E-liquids comprise different proportions of propylene glycol, vegetable glycerin, nicotine, flavorings, and other chemicals (e.g. metals, phthalates, flame retardants), which, along with the chemicals that may be formed during the aerosol generation. We have found toxic metals in every sample analyzed, regardless of flavor or nicotine content. One concerning finding was that 50% of our samples had detectable levels of chromium (Cr), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) in e-liquid that had not been in contact with the heating coil. In addition to metals, our preliminary analyses showed over 500 compounds were detected in JUUL tobacco, mint and menthol-flavored e-cig aerosols, and only 53 were tentatively identified using online databases. This means that over 90% of the chemicals were not identified through online databases.

Evaluating low-cost sensor technology

We are evaluating how low-cost sensor technology can be used to evaluate neighborhood level variability in pollutant and greenhouse gas concentrations. To understand these processes at high spatiotemporal resolution and their implications for air quality and personal exposure, we built custom, low-cost air quality monitors that measure concentrations of contaminants relevant to human health and climate, including gases (O3, NO, NO2, CO, CO2, and CH4) and size-resolved (0.3-10 µm) particulate matter with ~45 units around the city of Baltimore. We will use this network data to evaluate spatial and temporal patterns in air pollution exposures and

Associated Faculty

 *Denotes faculty who are accepting PhD students.