Exploring the Sources and Reactive Fate of Chemical Contaminants in Indoor Environments

Although we spend most of our lives in indoor environments, the degree of chemical exposure we obtain indoors is not well known. Moreover, as chemists, we are interested in the extent to which chemical contaminants undergo reactive chemistry in the spaces we inhabit.  Is the oxidizing capacity of the indoor environment sufficiently high that most contaminants react away before being ventilated outdoors?  Is indoor photochemistry fast or slow?  Motivated by these questions, this talk will highlight studies we have performed in both the laboratory and genuine indoor environments.  Part of our work involves emissions from common houseful products and activities, such as LCD screens and bleach cleaning.  Reactive chemistry studies involve oxidation of skin oil and its components, combustion products such as nicotine and THC (from cannabis), and unsaturated triglycerides. These oxidation reactions occur largely on indoor surfaces, via complex multiphase pathways. Ozone is the major oxidant but OH oxidation can initiate autoxidation pathways and HOCl is important when bleach cleaning occurs.  A common theme to this work is that the toxicity of many of the observed oxidation products is not well known, complicating our assessment of chemical exposure.