This thesis explored new methods for understanding the fate and transport of halogenated organic contaminants in the environment. A theoretical method of hazard assessment of chemical mixtures containing large numbers of components was developed and its application illustrated using polychlorinated alkanes, toxaphene, and halogenated dibenzo-para-dioxins and furans. Partitioning properties predicted by high-throughput quantitative structure property relationships were used to locate mixture constituents on plots displaying equilibrium phase distribution in various environmental compartments and the potential for bioaccumulation and long range transport. Potentially hazardous components were identified graphically for more detailed assessments. The applicability of XAD-resin based passive air samplers (XAD-PAS) for studying neutral polyfluoroalkyl substances (nPFAS) in the atmosphere was tested empirically. XAD-PASs have sufficiently high uptake capacity to yield temporally averaged nPFAS concentrations over period as long as a year. When applied as part of the Global Atmospheric Passive Sampling network, nPFAS were found to be truly global contaminants.

This thesis explored new methods for understanding the fate and transport of halogenated organic contaminants in the environment. A theoretical method of hazard assessment of chemical mixtures containing large numbers of components was developed and its application illustrated using polychlorinated alkanes, toxaphene, and halogenated dibenzo-para-dioxins and furans. Partitioning properties predicted by high-throughput quantitative structure property relationships were used to locate mixture constituents on plots displaying equilibrium phase distribution in various environmental compartments and the potential for bioaccumulation and long range transport. Potentially hazardous components were identified graphically for more detailed assessments. The applicability of XAD-resin based passive air samplers (XAD-PAS) for studying neutral polyfluoroalkyl substances (nPFAS) in the atmosphere was tested empirically. XAD-PASs have sufficiently high uptake capacity to yield temporally averaged nPFAS concentrations over period as long as a year. When applied as part of the Global Atmospheric Passive Sampling network, nPFAS were found to be truly global contaminants.