Graduation Year


Document Type




Degree Granting Department

Public Health

Major Professor

Foday M. Jaward, Ph.D.

Committee Member

Thomas L. Crisman, Ph.D.

Committee Member

Ricardo Izurieta, M.D., Dr.PH, MPH


Air Samples, Congeners, Passive Air Sampling, PBDEs, Persistent Organic Pollutants


Polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in a number of common household and commercial products around the world. PBDEs enter the environment in a variety of ways, such as through emissions, leaching from end-of-life electronics in landfills, and incineration. While many countries have phased out the manufacturing of penta-, octa-, and deca-PBDEs or have banned the manufacture and use of these congeners altogether, these persistent organic pollutants (POPs) continue to be detected in humans and the environment.

This study investigates spatial and temporal variations of selected PBDEs in the air of the Nandamojo watershed area in Costa Rica by comparing air concentrations of PBDEs in the dry winter vs. wet summer seasons and rural vs. urban areas and also investigates the impact of anthropogenic activities on air concentration of PBDEs. This study is significant to the field, because there are no baseline studies nor are there currently any monitoring programs to assess the environmental levels of PBDEs or other POPs for this region of the Guanacaste province. Baseline information is needed to track spatial and temporal trends as well as evaluate the effectiveness of control measures employed nationally and internationally.

Samples obtained from passive air sampling devices were analyzed via GC/MS for a number of congeners. PBDE-47 and -99 were found to be the congeners present in greatest concentration in air samples from the Nandamojo watershed area. Air concentrations were estimated assuming an average sampler uptake rate of 3.5 m3/day and ranged as follows: ΣPBDE5 35.20-1549.25 pg/m3 over the entire study. The presence of PBDEs in remote and pristine environments indicates that PBDEs are now a global concern.

This study suggests that the spatial and temporal distribution patterns observed are strongly related to anthropogenic activities and presence of a population similar to that observed in other studies. The presence of PBDEs has become a global issue and, as such, these results provide background information on air concentrations of PBDEs for use in a global-scale multimedia model. In order to monitor PBDEs globally, it is imperative to implement and/or expand surveillance programs internationally.