The atmospheric monitoring component of the 1993 Lower Rio Grande Valley Environmental Scoping Study measured a wide range of pollutant species from different sampling and analysis methods. Extensive QA/QC activities were also conducted on the sampling and analysis techniques, This enabled a unique comparison of these methods to provide insights into air sampling for larger, long-term exposure monitoring studies. Pollutants monitored were particulate mass and elements, acidic gases, volatile organic compounds, pesticides, and polycyclic aromatic hydrocarbons. This included collocated monitoring devices which monitored same-species pollutants, Sample collection efficiencies of certain atmospheric pollutants are discussed. Finally, data from two sites located in the Lower Rio Grande Valley are also presented and compared. Published by Elsevier Science Ltd.