Monitoring nitrogen dioxide (NO2) concentration in Creek Town, Cross River State, Nigeria. – R. A Etiuma, I. E. Uwah and A. U. Etiuma
Measurement of nitrogen dioxide (NO2) in Creek Town, Cross River State was carried out. Ambient NO2 concentration was determined bi-weekly from June to September using diffusion tubes. A triethanolamine (TEA) coated mesh present in the diffusion tubes trapped the NO2 which was determined colorimetrically as nitrite with saltzman reagent. The concentration obtained ranged from 5ppb to 185 ppb. Some of the concentrations were higher than the Federal Environmental Protection Agency (FEPA) limit of 40-60 ppb.