EVALUATION OF AROMATIC HYDROCARBONS IN SOIL AND GROUNDWATER AT A GAS STATION IN THE CITY OF NATAL/RN-BRAZIL

• DOI: https://doi.org/10.22533/at.ed.3174272407119

• Palavras-chave: Aromatic hydrocarbons, Benzene, Groundwater, Environmental contamination, Fuel stations.

• Keywords: Aromatic hydrocarbons, Benzene, Groundwater, Environmental contamination, Fuel stations.

• Abstract:

  Fuel retailing stations are economically important activities, but they are classified as potential sources of pollution and environmental accidents, presenting significant risks of contamination of ground and surface water resources, soil and the atmosphere. This study develops a case analysis of contamination at a gas station located in the city of Natal, RN, Brazil, using BTEX compounds (benzene, toluene, ethylbenzene and xylenes) and polyaromatic hydrocarbons (PAHs) as markers of environmental contamination. Gas chromatography techniques with different detectors were used to identify and quantify the hydrocarbons: gas chromatography with a flame ionization detector coupled to a photoionization detector for BTEX and gas chromatography coupled to mass spectrometry for PAHs. It was found that benzene concentrations in soil ranged from 1.164 to 4.503 mg.Kg-1 , while in groundwater samples the values ranged from 12.097 to 27.638.6 µg.L-1 . Among the PAHs, naphthalene and anthracene stand out, with soil concentrations ranging from 0.420 mg.Kg-1 to 15.46 mg.Kg-1 and 0.110 mg.Kg-1 to 0.970 mg.Kg-1 , respectively. In the groundwater samples, naphthalene showed values between 0.759 and 614.7 µg.L-1 . The results obtained were compared with the limits established by CONAMA Resolution 420, showing that the concentrations of benzene substantially exceed the maximum value allowed by Brazilian legislation. This is particularly relevant given that approximately 70% of Natal's water supply comes from underground sources.