Determination of the presence of total trihalomethanes (TTHM's) in water for human consumption, from groundwater in Guatemala City.

Abstract

This article presents part of the results of a broader work found in the reference of the research work whose objective was to evaluate if there is presence of total trihalomethanes (TTHM'S) in concentrations greater than 80 µg / L, in groundwater used consumption of Guatemala City population, where is reported that in two of the four sampling points there is the presence of TTHM's that exceed the maximum permissible limits -LMP- of 80 µg / L, according to the National Primary Drinking Water Regulations (EPA, 2009). It was shown that the increase in TTHM's is related to variations in pH, residual chlorine, contact time, electrical conductivity and dissolved solids; at higher concentrations of these parameters, the levels of TTHM´s increase. This análisis was performed in four points of the distribution network in the southern area of the city was analyzed, carrying out seven repetitions for each sampling point with a confidence interval of 95%. From the seven repetitions in each sampling point, the following data were obtained: sampling point No. 1, average total trihalomethanes = 63 µg / L, standard deviation = 5,22 µg / L, sampling point No. 2, average total trihalomethanes = 110 µg / L, standard deviation = 50 µg / L, sampling point No. 3, average total trihalomethanes = 80 µg / L, standard deviation = 13,34 µg / L, and sampling point No. 4, average total trihalomethanes = 212 µg / L , standard deviation = 60 µg / L, justifying that sampling points 1 and 3 are in the - LMP-, while sampling points 2 and 4 do not comply with the -LMP- according to the National Primary Drinking Water Regulations.