Seasonal Variation of Trihalomethanes Levels in Greater Cairo Drinking Water

Abstract

The formation of carcinogenic Trihalomethanes (THMs) in the process of water disinfection by chlorine has raised concerns in the scientific community. This study aims to determine the levels of THMs in Greater Cairo drinking water over year of the study and compare it with the regulation in the Egypt law (458/2007), and the World Health Organization. The THMs concentration was measured in five different locations during 2014. The results indicate that the seasonal variation is below the critical values stipulated in the state, WHO and Egyptian regulations (seasonal average 45.14 ± 9.23 µg/l). In conclusion, it can be inferred that the concentration of THMs in the drinking water of Greater Cairo is not hazardous to human health.

Presence and seasonal variation of trihalomethanes (THMs) levels in drinking tap water in Mostaganem Province in northwest Algeria

“…Depending on trihalomethanes concentration evolution during all months for the year 2015, primarily, July shows the highest concentration of total THMs in all sample points except in Beymouth city which scored a rate of 21.95 μg/L and remains lower compared to other sampling sites; and secondly, the month of September which marked interesting rates for all sample points; On the other hand, it was observed that in the month of March, the rate of total trihalomethane is slightly higher than in December, with 134.4 μg/L and 126.65 μg/L respectively. Our results are in accordance with those found in the United States, Europe and Egypt (17–20) indicating that the water temperature decreases in winter, which is a disadvantage in the production of the disinfection by-products while the concentration of THMs increases in summer and autumn sees the temperature rise depending on the season and the emissive use of chlorination to ensure safe water (21, 22). These results have proved the dominance of brominated species in all the samples analyzed, whereas chlorinated species like chloroform (CHCl3) and bromodichloromethane (CHBrCl2) were not detected on some of the sample points (0.00 μg/L) or have marked low levels in others, which is illustrated in Table 1, for example the Achaacha sample had the highest total trihalomethanes (198 μg/l) in July.…”