To report trihalomethane (THM) and haloacetic acid (HAA) concentrations in drinking
water, assess variations in these concentrations depending on source and over time,
and estimate individual intake during pregnancy.
Water taken from 33 representative points of the water supply network of the 25 municipalities
in the study area was analyzed from 2006-2008. Water drinking habits were recorded
using a questionnaire.
Mean total THM concentrations were 16.9 μg/L (standard deviation, 7.9), while the
mean value for the sum of concentrations of five HAA (monochloroacetic, dichloroacetic,
tricholoroacetic, monobromoacetic, and dicromoacetic acids) was 10.9 μg/L (standard
deviation, 4.9). Concentrations were lower in spring waters, which were only chlorinated,
compared with dam waters, which were subject to a complete purification treatment:
8.8 μg/L vs 19.1 μg/L (p<0.01) and 8.2 μg/L vs 11.7 μg/L (p<0.01). Concentrations
significantly increased with the number of deposits in the network and with their
rechlorination and were higher in the summer and fall. Mean intakes of total THM and
of the five HAA were lower in women supplied with spring water. Intakes differed depending
on supply reservoir.
Disinfection by-products in water are affected by water source, supply network structure,
and annual season. The mean intake of these products varies depending on the source
of drinking water. Mean intakes of all products were much lower than values recommended
by the World Health Organization.
Copyright © 2009 SESPAS. Published by Elsevier Espana. All rights reserved.