Abstract—This study aims to investigate the concentration,
lifetime cancer risk, and hazard index of trihalomethanes
(THMs) through oral ingestion, dermal absorption and
inhalation exposure from tap water of 17 community water
treatment plants in northeastern Thailand. Chloroform
(CHCl3) was found at highest level compared to
dichlorobromomethane (CHCl2Br), chlorodibromomethane
(CHClBr2) and bromoform (CHBr3) species. Results revealed
that the Chongsammoe water treatment plant in Chaiyaphum
province was found in the highest levels of 48.46 μg/L for total
THMs whereas the levels were below the water quality
guideline of WHO. Among the three pathways studies, the
highest lifetime cancer risk comes from oral ingestion followed
by dermal absorption and inhalation exposure route, mainly
because of the exposure to CHCl3. Overall 6 of 17 plants, the
lifetime cancer risk for CHCl2Br and CHCl3 through oral
ingestion route were higher than risk level of 10-6 , the negligible
defined by the USEPA. The average hazard index of total
THMs in all muti-pathway exposure routes was lower than 1
indicating to acceptable non-carcinogenic risk level.
Index Terms—Cancer risk assessment, trihalomethanes,
Thailand, water supply.
Prapat Pentamwa, Benchamaporn Sukton, and Tanisa Wongklom are
with the School of Environmental Health, Institute of Medicine, Suranaree
University of Technology, Nakorn Ratchasima, 30000 Thailand (e-mail:
prapat@sut.ac.th, ben_sukton@hotmail.com, koryaa_0332@hotmail.com).
Sathaporn Pentamwa is with the Health Center 5, Department of Health,
Ministry of Health, Nakorn Ratchasima, 30000 Thailand (e-mail:
sathapornounchit@hotmail.com).
Cite:Prapat Pentamwa, Benchamaporn Sukton, Tanisa Wongklom, and Sathaporn Pentamwa, "Cancer Risk Assessment from Trihalomethanes in Community Water Supply at Northeastern Thailand," International Journal of Environmental Science and Development vol. 4, no. 5, pp. 538-544, 2013.