TY - JOUR
T1 - Dissolved organic nitrogen as a precursor for chloroform, dichloroacetonitrile, N-nitrosodimethylamine, and trichloronitromethane
AU - Lee, Wontae
AU - Westerhoff, Paul
AU - Croué, Jean Philippe
PY - 2007/8/1
Y1 - 2007/8/1
N2 - Nitrogen-containing disinfection byproducts (N-DBPs) are potentially toxic. This study assessed the formation of three N-DBPs (dichloroacetonitrile (DCAN), trichloronitromethane (TCNM), and N-nitrosodimethylamine (NDMA)) and one regulated DBP (chloroform) upon adding free chlorine and monochloramine into solutions containing different fractions (hydrophobic, transphilic, hydrophilic, and colloidal) of dissolved organic matter (DOM) isolates (n = 17). We hypothesized that N-DBP formation would increase for organic matter enriched in organic nitrogen. Formation potential tests were conducted with free chlorine or preformed monochloramine. Chloramination formed, on average, 10 times lower chloroform concentrations, but 5 times higher DCAN concentrations, as compared with free chlorine addition. The formation of the two halogenated N-DBPs (DCAN and TCNM) increased as the dissolved organic carbon (DOC) to dissolved organic nitrogen (DON) ratio decreased upon adding free chlorine, but the N-DBP formation was relatively constant upon adding monochloramine. NDMA, a nonhalogenated N-DBP, formed on average 0.26 nmol per mg of DOC (4.5 nmol per mg of DON) upon adding monochloramine; no NDMA formation occurred upon adding free chlorine. NDMA formation increased as the DOC/DON ratio decreased (i.e., increasing nitrogen content of DOM). NDMA formation also increased as the amino sugar to aromatic ratio of DOM increased. The results support the hypothesis that DON promotes the formation of N-DBPs.
AB - Nitrogen-containing disinfection byproducts (N-DBPs) are potentially toxic. This study assessed the formation of three N-DBPs (dichloroacetonitrile (DCAN), trichloronitromethane (TCNM), and N-nitrosodimethylamine (NDMA)) and one regulated DBP (chloroform) upon adding free chlorine and monochloramine into solutions containing different fractions (hydrophobic, transphilic, hydrophilic, and colloidal) of dissolved organic matter (DOM) isolates (n = 17). We hypothesized that N-DBP formation would increase for organic matter enriched in organic nitrogen. Formation potential tests were conducted with free chlorine or preformed monochloramine. Chloramination formed, on average, 10 times lower chloroform concentrations, but 5 times higher DCAN concentrations, as compared with free chlorine addition. The formation of the two halogenated N-DBPs (DCAN and TCNM) increased as the dissolved organic carbon (DOC) to dissolved organic nitrogen (DON) ratio decreased upon adding free chlorine, but the N-DBP formation was relatively constant upon adding monochloramine. NDMA, a nonhalogenated N-DBP, formed on average 0.26 nmol per mg of DOC (4.5 nmol per mg of DON) upon adding monochloramine; no NDMA formation occurred upon adding free chlorine. NDMA formation increased as the DOC/DON ratio decreased (i.e., increasing nitrogen content of DOM). NDMA formation also increased as the amino sugar to aromatic ratio of DOM increased. The results support the hypothesis that DON promotes the formation of N-DBPs.
UR - http://www.scopus.com/inward/record.url?scp=34547679717&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34547679717&partnerID=8YFLogxK
U2 - 10.1021/es070411g
DO - 10.1021/es070411g
M3 - Article
C2 - 17822121
AN - SCOPUS:34547679717
SN - 0013-936X
VL - 41
SP - 5485
EP - 5490
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 15
ER -