Persistent organochlorine residues in human breast milk from Hanoi and Hochiminh City, Vietnam: contamination, accumulation kinetics and risk assessment for infants.
Despite the ban on persistent organochlorines (OCs) in most of the developed nations, their usage continued until recently in many Asian developing countries including Vietnam, for agricultural purposes and vector-borne disease eradication programs. In this study, we collected human breast milk samples from the two big cities in Vietnam: Hanoi (n=42) and Hochiminh (n=44) and determined the concentrations of persistent OCs such as PCBs, DDT and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), chlordane compounds (CHLs) and tris-4-chlorophenyl-methane (TCPMe). The contamination pattern of OCs was in the order of DDTs > PCBs > HCHs > CHLs approximately HCB approximately TCPMe. Compilation of available data indicated that DDT residue levels in human breast milk from Vietnam were among the highest values reported for Asian developing countries as well as developed nations. This result suggests recent usage of DDTs in both north and south Vietnam. Interestingly, in both cities, the p,p'-DDT portion was higher in multiparas than those in primiparas. Considering the fact that the interval between the first and the second child of a mother in Vietnam is usually short, this result probably indicates continuous intake of DDTs in the population. Analysis of infant exposure to DDTs via breast milk suggested that the daily intake rates for number of individuals are close to or above the threshold for adverse effects which may raise concern on children health.
Minh
Nguyen Hung
NH
Center for Marine Environmental Studies, Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan.
Someya
Masayuki
M
Minh
Tu Binh
TB
Kunisue
Tatsuya
T
Iwata
Hisato
H
Watanabe
Mafumi
M
Tanabe
Shinsuke
S
Viet
Pham Hung
PH
Tuyen
Bui Cach
BC
D000367:Age Factors; D002706:Chlordan / Q000032:analysis / Q000493:pharmacokinetics; D003634:DDT / Q000032:analysis / Q000493:pharmacokinetics; D003906:Developing Countries; D002658:Developmental Disabilities / Q000139:chemically induced; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D001556:Hexachlorocyclohexane / Q000032:analysis / Q000493:pharmacokinetics; D006801:Humans; D007223:Infant; D007306:Insecticides / Q000032:analysis* / Q000493:pharmacokinetics; D008895:Milk, Human / Q000737:chemistry*; D010298:Parity; D010573:Pesticide Residues / Q000032:analysis* / Q000493:pharmacokinetics; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000493:pharmacokinetics; D018570:Risk Assessment / Q000379:methods; D014744:Vietnam
D007306:Insecticides; D010573:Pesticide Residues; D002706:Chlordan; D001556:Hexachlorocyclohexane; D003634:DDT; D011078:Polychlorinated Biphenyls