Tuesday, January 1, 2008
Private File Attachment:
This study describes the time trends of organochlorines [OCs; 14 polychlorinated biphenyls (PCBs) and 11 chlorinated pesticides] in umbilical cord plasma of newborns in a remote Canadian coastal population. 408 cord blood samples collected between 1993 and 2000 for PCBs, chlordanes, dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyl- trichloroethylene (DDE), hexachlorobenzene (HCB), and n-3 fatty acids were tested. Many details about the how and why of the study are included. according to Dallaire et. Al. these results show that prenatal exposure to persistent OCs has declined significantly between 1993 and 2000 in this population. Definition of Organochlorine: OC’s are defined as persistent chlorinated pesticides and polychlorinated biphenyls (PCBs). They are/were often sprayed on fields for agriculture and sometimes in residential gardens. These then are absorbed into fatty tissues of animals eventually making their way to apex predators and also human beings. Schwartz et al 1983; Moss 1997 and Muckle et al, 2001 all note this passing down of PCB’s. Adjusted mean concentrationsa (and 95% confidence interval) of contaminants in cord blood by the year of birth are listed in table 2. Statistical analysis and results are discussed. To the estimation of Dallaire et al 2002, this is the first study of OC’s in prenatal exposure in history which could make it highly useful for scholarly works. The results of the study indicated that the amount of prenatal contamination of OC’s has been in decline and is continuing to decline, especially as the use of these is reducing.