Grantee Research Project Results

2004 Progress Report: Children's Vulnerability to Environmental Immunotoxicant Exposure

EPA Grant Number: R830758
Title: Children's Vulnerability to Environmental Immunotoxicant Exposure
Investigators: Grandjean, Philippe , Weihe, Pal
Institution: Harvard University
EPA Project Officer: Aja, Hayley
Project Period: May 5, 2003 through May 4, 2006 (Extended to May 4, 2007)
Project Period Covered by this Report: May 5, 2004 through May 4, 2005
Project Amount: $750,000
RFA: Children's Vulnerability to Toxic Substances in the Environment (2002) RFA Text |  Recipients Lists
Research Category: Children's Health , Human Health

Objective:

The objective of this research project is to determine the immunotoxic risk in children exposed prenatally and postnatally to polychlorinated biphenyls (PCBs). Experimental animal studies with Aroclor 1254 used by the U.S. Environmental Protection Agency for calculating a Reference Dose (RfD) for PCBs suggest that immunotoxicity may be critical, but current exposures, especially those from breast-feeding, greatly exceed the RfD.

Progress Summary:

The project was started as planned, and the approved protocol has been followed without any necessary changes. Thus, the procedures for contacting subjects, informed consent, blood sampling, and clinical examination have not deviated in any way from the approved grant proposal. To date, the birth cohort followup for Year 5 is complete and has achieved the following accomplishments:

• The project cohort includes a total of 549 children who had a nitric-oxide synthase (NOS) examination at 2 weeks of age and data on mercury and persistent organic pollutants (POPs) exposure at birth.
• At age 5 years, 501 of the children participated in the follow-up examinations (91.3%).
• We obtained a blood sample (before vaccination) from 485 of the cohort members (88.3%).
• We subsequently obtained a blood sample 4 weeks after vaccinations from 398 of these children (82.1%).

The reasons provided (by the total of 48 nonparticipants) for not participating in the followup include:

• Moved to Denmark (20)
• Moved to Iceland (2), Greenland (1), and Spain (1)
• Retracted from the study, no reason revealed (14)
• Did not want to participate in the 5-year examination, though perhaps later on (8)
• Did not respond to the invitation letter (1)
• Fear of needles (1)

The hair samples have been transferred to the analytical laboratory in Denmark, and mercury analyses have been initiated. Vials from the first examination have been transferred to the analytical laboratory, which will conduct the antibody measurements. Antibody assessments have not yet begun because of the lack of capacity at the immunology laboratory. The same applies to the PCB analyses. Stored maternal pregnancy serum for arylhydrocarbon receptor activation assays has been transferred to the laboratory at Boston University, and the analyses have been initiated. Sample storage is otherwise maintained in the Faroes.

Although no results can be reported at this early stage, the project is moving forward as anticipated in accordance with the time schedule. The participation rates are considered highly satisfactory.

We recently received approval for continuation of our project through age 7 years from the Harvard School of Public Health’s Human Subjects Committee.

Future Activities:

Year 2 of the research project has been devoted to recruiting and examining the second half of our cohort, with additional studies (especially analyses of exposure biomarkers) being initiated, as outlined in the grant proposal. We will analyze the complete set of serum samples for specific antibodies and for PCBs during the following year. Data analysis will include careful evaluation of potential confounders (which are not expected to be of major importance) as outlined in the grant proposal, with bivariate associations, multiple regression analyses, and structural equation models.

Journal Articles:

No journal articles submitted with this report: View all 16 publications for this project

Supplemental Keywords:

cumulative effects, dioxin, dose-response, epidemiology, human health, hypersusceptibility, infants, marine food contamination, methylmercury, mixed exposure, prenatal exposure delayed response, risk assessment, sensitive populations,, RFA, Health, Scientific Discipline, PHYSICAL ASPECTS, INTERNATIONAL COOPERATION, ENVIRONMENTAL MANAGEMENT, HUMAN HEALTH, Health Risk Assessment, Physical Processes, Risk Assessments, Environmental Policy, Exposure, Children's Health, Biochemistry, Risk Assessment, dietary exposure, health effects, Human Health Risk Assessment, post-natal exposure, exposure model, pesticides, developmental toxicity, pesticide exposure, prenatal exposure, polychlorinated biphenyl, animal model, immunotoxicology, PCB, pregnant women, developmental effects, children's vulnerablity, children's environmental health, exposure assessment

Relevant Websites:

http://www.chef-project.dk/ Exit

Progress and Final Reports:

Original Abstract

2003 Progress Report

2005 Progress Report

Final Report