Biological Monitoring for Exposure Assessment: Potential for Use in Studies of Adverse Reproductive Outcomes

1. Biological Monitoring for Exposure Assessment -Potential for Use in Studies of Adverse Reproductive Outcomes • PJE Quintana, San Diego State University Graduate School of Public Health • jquintan@mail.sdsu.edu

2. “Biomonitoring” is the assessment of human exposure to chemicals by measuring the chemicals or their metabolites in human specimens such as blood or urine. "Biomonitoring" consiste en el análisis de la exposición humana a los compuestos químicos por medio de la determinación de los mismos o sus metabolitos en muestras humanas, como sangre u orina. PJE Quintana, SDSU Exposure assessment using biological samples

3. The Second Report, January 2003, presents biomonitoring exposure data for 116 environmental chemicals (divided into age, gender, and race/ethnicity groups ) El Segundo Informe Nacional, enero de 2003, presenta los resultados del análisis de 116 compuestos químicos ambientales (según edad, sexo, y raza o grupo étnico). CDC's El Informe Nacional sobre la Exposición Humana a Compuestos Químicos Ambientales (National Report on Human Exposure to Environmental Chemicals)http://www.cdc.gov/exposurereport/sp_default.htm

4. CDC 2nd annual report (in your binder)

5. California Birth Defects Monitoring Programhttp://www.cbdmp.org/biologic.htm SAMPLE BANKING-The California Birth Defects Monitoring Program is pioneering the use of specimens from statewide screening programs. -Newborn screening. Infants routinely have blood taken from their heels to test for metabolic conditions. Several blood spots are blotted onto a filter paper. Many of our studies have used extra blood spots to search for genetic variants. -Midpregnancy screening. The State’s Expanded AFP program offers a blood test screening for birth defects to all expectant mothers around 15-18 weeks of pregnancy. -Beginning in January 2003, the California Birth Defects Monitoring Program will accrue and store over 90,000 of these unused blood samples per year. Once pregnancy outcome is known, we can test the blood to get clues about why some mothers had healthy children while other mothers had children with birth defects and mental retardation. Biologic banking/testing are powerful new tools for finding causes of birth defects.

6. Biological monitoring testing • Useful for • Exposure assessment at trimester of interest • Long half life compounds like Pb, DDT/DDE • Short half life compounds with ‘constant’ exposure (cotinine for secondhand tobacco smoke) • Genetic susceptibility (e.g. polymorphisms in protective enzymes GST Mu, theta, pi) • Less useful for • Exposure assessment of short half life compounds like many solvents, unless exposure very continuous • Compounds that need a special collection tube, so that routine samples may not be suitable (for example Cd) ......IDEA for discussion – should we try to test either routine or specially collected biological samples for evidence of maternal exposures