The length of time chemicals remain in the body varies from chemical to chemical and ranges from hours to decades. For chemicals that are excreted quickly, the fact that we can so consistently measure them indicates continual exposures that may have long-term effects on health.
Body Burden and Biomonitoring
Body burden refers to the levels of man-made chemicals in an individual’s body, generally measured through blood or urine. Large-scale biomonitoring programs that assess the levels of chemicals in a population or subset of a population would greatly support the ability of researchers to explore the links between exposures and disease. A gap in determining the long-term effects of chemical exposures upon disease has long been a lack of knowledge about chemical exposures and the intake of environmental toxins into the body. Ongoing biomonitoring programs would fill this vital data gap.
The Pollution in People
The largest U.S. body burden study to date measured the levels of 148 chemicals in approximately 3,000 people of varying ages, ethnicities and geographical locations (ii). This study, by the U.S. Centers for Disease Control, detected a common sunscreen ingredient, benzophenone-3 (BP-3) in 96.8 percent of individuals (iii), and triclosan, an antibacterial agent often used in antibacterial soaps, in 74.6 percent of individuals (iv). A CDC study found residues of four different phthalates in more than 75 percent of subjects (v). Phthalates are found in numerous cosmetics, often as a constituent ingredient of fragrances. A 2008 study of teen girls by the Environmental Working Group revealed 16 hormone-altering cosmetics chemicals in their young test subjects (vi).
The CDC tests of 148 chemicals represents a very small percentage of the over 80,000 chemicals manufactured and the approximately 10,000 chemicals used in cosmetic products. The next edition of the CDC report, anticipated in 2009, will include measurements of 250 chemicals, an increase that still doesn't approach the total number of chemicals in commerce. Nevertheless, this and other studies illustrate that chemicals we use in an array of consumer products make their way into our bodies (vii). This knowledge also furthers our understanding of the links between the chemicals we use, the absorption of these chemicals into our bodies, and the known and probable health effects of these chemicals.
i.Commonweal Biomonitoring Resource Center (2005). Taking It All In: Documenting Chemical Pollution in Californians through Biomonitoring. Available online at http://www.commonweal.org/programs/download/TIAI_1205.pdf. Accessed August 19, 2008.
Environmental Working Group (2006). Across Generations: Industrial Chemicals in Mothers and Daughters: The pollution we share and inherit. Available online at http://www.ewg.org/reports/generations/. Accessed August 19, 2008.
Environmental Working Group (2005). Body Burden: The Pollution in Newborns. Available online at: http://www.ewg.org/node/17686. Accessed August 19, 2008.
Environmental Working Group (2003). Body Burden: The Pollution in People. Available online at: http://archive.ewg.org/reports/bodyburden1/. Accessed August 19, 2008.
ii Centers for Disease Control and Prevention (CDC) (2005). Third National Report on Human Exposure to Environmental Chemicals. Available online at http://www.cdc.gov/exposurereport/. Accessed December 23, 2008.
iii Calafat AM, Wong LY, Ye X, Reidy JA, Needham LL. Concentrations of the Sunscreen Agent, Benzophenone-3, in Residents of the United States: National Health and Nutrition Examination Survey 2003-2004. Environ Health Perspect 116:893–897 (2008).
iv Calafat AM, Ye X, Wong LY, Reidy JA, Needham LL. Urinary Concentrations of Triclosan in the U.S. Population: 2003–2004. Environmental Health Perspectives, 116:303–307 (2008).
v Silva MJ, Barr DB, Reidy JA, Malek NA, Hodge CC, Caudill SP, Brock JW, Needham LL, Calafat AM. “Urinary Levels of Seven Phthalate Metabolites in the U.S. Population from the National Health and Nutrition Examination Survey (NHANES) 1999-2000,” Environmental Health Perspectives, 112(3): 331-338 (2004).
vi Sutton, R (2008). Teen Girls' Body Burden of Hormone-Altering Cosmetics Chemicals. Available online at http://www.ewg.org/reports/teens. Accessed October 10, 2008.
vii Commonweal and Breast Cancer Fund (2005). Taking It All In: Documenting Chemical Pollution in Californians through Biomonitoring. Available online at http://www.commonweal.org/programs/download/TIAI_1205.pdf. Accessed August 19, 2008.
Environmental Working Group (2006). Across Generations: Industrial Chemicals in Mothers and Daughters: The pollution we share and inherit. Available online at http://www.ewg.org/reports/generations/. Accessed August 19, 2008.
Environmental Working Group (2005). Body Burden: The Pollution in Newborns. Available online at: http://www.ewg.org/node/17686. Accessed August 19, 2008.
Environmental Working Group (2003). Body Burden: The Pollution in People. Available online at: http://archive.ewg.org/reports/bodyburden1/. Accessed August 19, 2008.
0 comments:
Post a Comment