Chemicals used to produce non-stick
cookware and waterproof fabrics may raise cholesterol levels in children and teens
Children and teens with higher blood levels of chemicals
used in the production of non-stick cookware and waterproof fabrics appear more
likely to have elevated total and LDL cholesterol levels, according to a report
in the September issue of Archives of Pediatrics & Adolescent Medicine, one
of the JAMA/Archives journals.
Humans are exposed to the man-made compounds known as
perfluoroalkyl acids-including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate
(PFOS)-through drinking water, dust, food packaging, breast milk, cord blood,
microwave popcorn, air and occupational exposure, according to background information
in the article. Recent national survey results reported detection of PFOA and
PFOS in almost all samples of human serum. Perfluoroalkyl acids are used during
the manufacture of fluoropolymers, which give non-stick heat resistance to cookware
and breathable, waterproof properties to fabrics and upholstery. PFOA and PFOS
may also result from the breakdown of compounds used as coating for commercial
food packaging, factory treatments for fabrics and carpets and manufacturer pretreatment
for stain-resistant clothing.
Animal studies have identified the liver as the primary organ affected by perfluoroalkyl
acid exposure, with potential effects in human including alterations in cholesterol
levels. Stephanie J. Frisbee, M.Sc., M.A., of West Virginia University School
of Medicine, Morgantown, and colleagues assessed serum lipid levels in 12,476
children and adolescents (average age 11.1) included in the C8 Health Project,
which resulted from the settlement of a class-action lawsuit regarding PFOA contamination
of the drinking water supply in the mid-Ohio River Valley.
After enrolling in 2005 or 2006, the children and teens submitted blood samples;
their average PFOA concentration was 69.2 nanograms per milliliter and average
PFOS concentration was 22.7 nanograms per milliliter. Among 12- to 19-year old
participants, PFOA concentrations were higher than those detected in a nationally
representative survey (29.3 nanograms per milliliter vs. 3.9 nanograms per milliliter),
but PFOS concentrations were similar (19.1 nanograms per milliliter vs. 19.3 nanograms
per milliliter).
After adjusting for related variables, higher PFOA levels were associated with
increased total cholesterol and LDL cholesterol, and PFOS was associated with
increased total cholesterol, LDL cholesterol and HDL cholesterol. There was no
association between either compound and triglyceride levels.
On average, the one-fifth of children and teens with the highest PFOA levels
had total cholesterol levels 4.6 milligrams per deciliter higher and LDL cholesterol
levels 3.8 milligrams per deciliter higher than the one-fifth with the lowest
PFOA levels. In addition, there was an average difference of 8.5 milligrams per
deciliter in total cholesterol levels and 5.8 milligrams per deciliter in LDL
cholesterol levels between the one-fifth of participants with the highest and
lowest PFOS levels.
"The non-linear nature of the observed associations, particularly for
PFOA, suggests a possible saturation point in an underlying physiologic mechanism,"
the authors write. "PFOA and PFOS specifically, and possibly perfluoroalkyl
acids as a general class, appear to be associated with serum lipids, and the association
seems to exist at levels of PFOA and PFOS exposure that are in the range characterized
by nationally representative studies."
Although the design of the study limits cause-and-effect interpretations, the
results suggest the association between PFOA and PFOS and elevated cholesterol
levels warrant further study, the authors note. "Should the association prove
to be etiologic, the cumulative effects of such an elevation in cholesterol on
long-term cardiovascular health are unclear given the early age at which these
associations were observed."
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