Six Classes
We can reduce harmful chemicals
for a healthier world.
Periodic table of elements
2
9
F
17
Cl
35
Br
Six classes
1. Highly fluorinated chemicals
water and oil repellants, surfactants…
2. Antimicrobials
triclosan, triclocarban…
3. Flame retardants
brominated, chlorinated, phosphate
4. Bisphenols and phthalates
plastic additives…
5. Organic solvents
benzene, methylene chloride...
6. Certain metals
lead, mercury, chromium, cadmium, arsenic…
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Six Classes
1. Highly Fluorinated Chemicals
(Fluorochemicals)
Dr. Jennifer A. Field
Department of Environmental and Molecular Toxicology
Oregon State University
Corvallis, Oregon 97331
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Chemical Personality and C-F bonds
• Atoms share electrons in the form of bonds that glue molecules
together
• C-F bonds are the strongest bonds in nature
• Unique properties
• oil and water repellency
• resistance to breakdown in the environment and under
harsh conditions
O
O
PFOS
F
S
F
C
C
F
F
F
F
F
C
F
F
C
F
F
F
C
C
F
C
F
F
F
-
O
C
F
C
F
C
F
F
F
C
F
F
C
F
F
C
O
C
F
F
-
F
F
PFOA
O
C
F
C
F
C
F
F
F
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Fluorochemicals
• Do not occur in nature; only due to manufacture,
use, and disposal
• C8 forms (PFOS and PFOA) are of particular interest
• Produced in large quantities since 1940s
• Well studied
• Associated with wide range of human health
problems
• C4/C6 produced since the 1940s and share family
structure and properties, but almost no information
on health effects
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Where Fluorochemicals are Used
•
•
•
•
•
•
•
Carpeting
Upholstery
Apparel
Waxes (ski and floor)
Food packaging materials
Non-stick cookware
Dental floss
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Pathways to the Environment
Indoor and Outdoor Air
• Semi-volatile forms migrate out from products
• Higher indoor air concentrations move outdoors
Surface and Ground Water
• Industrial discharge
• Wash-off from treated apparel
• Wastewater treatment does not remove PFOS/PFOA
or shorter-chain analogs
Solid Waste Disposal
• Treated materials sent to landfills
• Liquid waste (leachates) sent to wastewater
treatment plants or percolate into ground
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Sources and Exposure Pathways
breastmilk
dust/fibre
goods
cord blood
Human exposure
PFAS producers/
PFAS-using factories
Prenatal/infant
exposure
Landfill
leachate
manufacturer waste
solid
WWTP
liquid
Adapted from Oliaei 2013, Environ Pollut Res
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Found Globally Today
• Surface Waters (lakes, rivers, ocean)
• Sediments & soils
• Groundwater (drinking water source)
• Air, Rain, Snow in urban and remote locations
• Marine and land-based wildlife
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Human Toxicology
• PFOS and PFOA persist in the body for years
• Health effects linked to exposure to PFOA:
• Kidney, prostate, ovarian, and testicular cancer
• Thyroid disease
• Delayed puberty, decreased fertility (women)
and early menopause
• Reduced testosterone levels
• Reduced immune response in children
• Elevated cholesterol
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PFOS and PFOA Replacements
• Shorter chains (C4/C6) offered as ‘alternatives’ but are
members of the PFOS/PFOA families or close cousins
• C4/C6 now found in surface waters, groundwater,
wastewater, & seawater
• C4/C6 not bioaccumulative but
are persistent, which is a ‘family trait’
• Very limited toxicology data on
short chain (C4/C6) family members
- Increasing C6 levels in human blood
- Causes changes in cells associated
with tumors
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Take Home Points
• Once produced, fluorochemicals stay on the planet
for a very, very long time.
• Widespread contamination of water, food, and soils;
distributed globally by air and water circulation.
• Current understanding of human health effects
developed for only PFOS & PFOA.
• Changing to other forms such as C6 and C4 may
appear as a quick fix for the marketplace but there
is no data to show they are safer.
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What can we do to reduce harm?
• Do we need them for performance/protection in all
current applications?
–Apparel
–Carpeting
–Food packaging
• Support research to find safer alternatives
–Materials innovation taking a page from nature
(bio-mimicry)
–Green chemistry
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Follow-up questions
– Are there fluorochemicals in the products you
manufacture, sell, or use?
– What functions do they serve?
– How necessary are these functions?
– What alternatives have you investigated?
– Would you be interested in continuing this
discussion?
If so, contact:
Erika Houtz, [email protected]
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