PFCs might last in the environment forever...

















PFCs have become global pollutants in a short period of time.

They are found in remote islands, forests, and polar regions.



They are more persistent in the environment than PCBs and DDT.

They bioaccumulate.

They are toxic.



They are now found in every person tested.

U.S. residents have the world's highest PFC burdens.





Perfluorinated chemicals are popular for their non-stick and stain-repellant qualities.


The most recognizable are

Polytetrafluoroethylene	PTFE, Teflon™
Perfluorooctanoic acid	PFOA, C8
Perfluorooctane sulfonic acid	PFOS

Nearly 100 PFCs are known.

These include manufacturing precursors, process intermediates, and breakdown products.



Examples are fluorotelomer alcohols (FTOHs) and perfluorinated carboxylic acids (PFCAs or PFAs).

PFOS and PFOA receive the most attention.




PFCs have not been adequately studied in regards to toxicity.

Still, the following picture is emerging.




PFCs are especially toxic to developing fetuses and newborns.

The developmental neurotoxic effects of PFCs are similar to those reported for PCBs and PBDEs.



PFOA crosses the placenta unhindered into the fetus, and PFOS is only slightly hindered.

Other PFCs cross the placenta as well.

Some research suggests there is an interactive effect between maternal stress and prenatal exposure to PFCs.



The rate of neonatal survival corresponds to maternal PFC burden.




PFCs are now found in the cord blood of every newborn tested.



There is an association between cord serum concentration and low birth weight and size.



In some cases a deficit in postnatal weight gain becomes a wasting syndrome.




PFCs are teratogenic — prenatal exposure can result in miscarriage and birth defects.



Sometimes offspring are born with enlarged livers, under-developed lungs, or problems with vision.



Cancers may develop relatively early in life, especially liver and testicular.




A contaminated mother exposes her child first during gestation and then again while nursing.


PFCs can alter a mother's milk protein gene expression and stunt her daughter's mammary gland development.




Once inside the body, the half-life for excretion is roughly 4 years.



That means after 4 years only half is eliminated.

After 16 years more than 5% of the original exposure is still in the body.



But exposure happens daily.

That means people will carry PFC burdens for life.



Also, newborns have considerably less ability to eliminate PFCs.

So the most vulnerable population also retains the most.



To the extent that PFCs do deteriorate inside the body, the break down products appear to be more toxic.




PFCs are potent disruptors of gene expression.

A dose of 10 mg/kg per day — just 10 ppm — alters the expression of over 800 genes.



Many of these genes involve





Adverse effects reported with PFCs can be traced back to these disruptions.



For instance, suppressed expression of cell adhesion proteins can result in changes to the cell membrane.

Membrane permeability is one of the effects seen when cells are exposed to PFCs.




PFCs cause immune system damage.



Pre-natal exposure to PFCs can cause deficits in innate and humoral immunity.



PFC exposure can increase allergic sensitivity to egg white.

It may increase the IgE response to environmental allergens in general.



PFCs disrupt digestive activity which also has a downstream effect on immune function.




Some of the most striking effects involve hormone regulation.



PFCs are endocrine disruptors.

Evidence suggest they may interface directly with estrogen receptors.



Observed effects include

• Incorrect differentiation between male and female during gestation
• 
  
• Alterations in the physical structure of testes
• 
  
• Increased estrogen and decreased testosterone — but early puberty in males and not females
• 
  
• Changes in thyroid function
• 
  
• Altered cholesterol levels
• 
  
• Neuroendocrine disruption

In general, many toxics are lipophilic (fat loving) and are bound up in adipose (fat) tissue.



One curious effect of PFC exposure is the atrophy of adipose tissue.



Toxicants are released when fat cells degenerate.

This elevates the concentration of of toxicants circulating throughout the body.



Consequently, PFC exposure can trigger illnesses caused by toxicants other than itself.






PFCs are excitotoxic.








PFCs are neurotoxic to Purkinje (brain) cells.






Methylated forms of PFCs interfere with mitochondrial metabolism.


Observations include






Other effects have yet to be confirmed, but finding them will not be a huge surprise.


For instance, diabetes and certain forms of cancer are associated with derangement of the G-protein signaling pathways suppressed by PFCs.


Note that liver cancer, testicular cancer, and glioblastoma multiforme (GBM) tumors have already been associated with PFCs.




PFCs are familiar by trade names such as






PFCs are used in a very broad range of products.


Many of the items off-gas the chemicals constantly.


Indoor air is filled with PFCs.








PFOS has been observed to enhance the toxicity of clophosphamide (CPP), a cancer drug similar to mustard gas.


Further research is required to discover additional synergistic toxicity between PFCs and other chemicals.




Wastewater plants are not designed to treat PFCs.

Neither are municipal drinking water treatment facilities.

The PFCs just stream right through.



Experiments show that reverse osmosis (RO) filtration is >99% effective at rejecting PFOS.



But RO is not considered a practical large scale solution for municipal water treatment plants.

Currently there are no successful solutions for water treatment facilities to remove PFCs.




PFOA and PFOS are not broken down by heat, light, or microbes.



Other PFCs can break down but most of them end up giving off PFOA or PFOS in the process.



For example, PTFE (Teflon) is a complex mixture of PFCs.

It releases toxic gases including PFOA when heated.



PFCs have been detected when cookware reaches 446°F (a medium heat).

Heated non-stick coatings have been reported to kill pet birds at 396°F.

That means toxic fumes begin releasing at even lower temperatures.



Humans can experience a severe flu-like illness named polymer fume fever.



Frequent use of non-stick cookware at high temperatures will cause the coating to breakdown quickly.

Dishwashing detergents can also accelerate the process.



All perfluorinated cookware is similarly hazardous regardless of the brand name or marketing claims.

The difference between brands stems from the proportion of PTFE blended with other materials.




3M began to phase out PFOS from its ScotchGaurd fabric protector and other products in 2000-2002.



In January 2006 DuPont and other companies volunteered to phase out the use of PFOA.

However, the target for withdrawal is 2015 and it is not binding.



The EPA has not added PFOA to its Toxics Release Inventory

It has no timetable for doing so.



To learn more about PFCs, consider these starting points

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