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The article doesn't mention whether or not these compounds are removed by using a filter (like a Brita filter). I know Brita filters don't remove fluoride norm

The article doesn't mention whether or not these compounds are removed by using a filter (like a Brita filter). I know Brita filters don't remove fluoride normally, but these compounds sound organic, which activated carbon usually does remove. Any idea whether standard filters remove this?

ohthanks 10y ago
There are no official treatment recommendations for PFNA, PFOA, PFOS that I know of but they can be treated with activated carbon, RO membranes or some combination. GAC seems to be pretty effective and you could feel pretty safe with a Brita filter, a multi-stage undersink system or a large whole house filter. The issue with chemicals like these and treatment is that without extensive testing there isn't much information about breakthrough rate and contact time and the relationship, so repeated testing is really the only way to know when you need to change media. Manufacture cartridge change recommendations generally are pegged to chlorine removal only, so a filter may deplete it's PFOA removal potential in a 1/10 the recommended change interval.
trendia 10y ago
Activated carbon can remove some, but not all [0]. > part from the commonly studied perfluoroocta noic acid (PFOA or C8) and perfluorooctane sulfonate (PFOS), eight additiona l PFASs were evaluated: perfl uorobutanoic acid (C4), perfluoro- pentanoic acid (C5), perfluorohexanoic acid (C6), perfluoroheptanoic acid (C7), perfluorononanoic acid (C9), perfluorodecanoic acid (C10), perfluorobutane sulfonate (PFBS), and perfluorohexane sulfonate (PFHS). > Regardless of the test ed (S-)PAC, C4 removal was negligible, while PFOS removal was essentially complete. PFAS removal increased with increasing perfluorinated carbon chain length, and for a given perfluorinated carbon chain length, sulfonates were more adsorbable than carboxylat es. tl;dr: long-chain PFAS are removed, while short-chain PFAS are hardly removed at all [0] http://www.waterrf.org/ExecutiveSummaryLibrary/4344_ProjectSummary.pdf http://www.waterrf.org/ExecutiveSummaryLibrary/4344_ProjectS...
KSS42 10y ago
This EPA page seems to imply that activated carbon would help remove it: https://www.epa.gov/ground-water-and-drinking-water/drinking-water-health-advisories-pfoa-and-pfos https://www.epa.gov/ground-water-and-drinking-water/drinking... ---------------- Can PFOA and/or PFOS be boiled out of my water? No; PFOA and PFOS cannot be removed by heating or boiling water. However, there are steps you and your drinking water system can take to limit your exposure.In some cases, drinking water systems may be able to reduce concentrations of perfluoroalkyl substances, including PFOA and PFOS, by closing contaminated wells or changing rates of blending of water sources. Alternatively, public water systems can treat source water with activated carbon or high pressure membrane systems (e.g., reverse osmosis) to remove PFOA and PFOS from drinking water. These treatment systems are used by some public water systems today, but should be carefully designed and maintained to ensure that they are effective for treating PFOA and PFOS. In some communities, entities have provided bottled water to consumers while steps to reduce or remove PFOS or PFOA from drinking water or to establish a new water supply are completed. Home drinking water treatment units are typically certified by independent third party organizations against ANSI (American National Standards Institute) standards to verify their contaminant removal claims. Some home filters remove impurities using activated carbon and reverse osmosis, which are the same technologies utilized by public water supply systems to remove PFOA and PFOS. However, there currently are no ANSI protocols for testing home treatment systems to verify that these devices effectively remove PFOA and PFOS or how frequently the filters should be changed in order to maintain removal efficiency. NSF International is currently developing such protocols.

ohthanks 10y ago

There are no official treatment recommendations for PFNA, PFOA, PFOS that I know of but they can be treated with activated carbon, RO membranes or some combination. GAC seems to be pretty effective and you could feel pretty safe with a Brita filter, a multi-stage undersink system or a large whole house filter. The issue with chemicals like these and treatment is that without extensive testing there isn't much information about breakthrough rate and contact time and the relationship, so repeated testing is really the only way to know when you need to change media. Manufacture cartridge change recommendations generally are pegged to chlorine removal only, so a filter may deplete it's PFOA removal potential in a 1/10 the recommended change interval.

trendia 10y ago

Activated carbon can remove some, but not all [0]. > part from the commonly studied perfluoroocta noic acid (PFOA or C8) and perfluorooctane sulfonate (PFOS), eight additiona l PFASs were evaluated: perfl uorobutanoic acid (C4), perfluoro- pentanoic acid (C5), perfluorohexanoic acid (C6), perfluoroheptanoic acid (C7), perfluorononanoic acid (C9), perfluorodecanoic acid (C10), perfluorobutane sulfonate (PFBS), and perfluorohexane sulfonate (PFHS). > Regardless of the test ed (S-)PAC, C4 removal was negligible, while PFOS removal was essentially complete. PFAS removal increased with increasing perfluorinated carbon chain length, and for a given perfluorinated carbon chain length, sulfonates were more adsorbable than carboxylat es. tl;dr: long-chain PFAS are removed, while short-chain PFAS are hardly removed at all [0] http://www.waterrf.org/ExecutiveSummaryLibrary/4344_ProjectSummary.pdf http://www.waterrf.org/ExecutiveSummaryLibrary/4344_ProjectS...

KSS42 10y ago

This EPA page seems to imply that activated carbon would help remove it: https://www.epa.gov/ground-water-and-drinking-water/drinking-water-health-advisories-pfoa-and-pfos https://www.epa.gov/ground-water-and-drinking-water/drinking... ---------------- Can PFOA and/or PFOS be boiled out of my water? No; PFOA and PFOS cannot be removed by heating or boiling water. However, there are steps you and your drinking water system can take to limit your exposure.In some cases, drinking water systems may be able to reduce concentrations of perfluoroalkyl substances, including PFOA and PFOS, by closing contaminated wells or changing rates of blending of water sources. Alternatively, public water systems can treat source water with activated carbon or high pressure membrane systems (e.g., reverse osmosis) to remove PFOA and PFOS from drinking water. These treatment systems are used by some public water systems today, but should be carefully designed and maintained to ensure that they are effective for treating PFOA and PFOS. In some communities, entities have provided bottled water to consumers while steps to reduce or remove PFOS or PFOA from drinking water or to establish a new water supply are completed. Home drinking water treatment units are typically certified by independent third party organizations against ANSI (American National Standards Institute) standards to verify their contaminant removal claims. Some home filters remove impurities using activated carbon and reverse osmosis, which are the same technologies utilized by public water supply systems to remove PFOA and PFOS. However, there currently are no ANSI protocols for testing home treatment systems to verify that these devices effectively remove PFOA and PFOS or how frequently the filters should be changed in order to maintain removal efficiency. NSF International is currently developing such protocols.