The document discusses perspectives on PFAS fate, risk, and screening levels from Hawaii. It summarizes PFAS contamination at a Maui airport, where two areas were tested - a fire training area and a downgradient area. The fire training area has higher levels of less mobile PFAS like PFOS, while the downgradient area is dominated by more mobile PFAS like PFHxA. This indicates there may be one or two sources and different PFAS compositions in the source area versus the leading edge of the plume. The plume fails aquatic toxicity action levels and drinking water action levels are also exceeded, requiring further monitoring of wells, springs, etc.
Per- and Polyfluoroalkyl Substances (PFAS) Panel - Michael Honeycutt, Amber B...TWCA
The document provides information on a panel discussion at the 2019 TWCA Fall Conference on Per- and Polyfluoroalkyl Substances (PFAS). The panel will include three speakers: Michael Honeycutt of TCEQ discussing PFAS health effects and regulation; Jeffrey Wood of Baker Botts on PFAS regulatory, legislative, and litigation updates; and Amber Batson of CDM Smith on PFAS fate at utilities. The document provides background information on PFAS including uses, exposure, toxicity, and regulatory perspectives.
Toward a comprehensive global database of Per- and Polyfluoroalkyl Substance...OECD Environment
This document summarizes the creation of an updated, comprehensive list of per- and polyfluoroalkyl substances (PFASs) that may have been on the global market. Over 4,700 CAS numbers were identified from various sources and categorized. There are limitations due to information gaps and challenges in categorization. Opportunities for developing this list further include creating an online database that can be regularly updated, addressing knowledge gaps, and expanding the PFAS terminology through cooperation.
Eu actions to regulate Per- and Polyfluoroalkyl SubstancesOECD Environment
On Tuesday 25 February 2020, Eeva Leinala of the OECD Environment Directorate and Valentina Bertato of the DG Environment, European Commission presented the European Union's actions to regulate PFASs. It covered recent actions for restricting PFASs compounds and a strategy moving forward. This webinar is part of a series aiming to share information on issues related to PFASs and support a global transition towards safer alternatives.
This slideshow describes the forensic signatures of Per- and Polyfluoroalkyl Substances (PFAS) in surface water and groundwater based on literature data and contaminated fate & transport processes.
It includes slides presented by Andrew Cohen at the Emerging Contaminants Program Meeting, Environmental Business Council of New England, May 2, 2019.
Wellington Laboratories has been committed to providing high quality reference standards and exceptional customer service since its inception in 1980.
The primary source of Standards for EPA Methods 23, 513, 1613, 1668, 8280, 8290, European Method EN-1948 and World Health/EPA Standards, C13 and Native Dioxins, Furans, PCBs and Brominated Diphenyl Ethers, Brominated Dioxins and Furans, Methylated PCDDs and PCDFs, Fluorinated Compounds and more. Wellington Laboratories' offer a large range of native and mass-labelled per- and poly-fluorinated compounds.
PFAS (per- and polyfluoroalkyl
substances), known as “forever
chemicals” are found in everyday
objects. Food Packaging, paints,
cosmetics, wood lacquers, sealants ,
solar panels, fire fighting foams,
artificial grass and many more
seemingly innocent products.
Generally used to prevent corrosion
and make products waterproof and
stain-resistant they are present in our
everyday life. Unfortunately they do
not break down in our environment
and as a consequence are “forever
present”. Greyhound Chromatography provides a wide range of Chromatography related products for testing and analysis of PFAS and many other 'forever chemicals'.
This document summarizes a presentation on assessing the hazards of fluorinated alternatives to long-chain PFASs. It notes that industry has largely replaced long-chain PFASs with short-chain PFASs and perfluoro(poly)ether moieties. However, there is little information on many of the new alternatives. While short-chain PFASs have lower bioaccumulation than long-chain ones, they can still persist and contaminate drinking water aquifers for decades or centuries. The document concludes that a precautionary approach may be needed since all PFASs ultimately persist globally and contamination from them is poorly reversible, posing a potential planetary boundary threat.
Chemosphere 72 (2008) 1588–1593Contents lists available at S.docxchristinemaritza
Chemosphere 72 (2008) 1588–1593
Contents lists available at ScienceDirect
Chemosphere
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c h e m o s p h e r e
Removal of perfluorinated surfactants by sorption onto granular activated
carbon, zeolite and sludge
Valeria Ochoa-Herrera, Reyes Sierra-Alvarez *
Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ 85721-0011, USA
a r t i c l e i n f o a b s t r a c t
Article history:
Received 4 January 2008
Received in revised form 9 April 2008
Accepted 9 April 2008
Available online 3 June 2008
Keywords:
Adsorption
Biosorption
PFC
PFOS
PFOA
PFBS
0045-6535/$ - see front matter � 2008 Elsevier Ltd. A
doi:10.1016/j.chemosphere.2008.04.029
* Corresponding author. Tel.: +1 520 626 2896; fax
E-mail address: [email protected] (R. Sierr
Perfluorinated surfactants are emerging pollutants of increasing public health and environmental
concern due to recent reports of their world-wide distribution, environmental persistence and bioaccu-
mulation potential. Treatment methods for the removal of anionic perfluorochemical (PFC) surfactants
from industrial effluents are needed to minimize the environmental release of these pollutants. Removal
of PFC surfactants from aqueous solutions by sorption onto various types of granular activated carbon
was investigated. Three anionic PFC surfactants, i.e., perfluorooctane sulfonate (PFOS), perfluorooctanoic
acid (PFOA) and perfluorobutane sulfonate (PFBS), were evaluated for the ability to adsorb onto activated
carbon. Additionally, the sorptive capacity of zeolites and sludge for PFOS was compared to that of
granular activated carbon. Adsorption isotherms were determined at constant ionic strength in a pH
7.2 phosphate buffer at 30 �C. Sorption of PFOS onto activated carbon was stronger than PFOA and PFBS,
suggesting that the length of the fluorocarbon chain and the nature of the functional group influenced
sorption of the anionic surfactants. Among all adsorbents evaluated in this study, activated carbon
(Freundlich KF values = 36.7�60.9) showed the highest affinity for PFOS at low aqueous equilibrium
concentrations, followed by the hydrophobic, high-silica zeolite NaY (Si/Al 80, KF = 31.8), and anaerobic
sludge (KF = 0.95�1.85). Activated carbon also displayed a superior sorptive capacity at high soluble
concentrations of the surfactant (up to 80 mg l�1). These findings indicate that activated carbon adsorp-
tion is a promising treatment technique for the removal of PFOS from dilute aqueous streams.
� 2008 Elsevier Ltd. All rights reserved.
1. Introduction
Perfluorinated (PFC) surfactants are emerging pollutants that
have been used for the last 50 years in a wide variety of industrial
processes and consumer-based products, including polymer addi-
tives, lubricants, fire retardants and suppressants, pesticides, and
surfactants (Kissa, 2001). Quantitatively, pefluorooctane sulfonate
(PFOS, C8F17SO3H) and ...
Per- and Polyfluoroalkyl Substances (PFAS) Panel - Michael Honeycutt, Amber B...TWCA
The document provides information on a panel discussion at the 2019 TWCA Fall Conference on Per- and Polyfluoroalkyl Substances (PFAS). The panel will include three speakers: Michael Honeycutt of TCEQ discussing PFAS health effects and regulation; Jeffrey Wood of Baker Botts on PFAS regulatory, legislative, and litigation updates; and Amber Batson of CDM Smith on PFAS fate at utilities. The document provides background information on PFAS including uses, exposure, toxicity, and regulatory perspectives.
Toward a comprehensive global database of Per- and Polyfluoroalkyl Substance...OECD Environment
This document summarizes the creation of an updated, comprehensive list of per- and polyfluoroalkyl substances (PFASs) that may have been on the global market. Over 4,700 CAS numbers were identified from various sources and categorized. There are limitations due to information gaps and challenges in categorization. Opportunities for developing this list further include creating an online database that can be regularly updated, addressing knowledge gaps, and expanding the PFAS terminology through cooperation.
Eu actions to regulate Per- and Polyfluoroalkyl SubstancesOECD Environment
On Tuesday 25 February 2020, Eeva Leinala of the OECD Environment Directorate and Valentina Bertato of the DG Environment, European Commission presented the European Union's actions to regulate PFASs. It covered recent actions for restricting PFASs compounds and a strategy moving forward. This webinar is part of a series aiming to share information on issues related to PFASs and support a global transition towards safer alternatives.
This slideshow describes the forensic signatures of Per- and Polyfluoroalkyl Substances (PFAS) in surface water and groundwater based on literature data and contaminated fate & transport processes.
It includes slides presented by Andrew Cohen at the Emerging Contaminants Program Meeting, Environmental Business Council of New England, May 2, 2019.
Wellington Laboratories has been committed to providing high quality reference standards and exceptional customer service since its inception in 1980.
The primary source of Standards for EPA Methods 23, 513, 1613, 1668, 8280, 8290, European Method EN-1948 and World Health/EPA Standards, C13 and Native Dioxins, Furans, PCBs and Brominated Diphenyl Ethers, Brominated Dioxins and Furans, Methylated PCDDs and PCDFs, Fluorinated Compounds and more. Wellington Laboratories' offer a large range of native and mass-labelled per- and poly-fluorinated compounds.
PFAS (per- and polyfluoroalkyl
substances), known as “forever
chemicals” are found in everyday
objects. Food Packaging, paints,
cosmetics, wood lacquers, sealants ,
solar panels, fire fighting foams,
artificial grass and many more
seemingly innocent products.
Generally used to prevent corrosion
and make products waterproof and
stain-resistant they are present in our
everyday life. Unfortunately they do
not break down in our environment
and as a consequence are “forever
present”. Greyhound Chromatography provides a wide range of Chromatography related products for testing and analysis of PFAS and many other 'forever chemicals'.
This document summarizes a presentation on assessing the hazards of fluorinated alternatives to long-chain PFASs. It notes that industry has largely replaced long-chain PFASs with short-chain PFASs and perfluoro(poly)ether moieties. However, there is little information on many of the new alternatives. While short-chain PFASs have lower bioaccumulation than long-chain ones, they can still persist and contaminate drinking water aquifers for decades or centuries. The document concludes that a precautionary approach may be needed since all PFASs ultimately persist globally and contamination from them is poorly reversible, posing a potential planetary boundary threat.
Chemosphere 72 (2008) 1588–1593Contents lists available at S.docxchristinemaritza
Chemosphere 72 (2008) 1588–1593
Contents lists available at ScienceDirect
Chemosphere
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c h e m o s p h e r e
Removal of perfluorinated surfactants by sorption onto granular activated
carbon, zeolite and sludge
Valeria Ochoa-Herrera, Reyes Sierra-Alvarez *
Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ 85721-0011, USA
a r t i c l e i n f o a b s t r a c t
Article history:
Received 4 January 2008
Received in revised form 9 April 2008
Accepted 9 April 2008
Available online 3 June 2008
Keywords:
Adsorption
Biosorption
PFC
PFOS
PFOA
PFBS
0045-6535/$ - see front matter � 2008 Elsevier Ltd. A
doi:10.1016/j.chemosphere.2008.04.029
* Corresponding author. Tel.: +1 520 626 2896; fax
E-mail address: [email protected] (R. Sierr
Perfluorinated surfactants are emerging pollutants of increasing public health and environmental
concern due to recent reports of their world-wide distribution, environmental persistence and bioaccu-
mulation potential. Treatment methods for the removal of anionic perfluorochemical (PFC) surfactants
from industrial effluents are needed to minimize the environmental release of these pollutants. Removal
of PFC surfactants from aqueous solutions by sorption onto various types of granular activated carbon
was investigated. Three anionic PFC surfactants, i.e., perfluorooctane sulfonate (PFOS), perfluorooctanoic
acid (PFOA) and perfluorobutane sulfonate (PFBS), were evaluated for the ability to adsorb onto activated
carbon. Additionally, the sorptive capacity of zeolites and sludge for PFOS was compared to that of
granular activated carbon. Adsorption isotherms were determined at constant ionic strength in a pH
7.2 phosphate buffer at 30 �C. Sorption of PFOS onto activated carbon was stronger than PFOA and PFBS,
suggesting that the length of the fluorocarbon chain and the nature of the functional group influenced
sorption of the anionic surfactants. Among all adsorbents evaluated in this study, activated carbon
(Freundlich KF values = 36.7�60.9) showed the highest affinity for PFOS at low aqueous equilibrium
concentrations, followed by the hydrophobic, high-silica zeolite NaY (Si/Al 80, KF = 31.8), and anaerobic
sludge (KF = 0.95�1.85). Activated carbon also displayed a superior sorptive capacity at high soluble
concentrations of the surfactant (up to 80 mg l�1). These findings indicate that activated carbon adsorp-
tion is a promising treatment technique for the removal of PFOS from dilute aqueous streams.
� 2008 Elsevier Ltd. All rights reserved.
1. Introduction
Perfluorinated (PFC) surfactants are emerging pollutants that
have been used for the last 50 years in a wide variety of industrial
processes and consumer-based products, including polymer addi-
tives, lubricants, fire retardants and suppressants, pesticides, and
surfactants (Kissa, 2001). Quantitatively, pefluorooctane sulfonate
(PFOS, C8F17SO3H) and ...
Presentation on Overall trends of the replacements of long chain per- and pol...OECD Environment
On 19 May 2016, Eeva Leinala of the OECD Environment Directorate and Zhanyun Wang from ETH Zurich presented background information, an overview of alternatives and some initial lessons learned about the replacements of Long- Chain Per- and Polyfluoroalkyl Substances.
Shoji Nakayama: Worldwide trends in tracing PFASs in the environmentOECD Environment
On 11 June 2020, the OECD hosted a webinar on the latest developments in analytical and monitoring methods for PFASs. It is important to understand the levels and trends of PFASs in the global environment, biota and in products so as to take relevant measures to reduce environmental and human exposure.
The webinar featured the following speakers:
Introduction by Eeva Leinala, Principal Administrator, Environment Directorate, OECD
Shoji Nakayama, Centre for Health and Environmental Risk Research, National Institute for Environmental Studies, Japan presented work on worldwide trends in tracing PFAS in the environment;
Chris Impellitteri, EPA’s Office of Research and Development, United States presented an update on EPA’s Analytical Methods for PFAS;
Stefan Posner, Independent researcher, presented work on the development of CEN and ISO test methods for the analysis of PFAS in textile and leather.
The webinar video recording is available at: https://youtu.be/O9s4qvD9i_c
PFAS NOW HAS AN EXPIRY DATE: SMART SOLUTIONS FOR WATER INFRASTRUCTUREiQHub
This document discusses PFAS (per- and polyfluoroalkyl substances), their history, attributes, and technologies for their future removal. It provides background on PFAS, noting their widespread production peaked in the 1990s-2000s and there are now approximately 80 known PFAS compounds. It also summarizes health effects linked to PFAS exposure like various cancers, immune system problems, and pregnancy complications. The document then discusses the "forever" implications of PFAS due to their chemical structure, explaining they can persist in the environment and humans for decades. Finally, it evaluates various technology options for PFAS removal, including granular activated carbon, ion exchange, reverse osmosis, and newer options like adsorbent media and
Risk Reduction Initiatives for Per- and Polyfluoroalkyl substances in the Uni...OECD Environment
On 15 May 2019, Eeva Leinala of the OECD Environment Directorate, Sandi Moser of the Environment and Climate Change Canada, and Hannah Holsinger of the EPA presented the latest Risk Reduction Initiatives for Per- and Polyfluoroalkyl substances undertaken by Canada and the United States.
The presence of Per- and Polyfluorinated Alkyl Substances (PFAS) in drinking water is being thoroughly studied due to the persistence of these compounds in the environment and their potential health effects. However, there is limited knowledge about the occurrence of these chemicals in bottled water, despite the increasing concerns about PFAS in the food supply. This poster shows results from a fast and simple direct injection method similar to draft EPA method 8237, using the Shimadzu triple quad LCMS-8050 to analyze seven commercially available samples of bottled water for 24 PFAS.
Lessons Learned from PFAS in GroundwaterAntea Group
Presented by Jack Sheldon at the Groundwater Solutions: Innovating to Address Emerging Issues for Groundwater Resources Conference in Arlington, Virginia.
This document provides an introduction to per- and polyfluoroalkyl substances (PFAS). It discusses that PFAS are a group of man-made chemicals invented in the 1930s that are resistant to grease, water, stains and heat. While the health and environmental impacts of some PFAS are well understood, there are still major gaps in the scientific data. PFAS persist in the environment and are widely present in surface waters. Remediating PFAS contamination poses challenges due to their persistence in soils and complexity of sources. Understanding the conceptual site model is important for assessing risks and what remediation is possible.
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Current sample preparation techniques for PFAS analysis are laborious and not easily automated. In this study, supercritical fluid extraction (SFE) was evaluated as an alternative sample preparation technique for the extraction of eighteen PFAS compounds from fish tissue, as a preconcentration step prior to their analysis by LC-MS/MS.
This document provides an overview of different classes of diuretic drugs, including their mechanisms of action and sites of action in the nephron. It discusses loop diuretics such as furosemide, thiazide diuretics such as hydrochlorothiazide, potassium-sparing diuretics such as spironolactone, and carbonic anhydrase inhibitors such as acetazolamide. It also covers the synthesis of various diuretics, including furosemide and hydrochlorothiazide, and structure-activity relationships that determine diuretic activity. Side effects of furosemide like hypokalemia and ototoxicity are also mentioned.
This thesis examines organophosphate pesticide exposure in Australian agricultural workers through biological monitoring and risk assessment. A cross-sectional study assessed exposure among four groups: fruit and vegetable farmers, pilots and mixer/loaders, formulation plant staff, and a control group. Urine and blood samples were collected and questionnaires administered. Farmers had good pesticide knowledge but low personal protective equipment use. Urine testing found generally low pesticide metabolite levels in farmers, higher levels in formulators and pilots/mixer/loaders, and detectable levels in controls indicating environmental exposure. The urine test was a useful exposure indicator and may help industry risk assessment if biological exposure indices are established.
The PFOS Solution
Through our research, we found that our PristineRevival under-counter water systems already remove PFOS from drinking water! From the beginning, we wanted to give you the best drinking water that is properly mineralized, without all the contaminants or harmful acids.
Water Analysis Using LAMBDA UV/Visible Spectrophotometers: Ortho-Phosphate De...PerkinElmer, Inc.
In surface waters, phosphorus commonly exists in its phosphate form. A high concentration of phosphate in water is indicative of domestic waste, industrial effluent, and agricultural runoff which can lead to eutrophication. Eutrophication causes an increase in plant and algal growth, which decreases the dissolved oxygen in the water, often leaving the water uninhabitable to organisms. Most phosphates from these human sources are either polyphosphates or organically bound, which eventually degrade to ortho-phosphates (PO4
3−). In this application, the quantitative analysis of ortho-phosphate was performed using the LAMBDA 265™ UV/Vis spectrophotometer and CHEMetrics ortho-phosphate cell test kit.
Question 1 - 4 marks (750 words)Conceptual frameworks have ident.docxmakdul
Question 1 - 4 marks (750 words)
Conceptual frameworks have identified a number of qualitative criteria that financial information should possess if it is to be useful to decision making. The AASB framework Chapter 3 QC12-16 for example makes reference to ‘faithful representation’, with neutrality being one of the key components of ‘faithful representation’. Critically evaluate whether it is possible for financial information to ever be neutral and/or representationally faithful. In your discussion you should consider why standard setters might want to make reference to representational faithfulness within conceptual frameworks.
Question 3 - 4 marks (750 words)
The Conceptual Framework Chapter 1 OB2 states that "the objective of general purpose financial reporting is to provide financial information about the reporting entity that is useful to existing and potential investors, lenders and other creditors in making decisions about providing resources to the entity" Does the identification of these particular users have implications for the measurement basis chosen by the IASB? In your response you will need to consider whether fair values or historical costs will be more relevant to the users identified within the conceptual framework.
text book - Deegan, C. (2014). Financial accounting theory (4th ed.). McGraw-Hill: Sydney.
w a t e r r e s e a r c h 4 3 ( 2 0 0 9 ) 1 1 5 0 – 1 1 5 8
A v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / w a t r e s
Sorption of perfluorooctane sulfonate and perfluorooctanoate
on activated carbons and resin: Kinetic and isotherm study
Qiang Yua,b,c, Ruiqi Zhanga, Shubo Denga,b,c,*, Jun Huanga,b,c, Gang Yua,b,c
aDepartment of Environmental Science and Engineering, Tsinghua University, Beijing 100084, PR China
bPOPs Research Center, Tsinghua University, Beijing 100084, PR China
cState Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, PR China
a r t i c l e i n f o
Article history:
Received 5 August 2008
Received in revised form
30 November 2008
Accepted 1 December 2008
Published online 13 December 2008
Keywords:
PFOS
PFOA
Activated carbon
Anion-exchange resin
Sorption kinetics
Sorption isotherm
* Corresponding author. Department of En
Tel.: þ86 10 6279 2165; fax: þ86 10 6279 4006
E-mail address: [email protected]
0043-1354/$ – see front matter ª 2008 Elsevi
doi:10.1016/j.watres.2008.12.001
a b s t r a c t
Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) have increasingly attrac-
ted global concerns in recent years due to their global distribution, persistence, strong
bioaccumulation and potential toxicity. The feasibility of using powder activated carbon
(PAC), granular activated carbon (GAC) and anion-exchange resin (AI400) to remove PFOS
and PFOA from water was investigated with regard to their sorption kinetics and
isotherms ...
The presentation provides a brief background on phosphorus, introduces phosphates, gives examples of forms of phosphates. It further describes how to test for the forms of phosphates as well as how to regulate water phosphate level. It ends with some basic facts "Did you know".
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Kate Scow and colleagues assessed phosphorus cycling in agricultural soils using oxygen isotope analysis of phosphate. They took soil cores from organic and conventional crop rotation plots at Russell Ranch that received either organic or mineral fertilizer. Phosphate was extracted from soils using different methods and the oxygen isotopic composition was measured. Results showed higher phosphorus concentrations in the organic treatment soils. Isotopic signatures suggested more recycled phosphorus in the mineral treatment compared to the organic treatment. This study demonstrated the utility of oxygen isotopes of phosphate in distinguishing phosphorus sources and cycling pathways in agricultural soils under different management practices.
“Chemical and microbial treatment of toxic wastes from fertilizers industry”Omar Ali
Phosphate and fluoride are of commonly detected contaminants in the wastewater of fertilizer industries that produce nitro-phosphate. Chemical precipitation is the mainly responsible for remediation of TP and F-contaminated wastewater.
This document reports on a study that analyzed aflatoxin contamination in three chili varieties (Longi, Wonder hot, and Skyline 1) grown in Pakistan. Aflatoxins were detected in 60%, 67%, and 54% of samples from the three varieties, respectively. Concentrations ranged from 4.7 to 34.6 μg/kg in Longi, 1.0 to 14.3 μg/kg in Wonder hot, and 7.8 to 15.6 μg/kg in Skyline 1. Over half of the samples exceeded the European Union limit for AFB1 and total aflatoxins. Mean contamination was significantly lower in Wonder hot (5.8 μg/kg) than in Longi
Presentation on Overall trends of the replacements of long chain per- and pol...OECD Environment
On 19 May 2016, Eeva Leinala of the OECD Environment Directorate and Zhanyun Wang from ETH Zurich presented background information, an overview of alternatives and some initial lessons learned about the replacements of Long- Chain Per- and Polyfluoroalkyl Substances.
Shoji Nakayama: Worldwide trends in tracing PFASs in the environmentOECD Environment
On 11 June 2020, the OECD hosted a webinar on the latest developments in analytical and monitoring methods for PFASs. It is important to understand the levels and trends of PFASs in the global environment, biota and in products so as to take relevant measures to reduce environmental and human exposure.
The webinar featured the following speakers:
Introduction by Eeva Leinala, Principal Administrator, Environment Directorate, OECD
Shoji Nakayama, Centre for Health and Environmental Risk Research, National Institute for Environmental Studies, Japan presented work on worldwide trends in tracing PFAS in the environment;
Chris Impellitteri, EPA’s Office of Research and Development, United States presented an update on EPA’s Analytical Methods for PFAS;
Stefan Posner, Independent researcher, presented work on the development of CEN and ISO test methods for the analysis of PFAS in textile and leather.
The webinar video recording is available at: https://youtu.be/O9s4qvD9i_c
PFAS NOW HAS AN EXPIRY DATE: SMART SOLUTIONS FOR WATER INFRASTRUCTUREiQHub
This document discusses PFAS (per- and polyfluoroalkyl substances), their history, attributes, and technologies for their future removal. It provides background on PFAS, noting their widespread production peaked in the 1990s-2000s and there are now approximately 80 known PFAS compounds. It also summarizes health effects linked to PFAS exposure like various cancers, immune system problems, and pregnancy complications. The document then discusses the "forever" implications of PFAS due to their chemical structure, explaining they can persist in the environment and humans for decades. Finally, it evaluates various technology options for PFAS removal, including granular activated carbon, ion exchange, reverse osmosis, and newer options like adsorbent media and
Risk Reduction Initiatives for Per- and Polyfluoroalkyl substances in the Uni...OECD Environment
On 15 May 2019, Eeva Leinala of the OECD Environment Directorate, Sandi Moser of the Environment and Climate Change Canada, and Hannah Holsinger of the EPA presented the latest Risk Reduction Initiatives for Per- and Polyfluoroalkyl substances undertaken by Canada and the United States.
The presence of Per- and Polyfluorinated Alkyl Substances (PFAS) in drinking water is being thoroughly studied due to the persistence of these compounds in the environment and their potential health effects. However, there is limited knowledge about the occurrence of these chemicals in bottled water, despite the increasing concerns about PFAS in the food supply. This poster shows results from a fast and simple direct injection method similar to draft EPA method 8237, using the Shimadzu triple quad LCMS-8050 to analyze seven commercially available samples of bottled water for 24 PFAS.
Lessons Learned from PFAS in GroundwaterAntea Group
Presented by Jack Sheldon at the Groundwater Solutions: Innovating to Address Emerging Issues for Groundwater Resources Conference in Arlington, Virginia.
This document provides an introduction to per- and polyfluoroalkyl substances (PFAS). It discusses that PFAS are a group of man-made chemicals invented in the 1930s that are resistant to grease, water, stains and heat. While the health and environmental impacts of some PFAS are well understood, there are still major gaps in the scientific data. PFAS persist in the environment and are widely present in surface waters. Remediating PFAS contamination poses challenges due to their persistence in soils and complexity of sources. Understanding the conceptual site model is important for assessing risks and what remediation is possible.
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Current sample preparation techniques for PFAS analysis are laborious and not easily automated. In this study, supercritical fluid extraction (SFE) was evaluated as an alternative sample preparation technique for the extraction of eighteen PFAS compounds from fish tissue, as a preconcentration step prior to their analysis by LC-MS/MS.
This document provides an overview of different classes of diuretic drugs, including their mechanisms of action and sites of action in the nephron. It discusses loop diuretics such as furosemide, thiazide diuretics such as hydrochlorothiazide, potassium-sparing diuretics such as spironolactone, and carbonic anhydrase inhibitors such as acetazolamide. It also covers the synthesis of various diuretics, including furosemide and hydrochlorothiazide, and structure-activity relationships that determine diuretic activity. Side effects of furosemide like hypokalemia and ototoxicity are also mentioned.
This thesis examines organophosphate pesticide exposure in Australian agricultural workers through biological monitoring and risk assessment. A cross-sectional study assessed exposure among four groups: fruit and vegetable farmers, pilots and mixer/loaders, formulation plant staff, and a control group. Urine and blood samples were collected and questionnaires administered. Farmers had good pesticide knowledge but low personal protective equipment use. Urine testing found generally low pesticide metabolite levels in farmers, higher levels in formulators and pilots/mixer/loaders, and detectable levels in controls indicating environmental exposure. The urine test was a useful exposure indicator and may help industry risk assessment if biological exposure indices are established.
The PFOS Solution
Through our research, we found that our PristineRevival under-counter water systems already remove PFOS from drinking water! From the beginning, we wanted to give you the best drinking water that is properly mineralized, without all the contaminants or harmful acids.
Water Analysis Using LAMBDA UV/Visible Spectrophotometers: Ortho-Phosphate De...PerkinElmer, Inc.
In surface waters, phosphorus commonly exists in its phosphate form. A high concentration of phosphate in water is indicative of domestic waste, industrial effluent, and agricultural runoff which can lead to eutrophication. Eutrophication causes an increase in plant and algal growth, which decreases the dissolved oxygen in the water, often leaving the water uninhabitable to organisms. Most phosphates from these human sources are either polyphosphates or organically bound, which eventually degrade to ortho-phosphates (PO4
3−). In this application, the quantitative analysis of ortho-phosphate was performed using the LAMBDA 265™ UV/Vis spectrophotometer and CHEMetrics ortho-phosphate cell test kit.
Question 1 - 4 marks (750 words)Conceptual frameworks have ident.docxmakdul
Question 1 - 4 marks (750 words)
Conceptual frameworks have identified a number of qualitative criteria that financial information should possess if it is to be useful to decision making. The AASB framework Chapter 3 QC12-16 for example makes reference to ‘faithful representation’, with neutrality being one of the key components of ‘faithful representation’. Critically evaluate whether it is possible for financial information to ever be neutral and/or representationally faithful. In your discussion you should consider why standard setters might want to make reference to representational faithfulness within conceptual frameworks.
Question 3 - 4 marks (750 words)
The Conceptual Framework Chapter 1 OB2 states that "the objective of general purpose financial reporting is to provide financial information about the reporting entity that is useful to existing and potential investors, lenders and other creditors in making decisions about providing resources to the entity" Does the identification of these particular users have implications for the measurement basis chosen by the IASB? In your response you will need to consider whether fair values or historical costs will be more relevant to the users identified within the conceptual framework.
text book - Deegan, C. (2014). Financial accounting theory (4th ed.). McGraw-Hill: Sydney.
w a t e r r e s e a r c h 4 3 ( 2 0 0 9 ) 1 1 5 0 – 1 1 5 8
A v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / w a t r e s
Sorption of perfluorooctane sulfonate and perfluorooctanoate
on activated carbons and resin: Kinetic and isotherm study
Qiang Yua,b,c, Ruiqi Zhanga, Shubo Denga,b,c,*, Jun Huanga,b,c, Gang Yua,b,c
aDepartment of Environmental Science and Engineering, Tsinghua University, Beijing 100084, PR China
bPOPs Research Center, Tsinghua University, Beijing 100084, PR China
cState Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, PR China
a r t i c l e i n f o
Article history:
Received 5 August 2008
Received in revised form
30 November 2008
Accepted 1 December 2008
Published online 13 December 2008
Keywords:
PFOS
PFOA
Activated carbon
Anion-exchange resin
Sorption kinetics
Sorption isotherm
* Corresponding author. Department of En
Tel.: þ86 10 6279 2165; fax: þ86 10 6279 4006
E-mail address: [email protected]
0043-1354/$ – see front matter ª 2008 Elsevi
doi:10.1016/j.watres.2008.12.001
a b s t r a c t
Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) have increasingly attrac-
ted global concerns in recent years due to their global distribution, persistence, strong
bioaccumulation and potential toxicity. The feasibility of using powder activated carbon
(PAC), granular activated carbon (GAC) and anion-exchange resin (AI400) to remove PFOS
and PFOA from water was investigated with regard to their sorption kinetics and
isotherms ...
The presentation provides a brief background on phosphorus, introduces phosphates, gives examples of forms of phosphates. It further describes how to test for the forms of phosphates as well as how to regulate water phosphate level. It ends with some basic facts "Did you know".
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Kate Scow and colleagues assessed phosphorus cycling in agricultural soils using oxygen isotope analysis of phosphate. They took soil cores from organic and conventional crop rotation plots at Russell Ranch that received either organic or mineral fertilizer. Phosphate was extracted from soils using different methods and the oxygen isotopic composition was measured. Results showed higher phosphorus concentrations in the organic treatment soils. Isotopic signatures suggested more recycled phosphorus in the mineral treatment compared to the organic treatment. This study demonstrated the utility of oxygen isotopes of phosphate in distinguishing phosphorus sources and cycling pathways in agricultural soils under different management practices.
“Chemical and microbial treatment of toxic wastes from fertilizers industry”Omar Ali
Phosphate and fluoride are of commonly detected contaminants in the wastewater of fertilizer industries that produce nitro-phosphate. Chemical precipitation is the mainly responsible for remediation of TP and F-contaminated wastewater.
This document reports on a study that analyzed aflatoxin contamination in three chili varieties (Longi, Wonder hot, and Skyline 1) grown in Pakistan. Aflatoxins were detected in 60%, 67%, and 54% of samples from the three varieties, respectively. Concentrations ranged from 4.7 to 34.6 μg/kg in Longi, 1.0 to 14.3 μg/kg in Wonder hot, and 7.8 to 15.6 μg/kg in Skyline 1. Over half of the samples exceeded the European Union limit for AFB1 and total aflatoxins. Mean contamination was significantly lower in Wonder hot (5.8 μg/kg) than in Longi
Improving the viability of probiotics by encapsulation methods for developmen...Open Access Research Paper
The popularity of functional foods among scientists and common people has been increasing day by day. Awareness and modernization make the consumer think better regarding food and nutrition. Now a day’s individual knows very well about the relation between food consumption and disease prevalence. Humans have a diversity of microbes in the gut that together form the gut microflora. Probiotics are the health-promoting live microbial cells improve host health through gut and brain connection and fighting against harmful bacteria. Bifidobacterium and Lactobacillus are the two bacterial genera which are considered to be probiotic. These good bacteria are facing challenges of viability. There are so many factors such as sensitivity to heat, pH, acidity, osmotic effect, mechanical shear, chemical components, freezing and storage time as well which affects the viability of probiotics in the dairy food matrix as well as in the gut. Multiple efforts have been done in the past and ongoing in present for these beneficial microbial population stability until their destination in the gut. One of a useful technique known as microencapsulation makes the probiotic effective in the diversified conditions and maintain these microbe’s community to the optimum level for achieving targeted benefits. Dairy products are found to be an ideal vehicle for probiotic incorporation. It has been seen that the encapsulated microbial cells show higher viability than the free cells in different processing and storage conditions as well as against bile salts in the gut. They make the food functional when incorporated, without affecting the product sensory characteristics.
Evolving Lifecycles with High Resolution Site Characterization (HRSC) and 3-D...Joshua Orris
The incorporation of a 3DCSM and completion of HRSC provided a tool for enhanced, data-driven, decisions to support a change in remediation closure strategies. Currently, an approved pilot study has been obtained to shut-down the remediation systems (ISCO, P&T) and conduct a hydraulic study under non-pumping conditions. A separate micro-biological bench scale treatability study was competed that yielded positive results for an emerging innovative technology. As a result, a field pilot study has commenced with results expected in nine-twelve months. With the results of the hydraulic study, field pilot studies and an updated risk assessment leading site monitoring optimization cost lifecycle savings upwards of $15MM towards an alternatively evolved best available technology remediation closure strategy.
Optimizing Post Remediation Groundwater Performance with Enhanced Microbiolog...Joshua Orris
Results of geophysics and pneumatic injection pilot tests during 2003 – 2007 yielded significant positive results for injection delivery design and contaminant mass treatment, resulting in permanent shut-down of an existing groundwater Pump & Treat system.
Accessible source areas were subsequently removed (2011) by soil excavation and treated with the placement of Emulsified Vegetable Oil EVO and zero-valent iron ZVI to accelerate treatment of impacted groundwater in overburden and weathered fractured bedrock. Post pilot test and post remediation groundwater monitoring has included analyses of CVOCs, organic fatty acids, dissolved gases and QuantArray® -Chlor to quantify key microorganisms (e.g., Dehalococcoides, Dehalobacter, etc.) and functional genes (e.g., vinyl chloride reductase, methane monooxygenase, etc.) to assess potential for reductive dechlorination and aerobic cometabolism of CVOCs.
In 2022, the first commercial application of MetaArray™ was performed at the site. MetaArray™ utilizes statistical analysis, such as principal component analysis and multivariate analysis to provide evidence that reductive dechlorination is active or even that it is slowing. This creates actionable data allowing users to save money by making important site management decisions earlier.
The results of the MetaArray™ analysis’ support vector machine (SVM) identified groundwater monitoring wells with a 80% confidence that were characterized as either Limited for Reductive Decholorination or had a High Reductive Reduction Dechlorination potential. The results of MetaArray™ will be used to further optimize the site’s post remediation monitoring program for monitored natural attenuation.
Kinetic studies on malachite green dye adsorption from aqueous solutions by A...Open Access Research Paper
Water polluted by dyestuffs compounds is a global threat to health and the environment; accordingly, we prepared a green novel sorbent chemical and Physical system from an algae, chitosan and chitosan nanoparticle and impregnated with algae with chitosan nanocomposite for the sorption of Malachite green dye from water. The algae with chitosan nanocomposite by a simple method and used as a recyclable and effective adsorbent for the removal of malachite green dye from aqueous solutions. Algae, chitosan, chitosan nanoparticle and algae with chitosan nanocomposite were characterized using different physicochemical methods. The functional groups and chemical compounds found in algae, chitosan, chitosan algae, chitosan nanoparticle, and chitosan nanoparticle with algae were identified using FTIR, SEM, and TGADTA/DTG techniques. The optimal adsorption conditions, different dosages, pH and Temperature the amount of algae with chitosan nanocomposite were determined. At optimized conditions and the batch equilibrium studies more than 99% of the dye was removed. The adsorption process data matched well kinetics showed that the reaction order for dye varied with pseudo-first order and pseudo-second order. Furthermore, the maximum adsorption capacity of the algae with chitosan nanocomposite toward malachite green dye reached as high as 15.5mg/g, respectively. Finally, multiple times reusing of algae with chitosan nanocomposite and removing dye from a real wastewater has made it a promising and attractive option for further practical applications.
Kinetic studies on malachite green dye adsorption from aqueous solutions by A...
HawaiiPFASsRB-Oct-2020.pptx
1. Roger Brewer, PhD (roger.brewer@doh.hawaii.gov)
Hawai′i Department of Health
State Risk Assessor Association
(October 20, 2020)
Untangling the PFASs Web - Perspectives on
Fate, Risk and Screening Levels from Hawaii
1
2. PFASs in Hawaii
Maui Airport PFAS Plume
PFAS Makeup – Fire Training Area
PFAS Makeup – Downgradient Area
• Low risk (not drinking water);
• Potential discharge to shoreline;
• Two areas tested;
• One or two sources?
• Ok to only focus on PFOS- and PFOA-?
• Expanded action levels needed.
Draft!
Draft!
PFOS-
41%
PFHxS-
22%
PFHxA-
22%
PFBS-
10%
Other 5%
Relative Percent of Total PFASs
Downgradient
Area
Fire Training
Area
250’
? Downgradient
Area
PFHxA-
41%
PFBS-
35%
PFHxS-
20%
PFOS- 0.41% Other 3%
Relative Percent of Total PFASs
2
3. Outline
• Nature and use of PFASs (brief);
• Targeted PFASs (nomenclature, occurrence, lab analysis);
• Potential environmental concerns;
• Development of soil and groundwater action/screening
levels;
• Fire training site case study;
• Looming Issues:
• Leaching from soil (models vs lab tests);
• Wastewater, biosolids and uptake into food crops;
• Collection of representative sample data.
3
Risk Assessor: Someone who does precision guesswork based on
unreliable data provided by those of questionable knowledge.
See also Wizard, Magician.
(unknown - adapted from a T-Shirt)
4. Interim Soil and Water Environmental Action Levels (EALs)
for Perfluoroalkyl and Polyfluoroalkyl Substances (PFASs),
July 20, 2020 (public review draft, updated in Fall 2020):
https://health.hawaii.gov/heer/guidance/additional-guidance-
documents/
Evaluation of Environmental Hazards at Sites with
Contaminated Soil and Groundwater (EALs):
https://health.hawaii.gov/heer/guidance/ehe-and-eals/
ITRC 2020: Per- and Polyfluoroalkyl Substances (PFAS)
Washington Dept of Ecology (Draft Oct 2020): Per- and
Polyfluoroalkyl Substances Chemical Action Plan
References
4
HIDOH Recorded Webinars:
https://health.hawaii.gov/heer/guidance/heer-webinars/
5. • Used since 1940s;
• Water- and oil-resistant textiles and papers;
• Non-stick cookware;
• Fire suppression foams;
• Metal plating and etching fluids;
• Emerging awareness of toxicity in 1970s;
• Persistent in the environment and
difficult/expensive to treat.
Use of PFASs
5
7. Targeted PFASs:
Protonated (H+) Acids versus Anions
Huh???
ITRC 2020 PFAS Document:
“Most PFAAs are present in environmental and human matrices
in their anionic form.”
“Although laboratories may be reporting… the (protonated) acid
form of their name, they are actually measuring the anionic
form…”
“Physical and chemical properties (of protonated acid vs anion
forms) are different, and it is important to know which form is
(present in the environment)… when attempting to explain…
environmental behavior… through mathematical fate and
transport modeling (i.e., assessment of risk and development of
screening levels)”
Conflict Between Lab Data
and Assessment of Risk?
7
8. Risk
Assessment
Reporting by
Laboratory
Occurrence
in Nature
Toxicity
Studies
Why do labs report PFAS data as protonated acids?
• Laboratories process samples in a manner that converts any H+ acid
forms of compounds present to anion forms (methods can’t distinguish
protonated acid forms from anion forms);
• As a default, measured anion-based concentration of compounds
converted to equivalent protonated acid concentrations for final reporting
[Cacid = Canion x (MWacid/MWanion)];
• Because… USEPA lab SOPs list protonated (H+) acid forms (e.g.,
Method 533, Method 537.1, based on testing of industrial chemicals?);
• Inconsequential in terms of reported concentration (< +0.1%) but
important implications for accurate evaluation of fate and transport, risk
assessment and risk communication;
• “What is the concentration of perfuoro octane sulfonic acid in drinking
water?” “Zero!”
• Toxicity studies based on a mix of acid forms and anion forms.
8
9. • Present action levels in terms of anion forms of compounds (dominant
form in nature);
• Add a superscript "-" after the abbreviation to denote reference to
anion form;
• “PFOS” = Perfluoro octane sulfonic acid;
• “PFOS-” = Perfluoro octane sulfonate;
• Use physiochemical constants for anion forms to develop action levels -
affects solubility (higher), volatility (lower) and sorption (variable);
• Clarify that toxicity factors from studies based on doses of protonated
acid form of compound also applicable to anion form and vice versa
(difference in administerd dose inconsequential, < -0.1%).
First Lesson: Stick to the Anions…
(Planned Edits to HDOH July 2020 PFASs Guidance)
Risk
Assessment
Reporting by
Laboratory
Occurrence
in Nature
Toxicity
Studies 9
10. • Identify specific PFASs to target for investigations;
• Identify potential environmental concerns;
• Compile physiochemical constants and toxicity factors;
• Input into fate and transport and exposure risk models;
• Compile aquatic toxicity action levels (chronic and acute);
• Action levels optional for use (NOT promulgated
“standards”) - alternative, site-specific action levels can
be presented for review and approval.
Development of PFAS Soil and Groundwater
Action/Screening Levels
10
11. The “Big Nine” and Environmental Sources (minimum)
California
“Big Nine”
Fire Fighting
Training Areas
Landfill
Leachate
Wastewater
& Biosolids
PFBS- X x X
PFHxS- X x X
PFOS- X x X
PFPeA- ? X X
PFHxA- X X X
PFHpA- ? X X
PFOA- X X X
PFNA- x x ?
PFDA- ? ? ?
PFAS Precursors ? X X
PFOS- & PFOA-
• Typical focus of risk assessments and published action levels;
• Not the dominant PFAS at many sites;
• Action levels for other PFASs needed.
11
13. PFASs with Toxicity Factors
And Physiochemical Constants
HH Toxicity Factors (main) *Compounds (18)
USEPA (2014, 2016, 2018) PFBS, PFOS-, PFOA, HFPO-DA
Michigan (2019) PFHxS-, PFHxA, PFNA
Minnesota (2018) PFBA-
Texas (2016) PFOSA- (+RfCs for 8 PFASs)
Europe (RIVM 2018)
PFHpS, PFDS, PFPeA, PFHpA,
PFDA, PFUnA, PFDoDA,
PFTrDA, PFTeDA
*Physiochemical
Constants
USEPA, European Chemical
Agency, ITRC, etc.
*HDOH July 2020 EALs to be updated to reflect constants for anionic forms
*RfD based primarily on studies for protonated acid form of compound? 13
14. Aquatic Toxicity (acute and chronic)
(limited action levels available)
Reference Compounds (5)
Giesey et al (2010) PFBS-
Australia (2018) PFOS-, PFOA-
European Chemical
Agency (2018)
PFHxA-
UNDEP (2028)
Environment
PFHxS- (assumed = PFOS-)
• Several states compiling toxicity data (e.g., Washington);
• Similar “protonated acid vs anion” toxicity study issue;
• Drinking water action level used as temporary surrogate for if
aquatic toxicity if latter not available;
• Laboratory bioassay tests recommended if exceeded. 14
17. High Toxicity
High Mobility
Low Toxicity
Low Mobility
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CEL…
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
[CELLRANGE]
1.0E-06
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.00E+00 1.00E+02 1.00E+04 1.00E+06
PFASs Toxicity vs Mobility
High
Med
Low
RfD
(mg/kg-day)
Koc (cm3/g)
Increasing
Toxicity
Increasing Mobility
<1.0E-05
<1.0E-03
Low Toxicity
High Mobility
High Toxicity
Low Mobility
17
R
i
s
k
18. HFPO-DA- HFPO-DA- HFPO-DA-
PFHxA- PFHxA- PFHxA-
PFPeA- PFPeA- PFPeA-
PFBS- PFBS- PFBS-
PFHpA- PFHpA- PFHpA-
PFBA- PFBA- PFBA-
PFOA- PFOA-
PFHxS- PFHxS-
PFDA- PFDA-
PFNA- PFNA-
PFOS- PFOS-
PFHpS- PFHpS-
PFUnDA-
PFDS-
PFOSA-
PFDoDA-
PFTrDA-
PFTeDA-
Hypothetical PFASs Groundwater Plume Separation
(based on sorption and mobility)
Plume Leading Edge
Immediately
Downgradient
Source
Area
• High sorption PFASs concentrated in and near
source area;
• Low sorption PFASs at leading edge of plume;
• Very different PFAS compositions in source
area vs leading edge of the same plume.
Decreasing
Mobility
GW
18
19. PFASs in Hawaii
Maui Airport PFAS Plume
• Single groundwater plume?
• Most PFOS- trapped in source area?
• Downgradient area dominated by more
mobile PFASs (except PFHxS?);
• Fails aquatic toxicity action levels (install
more monitoring wells, check springs, etc.);
• DW action levels also exceeded.
Downgradient
Area
Fire Training
Area
250’
?
PFAS Makeup – Fire Training Area
PFAS Makeup – Downgradient Area
Draft!
Draft!
PFOS-
41%
PFHxS-
22%
PFHxA-
22%
PFBS-
10%
Other 5%
Relative Percent of Total PFASs
PFHxA-
41%
PFBS-
35%
PFHxS-
20%
PFOS- 0.41% Other 3%
Relative Percent of Total PFASs
19
20. PFOS-,
42%
PFHxS-,
46%
PFHxA-,
0.2%
PFBS-,
0.01%
Other,
9.7%
Relative PFAS Risk
Draft!
Draft!
PFAS Risk – Fire Training Area
PFAS Risk – Downgradient Area
20
PFAS Makeup – Fire Training Area
PFAS Makeup – Downgradient Area
Draft!
Draft!
PFOS-
41%
PFHxS-
22%
PFHxA-
22%
PFBS-
10%
Other 5%
Relative PFAS Makeup
PFHxA-
41%
PFBS-
35%
PFHxS-
20%
PFOS- 0.41% Other 3%
Relative PFASs Makeup
Twice as much PFOS- but
PFHxS- twice as toxic
PFHxA-,
0.9%
PFBS-, 0.1%
PFHxS-, 92%
PFOS-, 0.9%
Other, 5.9%
Relative PFAS Risk
Twice as much PFHxA-
but PFHxS- 200X as toxic
22. Leaching Models vs Laboratory Tests
Csoil = Cgw x [(6207 x H) + (0.166 x Koc)]
x
1. Concentration in groundwater
x
x
groundwater plume
x
2. Concentration in leachate
at groundwater interface
1m
• Specify targeted area and volume of soil for assessment (every drop?);
• SESOIL over predicts contaminant desorption and concentration in leachate;
• Synthetic Precipitation Leaching Procedure (SPLP) batch more accurately
estimates Kd and leaching hazards (see HDOH 2017)
• Better: “LEAF” Method 1314 soil column leaching tests.
3. Concentration in source leachate
22
4. Concentration in soil
(applies to specified volume)
23. PFASs Uptake Into Food Crops and Livestock Feed
Uptake from
Groundwater/Irrigation
Uptake from Soil
PFAS-contaminated
Crops?
PFAS-contaminated
soil (e.g., from biosolids)
PFAS-contaminated
water (e.g., leaching,
treated wastewater)
23
24. PFASs in Wastewater
Wastewater Source
*Total PFASs
(ng/L)
Example Source
Products
Domestic <100 (?)
Food packaging, dust,
household equipment
PFAS non-
intensive industry
100-1,000
Chrome plating,
hospital waste
PFAS intensive
industry
>1,000
Water proofing
agents, AFFF
Vo et al., 2019, Poly‐and perfluoroalkyl substances in water and wastewater: A
comprehensive review from sources to remediation: Journal of Water Process
Engineering 36 (2020) 101393
24
*Wastewater influent can be dominated by PFAS precursors;
increase in terminal anion forms in effluent due to oxidation.
25. Sludge and Biosolids Production:
• Approximately 75-100 tons of wastewater sludge (dry weight) generated
per one million people per day (after Univ Michigan, 2019);
• USA: 54% processed as “biosolids” and sold as soil amendment on 1%
of cropland (https://oecotextiles.blog/2015/08/25/are-biosolids-safe/);
• Significant increase in crop yield (nutrients, organic matter);
• Big problem if landfills and farmers start refusing to accept it…
10 tons (10 cubic yards)
PFASs in Wastewater Sludge & Biosolids
25
27. PFASs Distribution in Strawberry Plant
(lab study; after Higgins 2017)
Data from: Blaine et al., 2014b. ES&T. 48: 14361-14368.
1000
1500
2000
3000
2500
PFASs
(ng/g
dw
)
for
the
4
g/L
Applied
Dose
PFOS-
PFHxS-
PFBS-
PFNA-
PFOA-
PFHpA-
PFHxA-
PFPeA-
PFBA-
500
0
Root Shoot Fruit
PFBA-
PFPeA
PFHxA-
PFPeA-
PFHxA-
PFPeA-
PFHpA-
PFOA-
PFBS-
• Carboxylates > sulfonates;
• Longer-chain PFASs in shoot or root crops;
• Shorter-chain PFASs in fruit crops. 27
28. Soil and Groundwater/Irrigation Water
Plant Uptake Action Levels
Soil/Groundwater AL =
(Food Action Level/
Bioaccumulation Factor)
28
Plant:Soil BAF?
Plant:Water BAF?
Groundwater Action Level?
Soil Action Level?
Food Action Level?
BAF
Bioaccumulation Factor =
(Conc. in Plant/
Conc. in Soil or Water)
29. Dietary Action Levels
Default Pacific-Asian Diet – Child
(grams per day; HDOH 2010)
Cereals, 166g
Whole Milk,
158g
Fish, 57g
Fruits, 31g
Meat and
Products, 27g
Beverages
(excluding DW),
26g
Vegetables,
23g
Milk Products, 21g
Other,
54g
Total Daily Diet:
Food = 563 grams
Water = 0.78 liters
Soil: 200 mg
• Multiple ways to split up between food groups.
For example only!
29
30. Example PFASs Whole-Diet Action Levels
Compound
Target Average
Daily Dose
(BW=15kg,
RSC=0.8; HQ=0.5)
(ng/day)
Whole Diet
Action Level
(ng/kg)
PFBS-
120,000 213,333
PFHxS-
58 103
PFHpS-
60 107
PFOS-
120 213
PFDS-
60 107
PFBA-
22,800 40,533
PFPeA-
2,400 4,267
PFHxA-
12,000 21,333
PFHpA-
120 213
PFOA-
120 213
PFNA-
13 23
PFDA-
12 21
For example only!
30
Whole Diet AL=
Target ADDPFOS
-/
0.563 kg/day
Alternative: Assume
PFASs restricted to
a smaller number of
food groups
PFOS- Target ADD =
300 ng/day x 0.8 x 0.5
31. The Big Mystery - Soil and Water
PFASs Bioaccumulation Factors
Plant: Soil BAF?
Plant: Water BAF?
For example only!
• Published BAFs highly variable
within and between studies;
• Factors include soil type &
microbiome, plant species,
fertilizers, etc.;
• Also likely a sampling problem:
“Multi Increment” type sample
data required for both soil and
crops (not discrete!).
31
Groundwater Action Level?
Soil Action Level?
PFOS- Corn = 120 ng/kg
BAF
Bioaccumulation Factor =
(Conc. in Plant/
Conc. in Soil or Water)
32. 32
• Data for a discrete sample points and means for multiple points
are random within a (largely) unknown range.
Total Discrete Sample
Variability
Collection of Representative Sample Data
-Why Discrete Sample Data “Don’t Work”-
33. 33
Study Site
Range 95% UCL
(mg/kg) Range RSD
Site A
(arsenic)
403 to 776 34% to 67%
Site B
(lead)
201 to 439 20% to 86%
Site C
(PCBs)
9.4 to >1,000,000 124% to 315%
Implications for Risk Assessment: Mean Varies
Between Independent Sets of Discrete Sample Data
• Mean for single data set is random within an unknown range;
• Sample collection error in estimated mean can’t be quantified;
• Statistical analysis of single data set only evaluates the precision of the
statistical test employed to estimate a mean for the data set provided;
• Yields a false sense of data precision.
Replicate Data Sets (10 samples per set, 20 iterations)
34. Simple Solution: Decision Unit & Multi Increment Sample
Investigation Methods (HDOH 2016+)
x
x
x
x
x
x
x
x x
x
x
x
x
x
x
x
x
x x
x
x
x
x
X Sample Increment Points
• “What is the true (mean) concentration of the contaminant in the targeted
“Decision Unit” area and volume of soil (sediment, air, water, food, etc.)?”;
• For soil, collect a single, Multi Increment Sample by combining 20-40g
“increments” from 30 to 75 points (default = 50, minimum 1-2kg total mass);
• Sample carefully processed and subsampled at laboratory’
• Collect plant samples in similar manner;
• Collect replicate samples (triplicates) in some DUs to test total data precision.
35. Discrete Sample Data Reliability &
Decision Unit and Multi Increment Sample
Investigation Methods
35
Presentations and Training webinars (SRA July 2019):
http://eha-web.doh.hawaii.gov/eha-cma/Leaders/HEER/Webinar
Envirostat, Inc.: Chuck Ramsey (www.envirostat.org)
Four-day, detailed introduction to sampling theory and
Multi Increment Sample investigation methods (food,
drugs, soil, sediment, air, water, etc.)
HDOH, 2016, Technical Guidance Manual (Sections 3, 4 & 5): Hawai‘i
Department of Health, Office of Hazard Evaluation and Emergency
Response, http://www.hawaiidoh.org/
Brewer et al., 2017, A critical review of discrete soil sample reliability:
Journal of Soil and Sediment Contamination.
Part 1 - Field study Results: http://dx.doi.org/10.1080/15320383.2017.1244171
Part 2 – Implications: http://dx.doi.org/10.1080/15320383.2017.1244172
36. • Indoor Air:Subslab Vapor Attenuation
factors based on collection of a single,
1-6L vapor sample beneath each
building slab;
• Vapor sample from another point
would yield a different concentration;
• Database not scientifically defensible
for development of generic attenuation
factors;
• Can’t be “fixed” by statistical analysis;
• Useful but failed scientific study.
Frequency
Range of random noise/error
in subslab vapor sample data
Erroneous
95% UCL SSAF =0.03
Similar Problems With USEPA Vapor Intrusion Database
Brewer, R., Nagashima, J., Rigby, M., Schmidt, M. and O'Neill, H. (2014),
Estimation of Generic Subslab Attenuation Factors for Vapor Intrusion
Investigations. Groundwater Monitoring & Remediation, 34: 79–92.
http://onlinelibrary.wiley.com/doi/10.1111/gwmr.12086/full 36
Subslab AF =
Conc. Indoor Air
Conc. Soil Vapor
USEPA 2015
37. 37
Better: Collection of Representative Subslab Vapor Samples
(“Large Volume Purge” sampling methods)
LVP PCE Results (HDOH 2017):
Sample #1: 17,000 µg/m3
Sample #2: 36,000 µg/m3
Sample #3: 50,000 µg/m3
Sample #4: 51,000 µg/m3
Sample #5: 54,000 µg/m3
• Replicate five-day intrusion of vapors through a hypothetical vapor entry
point in slab (default = slab center);
• Continuous Summa sample drawn from each of five, 3,500 to 7,000 liter
purges from vapor point (default daily vapor entry rate);
• Hypothetical risk only - Still don’t know if sample data are representative of
vapors actually intruding the building (better but not reliable for SSAFs).
X
LVP Point
Reference: HDOH Technical Guidance Manual, Section 7 (Field study report and
recorded webinars available at: https://health.hawaii.gov/heer/guidance/heer-webinars/)
38. Summary
• EALs generated for 18 PFASs;
• Significantly expands other state & USEPA guidance;
• Able to more reliable screen PFAS sites for potential
environmental risks;
• Limited focus PFOS- and PFOA- could miss potential risks from
other PFASs present;
• Lingering concerns:
• Leaching from soil and impacts to groundwater;
• Uptake into edible plants from fields amended with biosolids
and or irrigated with treated wastewater;
• Updated PFASs action levels anticipated Fall 2020;
• Possible plant uptake studies in 2021 (coordinate with other states;
• Demonstration of both soil sample and plant sample data
representativeness critical.
USA:
Est. 2,000
trucks/day
38
Roger Brewer, PhD (roger.brewer@doh.hawaii.gov)
Hawai′i Department of Health