Progress 01/01/14 to 12/31/14
Outputs
Target Audience: The target audience reached by our efforts during this reporting period is the scientists and engineers evaluating the presence and potential risks associated with emerging contaminants present in reclaimed water, as well as the general public, Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? The project has provided graduate level training to two PhD students (Andrea Blaine and Katherine Hyland) and several non-thesis MS students. All have been exposed to the details of performing scientific research, including the writing and preparation of manuscripts. Dr. Blaine is now the Assistant Director of Water-Energy-Education, Science and Technology (WE2ST) at the Colorado School of Mines, while Dr. Hyalnd is now an Application Scientist with Sciex (a Mass Spectrometery instrument manufacturer). How have the results been disseminated to communities of interest? These data has been presented via several conferences and seminars. Higgins, C.P. Accumulation of Contaminants of Emerging Concern in Edible Crops. 51st Annual North American Chemical Residue Workshop. 20-23 July, 2014. St. Pete Beach, Florida (Invited Presentation). Higgins, C.P. Accumulation of Contaminants of Emerging Concern in Edible Crops. 97th Canadian Chemistry Conference and Exhibition, 1-5 June, 2014. Vancouver, British Columbia, Canada (Invited Presentation). Blaine, A.C., Hyland, K.C., Rich, C., and C.P. Higgins. "Accumulation of Contaminants of Emerging Concern in Edible Crops." Gordon Research Conference on Environmental Sciences: Water. 22-27 June, 2014. Plymouth, New Hampshire. (Poster) Hyland, K.C., Blaine, A.C., Rich, C., and C.P. Higgins. "Bioaccumulation of ionized and neutral emerging contaminants: Exposure of edible crops via solid and liquid effluent streams." 24th SETAC Europe Annual Meeting. Basel, Switzerland. 11-15 May, 2014. (Presentation). Higgins, C.P. Accumulation of Contaminants of Emerging Concern in Edible Crops. ABSciex Webinar, 30 January, 2014. Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hundal. L.S., Lau, C., Mills. M.A., Harris, K.M., and C.P. Higgins. "Perfluoroalkyl acid uptake and distribution in fresh food crops grown in biosolids-amended soils." 34th SETAC North America Annual Meeting. Nashville, Tennessee. 17-21 November, 2013. (Poster). Hyland, K.C., Blaine, A.C., Rich, C., Sedlacko, E.M. and C.P. Higgins. "Accumulation of Emerging Contaminants in Edible Crops Irrigated with Reclaimed Water." 34th SETAC North America Annual Meeting. Nashville, Tennessee. 17-21 November, 2013. (Presentation). Higgins, C.P. "Fate, Transport, and Bioaccumulation of Contaminants of Emerging Concern in Terrestrial Systems" Department of Agronomy, Purdue University. West Lafayette, Indiana. 30 September, 2013. (Presentation). Blaine, A.C., Rich, C., Hyland, K.C., Sedlacko, E.M., Dickenson, E.R.V. and C.P. Higgins. "Bioaccumulation of Perfluoroalkyl Acids in Edible Crops via Reclaimed Water." 28th Annual WateReuse Symposium. Denver, Colorado. 15-18 September, 2013. (Presentation). Hyland, K.C., Blaine, A.C., and C.P. Higgins. "Bioaccumulation of Emerging Contaminants in Edible Crops" 33rd SETAC North America Annual Meeting, 11-15 November, 2012. Long Beach, California. (Poster). Higgins, C.P. "Accumulation of Emerging Contaminants in Foodcrops from Reclaimed Water and Biosolids- Amended Soils" Association of Analytical Communities 126th Annual Meeting and Exposition, 30 September - 3 October, 2012. Las Vegas, Nevada. These data have also been included in a number of publications (published or in revision): Hyland, K.C., Blaine, A.C., Dickenson, E.R.V., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part One: Edible Strawberries and Lettuce Grown in Reclaimed Water. Environmental Toxicology and Chemistry, in revision. Hyland, K.C., Blaine, A.C., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part Two: Plant Distribution. Environmental Toxicology and Chemistry, in revision. Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hyland, K.C., Stushnoff, C., Dickenson, E.R.V and C.P. Higgins. 2014. Perfluoroalkyl acid uptake in lettuce (Lactuca sativa) and strawberry (Fragaria ananassa) irrigated with reclaimed water. Environmental Science and Technology, 48 (24): 14361- 14368. DOI:10.1021/es504150h Companion Studies (including field-validation of experimental greenhouse systems): Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hundal. L.S., Kumar, K., Lau, C., Mills. M.A., Harris, K.M., and C.P. Higgins*. 2014. Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils. Environmental Science and Technology, 48(14): 7858-7865. DOI:10.1021/es500016s Blaine, A.C., Rich, C.D., Kudryk, L.B., Hundal. L.S., Lau, C., Mills. M.A., Harris, K.M., and C.P. Higgins*. 2013. Uptake of perfluorinated alkyl substances into crops via land applied biosolids: Field and greenhouse studies. Environmental Science and Technology. 47(24): 14062-14069. DOI:10.1021/es403094q What do you plan to do during the next reporting period to accomplish the goals? This project is now complete, though revisions of submitted manuscripts is ongoing.
Impacts
What was accomplished under these goals?
Objective 1: Evaluate the dose-dependent bioaccumulation of selected CECs into edible food crops under controlled water reuse conditions. Controlled bioaccumulation greenhouse studies for both lettuce and strawberry were completed. These investigations were designed to elicit the concentration-dependent relationship between CEC concentrations in reclaimed water used for irrigation and plant uptake of CECs. The study consisted of 10 dosing conditions with five replicate plants per treatment. Doses included a tap water control, an ambient (background) of unfortified reclaimed water, and eight levels of increasing CEC concentration spiked above background. Concentrations of CECs in experimental plants were examined in separate plant compartments (roots, shoots, fruits) to discern how varying physicochemical properties of organic contaminants can affect partitioning within the plant. Results for many CECs indicate linear uptake with increasing concentration for many CECs. Of all CECs investigated, the short chain perfluorocarboxylates (PFCAs) and the chlorinated flame retardants TCEP and TCPP were shown to accumulate strongly and linearly with increasing concentration in edible fruit and leaf tissues, but less so in root tissues. Many other CECs also accumulated in a dose-dependent manner, but were generally less bioaccumulative than the chlorinated flame retardants and the short chain PFCAs. Objective 2: Determine the effects of cumulative water reuse loading rates and typical soil geochemical conditions on CEC bioaccumulation. To specifically test the impacts of organic carbon on CEC uptake, lettuce was grown in three soils with varying organic carbon content at a single CEC dose. The results indicate that perfluorochemicals uptake was generally dependent on the levels of organic carbon in the soil (decreasing uptake with increasing soil organic carbon), and this pattern was also apparent for some of the other CECs (i.e., TCEP and TCPP). However, the accumulation of other CECs, such as diphenhydramine and trimethroprim, was independent of the soil organic carbon content, indicating that soil organic carbon was not the primary factor controlling the bioavailability of these chemicals to the lettuce. Importantly, accumulation of perfluorochemicals from reclaimed water was significantly higher (in most cases) than from biosolids-amended soils, indicating that cumulative loading and aging effects could be significant. Objective 3: Examine the applicability of existing models and, if necessary, modify existing models to describe CEC bioaccumulation in plants. The patterns of accumulation of perfluorochemicals indicate that the traditional models for relating a chemical's hydrophobicity (i.e., Kow) to it's transpiration stream concentration factor (TSCF) are invalid. The newer paradigm, promoted by Dettenmaier et al. (ES&T 2009, 43: 324-329) appears to be more applicable to perfluorochemicals, as the more hydrophilic chemicals appear to be taken up and transported (within plants) to a greater extent. A conceptual model and framework for how to quantitatively predict uptake and distribution of perfluorochemicals is presented in one of the publications resulting from this work (Blaine et al., ES&T 2014b, 48:14361-14368). However, the traditional models of accumulation of organic chemicals in roots are not all wrong. Indeed, a strong correlation was observed for the other CECs examined between a chemical's pH-dependent Kow value and the root concentration factor (RCF), which is simply the ratio of the concentration in the root as compared to the concentration in the surrounding medium. The quantitative model and regression is included in one of the publications resulting from this work (Hyland et al., 2015b, ET&C, in revision). Objective 4: Validate the results from greenhouse and modeling studies through limited field monitoring and experimental studies. Though significant effort was expended to directly validate the results of this study with samples collected from commercial operations employing reclaimed water, the relatively low-levels of many of the targeted CECs limited our ability to complete this objective. However, as part of a companion effort to examine the bioaccumulation of perfluorochemicals in crops grown in biosolids-amended soils, the reclaimed water results from our perfluorochemical studies were validated in samples collected from field-trial plots as well as large-scale experimental plots employing biosolids-amended soils. These data, which were published in two papers from this companion study (Blaine et al., ES&T 2014a, 48: 7858-7865 and Blaine et al., ES&T 2013, 47:14062-14069) indicate that the results from our greenhouse experiments are representative of what one should expect under field conditions. Objective 5: Evaluate the results of these studies within the context of human exposure to CECs through the consumption of contaminated food crops. Our results indicate that at least for the pharmaceutical and personal care products examined, the presence of these chemicals in reclaimed water would not lead to a high level of exposure to these chemicals through consumption of contaminated food crops. The details of these calculations can be found in one of the publications resulting from this study (Hyland et al., 2015a, ET&C, in revision). However, in the case of perfluorochemicals, the results of our study (Blaine et al., ES&T 2014b, 48:14361-14368) indicate that depending on the levels of perfluorochemicals in reclaimed water, exposure via consumption of contaminated food crops could be significant. This is particularly important in light of the high variability of the levels of these compounds in wastewater effluent, which is likely a result of their use and released not only in the household but also from other light industrial activities. In short, if there is one class of chemicals to potentially be concerned about with respect human exposure to foodcrops irrigated with reclaimed water, perfluorochemicals warrant additional evaluation (particularly with respect to factors affecting the variable levels present in reclaimed water).
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hyland, K.C., Stushnoff, C., Dickenson, E.R.V and C.P. Higgins. 2014. Perfluoroalkyl acid uptake in lettuce (Lactuca sativa) and strawberry (Fragaria ananassa) irrigated with reclaimed water. Environmental Science and Technology, 48 (24): 14361- 14368. DOI:10.1021/es504150h
- Type:
Journal Articles
Status:
Under Review
Year Published:
2015
Citation:
Hyland, K.C., Blaine, A.C., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part Two: Plant Distribution. Environmental Toxicology and Chemistry, in revision.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2015
Citation:
Hyland, K.C., Blaine, A.C., Dickenson, E.R.V., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part One: Edible Strawberries and Lettuce Grown in Reclaimed Water. Environmental Toxicology and Chemistry, in revision.
|
Progress 01/01/11 to 12/31/14
Outputs
Target Audience: The target audience reached by our efforts during the project includes the scientists and engineers evaluating the presence and potential risks associated with emerging contaminants present in reclaimed water, as well as the general public. Specifically included are wastewater treatment plant operators and managers, and public officials responsible for evaluating the use of reclaimed water by utilities. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? The project has provided graduate level training to two PhD students and several non-thesis MS students. All have been exposed to the details of performing scientific research, including the writing and preparation of manuscripts. How have the results been disseminated to communities of interest? These data has been presented via several conferences and seminars. Higgins, C.P. Accumulation of Contaminants of Emerging Concern in Edible Crops. 51st Annual North American Chemical Residue Workshop. 20-23 July, 2014. St. Pete Beach, Florida (Invited Presentation). Higgins, C.P. Accumulation of Contaminants of Emerging Concern in Edible Crops. 97th Canadian Chemistry Conference and Exhibition, 1-5 June, 2014. Vancouver, British Columbia, Canada (Invited Presentation). Blaine, A.C., Hyland, K.C., Rich, C., and C.P. Higgins. "Accumulation of Contaminants of Emerging Concern in Edible Crops." Gordon Research Conference on Environmental Sciences: Water. 22-27 June, 2014. Plymouth, New Hampshire. (Poster) Hyland, K.C., Blaine, A.C., Rich, C., and C.P. Higgins. "Bioaccumulation of ionized and neutral emerging contaminants: Exposure of edible crops via solid and liquid effluent streams." 24th SETAC Europe Annual Meeting. Basel, Switzerland. 11-15 May, 2014. (Presentation). Higgins, C.P. Accumulation of Contaminants of Emerging Concern in Edible Crops. ABSciex Webinar, 30 January, 2014. Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hundal. L.S., Lau, C., Mills. M.A., Harris, K.M., and C.P. Higgins. "Perfluoroalkyl acid uptake and distribution in fresh food crops grown in biosolids-amended soils." 34th SETAC North America Annual Meeting. Nashville, Tennessee. 17-21 November, 2013. (Poster). Hyland, K.C., Blaine, A.C., Rich, C., Sedlacko, E.M. and C.P. Higgins. "Accumulation of Emerging Contaminants in Edible Crops Irrigated with Reclaimed Water." 34th SETAC North America Annual Meeting. Nashville, Tennessee. 17-21 November, 2013. (Presentation). Higgins, C.P. "Fate, Transport, and Bioaccumulation of Contaminants of Emerging Concern in Terrestrial Systems" Department of Agronomy, Purdue University. West Lafayette, Indiana. 30 September, 2013. (Presentation). Blaine, A.C., Rich, C., Hyland, K.C., Sedlacko, E.M., Dickenson, E.R.V. and C.P. Higgins. "Bioaccumulation of Perfluoroalkyl Acids in Edible Crops via Reclaimed Water." 28th Annual WateReuse Symposium. Denver, Colorado. 15-18 September, 2013. (Presentation). Hyland, K.C., Blaine, A.C., and C.P. Higgins. "Bioaccumulation of Emerging Contaminants in Edible Crops" 33rd SETAC North America Annual Meeting, 11-15 November, 2012. Long Beach, California. (Poster). Higgins, C.P. "Accumulation of Emerging Contaminants in Foodcrops from Reclaimed Water and Biosolids- Amended Soils" Association of Analytical Communities 126th Annual Meeting and Exposition, 30 September - 3 October, 2012. Las Vegas, Nevada. These data have also been included in a number of publications (published or in revision): Hyland, K.C., Blaine, A.C., Dickenson, E.R.V., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part One: Edible Strawberries and Lettuce Grown in Reclaimed Water. Environmental Toxicology and Chemistry, in revision. Hyland, K.C., Blaine, A.C., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part Two: Plant Distribution. Environmental Toxicology and Chemistry, in revision. Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hyland, K.C., Stushnoff, C., Dickenson, E.R.V and C.P. Higgins. 2014. Perfluoroalkyl acid uptake in lettuce (Lactuca sativa) and strawberry (Fragaria ananassa) irrigated with reclaimed water. Environmental Science and Technology, 48 (24): 14361- 14368.DOI:10.1021/es504150h Companion Studies (including field-validation of experimental greenhouse systems): Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hundal. L.S., Kumar, K., Lau, C., Mills. M.A., Harris, K.M., and C.P. Higgins*. 2014. Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils. Environmental Science and Technology, 48(14): 7858-7865. DOI:10.1021/es500016s Blaine, A.C., Rich, C.D., Kudryk, L.B., Hundal. L.S., Lau, C., Mills. M.A., Harris, K.M., and C.P. Higgins*. 2013. Uptake of perfluorinated alkyl substances into crops via land applied biosolids: Field and greenhouse studies. Environmental Science and Technology. 47(24): 14062-14069. DOI:10.1021/es403094q What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Objective 1: Evaluate the dose-dependent bioaccumulation of selected CECs into edible food crops under controlled water reuse conditions. Controlled bioaccumulation greenhouse studies for both lettuce and strawberry were completed. These investigations were designed to elicit the concentration-dependent relationship between CEC concentrations in reclaimed water used for irrigation and plant uptake of CECs. The study consisted of 10 dosing conditions with five replicate plants per treatment. Doses included a tap water control, an ambient (background) of unfortified reclaimed water, and eight levels of increasing CEC concentration spiked above background. Concentrations of CECs in experimental plants were examined in separate plant compartments (roots, shoots, fruits) to discern how varying physicochemical properties of organic contaminants can affect partitioning within the plant. Results for many CECs indicate linear uptake with increasing concentration for many CECs. Of all CECs investigated, the short chain perfluorocarboxylates (PFCAs) and the chlorinated flame retardants TCEP and TCPP were shown to accumulate strongly and linearly with increasing concentration in edible fruit and leaf tissues, but less so in root tissues. Many other CECs also accumulated in a dose-dependent manner, but were generally less bioaccumulative than the chlorinated flame retardants and the short chain PFCAs. Objective 2: Determine the effects of cumulative water reuse loading rates and typical soil geochemical conditions on CEC bioaccumulation. To specifically test the impacts of organic carbon on CEC uptake, lettuce was grown in three soils with varying organic carbon content at a single CEC dose. The results indicate that perfluorochemicals uptake was generally dependent on the levels of organic carbon in the soil (decreasing uptake with increasing soil organic carbon), and this pattern was also apparent for some of the other CECs (i.e., TCEP and TCPP). However, the accumulation of other CECs, such as diphenhydramine and trimethroprim, was independent of the soil organic carbon content, indicating that soil organic carbon was not the primary factor controlling the bioavailability of these chemicals to the lettuce. Importantly, accumulation of perfluorochemicals from reclaimed water was significantly higher (in most cases) than from biosolids-amended soils, indicating that cumulative loading and aging effects could be significant. Objective 3: Examine the applicability of existing models and, if necessary, modify existing models to describe CEC bioaccumulation in plants. The patterns of accumulation of perfluorochemicals indicate that the traditional models for relating a chemical's hydrophobicity (i.e., Kow) to it's transpiration stream concentration factor (TSCF) are invalid. The newer paradigm, promoted by Dettenmaier et al. (ES&T 2009, 43: 324-329) appears to be more applicable to perfluorochemicals, as the more hydrophilic chemicals appear to be taken up and transported (within plants) to a greater extent. A conceptual model and framework for how to quantitatively predict uptake and distribution of perfluorochemicals is presented in one of the publications resulting from this work (Blaine et al., ES&T 2014b, 48:14361-14368). However, the traditional models of accumulation of organic chemicals in roots are not all wrong. Indeed, a strong correlation was observed for the other CECs examined between a chemical's pH-dependent Kow value and the root concentration factor (RCF), which is simply the ratio of the concentration in the root as compared to the concentration in the surrounding medium. The quantitative model and regression is included in one of the publications resulting from this work (Hyland et al., 2015b, ET&C, in revision). Objective 4: Validate the results from greenhouse and modeling studies through limited field monitoring and experimental studies. Though significant effort was expended to directly validate the results of this study with samples collected from commercial operations employing reclaimed water, the relatively low-levels of many of the targeted CECs limited our ability to complete this objective. However, as part of a companion effort to examine the bioaccumulation of perfluorochemicals in crops grown in biosolids-amended soils, the reclaimed water results from our perfluorochemical studies were validated in samples collected from field-trial plots as well as large-scale experimental plots employing biosolids-amended soils. These data, which were published in two papers from this companion study (Blaine et al., ES&T 2014a, 48: 7858-7865 and Blaine et al., ES&T 2013, 47:14062-14069) indicate that the results from our greenhouse experiments are representative of what one should expect under field conditions. Objective 5: Evaluate the results of these studies within the context of human exposure to CECs through the consumption of contaminated food crops. Our results indicate that at least for the pharmaceutical and personal care products examined, the presence of these chemicals in reclaimed water would not lead to a high level of exposure to these chemicals through consumption of contaminated food crops. The details of these calculations can be found in one of the publications resulting from this study (Hyland et al., 2015a, ET&C, in revision). However, in the case of perfluorochemicals, the results of our study (Blaine et al., ES&T 2014b, 48:14361-14368) indicate that depending on the levels of perfluorochemicals in reclaimed water, exposure via consumption of contaminated food crops could be significant. This is particularly important in light of the high variability of the levels of these compounds in wastewater effluent, which is likely a result of their use and released not only in the household but also from other light industrial activities. In short, if there is one class of chemicals to potentially be concerned about with respect human exposure to foodcrops irrigated with reclaimed water, perfluorochemicals warrant additional evaluation (particularly with respect to factors affecting the variable levels present in reclaimed water).
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hyland, K.C., Stushnoff, C., Dickenson, E.R.V and C.P. Higgins. 2014. Perfluoroalkyl acid uptake in lettuce (Lactuca sativa) and strawberry (Fragaria ananassa) irrigated with reclaimed water. Environmental Science and Technology, 48 (24): 14361- 14368. DOI:10.1021/es504150h
- Type:
Journal Articles
Status:
Under Review
Year Published:
2015
Citation:
Hyland, K.C., Blaine, A.C., Dickenson, E.R.V., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part One: Edible Strawberries and Lettuce Grown in Reclaimed Water. Environmental Toxicology and Chemistry, in revision.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2015
Citation:
Hyland, K.C., Blaine, A.C., and C.P. Higgins. Accumulation of Contaminants of Emerging Concern in Food Crops, Part Two: Plant Distribution. Environmental Toxicology and Chemistry, in revision.
|
Progress 01/01/13 to 12/31/13
Outputs
Target Audience: The target audiences reached during 2013 were primarily the broader scientifc community through presentations at scientific meetings (i.e., the North American Socity of Environmental Toxicology and Chemistry Annual Meeting) as well as the WaterReuse community through a presentation at the Annual WaterReuse Symposium. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? The project has provided graduate level training to two PhD students and several non-thesis MS students. All have been exposed to the details of performing scientific research, including the writing and preparation of manuscripts. How have the results been disseminated to communities of interest? Preliminary data has been presented via several conferences and seminars: Higgins, C.P. Accumulation of Contaminants of Emerging Concern in Edible Crops. ABSciex Webinar, 30 January, 2014. Blaine, A.C., Rich, C.D., Sedlacko, E.M., Hundal. L.S., Lau, C., Mills. M.A., Harris, K.M., and C.P. Higgins. “Perfluoroalkyl acid uptake and distribution in fresh food crops grown in biosolids-amended soils.” 34th SETAC North America Annual Meeting. Nashville, Tennessee. 17-21 November, 2013. (Poster). Hyland, K.C., Blaine, A.C., Rich, C., Sedlacko, E.M. and C.P. Higgins. “Accumulation of Emerging Contaminants in Edible Crops Irrigated with Reclaimed Water.” 34th SETAC North America Annual Meeting. Nashville, Tennessee. 17-21 November, 2013. (Presentation). Higgins, C.P. “Fate, Transport, and Bioaccumulation of Contaminants of Emerging Concern in Terrestrial Systems” Department of Agronomy, Purdue University. West Lafayette, Indiana. 30 September, 2013. (Presentation). Blaine, A.C., Rich, C., Hyland, K.C., Sedlacko, E.M., Dickenson, E.R.V. and C.P. Higgins. “Bioaccumulation of Perfluoroalkyl Acids in Edible Crops via Reclaimed Water.” 28th Annual WateReuse Symposium. Denver, Colorado. 15-18 September, 2013. (Presentation). Hyland, K.C., Blaine, A.C., and C.P. Higgins. “Bioaccumulation of Emerging Contaminants in Edible Crops” 33rd SETAC North America Annual Meeting, 11-15 November, 2012. Long Beach, California. (Poster). Higgins, C.P. “Accumulation of Emerging Contaminants in Foodcrops from Reclaimed Water and Biosolids- Amended Soils” Association of Analytical Communities 126th Annual Meeting and Exposition, 30 September – 3 October, 2012. Las Vegas, Nevada. What do you plan to do during the next reporting period to accomplish the goals? · Complete analysis of plant tissues from both greenhouse and field studies. · Assess the applicability of current plant uptake models to data from this study. · Frame the data in the context of human exposure. · Submit results via three journal submissions.
Impacts
What was accomplished under these goals?
Objective 1: Evaluate the dose-dependent bioaccumulation of selected CECs into edible food crops under controlled water reuse conditions. Controlled bioaccumulation greenhouse studies for both lettuce and strawberry have been completed. These investigations were designed to elicit the dose-dependent relationship between CEC concentrations in reclaimed water used for irrigation and plant uptake of CECs. The study consisted of 10 dosing conditions with five replicate plants per treatment. Doses included a tap water control, an ambient (background) of unfortified reclaimed water, and eight levels of increasing CEC concentration spiked above background. Concentrations of CECs in experimental plants were examined in separate plant compartments (roots, shoots, fruits) to discern how varying physicochemical properties of organic contaminants can affect partitioning within the plant. All plant compartments have been harvested, extracted, and analyzed for PFAS, and approximately 80% of tissue samples are completed for non-PFAS CECs. Results for PFAS uptake indicate a linear-dose response in both the lettuce and strawberry for all analytes with the exception of the long-chain PFAS analytes in the strawberry fruit. The results for the pharmaceuticals and other CECs are taking shape but suggest distinct differences in the ability of individual plant compartments to accumulate target contaminants, in particular some ionized species such as trimethoprim, diphenhydramine, and amitriptyline. Chlorinated flame retardants TCEP and TCPP were shown to accumulate strongly and linearly with dose in edible fruit and leaf tissues, but less so in root tissues. Further analysis is ongoing to attempt to interpret the significance of these results. The successful completion of method development and validation represented a significant achievement to the project. Identification and optimization of extraction and analysis protocols and procedures ensures that data resulting from subsequent experiments intended to increase knowledge and understanding of CEC uptake in plants are accurate and reliable. Successful completion of the experimental phase of this project marked a critical milestone in this project; current emphasis is on the preparation of results. Objective 2: Determine the effects of cumulative water reuse loading rates and typical soil geochemical conditions on CEC bioaccumulation. To specifically test the impacts of organic carbon on CEC uptake, lettuce was grown in three soils with varying organic carbon content at a single CEC dose. The results for the PFAS uptake indicate that the lettuce grown in soil with the highest organic carbon content had the lowest bioaccumulation of PFASs. Results for the other CECs are still being analyzed. Successful completion of the experimental phase of this project marked a critical milestone in this project; current emphasis is on the preparation of results. Objective 3: Examine the applicability of existing models and, if necessary, modify existing models to describe CEC bioaccumulation in plants. The results of this study are still being assessed in the context of applicable existing models. Objective 4: Validate the results from greenhouse and modeling studies through limited field monitoring and experimental studies. To date, 100% of the field-scale monitoring samples have been analyzed for PFAS analytes and approximately 20% of the field collected samples have been analyzed for non-PFAS analytes. The results, while incomplete and not yet analyzed for statistical significance, show that in general a few PFAS analytes are found at trace levels, and non-PFAS CECs are not found at detectable levels in edible portions of strawberry and lettuce plants that have been watered with either well water or reclaimed water. The processing of these field samples, including extraction and analysis, is ongoing. Objective 5: Evaluate the results of these studies within the context of human exposure to CECs through the consumption of contaminated food crops. The results of this study are still being assessed in the context of human exposure.
Publications
|
Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Task 1: Analytical Method Validation Since the last report, methods for extraction and analysis of both perfluoroalkyl substances (PFASs) and non-PFAS contaminants of emerging concern (CECs) have been greatly refined. The PFAS analyte suite represents one analyte group, and the non-PFAS CECs are divided into two groups based on analytical methods required to measure these chemicals in environmental samples. Extraction, sample clean up, and analysis protocols are now in place for quantitation of all three groups of CECs in water, soil, and multiple types of plant tissues. These have been implemented in the quantitation of CECs in samples derived from initial greenhouse and field studies with success. Task 2: Field Scale Monitoring To date, 100% of the field collected samples have been analyzed for PFAS analytes and approximately 20% of the field collected samples have been analyzed for non-PFAS analytes. The results, while incomplete and not yet analyzed for statistical significance, show that in general a few PFAS analytes are found at trace levels, and non-PFAS CECs are not found at detectable levels in edible portions of strawberry and lettuce plants that have been watered with either well water or reclaimed water. The processing of these field samples, including extraction and analysis, is ongoing. Task 3: Greenhouse Bioaccumulation Studies Controlled bioaccumulation greenhouse studies are intended to elicit a dose-dependent relationship between CEC concentrations in reclaimed water used for irrigation and plant uptake of CECs. An initial "range- finding" pilot study was completed which examined four CEC dosing levels in strawberries and lettuce. The objective of this range-finding study was to refine the growing techniques and operational conditions that would be best suited to the overall project objective, as well as to identify those CECs that can be taken up into plants and appropriate dosing concentrations for a full-scale dose-dependence experiment. This initial pilot study was completed and the majority of the samples have been analyzed for all target analytes. The data collected thus far have been treated as preliminary, but useful in informing the experimental design of the subsequent study. The full study to thoroughly examine the dose-dependence of plant uptake of CECs has been initiated for strawberry plants. The study consists of 10 dosing conditions with five replicate plants per treatment. Doses include a tap water control, an ambient (background) of unfortified reclaimed water, and eight levels of increasing CEC concentration spiked above background. The experiment will also be conducted with lettuce plants starting in April 2013. The concentrations of CECs in the experimental plants will be examined in separate plant tissues, in order to discern how varying physicochemical properties of organic contaminants will lead to partitioning in tissues of different compositions (water content, lipid content) including edible and non-edible portions. This study has been fully designed and planned and is currently underway. Results for this portion of the overall project are expected to be realized by summer 2013. PARTICIPANTS: Christopher P. Higgins, PD, Colorado School of Mines Eric R.V. Dickenson, co-PD, Southern Nevada Water Authority George OConnor, co-PD, University of Florida Cecil Stushnoff, Colorado State University Andrea Blaine, Colorado School of Mines Katherine Hyland, Colorado School of Mines Courtney Rich, Colorado School of Mines Evan Gray, Colorado School of Mines Erin Sedlacko, Colorado School of Mines Lisa Kudryck, Colorado School of Mines TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The successful completion of method development and validation represented a significant achievement to the project. Identification and optimization of extraction and analysis protocols and procedures ensures that data resulting from subsequent experiments intended to increase knowledge and understanding of CEC uptake in plants will be accurate and reliable. Additionally, the completion of the pilot level experiment contributed greatly to the current knowledge. Several chemicals of interest were identified to be closely examined in future studies, as well and some chemical trends have begun to emerge which may prove to be interesting, relevant, and important to the collective scientific understanding. Additionally, all students involved in the project have gained significant experience in designing and executing complex greenhouse experiments including experimental design, set up, growing procedures, dosing with spiked reclaimed water, sample collection and preservation, and finally tissue extraction and analysis. The results achieved through these efforts and experiences will be reflected in future publications, with at least two journal submissions being projected for 2013.
Publications
- No publications reported this period
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Progress 01/01/11 to 12/31/11
Outputs
OUTPUTS: Task 1: Analytical Method Validation: Significant progress was made for the development and validation of analytical methods for measuring the selected CECs in soil, water, and plant materials, though they have yet to be finalized. Separate methods are used for the various matrices, water, soil, and plant, as well as for the perfluorinated chemicals(PFCs) versus non PFCs. For PFCs, the analytical method in both the aqueous and soil matrices has been verified. For plant analysis, samples are extracted similarly to soils. Ongoing investigations are aimed at improving surrogate recoveries for the plant analysis method to ensure valid data. Development of analytical methods for quantitation of non-PFC CECs also progressed substantially. is also in progress. This process began by first narrowing down the extensive list of potential organic contaminants to a set of analytes which are relevant and can be relatively easily analyzed. As with PFCs, a quantitative method is already validated and in use for analysis of aqueous samples, and the current work has been focused on methods for extraction, clean- up, and analysis of plant tissue and soil matrices. For the plant tissue and soils, various extraction methods have been explored using an Accelerated Solvent Extraction system. Optimization of solvent combinations and extraction conditions is ongoing, as is comparison of different sample clean- up methods for plant tissues intended to alleviate problems with background matrix interference and suppression experienced during quantitative analysis. Task 2: Field Scale Monitoring: Field sampling of lettuce and strawberries from the field-site took place in July of 2011. Produce samples were collected in a manner which was intended to best imitate harvesting for commercial sale. Additionally, each produce sample was collected alongside a soil sample from the plant's immediate vicinity. Strict sampling protocols were employed to avoid contamination of samples with target analytes. These preventative steps were intended to ensure that quantitative analysis of CECs on the collected plant tissues will solely represent the exposure which occurred in the field growing conditions. All samples were stored on ice for shipment to CSM. Upon arrival, all samples were stored frozen to await extraction and analysis. Task 3: Greenhouse Bioaccumulation Studies: Controlled bioaccumulation greenhouse studies are currently beginning at CSM using reclaimed water from the Mines Park pilot-scale Sequencing Batch/Membrane Bioreactor (MBR) test site which provides a steady and realistic source of reclaimed water. Using non-USDA funds, renovations at the MBR site over the past year have resulted in a brand new laboratory space along with a small-scale greenhouse (450 sq feet) constructed of polycarbonate sheeting and controlled by a Wadsworth system. The greenhouse has been outfitted with a new fan and pad cooling system, a natural gas-forced air heater, a lighting system with both metal halide and high-pressure sodium bulbs, and new benching. A complete manual detailing experimental protocols for all phases of the greenhouse experiments planned in the proposal has been drafted. PARTICIPANTS: Project Director (PD): Dr. Chris Higgins, Colorado School Of Mines CO-PD: Dr. Jorg Drewes, Colorado School Of Mines CO-PD: Dr. Eric Dickenson, Colorado School Of Mines CO-PD: Dr. George O'Connor, University Of Florida CO-PD: Dr. James Crook, Environmental Engineering Consultant Consultant: Dr. Cecil Stushnoff, Colorado State University Students at Colorado School of Mines: Katherine Hyland, PhD Student Andrea Blaine, PhD Student Erin Sedlacko, MS student Lisa Kudryck, MS student Courtney Rich, undergraduate student Partners: a wastewater treatment plant in coastal california (including several members of their staff) that wishes to remain anonymous. The various farmers involved also wish to remain anonymous at the present time. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Significant changes in knowledge were realized during the first year by both project participants and engaged stakeholders. This knowledge resulted from the development and validation of experimental and analysis protocols by the various graduate and undergraduate students involved in the research. In particular, the complexities associated with the analysis of CECs in plant tissue led to considerable gains in unit process understanding by the students involved in the research. Second, the development and evaluation of experimental protocols both with respect to the field component of the study and the greenhouse component led to substantial changes in knowledge among all project participants. This knowledge developed through the study design, particularly with respect to how one can mimic reclaimed water conditions in a greenhouse, will be a significant contribution to the scientific literature when included in future publications. Lastly, there was a significant change in knowledge among a limited groups of stakeholders during the preparation for and conduction of the field sampling campaign: an understanding of the potential issues surrounding CECs in reclaimed water was necessary to get buy-in both from the water providers and the farmers using the reclaimed water for their produce. There was also a significant two-way exchange of information with this group: project participants, namely students, learned quite a bit from the exchanges with the farmers and water utility personnel.
Publications
- No publications reported this period
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