Summaries Published in the April 2020 Issue
Alison Gamble, Shared Value Solutions, Ltd.
Indigenous communities across the globe have developed protocols that guide the acquisition of knowledge in ways that are compatible with their understanding of natural laws. However, “Western” approaches to scientific inquiry do not always align with these local protocols. This can result in divergent perspectives on environmental problems and solutions, which often leads to decision making that does not advance the goals of Indigenous peoples with respect to their lands. This session, supported by the Indigenous Knowledge and Values Interest Group, explored principles, practices and examples of collaboration between Indigenous Knowledge and “Western” approaches to scientific inquiry. Examples of constructive relationships between Indigenous communities and scientists trained in Western science were shared with an audience of approximately 92 people, highlighting how co-development of methods and meaningful collaboration can enhance investigations, understanding of environmental issues and decision making.
The session included both Indigenous and non-Indigenous presenters from government, academia and industry across the globe, followed by a facilitated discussion where session attendees were encouraged to share their experiences (both successes and challenges) in projects that promote collaboration between Indigenous Knowledge and Western science.
The key points from the seven session presentations included:
- Dan Kusnierz, Penobscot Indian Nation, presented on river restoration efforts that have resulted in the abundant return of several fish species to the waters where Penobscot tribal members fish for sustenance. The return of these species has restored an important part of the tribe’s traditional diet, which has resulted in collaborative work between the US Environmental Protection Agency (US EPA), Penobscot Nation and the Agency for Toxic Substances and Disease Registry to determine the safety of both human and wildlife consumption of these fish, which are impacted by unsafe levels of various contaminants.
- A case study exploring a successful collaborative approach to stream restoration on Georgina Island was presented by Kerry Ann Charles, Chippewas of Georgina Island First Nation. In the presented case study, Charles highlighted how the Indigenous Knowledge of the Chippewas of Georgina Island formed the basis of identifying how terrestrial activities had altered the natural function of stream and wetland riparian areas, and for determining the best approach to stream restoration for the prevention of ongoing flooding in the community.
- James Ataria, Cawthron Institute, presented on the challenges and critical issues that the Maori have faced when engaging in knowledge-sharing efforts between Indigenous and Western science. The presentation provided a historical context to help consider and identify the requirements for meaningful and respectful consideration of Maori knowledge within ecotoxicological and natural resource management projects.
- Gwyneth MacMillan, University of Montreal, presented in a captivating, unconventional way by using a short documentary film to highlight a community-based environmental monitoring program in Canada’s North. The film showcased how local Inuit Knowledge and scientific knowledge complement each other in the operation of a camp that monitors the important issues of water quality, edible marine and freshwater resources, and contaminants in country food within a rapidly changing Arctic ecosystem.
- Anti-colonial, community-based research methods for environmental science was presented by Max Liboiron, Memorial University of Newfoundland. Using a case study of how an Indigenous-led marine plastic pollution laboratory conducts research in Nunatsiavut, Liboiron demonstrated how enacting Indigenous values and perspectives at every stage of research (including instrument design, how samples are collected and with whom, community peer review, sampling techniques, and animal respect protocols) can have positive outcomes, compared with merely integrating (or appropriating) Traditional Knowledge into Western science projects.
- The collaboration between the National Tribal Toxics Council, the Tribal Pesticide Program Council, the Tribal Science Council, and the USEPA to develop tribal exposure scenarios was presented by Jose Zambrana, USEPA. The presentation outlined how the collaborative group is working together, using Indigenous Knowledge to inform Western science protocols, to better understand potential tribal exposure scenarios for more accurate risk assessments.
- Ross Smith,Hydrobiology, Pty Ltd., presented on behalf of Bradley Moggridge, University of Canberra, to discuss how the incorporation of cultural and spiritual values is anticipated to affect water quality management in Australia. He shared a success story of how incorporating Indigenous cultural and spiritual values has helped the planning and engineering design for a second rehabilitation of the legacy Rum Jungle uranium mine.
The Indigenous Knowledge and Values Interest Group intends to build on the momentum of the SETAC North America 40th Annual Meeting in Toronto and continue the important conversations about meaningful collaboration and integration of Indigenous Knowledge with Western Science and have proposed the session “Connecting the Past, Present and Future: Collaborative Efforts between Research and Indigenous and Traditional Knowledge” for the SETAC North America 41st Annual Meeting in Fort Worth.
Author’s contact information: email@example.com
Summaries Published in the March 2020 Issue
Jone Corrales, U.S. Environmental Protection Agency; Marlo Sellin Jeffries, Texas Christian University; John D. Hansen, U.S. Geological Survey; and Natacha Hogan, University of Saskatchewan
Immunotoxicology continues to gain traction at SETAC. We are excited to report that the SETAC North America 40th Annual Meeting in Toronto included the first, full-day platform session focused on immunotoxicology! This was also the third consecutive year that SETAC included an immunotoxicology session in the program. We would like to thank everyone for their interest in this emerging session and for submitting abstracts. The mean number of attendees per platform presentation was just over 50. Presenters from Canada, Japan, Europe, and the United States shared their work addressing the immunomodulatory effects of various stressors using controlled laboratory and field studies. The session started with a focus on in vitro research using cell lines and transitioned to those integrating whole-organism responses. The common thread throughout the session was the complexity of the immune system; a theme that promoted discussion of critical challenges facing the field. To bring each platform presentation to the spotlight, a brief summary of the diverse work that was presented is provided below.
- Ulyana Fuchylo (University of Saskatchewan) discussed how fish living in environments containing diverse pathogens could be at higher risk of infection when exposed to oil sands process-affected water (OSPW). To test her hypothesis, she induced an inflammatory response in a rainbow trout gill cell line (RTgill-W1) and in vivostudy using juvenile rainbow trout.
- James Stafford (University of Alberta) presented data and showed that the dynamic mixture of inorganic and organic fractions of OSPW contain potent immunomodulatory components that influence the viability, homeostasis, and immune functions of mouse macrophages. Furthermore, he discussed how his data showed that OSPW constituents drive macrophage polarization into different functional phenotypes, representing a potentially new bioindicator.
- Cheyenne Smith (West Virginia University) described that reoccurring mortalities of adult and young-of-year smallmouth bass in the Chesapeake Bay watershed are of concern. To determine if mortalities are due to a compromised immune system, Smith explained that she assessed immune function in wild fish by comparing results across four sites that contained different levels of environmental contaminants. Smith interpreted her results as an indication that immune functions (leukocyte phagocytosis, respiratory burst activity, and mitogenesis activity of lymphocytes) for smallmouth bass varied seasonally and across sites.
- Jeffrey Yoder (North Carolina State University), a fish immunologist by training, gave his first presentation at SETAC. Yoder presented an overview of his work using zebrafish larvae as a model for assessing immunotoxicty. He discussed his results on key aspects of innate immunity that he showed were suppressed in larvae upon exposure to five compounds. He noted that these compounds were also known to be immunosuppressive in mammalian models. Finally, Yoder concluded that his data showed the value of using the zebrafish model as an alternative to expensive mammalian models for assessing immunotoxicity.
- Keith Nakayama (Ehime University) discussed the effects of dexamethasone on disease susceptibility using common carp (host) and Aeromonas salmonicida (pathogen) as the challenge model. Nakayama discussed how his results showed that susceptibility to infection was size-dependent for the host. Nakayama ended his presentation by emphasizing the need to develop standardized testing guidelines in the field of immunoeco[toxico]logy.
- Helmut Segner (University of Bern) presented results from a chronic ethinylestradiol (EE2) exposure study using rainbow trout that were later mock infected or infected with the myxosoan Tetracapsuloides bryosalmone, the causative agent of proliferative kidney disease. Segner stated that unexpectedly, his results showed immunoenhacing effects and decreased pathogen susceptibility of EE2-exposed fish. He concluded by stating that his results were in contrast with other similar studies and that his data highlighted the complexity of the immune system and its responses to various stressors.
- Jessica Leet (U.S. Geological Survey) presented findings that exposure to EE2 can differentially modulate disease susceptibility in juvenile largemouth bass infected with Edwardsiella piscicida based upon the concentration of EE2. Leet discussed how her work is further evidence of the complexity of immunomodulators, such as xenobiotics, that can exert both immunosuppressive and immune-enhancing effects.
- Maria Rodgers (University of Southern Mississippi) discussed a study on the effects of oil exposure on susceptibility to infection. Rodgers presented her results showing that Southern flounder exposed to oiled sediment at two different concentrations and challenged with the pathogen Vibrio anguillarum presented a unique pattern of dysregulation with immune-suppressing and immune-enhancing responses at the high- and low-dose exposure, respectively.
- John Hansen (U.S. Geological Survey) discussed how the failure of endangered Lost River sucker in Klamath Lake to reach sexual maturity might be related to the presence of the cyanobacterial toxin microcystin. Hasen tested this hypothesis using a zebrafish model by looking at the effects of microcystin ingestion on innate immunity. Importantly, he discussed how his work also revealed that components of innate and adaptive immunity are compromised by microcystin LR as assessed by RNAseq.
- Leah Thornton Hampton (University of North Texas and Texas Christian University) presented her work that demonstrated cross-talk between the endocrine and immune systems. Specifically, she discussed her findings that phagocytic cell activity was reduced in fathead minnows exposed to the model anti-thyroid compound, propylthiouracil, during early development.
- Natacha Hogan (University of Saskatchewan) presented data on the ability of benzo[a]pyrene and chlorpyrifos to alter immune parameters in juvenile Xenopus laevis. Hogan discussed that her work showed an impairment in the inflammatory response, a reduction in circulating lymphocytes, a decrease in basal circulating monocytes, and an increased expression of cytokines. Her work was one of the first studies that demonstrated immunotoxic potential of these compounds in amphibians.
- Natalie Karouna-Renier (U.S. Geological Survey) discussed the immunomodulatory effects of the flame retardant isopropyl triphenyl phosphates (ITPs) on American kestrel nestlings. Karouna-Renier presented her findings that exposure to ITPs altered innate immunity by assessing phagocytic activity and effects on the abundance of heterophils, monocytes, lymphocytes, and CD4+ T-cells.
- Jamie DeWitt (East Carolina University) presented a study using a C57BL/6 mouse model showed that the perfluoroalkyl ether acid, known by the trade name as “GenX,” can affect the immune system without producing effects detectable in standard toxicity studies. DeWitt concluded that immunotoxicity is a relevant and sensitive endpoint for public and environmental health protection.
The second annual Immunotoxicity Working Group meeting was held the day after the session, where a group of 16 environmental scientists led by the session chairs, discussed lessons learned from the platform session and laid out a plan for immunoeco[toxico]logy to continue gaining visibility at SETAC. The group agreed to publish a Focus Article in Environmental Toxicology and Chemistry in 2020 and to work toward the ultimate goal of creating a SETAC Interest Group. In addition, European scientists in the group expressed a strong interest in submitting an immunotoxicology session proposal for the SETAC Europe 31st Annual Meeting in 2021 in Seville, Spain. Finally, at the SETAC North America 41st Annual Meeting, which will be held from 15–19 November in Fort Worth, Texas, we plan to have another immunoeco[toxico]logy platform session and our third annual Immunotoxicity Working Group meeting. We call for all those working on projects that investigate immune function in model and non-model organisms using controlled laboratory approaches or wildlife studies to submit abstracts to the immunotoxicology session! Meanwhile, if you are interested in learning more about the goals of the Immunotoxicity Working Group, please contact Jone Corrales (firstname.lastname@example.org) or Marlo Jeffries (email@example.com).
“Disclaimer: This document has been reviewed by the U.S. Environmental Protection Agency, Office of Pollution Prevention and Toxics and by the U.S. Geological Survey, Office of Science Quality and Integrity and approved for publication. The views expressed in this document are those of the authors, supported by the U.S. Geological Survey, and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency.”
Marilyne Stuart, Canadian Nuclear Laboratories (CNL) and Malcolm McKee, Canadian Nuclear Safety Commission (CNSC)
The Canadian Nuclear Safety Commission (CNSC) and Canadian Nuclear Laboratories (CNL) organized a session on “Environmental Radiological Sciences” that was held on 7 November 2019 during the Society of Environmental Toxicology and Chemistry (SETAC) North America 40th Annual Meeting in Toronto. This session encompassed a wide range of experts in the radiological aspects of environmental risk assessment including dispersion modeling, characterization of exposure pathways and dosimetry. Others shared their expertise in radionuclide effects monitoring and radiochemistry with respect to developing new methodologies for the detection of radionuclides in various environmental media.
The session succeeded in its goal of providing an opportunity for researchers to meet, exchange ideas and foster collaborations. The plenary session featured eight speakers and the poster period consisted of seven participants, which provided an additional opportunity for the exchange of ideas. Both the poster and the plenary sessions were well attended, and the group had stimulating and respectful discussions around the information presented. A summary of each one of the 15–20 minute talks follows:
- Stacey Fernandes (CanNorth Environmental) opened the first portion of the session with a presentation on fate and transport modeling of Ra-226 and uranium at the decommissioned Beaverlodge Uranium Mine Site located in Northern Saskatchewan, Canada. Making use of 13 years of site-specific water quality data as well as supportive sediment data, the Beaverlodge Quantitative Site Model (QSM) was calibrated. Dose predictions were reviewed in the context of seasonal variability and in the light of recently obtained data on fish tissue burden.
- Sheldon Landsberger (University of Texas, Nuclear and Radiation Engineering Program) followed, first summarizing the history of radioactivity in oil and gas and then providing an evaluation, utilizing Monte Carlo (MCNP) simulations, of radiation doses for workers in the oil and gas exploration sector. Using an Oak Ridge National Lab human phantom to calculate the dose distribution throughout the human body, his team demonstrated the potential for radiation effects in each individual organ based on the typical radioactivity levels found in west Texas oil scale in the United States of America. Based on these results, he advised that for the average oil and gas exploration worker, the dosimeter should be kept at the lower ends of the body instead of the usual chest height.
- Bruno Fiévet (Institut de Radioprotection et de Sureté Nucléaire [IRSN]) presented animated slides of the dynamic modeling of radionuclide transfers from discharges to biota in the marine environment in the English Channel. The nuclear reprocessing plant of ORANO La Hague (France, Normandy) is the main anthropogenic source of radionuclides in the area and extensive monitoring data are available. For Cs‑137, Co-60 and I-129, using the calculated signal in seawater and the observed signal in biota, his team derived dynamic transfer parameters to model radionuclide transfers between seawater and biota. These newly derived parameters values are available to other researchers and regulators with dynamic modeling capabilities.
- Lisa Manglass (Clemson University, Environmental Engineering and Earth Science) closed the first part of the session with her work on the assessment of the impact of low doses of plutonium-239 and iron-55, both alone and in combination, on Escherichia coli, Pseudomonas putida, and Saccharomyces cerevisiae grown in liquid culture. By investigating the uptake and sorption of plutonium-239 in cells grown with and without iron-55, the lab can better understand the impact of cellular ligand production on plutonium uptake and sorption and improve assessments of dose and response.
- Marilyne Stuart (CNL) opened the second part of the session with a presentation on the effects of the exposure to tritium, in the form of tritiated water (HTO) and in the form of organically bound tritium (OBT), from two complementary fish studies (field and lab). Both studies, consisting of 60 days of exposure followed by 60 days of depuration, were carried out at CNL’s Chalk River Laboratories (CRL) in Ontario, Canada in collaboration with IRSN (France). In the field, no effects were observed on survival, fish condition or metabolic indices for internal dose rates reaching 0.15 μGy/h. Tritium exposure, however, increased DNA damage and induced changes in fatty acids of fathead minnows. Tritium also increased the responses of the immune, neural and antioxidant systems. In agreement with the field study results, up to dose rates of 0.65 μGy/h, no effects were observed on survival, fish condition or metabolic indices and, tritium increased DNA damage and modulated the immune responses at the highest exposure levels in the lab study. Changes in the neural system, oxidative stress and fatty acid composition were also observed. No effects were seen on antioxidant activities. Immune markers did not correlate as well with DNA damage markers in a field context. In addition, the phagocytosis activity was much higher in the field compared to the laboratory.
- Andrea Bonisoli Alquati (California State Polytechnic University, Pomona, Department of Biological Sciences) then presented work on the radiation levels in birds associated with the Chernobyl exclusion zone. Captured birds, from habitats differing in environmental radiation levels over more than three orders of magnitude, were individually scanned using a portable gamma spectrometer. External individual dose was estimated using thermoluminescent dosimeters (TLDs) attached to standard aluminum bird bands. It was found that the environmental levels at the site of capture accurately predicted the internal dose received by the birds. Environmental radiation levels also predicted the dose received by the TLDs during the month-long period between subsequent captures for a subsample of birds. The strength of the association, however, varied among closely related passerine species highlighting the limitation of radiological protection approaches based on reference animals.
- David Lee presented his work on groundwater-derived strontium-90 in 12-day old tree swallow nestlings at Chalk River Laboratories (CRL) in Ontario, Canada. At CRL, nesting boxes were installed as close as feasible to groundwater discharge areas or in areas having sediments affected by upstream discharge of Sr-90 contaminated groundwater. For comparison, nest boxes were also installed far from the contaminated areas. Nestlings reared near sediments with groundwater-derived Sr-90 had elevated levels of gross beta in their bone. The maximum calculated skeletal dose rate was 9 μGy/h. Reproductive success of the tree swallows was similar regardless of their nesting location at CRL. There were no indications of DNA damage, as measured by the frequency of micronuclei in red blood cells.
- Wei Wang (Trent University) closed the session with a new method for the measurement of Sr-90 in liquid samples by automated separation, pre-concentration and online ion exchange chromatography coupled with Inductively Coupled Plasma – Mass Spectrometry (ICP-MS). The system requires low sample volumes (10 mL) and minimal sample preparation compared with traditional radiometric and other MS techniques. In addition, the processing time is 22 minutes per sample using a dual column system. Based on a 10 mL sample size, the limit of detection (LOD) and method detection limit (MDL) values were 0.09 ppq (0.47 Bq L-1) and 0.3 ppq (1.57 Bq L-1), respectively. This method was tested on five water samples as part of the International Atomic Energy Agency (IAEA) 2018 Proficiency Test Exercise. The recovery was 99% with a relative standard deviation (RSD) of 11.7%. The method thus provides a powerful tool for the rapid, low level analysis of Sr-90.
The wide array of expertise exhibited by the presenters emphasised the necessity for multiple disciplines to come together to surmount today’s challenges associated with environmental radiological sciences. The research topics span a number of challenges such as the characterization of background radiation, the prediction of the fate and transport of radionuclides under different release scenarios and in various environments, the determination of doses, effects and sensitivities in a wide range of receptor species, the development of an understanding of risks associated with mixed contaminant conditions, and the development of adequate and defensible policies for the protection of humans and biota. Participants expressed their pleasure at being able to attend a session focused specifically on radiological environmental issues at such a wide-reaching conference such as the SETAC. The session organizers would like to thank all the participants, session and poster presenters as well as participating audience members, for their support in making an interesting and enjoyable session.
William L. Goodfellow, Exponent; Timothy J. Canfield, U.S. Environmental Protection Agency – Office of Research and Development; and Patrick D. Guiney, University of Wisconsin
Environmental management and policy is only as good as the science that informs the discussions and ultimate decisions. Without a sound understanding of how environmental systems work and how stressors on these systems can affect ecosystems, programs intended to manage these systems will continually be off target and policies developed to protect and enhance these systems may be inadequate due to the lack of scientific understanding needed to make informed decisions. An important aspect of the science that forms the foundational information needed to make correct decisions for managing these systems and developing policy is that the science and how it was obtained must be transparent, well documented and impartial to the potential regulatory decisions that are under consideration. In short, how do we ensure that our science is objective and our scientists are trusted?
The session covered views and experiences from researcher across academia, business, industry, and government.
The key points of the seven presentations included:
- William Goodfellow (Exponent) presented a talk titled “Practical Examples to Effectively Presenting Science Information and Results Without Advocating Policy or Preference.” He stated up front that as a scientist the presentation of one’s findings is a professional responsibility. He acknowledged that science is not value free, rather expected to be policy neutral and, ideally, policy relevant. Key take home recommendations include:
- Refrain from trying to make presentation or publication titles like a newspaper headline
- Eliminate editorial descriptions of the results by avoiding value-laden words such as vast, substantial, greatly, catastrophic, minuscule, inconsequential
- Remember that journal articles, poster presentations and platforms live “almost forever” on the Internet. Make sure they are as accurate and unbiased as possible
- Larry Kapustka (LK Consultancy) focused his talk on communicating science-based information. He stated to the audience that it is hard work to communicate science-based information. He stated that social-ecological systems are complex and therefore present challenges for communicating the way the systems work. He reminded everybody that humans are wired to make critical decisions relatively quickly, acting on “thin slices” of information, but we are not effectively wired for making critical decisions when there is a large preponderance of information that must be evaluated (i.e., wicked problems). Key take home points:
- Embrace the complexity of the message
- Be upfront about one’s own biases
- Recognize the potential for misinterpretation of the information you present
- Doug Fort (Fort Environmental Laboratories, Inc) focused on the premise that communicating quality science starts at the very beginning of the scientific effort. He stated that disseminating science and scientific presentation starts with program philosophy in a research design. Fort described a program he developed that allows his staff to focus on small scientific projects of interest to them, separate from their contracted work. The goal of the program is to foster scientific enthusiasm in his lab. Key take home points:
- Develop research with no a priori agenda
- Articulate clear scientific questions to address
- Make methods and study design open and transparent
- Provide high levels of credibility by linking conclusions directly to results
- Valery Forbes (University of Minnesota, Ecology, Evolution & Behavior) spoke to the issue that as scientific understanding improves, efforts should be made to integrate these recent advances into the implementation and environmental policy and management. The overarching premise was that environmental scientists are tasked with examining complex ecosystems, identifying key processes that can be simplified through modeling, to assess the severity and likelihood of risk. Forbes supports the position that the scientific basis of ecological risk assessment (ERA) needs to be improved. She points out that problems arise when trying to implement new methods for ERA both from regulators and industry. Key take home points to address these issues:
- Utilize multi-stakeholder working groups to minimize bias
- Maximize transparency of the process and decisions to reduce hiding behind the veil of “best professional judgment”
- Identify a process and criteria for eliminating and replacing less effective methods as the science develops
- Lyle Burgoon (US Army Engineer Research and Development Center, Environmental Laboratory) presented a case for logical and applied ethics analysis of scientific integrity and perceived conflicts of interest in environmental toxicology. He provided several definitions of bias and then proceeded to outline where these biases may enter into the science of environmental toxicology. He pointed out that there is nothing wrong with acknowledging bias and that this level of transparency is actually good for the scientific field of study. Key take home points:
- Treat studies funded by industry, government and foundations equally
- Look at the study, its design, its analyses and its conclusions
- Remove details from the journal review process that will drive logical fallacies (funding sources, author identities)
- Scott Belanger (Procter & Gamble Company, Global Product Stewardship) spoke to the pros and cons of method standardization and regulatory decision making. He pointed out that for the acceptance of information and use of eco-toxic and regulatory decision making, the data needed to be reliable (clearly documented, repeatable, objective, having clear criteria and assessment processes) and relevant (data usable to address specific protection goals and ultimately regulatory decision making, data has exposure relevance and biological relevance, test organisms have environmental significance and proper endpoints are selected). Belanger made a case for why we need non-standard approaches. The key take home points for advocating the non-standard methods are:
- To fill in the biodiversity gaps
- To illuminate unforeseen issues that standard ones cannot
- To provide linkages between the lab and the field
- Christopher Borgert (Applied Pharmacology & Toxicology, Inc.) presented information on why peer review needs an overhaul. He focused his talk on agenda-driven normative science, white hat bias and censorship. Borgert emphasized that the fundamental role of science is to:
- Seek objective information about the physical world in order to understand how stuff works;
- Acknowledge science is about measurements, not about scientists and their affiliation or their values;
- Understand science is empirical, it is about “what is”, and not “what ought to be”;
- Understand the scientific method is unique among forms of human inquiry: it gives prominence to systematically produced data and relegates scientists to the background.
Borgert closed his presentation by proposing a first-step solution towards an emboldened peer review process. The key points to this proposed peer review process are:
- Conduct double-blind peer review
- Use a “Transportation Safety Authority-style” (i.e. “special-enhanced”) peer review
- Embolden Editors to address bias
Conclusions from the Session
The attendance at this session was very high (between 200 and 225 participants) for each talk, with many questions and opinions expressed by the audience through the lively and interactive discussion periods. The interest level for the participants was such that approximately 50 stayed after the session ended and continued the discussions for 50 minutes into the lunch period. The Session Chairs interpreted the numerous comments and audience willingness to stay after the session concluded for further discussion as reinforcing that there is a strong, shared concern by many in SETAC that bias is very much a concern and presenting unbiased science is an interest across all sectors to address these issues regardless of when and where they arise. There remains a clear desire to see more sessions focused on this topic and related topics on how SETAC is identifying and reducing bias – in all its manifestations – to better our science to make it open, transparent and advocacy neutral for policy or preference.
Summaries Published in the February 2020 Issue
Jake Martin, Monash University; Erin McCallum and Tomas Brodin, Swedish University of Agricultural Sciences
On the third day of SETAC Toronto, if you stopped by Room 718A, you would have seen a crowd of academics, government and industry scientists captivated by talks on the impacts of chemical contaminants on animal behavior. Our session was inspired by the ever-increasing use of animal behavior as a sensitive endpoint to measure the adverse and often sublethal effects of environmental pollutants. In our session, we focused on ‘incorporating environmental complexity and relevance’ and were eager to hear from scientists who have pushed the boundaries of this field by incorporating the complexities of natural conditions. We had two objectives for our session. First, during the platform presentations, we wanted to showcase new findings, focusing on research that included higher levels of environmental complexity. Second, we led a panel discussion with leaders in the field to address the current challenges and criticisms that face the new and growing field of behavioral ecotoxicology.
The platform presentations were well received, with over 100 delegates at one stage. An outstanding group of researchers from a wide variety of career stages delivered these presentations, namely Anoosha Attaran, Apolline Chabenat, Hossein Mehdi, Alexandra Steele, Paul Blanchfield, Mirco Bundschuh and Bob Wong.
Attaran opened the session with a compelling talk about the impacts of selenium on social learning and information transfer in fish, reporting that selenium exposure can reduce the efficiency social learning in fish. More generally, Attaran’s work highlighted that social learning is an overlooked but important aspect of animal behavior in regard to chemical pollution. Chabenat followed with an exiting talk on the impacts of antidepressant mixtures on the burying behavior of shore crabs and cuttlefish. Chabenat reported that for both species, burying behavior was modified by the antidepressant ‘cocktail’ (specifically, fluoxetine and venlafaxine) at environmentally realistic concentrations, with likely consequences for individual survival. Mehdi’s research took us one step closer to the field, by showing that fathead minnows exposed to municipal wastewater effluents had higher metabolic rates and behaved less boldly—but only during exposures in the summer and not the winter. His work highlights the need to account for how seasonality may dampen or exacerbate the effects of environmental stressors. Next up, Steele presented her work on the behavioral impacts of per- and poly-fluorinated alkyl substances (PFAS) on wild crayfish living in contaminated ecosystems. Steele showcased the benefits of crayfish as a model organism for behavioral ecotoxicological monitoring, while also reporting the potential impacts of PFAS on antipredator behavior of crayfish across field sites of varying levels of contamination.
After the break, the crowd returned, eager to learn more about behavioral ecotoxicology. Blanchfield started us off by presenting new findings from the landmark Experimental Lakes Area whole-lake exposure with ethynilestradiol. He showed (with videos too!) that the few male fish left defending nests in the exposed lake were bombarded with aggressive females, perhaps disrupting their ability to raise their offspring. This will certainly be an interesting addition to this already important whole-ecosystem study. Next up, Bundschuh delivered an interesting conceptual note about measuring the effects of pollution across ecosystem boundaries. He highlighted some of his group’s current work tracking pollution transfer from aquatic to terrestrial environments using replicated large-scale artificial streams. To close the platform presentations, Wong gave a captivating overview of the benefits and importance of animal behaviur in ecotoxicology. Explaining how, as a behavioural and evolutionary ecologist, he was drawn to the field of ecotoxicology. He gave a summary of his years of work studying the behavioral impacts of the hormonal growth promotant (Trenbolone) on fish behavior.
We wrapped up our session by holding an open panel discussion comprising Bryan Brooks, Paul Blanchfield and Bob Wong. The panel explored key topics including the use and standardization of behavioral endpoints for legislation, and if we can predict the ecological and evolutionary impacts of behavioral disruption for wild populations. A crowd of over 50 delegates stayed to listen and many participated in the conversation about the future of the field. The panel even ran well into the coffee break, with many delegates sacrificing the strong need for coffee to continue the discussion.
Overall, lots of new and exciting behavioral science was presented and discussed during the session, and also on the wonderful posters that accompanied the platform presentations. The interest in this field is certainly growing and it will be exciting to see how it develops until the next SETAC meeting.
Ralph G. Stahl, Jr., Dupont (retired) and Phil Dorn, PB Dorn Associates
The SETAC North America Senior Resource Group (SRG) helped to sponsor two sessions at the SETAC North America 39th Annual Meeting, one of which was a Special Forum called “Oh, The Changes I’ve Seen Over the Past 30 Years.” This was a new session format for SETAC called “storytelling.”
There were nine speakers who spoke about how their careers started and evolved, and the role that SETAC played. It began with Gary Ankley, USEPA, who discussed a career that has spanned sediment toxicology, endocrine disruption and now mechanistic toxicology including development of the adverse outcome pathway framework. Ankley was followed by Scott Belanger, P&G, who showed how his research focus spanned various types of mesocosms, both in the field and laboratory, and noted the importance of connecting the results from both types. Ceil Mancini, AECOM, described her love of the sea that began as a young girl and continues today. A benthic biologist by training, she noted that a major challenge getting into the field at her first job was finding a pair of chest waders that fit her. Ron Kendall described how wildlife toxicology was a very small field when he began his career more than 30 years ago, but now has become a major focus area of SETAC and other groups. Teresa Norberg King, USEPA, gave an excellent overview of how whole effluent toxicity testing went from an “experiment” to a test that is widely used by regulatory agencies. Ellen Mihaich, private consultant, discussed being a “endocrine disruptor groupie,” and in doing so showed how the early reports of disruption in marine welks has evolved into national and international efforts to understand how various chemicals cause harm to invertebrates and vertebrates alike. Pieter Booth, Ramboll, discussed the evolution of ecosystem services from a theoretical consideration to a process to estimate the natural resource value of specific habitats or ecological processes. Annette Guiseppi-Elie, USEPA, gave an interesting overview of how exposure science has evolved over time, and where today it is a much more integral component in the estimation of risk to human health and the environment. Finally, our last speaker, Will Gala, Chevron, provided his view that ecological risk assessment should be used only in specific situations, not wholesale, for evaluating contaminated habitats.
All in all, these nine presenters covered a lot of ground in the morning session, often to a standing-room only crowd, and in a timeframe designed for eight speakers instead of nine.
Summaries Published in the January 2020 Issue
Matthew Lambert, U.S. Environmental Protection Agency and Bonnie Brooks, Minnesota Pollution Control Agency
Soil background is important to consider when making risk assessment decisions for cleanup or disposal of contaminated soil. Too often, soil background is either not used at all or used inappropriately when making important decisions. This session offered about 70 audience members some insight into how soil background has been effectively used in risk assessment.
Soil screening values are used to evaluate whether contaminants pose risks to people or the environment. Since they are intended to be protective of people or ecological species, they are derived using toxicity data, exposure parameters and contaminant specific parameters, but they don’t account for the amount of a contaminant present in soil due to background. In some cases, soil screening values for a contaminant are below soil background. When background concentrations are similar to or above soil screening levels, it is important understand the contribution from soil background and include this in risk assessment.
Topics covered included natural and ambient soil background studies already performed, how data from studies have been used to establish both natural and ambient soil background values, important items to consider when using these studies and when deriving soil background values, and how soil background has been used in risk assessment.
Natural background of metals in soil, with a special emphasis on arsenic, was the subject of the first half of the session.
- Bonnie Brooks, with the Minnesota Pollution Control Agency and session co-chair, discussed how they re-analyzed some of the U.S. Geological Survey (USGS) soil samples, including arsenic among other metals, using the U.S. Environmental Protection Agency’s (USEPA) analytical method to use that data to determine soil background. Many audience members were surprised to learn that results from the two analytical methods differed.
- Leah Leon, from Canada North Environmental Services, discussed how they developed an approach to determine soil background in areas of Canada where higher concentrations of metals are present due to natural geologic conditions. Emphasizing arsenic, Leah also discussed how they handled soil background in surrounding areas that did not contain elevated background concentrations.
- Christine Peterson of EHS Support compared two methods for determining potential risks from soil background using four reference sites. In some cases, they found risks were elevated based on soil background alone, without consideration for anthropogenic sources.
- Damon Delistraty, from Washington State Department of Ecology, compared state-wide and local soil background concentrations of arsenic to human and ecological soil values. Delistraty discussed this in context of a policy used for arsenic at the United States Department of Energy Hanford Site located in Washington.
Ambient soil background was the subject of the second half of the session, which included discussions regarding both metals and organics.
- Sydney Chan, with the USEPA, explained how they completed an ambient soil background study of metals and polycyclic aromatic hydrocarbons (PAHs) in eight cities in the southeastern United States. Audience members were excited to hear that their long-awaited dataset would be posted on USEPA’s website soon.
- Matt Lambert, also with the USEPA, discussed how they reviewed dioxin, furans and polychlorinated biphenyl (PCB) soil background studies conducted at Superfund sites. They looked at how this information was used in risk assessment and management decisions.
- Casy Fath from Barr Engineering discussed ambient soil background for per- and polyfluoroalkyl substances (PFAS). Fath also talked about how they have been keeping track of how different regulatory agencies require PFAS in soil to be evaluated.
- Kanan Patel-Coleman of AECOM discussed how they developed a model to quantify the contribution of forest fires to ambient PAH soil background in California. Most interesting was the finding that PAHs from forest fires did not contribute significantly to ambient PAH concentrations.
Take home messages:
- Consideration for both natural and ambient soil background in risk assessment is important.
- Data from existing soil background studies may be suitable to use to establish soil background without going through the effort of conducting a soil background study.
- Results differ between the USGS and the USEPA analytical methods for metals in soil.
- Geological conditions present in an area may lead to elevated natural background concentrations in that specific area, which may differ significantly from surrounding areas.
- Urban areas may also present areas of elevated concentrations that may not be attributable to a release, presenting technical and policy challenges.
- Risks to people or ecological species may be present from naturally occurring metals in soil.
- There is no widely accepted standard approach for incorporating background into risk assessment.
- Naturally occurring fires are likely not a significant source of ambient polycyclic aromatic hydrocarbon concentrations in soil.
Author’s contact information: Lambert.Matthew@epa.gov
Carolyn B. Meyer, Arcadis, Inc.; Katherine E. Horak, U.S. Department of Agriculture; and Barnett A. Rattner, U.S. Geological Survey
The pressures to control invasive and pest vertebrates to meet societal goals and yet protect wildlife is becoming increasingly challenging. This session, including eight platform presentations and two posters, discussed recent advances in assessment of risks to non-target species of control practices and tools used to control invasive wildlife using more species-specific and/or safer toxicants, contraceptives and gene editing.
The session addressed four themes: anticoagulant rodenticide (AR) research, genetic technologies, population modeling, and risk assessment and mitigation. John Elliott, Environment and Climate Change Canada, kicked off the AR presentations with an analysis of the current incidence of wildlife exposure to ARs in various countries. For raptors in western Canada, second generation AR poisoning accounted for up to 7% of reported deaths, 33% of expected deaths based on lethal hepatic thresholds, and up to 60% of raptors may have sublethal injury (increased clotting time). Barnett Rattner showed wildlife exposure to second generation ARs in the U.S. continues despite recent risk mitigation measures that include restricting second generation AR use, packaging size, and types of bait and bait stations. Richard Poche, Genesis Labs, promoted the less persistent first generation ARs as a viable alternative to other rodenticides. He discussed misconceptions about resistance to and effectiveness of first generation ARs, importance of antidote availability, and correct dosage as safety measures. Virginie Lattard, VetAgro-Sup in France, presented her results from modifying the proportion of different stereoisomers in second generation AR baits to obtain a new efficient generation of anticoalgulants that have a reduced half-life in rats, reducing exposure risk of non-target species.
For genetic technologies, Katherine Horak explained gene drive, how it can be used to change inheritance probability, and how gene silencing can cause species-specific mortality. Both are promising new tools for pest control that theoretically will not harm non-target species. To use these technologies requires understanding where to apply them most effectively. Richard Erickson, USGS, used spatially-explicit population modeling to decide where to control invasive Asian carp. His goal was to prevent spread of bighead and silver carp by identifying where to target controls, apply deterrents and collect better data. He incorporated pool-specific life history and movement data in the model to predict specific pools to target with various controls such as RNA interference, toxic species-specific microparticles or synthetic biology (re-program an organism to produce toxic substance). Carolyn Meyer also discussed population modeling as a tool useful for predicting rates of pest population recovery after rodenticide application and for assessing secondary poisoning risk by quantifying effects on the population size of non-target species. Chiara Accolla, University of Minnesota, used population modeling to address impacts of invasive species on threatened species. Accolla illustrated how the brown trout can reduce and extirpate threatened greenback cutthroat trout populations as well as exacerbate chemical (estrogen) impacts. She pointed out that such models can explore potential consequences of invasive species control measures on the fish community.
While many of these presentations touched on application of the various tools for use in risk assessment or mitigation, Karl Campbell with Island Conservation fully explored a real-world example of assessing and managing risk associated with invasive rodent eradications on islands using anticoagulants in his presentation. Invasive rodents cause 30% of all extinctions; to-date there have been 640 eradications of invasive rodents on islands using rodenticides. Risk from secondary poisoning to wildlife, livestock and humans is assessed against conservation benefits using food web analyses, evolutionarily significant units, prioritization of exposure pathways and population viability assessments. If risk is unacceptable, mitigation options including captive holding are identified and implemented. Support of the island community has been critical for the success of this process. Philippe Berny, Vetagro-Sup, closed the session with a presentation on recent advances in risk assessment and monitoring of rodenticides in Europe. Non-target arthropods and toxicokinetic/toxicodynamic models are being considered for aquatic risk assessments. For terrestrial risk assessments, a broadening of scope to include amphibians, reptiles or bats is being considered. These presentations from scientists in academia, government and industry provided a balanced perspective on the challenges and possible solutions for safer vertebrate pest control.
Hans Sanderson, Aarhus University; Scott Belanger, Procter & Gamble; Dimitri P. Abrahamsson, University of California; and Dorte Herzke, Norwegian Institute for Air Research
The focus of the session was large polymeric substances, rubbers and macroplastics in environmental risk assessment. The classical view that endpoints used to quantify organism stress are a result of biological uptake into tissues is now clearly expanding to include effects (both internal and external) resulting from physical interaction with the organism. Physical effects have been traditionally disregarded as less toxicologically relevant and outside the traditional theorem of dose-dependence by Paracelsus for ascribing acute and chronic toxicity to chemical exposure, and they are now also relevant for consideration in environmental assessment. Until recently, polymers and macroplastics have been exempt in most regulatory programs but this is now being revisited. Analytical methods for detection of presence, evaluation of exposures in laboratory studies, and methods to confirm environmental exposure models are challenging for many functionalized and sorptive materials among these polymers, rubbers in synthetic turf and macroplastics. In this session and for the first time, we sought to unfold the state-of-the-science of the challenges polymers represent for analytical chemistry, ecotoxicology, fate and exposure in the aquatic environment and to discuss what these challenges mean in a regulatory context.
A high interest for the session was expressed through the presentations, questions and answers at the platform session among the more than 130 participants, with standing room only for the entire session and the discussions at the poster session. In addition, a World-Café style workshop was held during the lunch break the following day, with a focus on the analytical challenges facing polymers attracting an additional 25+ participants with a broad geographical and sectorial spread.
We had platform and posters presentations from North America, Europe, Africa and Asia, covering academia, business and government. The session covered views from different experts and stakeholders from the Joint Research Centre (JRC), an EU Member state, industry and the European Food Safety Authority (EFSA) followed by an interactive plenary discussion.
The session covered the following key points:
- Hans Sanderson, Aarhus University, introduced the session and set the scene by providing an overview of the science regarding aquatic toxicity of polymers and the challenges with regards to risk assessment.
- Monica Lam and Yiping Sun, P&G, presented first the analytical challenges but also emerging methods to quantify polymers in aquatic samples in support of toxicity testing.
- The aquatic toxicity of cationic polyquateriums was reviewed and presented by Jessica Brill, P&G, and Anna Brun, Aarhus University, who showed the challenges with the standard tests when testing sorptive materials.
- We had a concrete case study from a cationic biocide polymer in regard to assessing the environmental risk in a regulatory process presented by Daniel Cros, Pareva, and Cyril Durou, Cehtra, and showed the challenges they faced in this process.
- Hlengilizwe Nyoni, University of South Africa, presented pyrolysis-gas chromatography mass spec methods they apply to quantify microplastics in water samples in an African context.
- Zoei Diana, Duke University, presented short-term effects of anemones consumption of plastics and novel assessment endpoints pertaining to crown size.
- The last platform presentation was given by Todd Gouin, TG Environmental Research. He presented “Toward the Development and Application of an Environmental Risk Assessment Framework for Microplastic,” summarizing the findings from International Council of Chemical Associations symposium.
In addition, a set of posters covered new methods and regulatory procedures regarding polymers, see abstract book for details.
At the upcoming SETAC Europe conference in Dublin, there will be a follow-up and in-depth platform and poster session specifically on the environmental risk assessment of polymers. We are also planning an additional open workshop on polymer toxicity analysis during the meeting in Dublin. The polymer related activities are organized by the Improved aquatic Testing and Assessment of Cationic Polymers (iTAP) project (https://projects.au.dk/itap/) supported by Cefic LRI ECO46.
Polymer Analytical Workshop
For the workshop, representatives from industry, government, academia and contract research organizations (CROs) collectively shared their knowledge and insights on the state of the science of new innovative approaches and limitations with a variety of well-established analytical approaches for water-soluble polymers and other difficult chemistries in environmental safety studies.
The purpose of this workshop was to:
- Provide a “prospective review” of published and unpublished analytical approaches for polymers and other similar and difficult to analyze materials in the context of environmental safety testing
- Identify general challenges with water-soluble polymers – limitations of current methods
- Discuss the feasibility of a universal approach and instrumentation that is accessible to scientists at CROs and in academia, industry and government
Workshop discussions focused on guidance and watch-outs, strengths and weaknesses of different analytical approaches that could be used for quantitation, such as wet chemistry, non-specific methods and mass spectral techniques. Scenarios where simpler approaches could be possible and extraction strategies for polymers from matrix were also discussed.
Key findings for wet chemistry and non- or semi-specific approaches are that they have limited scope of utility with respect to testing applications. Potential issues would include limits of detection or quantitation, specificity, clear articulation and knowledge of assumptions, and knowledge of the testing matrix. However, there could be scenarios where these methods could be useful; these are envisioned as situations where data is available to support the use of the methods by demonstrating the polymer is stable to degradation and sorption, can be distinguished from background, and has moderate to low ecotoxicity. On the other hand, mass spectrometry offers the potential for delivering high sensitivity, robust approaches for polymer identification, structure characterization and quantitation to meet environmental safety study needs. However, there are significant development efforts and more attention is needed from analytical, mass spectrometry and environmental safety communities in order to address the various technical and accessibility challenges.
A common theme from the sub-group discussions is that a well analytically characterized polymer is a key aspect to guide the selection of an appropriate analytical method and the design of environmental safety studies. An understanding of the monomers, residuals, molecular weight ranges and other physical-chemical properties are important in selecting the analytical method, in addition to the specific need. This topic is the subject of a recently submitted poster abstract for SETAC Europe in Dublin.
Conclusions from the Session and Workshop
The platform and workshop help set the stage for a future state where polymers will be routinely reviewed in international chemical management programs, similar to existing and newly registered substances. Polymers, however, still provide scientists with unique challenges associated with fate and exposure assessment as well as hazard assessment. Regarding fate, polymers will certainly be considered as UVCBs (unknown or variable composition, complex reaction products or of biological materials), which always present difficult characterization and analytical challenges. Care will be needed to consider new ways to anticipate releases of constituents into environmental matrices. On the hazard side of the risk assessment process, the realization that physical effects may be environmentally relevant open up new considerations for characterizing exposure (dose) – response and aspects of exposure relevance so that the true environmental risk of polymeric substances can be revealed. SETAC will be a key venue for these issues to be explored in a tripartite manner.
Carys L. Mitchelmore, UMCES Chesapeake Biological Laboratory, and Iain Davies, Personal Care Products Council (PCPC)
Overview of Session
The goal of the session was to bring scientists from academia, business, government agencies and other stakeholders together to discuss research regarding the environmental risk of UV filters in aquatic ecosystems. As an emerging but rapidly expanding area of research, many more talks were submitted for this session than we were able to accommodate, and so presentations were selected to represent the diversity of topics from environmental monitoring, chemical fate, toxicology and risk assessment.
Concerns over the environmental impacts of UV filters have received considerable attention in recent years, particularly with respect to coral species, and has led to legislation and policy action restricting sunscreens despite very limited or no data on their environmental concentrations or toxicity to reef ecosystems. While the use of UV filters as active ingredients in sun protection products is widely documented, these materials are also used in many other consumer products, such as plastics, paint, apparel, and may even come from natural sources. Therefore, multiple potential point and diffuse environmental sources of UV filters to the aquatic environment exist, such as bathers and swimmers, wastewater treatment plants and in land run-off due to leaching from products. Monitoring studies have shown highly variable spatial and temporal concentrations in environmental matrices, with the majority of seawater concentrations being reported in the parts per trillion or low parts per billion range.
Risk assessments require knowledge of the concentration of the chemical of concern in the aquatic environment and the concentrations that cause damage to the species of interest. Therefore, the current session brought together scientists working in all freshwater, estuarine and marine locations that have investigated the sources, occurrence and concentration in environmental matrices, fate and effects of UV filters in the aquatic environment, together with industry representatives discussing environmental risk and the potential trade-offs with human health concerns. The session aimed to advance our knowledge of the environmental risk that UV filters may pose and to start a scientifically grounded discussion on the implications and research needs of these compounds in the environment.
As mentioned earlier, presentations were balanced to provide new information on the concentration and fate of UV filters in the aquatic environment (presentations 1–3), their toxicity to aquatic species (presentations 4–7) and a risk assessment summary (presentation 8).
Key points from the eight presentations included:
- The first three presenters discussed issues regarding the concentration and fate of UV filters in aquatic systems to understand potential exposure. Steven Landeweer, Florida International University, found low parts per trillion levels of oxybenzone in Biscayne Bay and investigated the use of silicone passive diffusion releasers to prepare exposure solutions from sunscreens. Equilibrium concentrations varied with time and salinity, although only the parent compound was measured.
- Jean-Luc Boudenne, Aix Marseille University-CNRS, reported on the levels of UV filters in Mediterranean beach waters and in chlorinated seawater swimming pools. Results highlighted the variability of concentrations by site, distance from shore, depth, time of day and number of people in the water. In beach samples overall, no or low parts per trillion levels of oxybenzone and avobenzone were found, the highest concentrations (also parts per trillion) seen were for octocrylene. Octocrylene was also the highest measured in the swimming pools in low parts per billion concentrations, which was attributed to its lack of reactivity to chlorine and photostability in laboratory studies compared with the other UV filters.
- The Chesapeake Bay study presented by Ethan Hain, University of Maryland Baltimore County, showed water concentrations in the low parts per trillion concentration for up to nine organic UV filters and found a linear correlation between oxybenzone and octocrylene levels. Oxybenzone appeared higher near known wastewater treatment plant (WWTP) effluents but did not correlate with sucralose levels. Higher concentrations of UV filters in sediment were generally observed at sites with the higher water concentrations and UV filters were present in oyster tissues.
- The next four presentations focused on studies investigating the toxicity of UV filters, mainly oxybenzone to corals, anemones and Daphnia spp. Diana Slijkerman, Wageningen University, in two coral species coupled a six-week long field-relevant oxybenzone exposure with one of the main drivers of coral bleaching, elevated temperature. The study highlighted limited impacts of oxybenzone alone, species-specific impacts, with Acropora spp. being more sensitive. Effects were much more significant for temperature than oxybenzone, which slightly accelerated Acropora spp. mortality in the higher temperature treatment.
- Danielle Stromberg, Cerege, presented for Alice Tagliati, Heriot-Watt University, on the toxicity of mineral (titanium dioxide) sunscreen formulations (at parts per billion and million concentrations) to adult and larval corals and anemones, again combining these exposures with increased temperatures as projected for future climate change scenarios. Impacts on multiple biological endpoints in sunscreen exposed adult coral were observed in the 12-day exposures and temperature elevation did not enhance the negative effects, although heat-stress enhancement was observed in short-term (24hr) anemone experiments. Acropora fertilization success was not impacted by the two sunscreen formulations, although one of them did result in a higher number of abnormalities (<10%).
- Continuing with adult coral exposures, Annaleise Conway, UMCES Chesapeake Biological Laboratory, reported oxybenzone 96-hour lethal concentrations to 50% of the population (LC50s) in the hard coral Galaxea at ~6mg L-1 (nominal concentration), which is the first reported value in an intact hard coral species and much higher than the only reported value in intact coral (i.e., coral larvae) and orders of magnitude above levels commonly found in seawater near coral reef locations.
- Completing the toxicity discussion, Faith Lambert, University of Florida, investigated the chronic toxicity and acute gene expression of three UV filters (parts per billion concentrations; including oxybenzone) to Daphnia. No effects on molting frequency, growth, reproduction or production of males were observed, but at the highest doses (all orders of magnitude above reported surface water concentrations except for oxybenzone, which was within one reported range), all UV filters caused developmental deformities in offspring and 4-methylbenzylidene camphor (4MBC) increased the time to maturity. Gene expressions were not altered.
- To summarize the session, Iain Davies, Personal Care Products Council, gave an overview of the state of the science and challenges regarding the environmental risk assessments of UV filters. He presented a new a tool to ensure that data used in risk assessments is of sufficient quality for inclusion and presented a way forward for determining the risk of chemical contaminants to coral species.
Conclusions from the Session
The detection, toxicity and environmental risk of UV filters in aquatic ecosystems is a rapidly expanding and emerging field of research. Policy decisions have been made on limited (or no) scientific data, and there are numerous gaps in knowledge critical for risk assessments. However, since the session last year and as evidenced by the four-fold increase in abstract submissions this year, research is being conducted to fill these data gaps. This session highlighted the variable (space and time) concentrations of UV filters, that all were measured in the ng L-1 (parts per trillion ranges) and that reductions and transformations occurred by photolytic pathways or reactions with chlorine. Limited acute and toxicological impacts were observed in three intact adult coral species and Daphnia exposed to environmentally relevant (or higher) concentrations of UV filters, although impacts could be seen at the higher doses and both oxybenzone and titanium dioxide, with oxybenzone exacerbating heat induced impacts in corals. The potential impact to corals and other aquatic organisms needs more research given the highly variable responses observed in the toxicity of oxybenzone between studies. The studies reported in this session show limited impacts to corals exposed to oxybenzone at parts per billion and parts per million concentrations, which contrast the previous study presented during policy decisions. Furthermore, correlations among studies would be greatly enhanced if standard acute and chronic toxicity testing procedures were used and analytical verification of exposure concentrations were conducted. Differences in the quality of data and its importance for consideration for inclusion in risk assessments was highlighted, and a data assessment tool for all aquatic species and a risk assessment framework for corals was presented. It is essential that scientists from academia, business, government agencies and other stakeholders continue to work together to increase the wealth of data available regarding the environmental concerns of UV filters. The discussions from this session are planned to be continued in 2020 at SETAC’s Europe and North America meetings.
Henry Kruger, Eurofins US; Gertie Arts, Wageningen Environmental Research – WUR; and David Olszyk, U.S. Environmental Protection Agency
Plants are the basis for all ecological systems and are affected by a broad range of environmental toxics issues. This session, organized by the SETAC Plant Interest Group, welcomed contributions that focused on new developments in plant ecotoxicology and the use of plants in risk assessment of chemicals and other stressors. The current risk assessments for chemicals usually consider risks for primary producers based on standard tests. Higher-tier approaches are only utilized if plants are the most sensitive for a specific chemical or if these organisms are affected indirectly. These higher-tier approaches might cover both experimental and modeling studies. Besides the fact that chemicals can affect plants, plants can also accumulate and biodegrade chemicals and thus contribute to lower exposure concentrations. This ability of plants is potentially useful for phytoremediation and mitigation purposes and thus, contributions to this topic are also welcome. In addition to these topics, and especially of interest in the context of this SETAC meeting in Toronto, we encouraged contributions that considered risk assessment for invasive plant species and endangered species. Presentations covered aquatic plants (algae and macrophytes) and terrestrial plants. We encouraged presentations that: 1) described new or validated testing methods in lower and higher-tier assessments; 2) addressed reproductive endpoints in terrestrial plant studies; 3) presented new studies or in silico modeling efforts on evaluating effects on plant communities at the field and landscape level; 4) described ecological interactions between plants and other species in relation to stressor exposure, e.g., indirect effects with microorganisms; 5) examined the use of higher-tier testing methods in risk assessment, including plant modeling approaches; 6) and evaluated the effects of herbicide drift on non-target plants. Additionally, presentations highlighted local or regional plant ecology issues for Canada.
The key points from the eight platform presentations included:
- Verena Sesin, Trent University, began the session by describing glyphosate effects and accumulation in native and invasive wetland macrophytes. This information will be useful for environmental risk assessments of glyphosate spray applications in wetlands and for effective and sustainable wetland management.
- Sharareh Dehghani, University of Guelph, evaluated potential use of Alyssum for phytoremediation of nickel contaminated soil at the Port Colborne site in Ontario, Canada. The study showed that phytoremediation using Alyssum spp. may not be an effective approach for this site.
- Ryan Bergin, Queens University, evaluated mercury concentrations in edible plant and fungi species of Iqaluit, Nunavut and the surrounding area, and indicated significant differences in mercury concentrations plant and mushroom species.
- Zhu Hao Yu, University of Toronto, described duckweed–microbe interactions in the elimination of benzotriazole, a corrosion inhibitor, from salt-contaminated water. The results suggested that duckweed has potential to remove benzotriazole from water by biotransformation.
- Sarah Graetz, University of Guelph, provided information on the toxicity of novel fire suppression gels to plant germination and emergence. They reported a large variation in toxicity between the fire suppression gels tested, providing information for a better understanding of the potential effects of fire suppression gels on terrestrial ecosystems.
- John Green, John W. Green-ecostats, reviewed analysis of non-target terrestrial plant studies concerning crop-protection chemicals, including recommendations to eliminate errors and improve the quality of results.
- Dwayne Moore, Intrinsik Environmental, Inc., described a large-scale field spray drift study to evaluate downwind effects of herbicides on non-target plants. No significant herbicide effects were observed in navy bean or lettuce at downwind distances of 30 feet or further from the edge of the application area. The results from this field study contrasted with the higher or larger predicted effects based on modeled spray drift curves and greenhouse bioassays.
- Gertie Arts, Wageningen Environmental Research – WUR, presented experimental studies, which provide long-term data sets for testing population models for Lemna and Myriophyllum spicatum. Results showed an increasing variability in response over time but a clear seasonal pattern with slight declines in frond number, respectively shoot length and biomass, during the relatively warm winters. The data will be published to facilitate testing of models of growth for both species.
In addition to the eight platform presentations, there were nine poster presentations dealing with a range of topics including phytoremediation; experimental design, growth responses, measurement endpoints and statistical analysis relevant to non-target terrestrial plant testing guidelines and analysis; evaluation of models used in risk assessments for terrestrial plants, rhizobacteria and the phytotoxicity of biorefinery relevant compounds, herbicide effects on plants, testing of the emergent macrophyte, Glyceria maxima, for a developing OECD test guideline; and a review of recovery of plants and algae from herbicides in aquatic systems.
Conclusions from the Session
Plants are affected by a wide range of environmental contaminants, including herbicides applied for weed management and fire-suppression chemicals, to name a couple. New experimental data, as well as improved testing methodologies and methods of statistical analysis, will provide important tools for determining the risk to terrestrial and aquatic plant systems for these contaminants.