Browsing by Subject "risk assessment"

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Biological control benefit-risk analysis; Heimpel et al. Ecological Applications
(2024-05-06) Heimpel, George E; Abram, Paul K; Causton, Charlotte E; Celis, Sabrina L; Coll, Moshe; Hardy, Ian CW; Mangel, Marc; Mills, Nicholas J; Segoli, Michal; heimp001@umn.edu; Heimpel, George E; University of Minnesota Heimpel Laboratory
The release of biological control agents has been an important means of controlling invasive species for over 150 years. While these releases have led to the sustainable control of over 250 invasive pest and weed species worldwide, a minority have caused environmental harm. A growing recognition of the risks of biological control led to a focus on risk assessment beginning in the 1990s along with a precipitous decline in releases. While this new focus greatly improved the safety of biological control, it came at the cost of lost opportunities to solve environmental problems associated with invasive species. A framework that incorporates benefits and risks of biological control is thus needed to understand the net environmental effects of biological control releases. We introduce such a framework, using native biodiversity as the common currency for both benefits and risks. The model is based on interactions among four categories of organisms: (i) the biological control agent, (ii) the invasive species (pest or weed) targeted by the agent, (iii) one or more native species that stand to benefit from the control of the target species, and (iv) one or more native species that are at risk of being harmed by the released biological control agent. Conservation values of the potentially benefited and harmed native species are incorporated as well, and they are weighted according to three axes: vulnerability to extinction, the ecosystem services provided, and cultural significance. Further, we incorporate the potential for indirect risks to native species, which we consider will result mainly from the ecological process of agent enrichment that may occur if the agent exploits but does not control the target pest or weed. We illustrate the use of this framework by retrospectively analyzing the release of the vedalia beetle, Novius (= Rodolia) cardinalis, to control the cottony cushion scale, Icerya purchasi, in the Galapagos Islands. While the framework is particularly adaptable to biological control releases in natural areas, it can also be used in managed settings, where biological control protects native species through the reduction of pesticide use.
Caries Management By Risk Assessment and the Effect On Caries Diagnosis and Oral Health Behaviors
(2018-10) Kriegler, Krista
Objective: To determine whether a caries management by risk assessment tool improves oral health behaviors and results in less caries diagnoses over time. Methods: A sample consisting of 207 patient records from the School of Dentistry (SOD) dental hygiene clinic were screened for inclusion and exclusion criteria. Inclusion criteria for the control group included patients eighteen years of age or older with their first visit to SOD dental hygiene clinic between years 2010-2011, no record of CAMBRA completion, and two or more dental hygiene clinic visits. Inclusion criteria for the intervention group included patients eighteen years of age or older with their first visit to the SOD’s dental hygiene clinic between 2012-2016, two or more completions of CAMBRA, and two or more dental hygiene clinic visits. Using the CAMBRA form, the following changes in protective factors and risk factors for the experimental group were recorded using a standard form: visible heavy plaque on teeth, drinks water from fluoridated municipal supply, use of fluoride toothpaste at least once a day, use of fluoride toothpaste at least 2xday, use of fluoride mouth rinse (0.05%NaF) daily, use of 5000 ppm F fluoride toothpaste daily, and chlorhexidine prescribed/used one week each of last 6 months. Results: A total of 207 patient records comprised the study sample. One hundred subjects were in the control group and one hundred and seven were in the intervention group. In both the control and intervention groups, at least 50% of the subjects presented with active caries at visit one. The total number of visits ranged from two to eleven. Plaque scores were significantly higher in the control group at the last visit (p-value=0.0442). Subjects in the intervention group, who completed CAMBRA, had lower plaque scores indicating improved self-care behaviors. However, differences in new caries diagnoses at the last visit were not statistically significant between groups. Although statistical significance was not attained, the percentage of subjects with a new caries diagnosis at the last visit was lower for the intervention group (intervention=18.69%, control=29%). Subjects in the intervention group increased the number of protective factors over the course of their visits, except for the use of a prescribed chlorhexidine rinse. The most common reported protective factor was the use of fluoride toothpaste daily. Over the course of five visits, there was an increase in total protective factors for subjects in the intervention group. Conclusion: The results of this study showed subjects with a CAMBRA improved their self-care behaviors and had lower plaque index scores. Differences in new caries diagnosis were not statistically significant between control and intervention, but the percentage of subjects with a new caries diagnosis at the last visit was lower for the intervention group. The results of this study support existing evidence, as the use of caries management by risk assessment appears to offer a preventive approach to oral health care delivery.
Data and code in support of: Release of live baitfish by recreational anglers drives fish pathogen introduction risk
(2022-06-06) McEachran, Margaret C.; Phelps, Nicholas B. D.; Drake, D. Andrew R.; Mladonicky, Janice M.; Picasso, Catalina; thom4412@umn.edu; McEachran, Margaret; University of Minnesota Department of Fisheries, Wildlife and Conservation Biology; University of Minnesota Department of Veterinary Population Medicine; University of Minnesota Gabbert Raptor Center; Fisheries and Oceans Canada Great Lakes Research Laboratory
This repository contains supplementary information, simulation data, and R computer code to accompany the manuscript titled "Release of live baitfish by recreaional anglers drives fish pathogen introduction risk." The purpose of this project was to quantify the risk of fish pathogen introduction, conceptualized as the number of fish infected with a priority pathogen released in a given year of fishing, under a range of conditions.
Data supporting: Evaluation of neurobehavioral abnormalities and immunotoxicity in response to oral imidacloprid exposure in domestic chickens (Gallus callus domesticus)
(2021-05-10) Franzen-Klein, Dana M; Jankowski, Mark; Roy, Charlotte L; Nguyen-Phuc, Hoa; Chen, Da; Neuman-Lee, Lorin; Redig, Patrick; Ponder, Julia; franz337@umn.edu; Franzen-Klein, Dana M; The Raptor Center
Domestic chickens (Gallus gallus domesticus) were exposed to imidacloprid by gavage once daily for 7 consecutive days at 0, 0.03, 0.34, 3.42, 10.25, and 15.50 mg/kg/day (n = 20 per group; 5 6-week-old males, 5 6-week-old females, 5 9-week-old males, and 5 9-week-old females). The severity and duration of neurobehavioral abnormalities were recorded. Components of the innate and adaptive immune system were assessed with 7 standard functional assays. Temporary neurobehavioral abnormalities were observed in a dose-dependent manner, including muscle tremors, ataxia, and depressed mentation. The effective dose value for the presence of any neurobehavioral abnormalities in 50% of the test group (ED50) was 4.62 ± 0.98 mg/kg/day. The ED50 for an adjusted score that included both the severity and duration of neurobehavioral abnormalities was 11.24 ± 9.33 mg/kg/day. These ED50 values are equivalent to a 1 kg bird ingesting 29 or 70 imidacloprid treated soybean seeds respectively. Immunotoxicity was not documented, either because the assays were insensitive, did not test relevant immune functions, or imidacloprid is not immunotoxic at this dosing schedule in this species. Neurobehavioral abnormalities were a more sensitive indicator of the sublethal effects of imidacloprid than immunotoxicity.
Evaluation of neurobehavioral abnormalities and immunotoxicity in response to oral imidacloprid exposure in domestic chickens (Gallus gallus domesticus)
(Journal of Toxicology and Environmental Health, Part A, 2020) Franzen-Klein, Dana; Jankowski, Mark; Roy, Charlotte L.; Nguyen-Phuc, Hoa; Chen, Da; Neuman-Lee, Lori; Redig, Patrick; Ponder, Julie
Domestic chickens (Gallus gallus domesticus) were exposed to imidacloprid by gavage once daily for 7 consecutive days at 0, 0.03, 0.34, 3.42, 10.25, and 15.5 mg/kg/day (n = 20 per group; 5 6-week-old males, 5 6-week-old females, 5 9-week-old males, and 5 9-week-old females). The severity and duration of neurobehavioral abnormalities were recorded. Components of the innate and adaptive immune system were assessed with 7 standard functional assays. Temporary neurobehavioral abnormalities were observed in a dose-dependent manner, including muscle tremors, ataxia, and depressed mentation. Based upon mean clinical severity scores, the no observed adverse effect level (NOAEL) was 3.42 mg/kg/day, and the lowest observed adverse effect level (LOAEL) was 10.25 mg/kg/ day. The effective dose value for the presence of any neurobehavioral abnormalities in 50% of the test group (ED50) was 4.62 ± 0.98 mg/kg/day. The ED50 for an adjusted score that included both severity and duration of neurobehavioral abnormalities was 11.24 ± 9.33 mg/kg/day. These ED50 values are equivalent to a 1 kg bird ingesting 29 or 70 imidacloprid treated soybean seeds respectively. Immunotoxicity was not documented, possible causes include the assays were insensitive, relevant immune functions were not examined, or imidacloprid is not immunotoxic at this dosing schedule in this species. Neurobehavioral abnormalities were a more sensitive indicator of the sublethal effects of imidacloprid than immunotoxicity.
Holocene Paleofloods And Their Relevance To Flood Mitigation, Risk Assessment, And Policy.
(2020-04) Hefner, Amanda
Paleofloods are past floods that occurred without being recorded by direct hydrological measurement. Paleoflood evidence can tell us about older, and often much larger historic flooding events than those of the instrumental record. For the past 40 years, paleoflood hydrologists have made the argument that geological or botanical flood evidence can help us better understand the true risks of extreme floods. However, because paleoflood studies are typically presented as individual works for single rivers, it is not known how often this kind of work produces information about floods that are equal or larger than the flood-of-record in conventional hydrological gage records. In my research, I created a new synthesis of all available paleoflood case studies on river systems in the U.S. spanning all available proxy records during the Holocene. My synthesis compared the largest paleoflood event in an area against the flood of record reported by the nearest stream gage, and also evaluated the relevance of paleoflood hydrology to natural hazards research. In order to be included in my analysis, studies had to have taken place on a river system in the continental U.S. during the Holocene, and also had to report a variable of flood magnitude. In the strong majority of cases (70%), Holocene paleoflood events are larger than the largest flood as recorded by instrumental river gages. In the most extreme case, a paleoflood event on Elk Creek, SD had a magnitude 12 times larger than the flood of record. While there is great potential for using data from paleoflood studies in flood frequency analyses, paleoflood hydrologists do not have a standard approach to reporting their results. In my review, I will present a list of suggestions for reporting the location, date, and magnitude in future paleoflood studies to comply with new reporting standards outlined in USGS Bulletin 17C.
Increasing transparency in the implications of variability in contaminant partitioning
(2021-11) Brennan, Amanda
Porewater concentrations of contaminants in aquatic sediment (Cfree) are often measured with passive sampling methods (PSM) to quantify the true contaminant activity more accurately. This Cfree correlates more closely with uptake and toxicity in benthic organisms than solid-phase contaminant concentrations (Ctotal) or model predictions of Cfree from Ctotal, and thus represent a better indicator of bioavailability and risk. While sediment managers rely on accurate measures of Cfree to estimate risk, they also rely on Ctotal as the basis for defining and monitoring clean-up goals for restoration and remediation. In real environments, the partitioning of contaminants between Cfree and Ctotal is highly variable among samples collected, even those in close proximity. The variability is due to intractable differences in adsorption capacity among different carbon phases; however, this variability can provide a quantitative basis for converting between Ctotal and Cfree in a stochastic approach. The stochastic approach can be used to estimate the likelihood that Ctotal would exceed a Cfree-based biological threshold in the case in which Cfree was not measured (or vice versa). When the stochastic approach to bioavailability is implemented at the beginning of the risk assessment process, screening-level evaluations can be refined and possibly reduce the number of sediments in which additional testing (e.g. toxicity testing) is required to elucidate risk. This dissertation uses field-collected measurements and statistical modeling to illustrate how PSM-measured Cfree and a stochastic view of contaminant partitioning can provide a more nuanced way of understanding the implications of variability in contaminant partitioning. This view can support more transparency in decision making at contaminated sediment sites.
Resources from "Promoting farm advisor engagement and action toward the improvement of dairy cattle lameness"
(2022) Wynands, Erin; Cramer, Gerard; Cramer Foot Health Lab
Resources and Risk assessments provided to study participants in a lameness Extension project. These resources are associated with the JDS article, "Promoting farm advisor engagement and action toward the improvement of dairy cattle lameness."
Risk assessment of feed ingredients of porcine origin as vehicles for transmission of Porcine Epidemic Diarrhea Virus (PEDV)
(2015) Sampedro, Fernando; Snider, Tim; Bueno, Irene; Bergeron, Justin; Urriola, Pedro E; Davies, Peter R
The objective of this project was to assess the likelihood that feed ingredients of porcine origin may function as vehicles of Porcine Epidemic Diarrhea virus (PEDV) transmission via feed. The scope of the assessment included rendered ingredients, ingredients derived through spray drying porcine blood, and ingredients derived by hydrolyzing porcine tissues. For any feed ingredient, the risk of the release of infective PEDV is a function of: (1) the concentration of PEDV in the raw materials; (2) the virus survival after ingredient processing (3) the survival of virus during post-processing storage and distribution; and 4) the likelihood of post-processing contamination incorporating PEDV into the finished ingredient. No data on PEDV contamination of raw materials were available for the rendering and hydrolyzed protein sources. Estimates of PEDV contamination of liquid plasma were available from industry, based on PCR testing of ingredients over time, and were used in quantitative modeling. The assessments made in this project were constrained by a paucity of specific data on several aspects that are germane to the risk of PEDV transmission in feed ingredients of porcine origin. Available data on thermal inactivation of PEDV indicate that risk of virus surviving the processes of rendering and hydrolysis (peptone production) are negligible. The time and temperature profiles used in spray-drying are much less severe, and therefore, the possibility of virus survival is inherently greater if non-thermal mechanisms are ignored. Overall, currently available data indicate that probability of PEDV surviving the spray-drying process and current commercial storage periods is extremely small. In the course of the project, several data gaps were identified that contributed to the uncertainty. Risk assessment is an iterative process and the findings of this report may be revised in the future if new knowledge becomes available.
Self-reporting of risk pathways and parameter values for foot and mouth disease in slaughter cattle from alternative production systems by Kenyan and Ugandan veterinarians
(2021-08) Adamchick, Julie; Rich, Karl M.; Perez, Andres M.
Countries in which foot and mouth disease (FMD) is endemic may face bans on the export of FMD-susceptible livestock and products because of the associated risk for transmission of FMD virus. Risk assessment is an essential tool for demonstrating the fitness of one’s goods for the international marketplace and for improving animal health. However, it is difficult to obtain the necessary data for such risk assessments in many countries where FMD is present. This study bridged the gaps of traditional participatory and expert elicitation approaches by partnering with veterinarians from the National Veterinary Services of Kenya (n=13) and Uganda (n=10) enrolled in an extended capacity-building program to systematically collect rich, local knowledge in a format appropriate for formal quantitative analysis. Participants mapped risk pathways and quantified variables that determine the risk of infection among cattle at slaughter originating from each of four beef production systems in each country. Findings highlighted that risk processes differ between management systems, that disease and sale are not always independent events, and that events on the risk pathway are influenced by the actions and motivations of value chain actors. The results provide necessary information for evaluating the risk of FMD among cattle pre-harvest in Kenya and Uganda and provide a framework for similar evaluation in other endemic settings.
Supplementary files for an expert-based risk ranking framework for assessing potential pathogens in the live baitfish trade
(2022-05-06) McEachran, Margaret C.; Travis, Dominic A.; Phelps, Nicholas B. D.; Sampedro, Fernando; thom4412@umn.edu; McEachran, Margaret C.; Minnesota Aquatic Invasive Species Research Center
The purpose of this study was to develop a “hazard identification” and ranking tool to identify the pathogens that pose the highest risk to wild fish from the release of live baitfish by recreational anglers in freshwater systems. We developed a screening protocol and semi-quantitative stochastic risk ranking framework by combining published data with expert elicitation (n=25) and applied the framework to identify high-priority pathogens for the bait supply in Minnesota, USA. Normalized scores were developed for seven risk criteria (likelihood of transfer, prevalence in bait supply, likelihood of colonization, current distribution, economic impact if established, ecological impact if established, and host species) to characterize a pathogen’s ability to persist in the bait supply and cause impacts to wild fish species of concern. Of an initial list of 33, 15 potential pathogens met the criteria for inclusion and were evaluated using the semi-quantitative framework. The generalist macroparasite Schizocotyle acheilognathi was identified as presenting highest overall threat to wild Minnesota fish, followed by the microsporidian Ovipleistophora ovariae, and viral hemorrhagic septicemia virus. Our findings contribute to the development of risk-based prevention and surveillance methods in support of front-line managers charged with maintaining both the aquatic sporting industry and sustainable, healthy natural resources in Minnesota. In addition, the ranking framework provides a standardized conceptual framework for prioritizing management as novel disease needs emerge.

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