W3045: Agrochemical Impacts On Human And Environmental Health: Mechanisms And Mitigation
(Multistate Research Project)
W3045: Agrochemical Impacts On Human And Environmental Health: Mechanisms And Mitigation
Duration: 10/01/2015 to 09/30/2020
Statement of Issues and Justification
Issue: By the mid-century, the human population is predicted to reach nine billion. While there will be greater pressure to develop sustainable systems, agrochemical use will remain a cornerstone for protecting crop yield and thereby helping to meet demands for increased food production. Inevitably, a portion of the applied agrochemicals may be lost to the surrounding environment potentially adversely affecting human and environmental health. Thus, assuring sustainable crop production systems and human-environmental protection will pose increasingly difficult challenges. To minimize risks to humans and to ecosystems, environmentally sound crop and public health protection will require keen understanding of traditional as well as emerging approaches for the study of fate and effects of agrochemicals along with sound mitigation strategies. For example, research in the areas of targeted pheromone and natural product research will be essential for minimizing chemical resistance while limiting adverse effects on beneficial insects, amphibians, and soil microflora.
Continuation of the W-2045 multistate research project will enable collaborations that go beyond the scope of any individual state AES or USDA-ARS unit for advancing and transferring science to agricultural, regulatory stakeholders, and the public who require solutions to complex human and environmental health concerns.
Justification: Since chartered in 1956, the W-2045 has provided leadership in identifying agrochemical fate, exposure and health effects, characterizing adverse impacts from agrochemical exposure to cells, organisms, and ecosystems, and putting into practice and advancing mitigation technologies that reduce risks to humans and the environment. Today, the work of W-2045 extends well beyond the western region with involvement from a wide assemblage of USDA-ARS and nationwide state AES land-grant university researchers-extension specialists. W-2045 members effectively integrate information across scales ranging from molecular to landscape levels to address the fate and effects of agrochemicals and emerging organic contaminants in/on human, animal and environmental health. The ability to cross disciplinary boundaries and to adapt different measurement and modeling tools to address complex emerging environmental problems remains essential for improved risk management and risk communication. Cooperating W-2045 researchers represent an array of aligned disciplines in basic and applied biology, toxicology, environmental chemistry, engineering, risk assessment, outreach, and education to address current and emerging human-environmental agrochemical health issues. USDA-ARS facilities in MN, MD and SD and state land grant AES colleges and their affiliate institutions span over the west (AZ, CA, HI, MT, NM, NV, OR, WA), Great Plains (KS), Midwest (IA, IN, MI, MN, OH), east (NY), and southern states (FL, LA). W-2045 research and extension crosses disciplinary boundaries providing key information to state and national public-environmental health regulatory agencies, soil conservation districts, regional agricultural commodity groups, and agrochemical users. The depth of knowledge and strong collaborations among state AES and USDA-ARS scientists provide a unique amalgamation of research and extension capabilities. This on-going collaboration will remain vital to address existing and emerging challenges for characterizing the impact and devising appropriate mitigations for pesticides and other agrochemicals that are for and from agriculture. The emerging challenges in crop protection will require a broader array of genetic tools for investigating more subtle tropic interactions that can have adverse impacts at the organism, population, community, and ecosystem level. W-2045 membership will continue to include researchers investigating emerging issues who will be needed to develop technologies for future agricultural pest control needs.
The value of W-2045 membership is strongly evident today at the national and international levels. W-2045 members from USDA-ARS (MD) and UC-Riverside AES respectively chaired and co-chaired the 2014 International Congress of Pesticide Chemistry (IUPAC) scientific program activities with program support from many W-2045 members. Collaborations built in W-2045 have continually strengthened state AES and ARS involvement in the American Chemical Society Agrochemical Division (AGRO). W-2045 members from ARS MD, UC-Riverside AES, ARS ND, NV AES, MN ARS, MS AES, OR AES, and WA AES serve in official capacities or on executive committees. It is worthy to note, three W-2045 extension specialists and researchers have been recently distinguished as Fellows in the ACS AGRO. As important, a very high percent of ACS AGRO graduate research awards (40% in 2012 alone) came from W-2045 project members in areas of proteomic/bioavailability modeling to land-scale native grass phytoremediation simulations of herbicide runoff. W-2045 OR AES scientists also provide outreach to the public through toll-free and web-based services from the National Pesticide Information Center (NPIC). This information center provides objective, science-based information about pesticides pesticide poisonings, toxicology, and environmental chemistry that enable people to make informed decisions. TOXicology NETwork (EXTOXNET) also housed at Oregon State University remains among one of the most widely used internet sites for those seeking technical information on pesticides and household chemicals. Members also work closely with industry and non-profit associations impacted by agrochemical use such as the US Composting Council, state agricultural crop and animal commissions and commodity groups. In summary, the collaborative and multidisciplinary activities of W-2045 have been singularly effective in communicating to other researchers, governmental agencies, industry, non-profits and the public about the potential impacts of agrochemicals and ideas for mitigation.
Related, Current and Previous Work
Committee members have developed methodologies to assess risks & mitigate impacts of agrochemicals, monitor their environmental fate & transformation, determine adverse impacts from agrochemical exposure to cells, organisms, & ecosystems, & assess/mitigate risk of exposure to humans & non-target organisms. This collaboration has also identified information gaps in agrochemical human & environmental health & served to identify research opportunities for member collaboration.
Assessing Agrochemical Toxicity-Exposure to Humans & Communicating Risks:
Farm workers & their families remain a subpopulation most heavily exposed to agrochemicals (NRC 1993; Curl et al., 2002; Barr et al., 2005; Bradman et al., 2011). W-2045 scientists collaborate with state agencies & commodity groups to monitor exposures of workers to frequently used OP insecticides. The research by CA-Davis for red blood cell acetylcholinesterase (AChE) activity as a biomarker of exposure to OP insecticides has resulted in one of the largest cholinesterase data bases ever assembled for assessing insecticide exposures to farm workers & has significantly improved the accuracy of such tests that have come under scrutiny in the past (Wilson 1996; Wilson 2010). CA-Davis has also assayed the importance of, pyridostigmine (PD), a reversible inhibitor of acetylcholinesterase in human muscle tissue. This work shows that PD when used as a pretreatment can minimize the effects of “nerve gas” on muscle tissue if used in conjunction with the standard treatment of atropine & pralidoximine chloride (2-PAM) (Henderson et al., 2012). Besides OPs, pesticide handlers, agricultural workers including harvesters, bystanders, & consumers are exposed to pesticides by various routes including exposure through home use of products such as foggers & pet flea control products (Krieger; 2001). W-2045 researchers (CA-Riverside) have extensively contributed to toxicology & biomonitoring by developing & evaluating insecticide biomarkers for assessing exposure to flea control products & home pyrethroid foggers (Dyk et al., 2010; Keenan et al., 2010).
Off-target soil fumigant emissions remain a primary source of inhalation exposure to individuals & communities at urban/agricultural interfaces. The combined efforts from W-2045 state AES (UC-Riverside, FL, WA) & USDA-ARS research have advanced & put into practice containment technologies that appreciably reduce off-target fumigant movement while providing efficacious soil-borne pathogen/nematode control (Wang et al., 1997; Gan et al., 1998; Papiernik et al., 1999; Yates et al., 2002; Thomas et al., 2011; Littke et al., 2013). These improvements in soil fumigant retention has led to substantial reduction of state & national no treatment buffer zones preserving production acreage while benefiting growers & protecting human & environmental health. Inhalation exposure concerns, however, are not limited to the parent fumigant; atmospheric transformation products are sometimes more toxic. W-2045 SAE scientists in NV & WA have conducted basic research (Lu et al., 2014) & developed air sampling systems (Woodrow et al., 2014) to measure toxicologically relevant fumigant by-products in air. This research will aid multi-state public health agencies for ascertaining the effectiveness of putative fumigant emission reducing technologies for human health & make available a mechanism for communicating fumigant exposure risks to the community.
The need to continually seek prudent control options while reducing public exposure is exemplified by the recent West Nile virus (WNV) outbreak. Since it was first observed in New York in 1999, the WNV has now spread across the landscape & is endemic. Field research conducted by W-2045 MT scientists in MT, CA, & LA has provided for the first time a comprehensive perspective of human-health risks from ultra-low volume mosquito adulticide applications needed to control the further spread of this vector-borne disease (Preftakes et al., 2011). MT & WA AES collaboration efforts has led & will continue to provide a better understanding of probabilistic risks to humans, especially sensitive subpopulations, leading to efficacious & safe insecticide application strategies, including those to control WNV spread. This research has allowed for outreach to certified pesticide applicators, training for mosquito management districts, as well as traditional training of graduate students & independent undergraduate research.
In developing countries, occupational & residential exposures to pesticide residues present significant risks to human health especially in rural agricultural communities. Farmers frequently lack the education to read pesticide use labels & often do not have access to personal protective clothing. Entire families are often involved in agriculture creating subpopulations that are at higher risk. W-2045 scientists from Oregon State University have partnered with the UN Food & Agricultural Organization with Environnement et Développement du Tiers Monde (ENDA), a West African NGO, in a Global Environmental Facility Pollution Reduction Program funded project with the aim of reducing exposure to farmers & communities along the Niger & Senegal Rivers which traverse much of West Africa. Agriculture monitoring for pesticides in the environment, including food & water, with refined community survey tools provided information on pesticide use practices & human behavior. Risks were communicated & mitigation approaches developed to improve human health for farmers & communities in this region of West Africa (Jepson et al., 2014). More recently, in collaboration with USDA FAS, an Oregon State University W-2045 scientist has hosted a Borlaug Fellow from the Viet Nam National Institute for Food Control, evaluated Ethiopian institutional capacity for monitoring contaminants in food, water, & the environment necessary for assessing human & environmental health risks, & conducted workshops in Algeria & Jordan to provide pesticide regulatory technical assistance for chemical security & safe use of agricultural pesticides in North Africa & the Middle East. This State Department funded program is designed to promote the security of agricultural pesticides in North Africa & the Middle East. One aim of this program is to build North Africa & Middle East partner countries’ institutional capacities for registration & use of agricultural pesticides, & to systematically replace especially dangerous & obsolete pesticides with safer products & sustainable practices to meet relevant international safety standards for agricultural pesticides. This project engages partner countries in an active global network of technology transfer among pesticide researchers, regulators, & standard setting authorities including Egypt, Morocco, Algeria, Jordan, Tunisia & Yemen.
Atmospheric Transport & Fate
Atmospheric transport may serve as an important pathway for pesticide distribution contributing to pesticide contamination at the air & watershed scale. W-2045 research & extension has improved our understanding of how certain land management practices contribute to & possibly accelerate the movement of agrochemical residues into air, forming part of the basis for evolving pesticide regulations. W-2045 USDA-ARS MD scientists in cooperation with University of Florida & National Park Service scientists showed that through air monitoring & model prediction the organochlorine insecticide endosulfan undergoes long range transport by a combination of drift & volatilization processes from areas of high agricultural use to ecologically sensitive areas in Florida. Utilizing the unique properties of the two endosulfan isomers, the contributions of drift versus volatilization to air concentrations observed in the field was characterized (Hapeman et al., 2013). This research has interfaced with recent United Nations provisions that have called for phasing-out this recently classified persistent organic pollutant (POP) in US agriculture.
Transport & Fate on Land Surfaces
Overland & subsurface transport of pesticide residues & organic contaminants from sites of application is of great concern for protection of water quality. USDA-ARS SD field studies have demonstrated greater potential for offsite transport of new & traditional herbicides from eroded upper slopes when compared to depositional lower slope areas. Soil-specific information may be needed to discern the relative importance of interacting soil processes in determining the fate & transport of herbicides & other chemical contaminants in spatially variable landscapes. This comparatively new perspective of onsite specific characteristics that influence pesticide behavior will assist in effective implementation of USDA-NRCS soil conservation & crop protection management plans. Advancing our understanding of land-surface-soil interactions will remain critical for characterizing common surface & groundwater contaminants in the western United States. Concerns also continue over perchlorate, an anthropogenic & naturally-occurring compound that interferes with iodide uptake. Perchlorate concentrations found in groundwater & soils that cannot be fully explained from industry &/or agriculture source contributions (Miller et al., 2006). W-2045 NV project research shows that perchlorate can form on sunlight irradiated surfaces by photooxidation of chloride in the presence of titanium dioxide & nitrate. Chloride photooxidation on low organic arid land surfaces in southwestern states may well represent a major source of perchlorate groundwater pollution impacting agriculture. These recent investigations of land surface topography, soil specific information & sunlight driven reaction mechanisms at the land surface remains under-researched & require further investigation.
Agrochemical Impacts at the Watershed-Level
Nonpoint source pollution due to surface runoff is the main course for water quality impairment of surface streams in the U.S. The impairment may be caused by contamination by pesticides or nutrients. The wide use of pesticides & other agrochemicals in agricultural & urban settings results in their frequent detection in surface waters. Addressing impairment will remain a high priority, especially where pesticides & other agrochemicals in surface water may impact listed species under protection of the Endangered Species Act (ESA). Oregon State experimental station scientists have deployed a lipid-free tubing passive sampling at locations in the Pudding River basin Willamette Valley, OR to continuously assay pesticides in a watershed predominately agricultural & classified as critical habitat for ESA listed salmonid species. The adoption of passive sampling approaches can potentially have broader application in Pacific Northwest states for risk assessment & formulating best management plans (BMPs) in ESA critical habitat regions. The Soil & Water Assessment Tool (SWAT; a USDA environmental fate model) has also been utilized by OR AES researchers & extension specialists to identify hydrologic & landscape characteristics, & land use practices that may affect pesticide surface water loading in watersheds where intensive agriculture occur . This watershed scale modeling approach, integrated with continuous passive sampling & pesticide use practice has proved useful in engaging agricultural producers & their advisors in model refinement- as a platform for evaluating IPM practices & BMPs designed to reduce pesticide surface water loading. This model & monitoring approach has broad implications for agricultural production-land use practices in US watersheds; both improving water quality & allowing for less conservative regulatory strategies.
Pesticides used in residential areas have been shown to contribute to surface water contamination in urban watersheds. UC-Riverside scientists with researchers from UC Davis have monitored the occurrence of current-use insecticides, including all pyrethroids & fipronil, from eight neighborhoods in Sacramento & Orange County, for over two years. Fipronil & its metabolites, as well as bifenthrin, cypermethrin, & some other pyrethroids have been frequently found in residential runoff under dry & wet weather conditions. To further understand the processes contributing to such runoff transport (Jiang et al., 2012). UC-Riverside scientists have further our understanding of pesticide sorption, persistence, & runoff potential from urban hard surfaces such as concrete (Jiang et al., 2012).
Bioavailability & Plant Uptake
With the phasing-out of urban & agricultural organophosphorus (OP) insecticides, greater reliance has been placed on synthetic pyrethroids. The impact on aquatic community structure & health will be associated with their bioavailability. Research by W-2045 California scientists are revealing the importance of sediment aging in regulating agrochemical desorption & using solid phase microextraction (SPME) biomimetic methods that can account for processes & factors governing pyrethroid bioavailability to aquatic macroinvertebrates at environmentally relevant concentrations (Bransislav et al., 2005; Xu et al., 2007; Cui & Gan 2013). As water scarcity is exacerbated by urbanization & climate change, especially in arid & semi-arid regions, treated wastewater is increasingly an attractive alternative source of water for agricultural irrigation. However, many man-made chemicals, including pharmaceutical & personal care products (PPCPs) are present in the finished effluent of wastewater treatment plants. Cal-Riverside AES scientists have evaluated under hydroponic conditions root uptake & plant translocation of commonly occurring PPCPs in vegetables (Dodgen et al., 2013; Wu et al., 2013). Although PPCP dietary uptake appear to be negligible, additional studies are needed under actual field growing conditions to provide a more land-based representation of PPCP accumulation in vegetable crops under realistic cultivation & management conditions.
Remediation of Agrochemical Wastes
Human & environmental agrochemical exposures can occur from improper disposal of unwanted pesticides & rinse water from containers. Inadvertent attention to proper container disposal & rinsates from equipment triggers regulatory actions with consequences for agriculture, land owners, & environmental quality. Advanced oxidation processes (AOPs) have attracted considerable attention due to the potential to generate highly reactive & non-selective hydroxyl radicals that oxidize & mineralize most organic compounds at near diffusion-limited rates. Cornell W-2045 scientists continue to advance AOP technologies to remediate environmental pollutants in water systems using modified Fenton reactions with iron nanomaterials that are environmentally benign (Sun et al., 2011; Sun et al., 2013; Sun et al., 2014). Recent W-2045 nanotechnology advances supported by these AOP kinetic studies are providing opportunities in adopting environmentally safe, cost effective remediation technology for addressing on-site remediation of agrochemicals & organic contaminants at ambient pH.
W-2045 research has advanced understanding of degradation of an array of environmentally persistent legacy organochlorine pesticides & recalcitrant aromatic pollutants. In situ bioremediation employing indigenous & introduced microorganisms by W-2045 FL researchers provide insight for cost effective & efficient means of detoxification leading to mineralization (Gohil et al., 2014). W 2045 HI scientists have also developed immunoassays for more than thirty pesticides, antibiotics, persistent organic pollutants, food contaminants & heavy metals. Recent research is elucidating bioremediation mechanisms that: (i) identify & isolate enzymes & genes responsible for key steps in multiple microbial transformation pathways of aromatic compounds; (ii) identify molecules that can induce catabolic gene expression of specific enzymes; & (iii) use novel microbial consortia for enhanced PAH & PCB degradation (Tittabutr et al., 2011; Seo,et al., 2011; Seo et al., 2013; ).
Determining Adverse Effects from Agrochemical Exposure to Cells, Organisms, & Ecosystems
Linking sub-cellular responses with population-level effects requires a broad understanding of how changes in gene expression or metabolites relate to the organism & important ecological responses that impact growth & reproduction. This information can be used to effectively manage ecological systems & allow proactive rather than reactive strategies for restoring ecosystem health. To date, only a few collaborative efforts have attempted to bridge research at the cellular to ecosystem level examining current & emerging agrochemical impacts. W-2045 members have developed & harnessed a wide array of targeted & global (omics) analytical tools to improve assessment of ecological impacts from agrochemical run-off from concentrated animal feeding operations (CAFOs) & other environmental stressors that include heavy metals, nutrients, & oxygen depletion. Examples include work from KS, Purdue, HI & OR on (i) information at the cellular level to evaluate how organisms respond to environmental stressors; (ii) proteomics & metabolomics approaches investigating declining aquatic invertebrate populations & response of fish to different agrochemical pollutants; (iii) assaying organic contaminant impacts on fish assemblage structure at the molecular level; & (iv) characterization of respiration stress effects from low but environmentally relevant herbicide concentrations. Ecological impacts of agrochemicals on aquatic freshwater ecosystems are also being studied by Purdue scientists integrating predator-prey interactions & disease ecology (Ralston-Hooper 2011; Leet et al., 2012).
Field relevant research for non-target avian species has been elusive, particularly in terms of developing Natural Resource Damage Assessments (NRDAs). W-2045 NV research has developed surrogate avian flight time-behavior models using homing pigeons to assess nonlethal agrochemical exposures & effects (Moye & Pritsos, 2010). This migratory bird model has been employed to assess NRDA migratory bird exposure impacts related to the Deepwater Horizon Oil Spill as well as changes in flight behavior from non-lethal short term avian exposures to methyl mercury. W-2045 Purdue & OR researchers have also characterized certain metabolomes as biomarkers to organic pollutant exposure in migratory birds to better identify the environmental consequences from this large scale oil contamination.
Understanding host plant secondary metabolites and chemotaxonomy for identifying bio-control options for native species and invasive weed control is taking on greater significance. Concerted effort has been directed by MT AES scientists toward understanding the role of small molecule plant signaling hormones in locoweeds. Swainsonine (SWA), an alkaloid that causes severe economic losses through the livestock disease ‘locoism’ is mediated by the presence of the fungal endophytes, Undifilum spp (Vallotton et al., 2012). Induction of certain small molecule plant hormones responsible for pathogen infection and insect herbivory was appreciably altered by the presence or absence of Undifilum. These findings are the first indication that fungal endophytes can influence metabolic pathways in the plant and can have important implications in managing livestock losses. This avenue of plant hormone research is also being currently explored by WA AES scientists to better understand the importance of jasmonic acid and salicylic acid plant hormone signaling for deterring aphid/pea weevil injury in alfalfa production operations.
Emerging Agrochemical Pollutants
National and international monitoring studies are reporting agrochemical contaminants of emerging concern (CECs; e.g., pharmaceuticals, antibiotics, disinfectants, and organic contaminants from packaging/nanomaterials used for humans and in animal production). Another emerging concern is the persistence of pyridine and pyrimidine-carboxylic acid herbicides in compost and can have adverse effects on non-target plant species at concentrations below the analytical detection limit in environmental samples and have been found by W2045 scientists in composts at phytotoxic levels at multiple facilities in the US. W-2045 USDA-ARS MN scientists are comparing assessments of agricultural and urban land use with measured spatial and temporal occurrences of CECs in water and sediment samples from sub-watersheds (Fairbairn et al., 2015). This approach to identify markers of contaminant sources has been sought by policy-makers to aid in developing prudent mitigation strategies to reduce pollution. Cornell W-2045 has also advanced research on rapid an in vitro methods using thin-film solid phase microextraction (TF-SPME) to traditional in-vivo earthworm assays to strengthen our understanding of the bioavailability of hydrophobic agrochemicals and organic contaminants classified as of estrogen-like endocrine disrupting compounds in sediments and soil (Engler and Lemley, 2013). W-2045 multistate involvement among the various USDA-ARS and SAES disciplines will remain critical for identifying, assessing, and developing measurement and mitigation approaches for these emerging agrochemical pollutants.
Effects of Agrochemicals on Pollinators
Pollinator health will remain an on-going US concern among beekeepers, regulatory agencies, & the public. Although there is no consensus about the cause or combination of causes for Colony Collapse Disorder, certain agricultural pesticides that include the nitroguanidine-substituted neonicotinoid insecticides imidacloprid, clothianidin, thiamethoxam, & dinotefuran have been implicated as contributing to colony losses. WA SAE scientists are examining neonicotinoid residues in/on important hive materials (brood wax & stored pollen from bee hives collected in over 150 landscape locations throughout Washington State (citation). This on-going research will increase our understanding of field relevant residue exposures to foraging honey bees that predominately visit vegetation in urban & rural landscapes. Oregon AES researchers are communicating to agricultural producers, public, & the private sector pollinator health best management practices (BMPs) to increase awareness to protect pollinators in urban public-commercial landscapes & in agriculture-forestry. Increased understanding of the use of neonicotinoid insecticides & of the relative contribution of multiple stressors include loss of forage lands, parasites & pathogens, lack of genetic diversity, & poor nutrition will help guide the development of appropriate mitigation strategies.
Monitoring of Agrochemicals in Food
With industry support, W-2045 researchers (LA) have further developed & deployed highly advanced separation & mass spectroscopy methods to assess the presence/absence of organic contaminants in near shore seafood to assure food safety (Xia et al., 2012). In association with MS State health agencies, FDA, & NOAA, organic chemical contaminants in seafood samples were no different than commonplace daily exposures in cooked foods. The outcomes of this multistate effort have been communicated to the public through multistate university extension-outreach. Pesticide dietary exposure & international pesticide maximum residue level (MRL) issues can be a major concern of producers exporting fruits & vegetables to international markets. Developing effective spray management programs will continue to be a challenge especially for producers exporting to countries where vastly different international MRL requirements exist. State AES extension specialists & researchers in OR & WA are working in concert with commercial growers towards optimizing control strategies that reduce possibilities for pesticide resistance while assuring international MRLs are not exceeded. Food safety assays that can quantifiably measure certain neonicotinoid pesticides in fruit juices (Xu et al., 2010), polybrominated diphenyl ethers (Wang et al., 2010) & organochlorine pesticide residues in honey (Wang et al., 2010) have been developed by HI AES researchers that also chemically profile origin. These studies show that honey samples from developing countries contained higher concentrations of total organo-halogenated compounds than those from developed countries.
Relationship of W-2045 to Other Projects
A thorough search of the CRIS system was conducted to determine if the proposed research is being duplicated in any other USDA supported project. This committee & the W-2082 committee (Evaluating the Physical & Biological Availability of Pesticides & Contaminants in Agricultural Ecosystems) both address similar issues of environment contaminants from distinct but complementary perspectives. W-2082, explores the transport of substances in the soil with the aim of developing management tools for the use of agrochemicals that will minimize environmental contamination. The W-2045 committee focuses on agrochemical toxicity, fate-transport, & ways to mitigate agrochemical impacts at the cellular to land-scale to improve human & ecosystem health. Some of our W-2045 colleagues are members for both multistate groups & share relevant information at annual meetings. Participants in W-20 45 have been involved in establishing tolerances of pesticides on specialty crops, a major goal of the IR-4 program.
Identify, develop, and/or validate trace residue analytical methods, immunological procedures, biosassays and biomarkers.
Characterize abiotic and biotic reaction mechanisms, transformation rates, and fate in agricultural and natural ecosystems.
Determine adverse impacts from agrochemical exposure to cells, organisms, and ecosystems.
Develop technologies that estimate and mitigate adverse human and environmental impacts.
MethodsObjective 1: Identify, develop, and/or validate trace residue analytical methods, immunological procedures, and biomarkers Measurement technologies will be optimized with respect to environmental and biological matrices to assess potential agrochemical impacts. Here, research will be forwarded at The Ohio State University, Cornell University, Purdue University, USDA-ARS facilities in Beltsville, Minnesota, and the University of Hawaii. Ohio State University’s Ohio Agricultural Research and Development Center (OARDC) researchers will develop appropriate analytical tools to better characterize agricultural waste management processes and their effects on agrochemical fate and persistence. These researchers will also be engaged in developing bench-scale reactor systems to track the fate of environmentally persistent pyridine and pyrimidine carboxylic acid herbicides from commercial feedstocks, in finished composts and anerobic digestates. This work will include procurement of compost throughout the US for residue analysis and bioassays using sentinel plant species. Trace-level residue analyses will be developed in consultation with herbicide producers and W-2045 members with expertise in this area to track their fate and allow for multistate screening of composts. Biosolids applied to agricultural fields, parks, and other areas represent significant sources of estrogen-like endocrine disrupting compound (EEDC) inputs to soil. Since these compounds often enter the environment via the sewage treatment system, EEDCs have also been detected in substantial quantities in sewage treatment plant sludge, which is commonly applied to agricultural fields. Cornell scientists will continue to develop “green” in vitro bioavailability procedures that employ thin-film solid phase microextraction (TF-SPME) as an alternative to traditional to in vivo Eisenia fetida (earthworms) methods. Cornell researchers will also continue to optimize this new rapid screening in-vitro method for assaying the bioavailability of EEDCs in soils and sediments. Purdue SAES scientists will continue to strengthen understanding of mechanisms of toxicity (MOT) of ionic metals and on metal nanoparticle surfaces and ascertain where these MOT cellular interactions take place and if they are complementary, additive or, can produce a greater overall synergistic toxic response. USDA-ARS Beltsville and Minnesota scientists will continue to characterize the long range atmospheric fate of agrochemical persistent organic pollutants (POPs) and contaminants of emerging concern for mitigation in surface and ground waters. HI AES researchers will build on their existing immunoassay and proteomic capability and focus on identifying and isolating catabolic enzymes and genes for optimizing microbial transformation pathways of current and emerging environmental contaminants. Concerted efforts will be directed to identifying degradation bottlenecks and seeking enzymatic pathways that can lead to total contaminant mineralization. A multistate collaborative air monitoring research project involving NV, CA-Davis, and WA SAEs spear-headed by CA-Riverside is being proposed to bridge the gap between the public view of pesticide analytical detection and levels that assure safety based on risk assessment. Air sampling and analysis will employ pesticide methods published by California Department of Pesticide regulation, UC Davis, UC Riverside, University of Nevada, and Washington State University. Ambient air measured and modelled levels, indoor air inhalation dose, and biomonitoring will be communicated and residents apprised of exposures exceeding those reference doses. Means of communication will also include publications in technical reports as well as in material available widely in the farming communities. Training sessions with farmworkers and spray application personnel will be aimed at raising awareness and progress in adoption of appropriate intervention methods. The anticipated outputs of this multi-state air-biomonitoring collaboration will result in improvement of approaches to risk communication to the public and for risk management officials that deal with the risk for bystander exposures. Objective 2: Characterize abiotic and biotic reaction mechanisms, transformation rates, and fate in agricultural and natural ecosystems Methods for the study of agrochemical transformation (mechanisms and rates) will be developed at the University of Nevada, Cornell University, Oregon State University, Washington State University, Iowa State University, UC-Riverside, Louisiana State University, University of Florida, University of Hawaii, and USDA-ARS locations at Riverside, CA, St. Paul and Morris, MN, and Beltsville, MD. Under controlled laboratory and field investigations, Nevada and Washington State AES researchers will continue to assess occupational and bystander human health risks from inhalation exposure to the agriculturally important pesticides. Anticipated benefits of this collaborative research will aid multi-state public health agencies in: 1) establishing the potential human health consequences from pesticide emissions that include atmospheric breakdown products; 2) ascertain the effectiveness of recent label changes and emission reducing technologies on human health; and 3) make available a mechanism for communicating exposure risks to the community, state and federal public health agencies. Cornell will forward recent advanced oxidation processes (AOPs) successes of heterogeneous Fenton-like reactions that utilize both naturally occurring iron mineral and nano-scale substrate surfaces for the degradation of agrochemicals in both aqueous and sediment systems. Next steps will build on better defining reaction mechanisms for a variety of agrochemicals and optimizing reaction kinetics at neutral pHs for broader US-based field mitigation. Oregon AES extension specialists will continue to explore regional pesticide modeling approaches that incorporate continuous passive sampling monitoring and spatial analysis providing state-local agency-producer stakeholders land use practices forecasting tools for understanding impacts of pesticide and other agrochemical surface water loadings to critical stream habitats. SWAT (Soil and Water Assessment Tool) will be refined to evaluate the relationship between land use, pesticide use practices, climate, and potential for pesticide surface water loading at the watershed scale. Input data, model parameters and/or model processes will be augmented to best simulate changes in land cover/land use, changes in pest management or the implementation of beneficial management practices. Model enhancements will continue to aid IPM and other beneficial management practices to reduce watershed pesticide loading. In addition, model simulations will be used to identify areas within the watershed where the implementation of mitigation measures could have the greatest impact on the reduction of agrochemical loading. OR AES extension specialists will also continue to take a leading role in communicating pollinator health and economically viable best management practices that can reduce pollinator risks from exposure to pesticides while controlling managed honey bee pests and diseases. Efforts from W-2045 researchers in WA will continue to examine the possible pesticide impacts on colony health from pollen collected by foraging bees. IA W-2045 scientists will continue to test new alternative pesticides derived from naturally occurring plant oils to fight the Verroa mite, a honey bee parasite implicated in Colony Collapse Disorder. Montana SAE scientists will explore uncertainties associated with field environmental concentrations and fate of insecticide applications used in vector-borne disease management. This work can advance the use of novel probabilistic approaches for assessing human-health and ecological risks. Mosquito management professionals from abatement districts throughout the US will continue to be reached by presentations and published research results as related to environmental risk and mosquito management strategies. The need for reclaimed water for irrigation in crop producing regions of the western states will continue to increase based on projected water scarcity from climate change. UC-Riverside AES scientists will continue to evaluate man-made chemical exposures from root uptake and plant translocation under realistic cultivation and management conditions. Objective 3: Determine adverse impacts from agrochemical exposure to cells, organisms, and ecosystems Environmental stressors, including pesticides, heavy metals, nutrients, and oxygen depletion, are detrimental to organisms and are a growing global concern with respect to environmental health and quality. W-2045 research in Kansas will continue to generate important information at the cellular level on organism response to changing environmental stress. This information can be used to effectively manage ecological systems and allow proactive rather than reactive strategies for restoring ecosystem health. Montana AES scientists will continue to evaluate the potential impacts to aquatic organisms from agrochemicals using probabilistic ecological risk assessment. This approach will be used to better integrate agrochemical physiochemical information with dissolved organic matter to estimate bioavailability. Modeling approaches that take into account the physiochemical properties of an agrochemical will remain critical in assessing ecological aquatic risks and developing appropriate environmentally relevant mitigation practices. NV SAE scientists in collaboration with WA SAE propose to evaluate the impacts of non-lethal agrochemical/environmental exposures of the neonicotinoid insecticides imidacloprid and clothianidin on the homing pigeon. The in-life objectives will assess effects of neonicotinoid exposure on reproduction, chick survival, and flight behavior. Analytical objectives of this study performed by the WA SAE will assess the uptake and half-life of these neonicotinoid insecticides by liquid chromatography with tandem mass spectroscopy (LC/MS/MS). Output from this project will provide insights into the effects of acute low-dose exposure on pigeon fertility and fetal development that can have implications for migratory avian species. Runoff from lands fertilized with animal manure from concentrated animal feeding operations (CAFOs) will remain a source of hormones to surface water. Purdue AES scientists will continue to evaluate transport of animal hormones and nutrients from land-applied CAFO waste to adjacent waterways in the Midwest to better understand impacts of land-applied CAFO waste on fish populations and communities. This work will include microcosm assessments that will investigate phenotypic alterations and sex-specific gene expression in juvenile fish species and other aquatic test species. Purdue researchers will also extend our understanding of the separate and combined effects of natural and anthropogenic stressors (chemical contaminants, habitat loss) at multiple scales of ecological organization (i.e. individuals to ecosystems). HI AES scientists will advacne test animal proteomic profiling investigations that can shed light on signaling pathways and lung protein cluster development that may be implicated in human acute respiratory distress from agrochemical exposures. Objective 4: Develop technologies that mitigate adverse human and environmental impacts Drawing from W-2045’s multidisciplinary collaborations and expertise, economically viable technologies and management strategies will aid in preventing and/or mitigating potential agrochemical impacts on human and environmental health. Researchers and extension specialists at the Louisiana, Oregon, and Cornell Universities, and USDA ARS laboratories in Beltsville, MA, Riverside, CA, St. Paul, MN, and Morris, MN will work towards this objective in water and land surfaces while assuring the technological transferability to stakeholders (including state safety and health agencies, chemical manufacturers, growers, extension specialists, and others). University of Florida and Washington State University AES scientists will continue to develop novel technologies to reduce atmospheric emissions of fumigants while providing adequate dispersion in the root zone to achieve adequate efficacy. OSU OARDC scientists will test mitigation strategies to reduce the impact of composts contaminated with persistent herbicides. This will include testing soil amendments such as activated carbon, biochar, zeolite and other compounds that adsorb these compounds and may be effective in reducing the phytotoxicity of herbicide contaminated composts and soils.
Measurement of Progress and Results
- The results of W-2045 research will be disseminated to the scientific community through publications in refereed journals, presentations and at national and international meeting venues. State AES and USDA ARS will continue their collaborative involvement at the multi-state, national, and international levels promoting symposia on transport and fate of agrochemicals for and from agricultural ecosystems. Research and extension outputs will be presented to lay stakeholders through trade magazine publications; outreach presentations and materials; pesticide information centers; technical reports to growers, manufacturers, and crop consultants; workshops; online education modules; presentations to state commodity groups, industry groups (e.g., US Composting Council) state crop commissions, local watershed and conservation districts, funding organizations, etc.; presentations at annual field days; presentations to Pest Control Advisors, operators, and staff; and Certified Crop Advisor proficiency testing modules. Members will submit collaborative research proposals assessing and communicating agrochemical risks to humans and environment and mitigation strategies to state and national funding agencies. Outputs will include the development/completion of rapid and sensitive analytical methods for modern-use agrochemicals including fumigants (and their transformation products), adrenergic agonists, herbicides, insecticides used in agriculture and for vector-borne-disease control, neonicotinoid and emerging new classes of systemic sulfoximine insecticides (i.e., sulfoxaflor) in urban settings and agriculture. The development of these methods will also aid in communicating risks to state-federal regulatory agencies, agricultural stakeholders and the general public. Multi-state activities proposed for assessing bystander volatile and semi-volatile insecticide exposure will result in refined methods that will lead to effective communication to the public and for risk management officials. Water-shed level model enhancements will aid IPM and other beneficial management practices to reduce watershed pesticide loading that can adversely impact threatened and endangered salmonids. Aquatic microcosm assessments that will assess phenotypic alterations and sex-specific gene expression in aquatic test species will extend our understanding of the separate and combined effects of natural and anthropogenic stressors (habitat loss, agrochemical contaminants) at multiple scales of ecological organization. Characterizing/profiling specific roles of locoweed plant hormones and secondary metabolites can provide an alternative avenue to traditional weed land management approaches to controlling the livestock losses from locoism. Field relevant neonicotinoid insecticide exposure to homing pigeons can result in refined in-life and analytical procedures that can be extended to assess effects for important US non-target migratory avian species. Because one of our research aims is to provide information about agrochemical efficacy and best management practices, W-2045 researchers will be in direct communication with agrochemical manufacturers and the EPA to offer suggestions for improving product efficacy and developing label recommendations and restrictions to protect human and environmental health. Results will also be available to federal and state regulatory agencies, which may use this information in future decisions regarding agrochemical registration, risks/benefits, tolerances, and restrictions. Products developed in this project include: technologies that benefit agricultural production by minimizing field-edge buffers with improved dispersion in the root zone; water-shed level model enhancements aiding IPM and producers and other pesticide users in evaluating watershed level impacts to aquatic resources under various pesticide use scenarios; cost effective biomimetic approaches that measure environmentally relevant pesticide effe
Outcomes or Projected Impacts
- Outcomes of W-2045 project renewal will be technology deliverables that can be utilized by regulatory agencies, growers, agrochemical manufacturers and applicators, and regional agricultural commodity groups for making prudent pesticide use management and policy decisions. â€¢ Develop technologies in air, water, soil, biosolids, and composts that will aid in mitigating adverse agrochemical impacts to biota (including humans) and environment â€¢ Provide communication-outreach on current and emerging agrochemical concerns to the science community, regulatory agencies, the agricultural industry and public â€¢ Improve communication of agrochemical risks for humans and environment â€¢ Enhance capability of existing regulatory exposure models to reduce bystander risks â€¢ Improve/refine watershed, aquatic organism, and migratory bird models for assessing the impact of agrochemicals on sensitive non-target plant/animal species and for wildlife protection â€¢ Through applied research and outreach, reduce adverse impacts of agrochemical use on pollinators â€¢ Identify new approaches and strategies to reduce pesticide use and address existing and emerging agrochemical concerns
Milestones(0):nes are linked with W-2045 objectives. We believe that this format is more conducive to time-linking accomplishments for a project of this breadth. While each of the objectives can be clearly linked to others, the specific milestones for each W-2045 objective are not necessarily interdependent. Objective 1 a. Develop bench-scale systems (Years 1-3) and joint protocols for trace-level residues determinations of environmentally persistent herbicides in commercial feedstocks and in finished composts (year 1 â€“ 3). Develop technical documents and publications (Years 3-5). Transfer knowledge to grower-state agency agricultural stakeholders (Years 2-5). These bench-scale efforts will be spear-headed by W-2045 OH and involve active collaborations among OR and WA experimental station scientists for providing hyphenated and highly sensitive ultra-low residue methods using GC/MS/MS and LC/MS/MS resources. b. Refine lab and field methods utilizing â€œgreenâ€ sampling procedures to assess agrochemical contaminant concentrations in aquatic water-sediment systems and in refined waste water treatment (Years 1-3). By Year 5, these methodologies will be available for transfer to stakeholders for use by other laboratories. c. Build collaborative capability of immunological procedures, proteomics methods, and biomarker identification (HI and IN Years 1-5). Communicate key outputs and outcomes to academic and agricultural stakeholders (Years 2-5). d. (2015) Joint research proposal submission (CA, NV and WA) for measuring/modeling bystander pesticide inhalation exposure. Objective 2 a. Determine the kinetics of various biotic and abiotic transformations by the end of Year 3. b. Elucidate the various mechanisms of these reactions by the end of Year 4. c. Determine the fate of agrochemicals and their transformation products in controlled micro-mesocom test systems and selected agricultural and natural ecosystems by the end of Year 5. d. Assess the feasibility of using these remediation techniques in realistic settings by the end of Year 5. Objective 3 a. Determine adverse impacts to target and non-target organisms from agrochemical exposure at the cellular and individual levels by the end of Year 2. b. Determine impacts of agrochemical exposure to target and non-target organisms at the community and population levels by the end of Year 4. c. Establish and transfer models for testing the impact of agrochemical exposures on non-target species in ecosystems by the end of Year 5. Objective 4 a. Develop strategies and technologies that mitigate adverse human and environmental impacts from agrochemicals by the end of Year 3. b. Complete field testing of the methodologies developed in Milestone 1 by the end of Year 4. c. Field demonstration of methodologies will be done by the end of Year 5. d. Transfer technology to appropriate stakeholders, including growers, Federal and State agencies, chemical manufacturers, crop consultants, extension personnel, and modelers. This milestone will be achieved by the end of Year 5.
Projected ParticipationView Appendix E: Participation
The results of the research conducted by the W-2045 scientists will be disseminated to a wide range of stakeholders including other scientists, governmental human and environmental health agencies, agricultural agents, producers, manufacturers and the lay public. W-2045 researchers/extension specialists will seek proactive engagement with the above stakeholders to advance and transfer science for agriculture, regulatory stakeholders, and the public who require solutions to complex human and environmental health concerns. A variety of methods will be employed to disseminate this information, depending upon the audience. The research results will be distributed to the scientific community through publications in refereed journals and presentations at local (e.g., departmental), regional, national, and international meetings. Results will be presented to lay stakeholders through trade magazine publications; demonstration tours; outreach presentations and materials; learning centers; technical reports to growers, manufacturers and crop consultants; workshops; online education modules; presentations to state commodity groups; state crop commissions, local watershed and conservation districts, funding organizations etc.; presentation at annual field days; pesticide applicator training certification sessions, and Certified Crop Advisor proficiency testing modules. Toll-free and web-based services through the National Pesticide Information Center (NPIC) will continue to provide outreach to the public sector. This service puts into the hands of the public objective, science-based information about pesticides pesticide poisonings, toxicology, and environmental chemistry. This service together with TOXicology NETwork (EXTOXNET), both maintained at Oregon State University, will continue to be key public resources for communicating the potential of agrochemical impacts on humans and environment.
The Technical Committee is composed of the members who represent the participating experiment stations, state extension services, and USDA ARS laboratories, as well as an Administrative Advisor, and a representative of NIFA. The officers of the Technical Committee will serve for two years each, and be a chairman and a secretary. The chairman of the technical committee coordinates the collaborative research and the annual technical meeting, with consultation from the administrative advisor. The chairman prepares the agenda, presides over the annual meetings and is responsible for preparation of the annual report. The secretary is responsible for recording and distributing the minutes of the technical committee meeting and carrying out duties assigned by the technical committee or administrative advisor. The officers and the immediate past chairman comprise the Executive Committee, which is empowered to act for the Technical Committee between annual meetings.
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