Learn more about the research being conducted at SCCAHS!

Extent of Agricultural Pesticide Applications in Florida Using Best Practices

Gregory Glass, Ph.D. Principal Investigator

University of Florida, Institute OF Food and Agricultural Sciences (IFAS)

Project Summary: Although agriculture represents a key industry in Florida, little, recent information is available on the potential exposure for workers from various herbicides and pesticides that are needed to grow commercial food crops. We propose to develop estimates of the potential site-specific environmental exposures that should be expected, based on geographic extents of specific crops, daily local temperature and precipitation regimes when ‘best practices’ are applied to the use of important pesticides and herbicides.

We will use historical (2009) data on state-wide pesticide applications for initial comparisons with the model that use weather patterns during the growing seasons. Historical distributions of selected crops and temperature regimes will be established using high and moderate resolution remotely sensed (RS) imagery and classification algorithms to identify the locations and extents of various crops. Time series analyses of the RS imagery will be used to establish the relationship between modeled phenology and spatial texture and patterns in croplands. We will also use University of Florida 12 agricultural research sites located throughout the state to confirm calibration both of the crop type signatures and the timing and impacts of herbicide/pesticide applications on resulting remotely sensed imagery.

In year 2, we will extend the analysis to the present time (2016) and incorporate additional crops and pesticides based on reported worker exposures to currently applied herbicides and pesticides.

Relevance: The amount, timing and geographic extents of various herbicide/pesticide applications within Florida are unknown making it difficult to establish a baseline of worker exposures even when the treatments are appropriately applied. We propose to use high and moderate resolution remotely sensed imagery to identify the geographic extent of various crops, their growth rates and amounts of pesticide usage expected.

Occupational Health and Safety Surveillance of Gulf Seafood Workers

Andrew S. Kane, Ph.D., Principal Investigator

University of Florida, Department of Environmental and Global Health

Project Summary: Commercial ocean fishing is one of the most dangerous occupations in the world. Workplace-related illnesses, injuries, and deaths are not uncommon for commercial seafood workers, and many of these adverse outcomes are avoidable in this mostly self-employed uninsured, hardworking workforce that feeds our nation. This surveillance research project will assess the current status of commercial fishery worker safety in the southeastern US, focusing on the coastal Gulf of Mexico workforce in Florida and Alabama.

In collaboration with our community partners, we will develop, validate and implement an in-person questionnaire to discern fishery subsector-specific hazards and adverse outcomes associated with occupational injuries, illnesses, and mortalities in the region. Study outcomes will generate meaningful data to represent this largely self-employed and uninsured workforce, and provide feedback to these workers to stimulate awareness and support empowerment for personal, work-related health and safety. Research to Practice (r2p) using findings from this surveillance study will include the development of culturally-relevant outreach and hazard interventions for Gulf coastal communities to provide meaningful acquisition of safety knowledge and skills, and approaches for self-oversight to reduce occupational injuries, illnesses, and deaths. As such, specific aims for the proposed efforts represent T0 (surveillance) to T2 (intervention and evaluation) phase contributions in translational public health research and include: (1) surveillance to discern occupational hazards and risk factors, history of injuries, and knowledge of co-worker deaths for workers engaged in multiple fishery subsectors along the Gulf coast of Florida and Alabama, and (2) development and assessment of potential intervention(s) to address risk factors associated with specific hazards and negative health outcomes in the different fishery subsectors in the project study region.

Relevance: This project addresses critical gaps in our understanding of occupational and hazards and risk factors for Gulf seafood workers. Academic, extension and community partnership efforts will yield critical data to discern risks factors and adverse outcomes for different fishery subsectors and geographic regions provide direct feedback to seafood workers, raise personal safety awareness, and extend networking capacity.

PISCA: Pesticide & Heat Stress Education for Latino Farmworkers that is Culturally Appropriate

Joseph G. Grzywacz, Ph.D. PISCA Project Principal Investigator:

Antonio Tovar-Aguilar:

Florida State University, Department of Family & Child Science

Project Summary: Farmworkers, the majority of whom are Latino immigrants from Mexico, experience elevated rates of occupational injury and illness. Chronic low-dose exposure to pesticides and extreme heat and humidity are major sources of poor occupational health outcomes. Recent revisions to the EPA’s Worker Protection Standard (WPS-r) and growing concern over heat-related illness (HRI) necessitate the creation of safety education curricula that to minimize pesticide exposure and the deleterious effects of exposure to heat and humidity. Use of community health workers or “promotoras de Salud”(promotoras) is common in farmworker occupational health, but few WPS or HRI curricula have been developed for dissemination by promotoras, and there is scant evidence that promotoras are equally effective as “professional educators” who often have college degrees or highly specialized training in the cognate material.

The goal of this project is to reduce pesticide- and heat-related poor health outcomes among Latino farmworkers. We will achieve this goal through a community-advocate-university partnership that will: (1) Create reproducible, culturally- and contextually-appropriate curricula for Latino farmworkers targeting pesticide exposure (suitable for meeting employer requirements under the revised WPS) and HRI, (2) Determine the effectiveness of the developed pesticide and HRI curricula implemented by professional educators in promoting advocated safety behaviors, and (3) Identify the comparative effectiveness of a promotora-based implementation of developed curricula relative to the use of professional educators. This 5-year project will be undertaken in three phases. Phase one is an intervention with farmworkers (n=125) to determine the effectiveness of WPS-r and HRI curricula that will be developed from existing materials. Phase two uses a randomized attention control placebo design (n=325) to determine if our WPS-r curricula performs better than the EPA’s curricula. Phase 3 deploys the curricula to a large cohort of farmworkers (n=400) using a promotora model: collected data will determine the comparative effectiveness of promotoras relative to professional educators.

Relevance: This project develops and tests if safety education materials targeting pesticide exposure and heat-related illness produce changes in safety behaviors among Latino farmworkers. Pesticide exposure and heat illness are major sources of poor occupational health in this vulnerable worker group. Effective safety education programs are necessary to protect farmworker occupational health.

Heat Stress and Biomarkers of Renal Disease

Linda McCauley, Ph.D., Principal Investigator

Emory University, School of Nursing

Project Summary: Recently there has been a marked increase in occurrence of Chronic Kidney Disease (CKD) in agricultural workers in Mesoamerica. The potential mechanism for this increase remains elusive; it may be associated with working in hot environments causing recurrent dehydration leading to decreased renal blood flow, high demands on tubular reabsorption, and increased levels of uric acid or possible activation of the fructokinase pathway. These underlying processes may result in chronic tubular injury and fibrosis.

In this study we will measure physiological indicators of heat-related illness (HRI) in farmworker populations in Florida, incorporating a metabolomics approach to enhance understanding of pathways through which perturbation of renal function occurs. We propose to determine if biomarkers of renal damage shown in Mesoamericans are also present among farmworkers residing in the U.S. that immigrated from Mexico to work in agriculture. We will recruit 70 agricultural workers in Pierson, Florida who are between 18 and 54 years of age, as well as 30 individuals of similar heritage who are not working in heat-intensive agricultural work such as mushroom facilities, packing houses, or hotel workers.

In this exploratory work, we propose to 1) characterize the occupational environment of these workers including work practices, workplace heat exposure and work intensity; 2) characterize the physiologic profile of these workers including body anthropometrics, dehydration, and self-reported heat­related illness symptoms; 3) determine if biomarkers indicating kidney injury are present (kidney injury molecule ­ 1 (KIM-1), Beta-2 microglobulin (B2M), neutrophil gelatinase-associated lipocalin (NGAL), elevated blood urea nitrogen (BUN), creatinine, uric acid, uromodulin, and decreased glomerular filtration rate (GFR)) and if the presence and levels of these biomarkers in agricultural workers differ from controls who are not employed in agriculture; and 4) use nontargeted metabolomics analysis of blood plasma to explore the molecular mechanisms of renal dysfunction associated with occupational heat exposure.

This study will be the first to document the extent of association between heat exposure and CKD in a migrant farmworker population in the US. This study uses an innovative metabolomics analysis to describe possible metabolic pathways affected by heat exposure.

Relevance: Rising global temperatures have resulted in increases in health hazards for populations who work in hot environments, such as agricultural farmworkers. Chronic Kidney Disease is an epidemic in the Mesoamerican region and is thought to be related to excessive heat exposure, high work intensity, and recurrent dehydration. This study will provide important information on the existence of kidney injury biomarkers to aid in the prevention of kidney injury in the U.S. farmworker population.