The Knowledge, Practices and Perceptions of Produce Safety by Commercial Aquaponic Growers of Fresh Fruits and Vegetables in Hawaii
Luisa F. Castro, PhD
Hawaii Produce Safety Program Manager, Hawaii Department of Agriculture
International Food Protection Training Institute (IFPTI)Fellowship in Food Protection
Abstract
Food safety in produce growing operations is a critical component of agriculture both domestically and internationally. Aquaponics, as one type of agricultural system, has gained popularity in the past 20 years, but due to its novelty, food safety and proper harvesting procedures have only recently begun to be addressed for aquaponic growers (Hollyer et al., 2009). This survey is the first effort to study aquaponics in Hawaii and provides information that can inform policy, research, and education efforts regarding aquaponics as it evolves into a mainstream form of agriculture. This study surveyed commercial aquaponic growers of fruits and vegetables in Hawaii to assess the knowledge, practices, and perceptions of on-farm food safety. Growers typically raise fish and a variety of leafy green vegetables, herbs, and fruiting crops in outdoor systems where fish are separated from the crops being grown. Seven of the nine growers surveyed are not washing their produce before it goes to market; about half are testing water for microbial pathogens. Most growers are dealing with wildlife, insects, and pest intrusion. While growers are using many good practices, the results indicate that some practices used may need to be re-evaluated. Most growers have taken some sort of food safety training. However, when asked if they have a GAP certification from a third-party audit, most do not. Growers, while exempt from the FSMA Produce Safety Rule (PSR), do not feel adequately educated about the PSR and perceive barriers to preventive practices. Additional outreach is needed to evaluate and communicate good agricultural practices within the field.
Keywords: aquaponics, Produce Safety Rule, GAP certification, food safety
The Knowledge, Practices, and Perceptions of Food Safety by Commercial Aquaponic Growers of Fresh Fruits and Vegetables in Hawaii
Background
Aquaponics is the mutually beneficial integration of hydroponics (soilless systems for crop production) and aquaculture (aquatic animal farming) to simultaneously produce plant and animal products (Love, Fry, Li, Hill, Genello, Semmens, & Thompson, 2015). In an aquaponic system, aquatic animals excrete waste, bacteria convert the waste into nutrients, and plants remove the nutrients and improve water quality for the aquatic animals (Rakocy, Bailey, Shultz, & Danaher, 2011). This combination of animals and plants encourages many growers to view this growing method as a viable solution for sustainable aquaculture, organic crop production, and water consumption. The North America aquaponics market was reportedly worth $233 million in 2018 and is estimated to reach $424 million by 2023 (Market Research Future, 2018). There were 257 commercial aquaponic producers in the U.S. surveyed by Love, Fry et al. (2015). These producers included hobbyists, educators and commercial producers engaging in this food production method.
Commercial aquaponics production exists primarily in controlled environments, such as greenhouses or outdoor locations with favorable climates, using methods and equipment that draw from both the hydroponics and aquaculture industries. Fish are raised in tanks with hoses connecting the fish tanks to the grow beds containing the crops. The hoses allow water and fish effluent to flow into the grow beds after being filtered for solid removal. The fish waste and uneaten foods are broken down into ammonia (NH3), nitrite and nitrates by beneficial bacteria while plant roots in the grow beds take nutrients from the fish waste and filter the water, which is then cycled back into the fish tank (Short, Yue, Anderson, Russell, & Phelps, 2017; Sirsat & Neal, 2013). This blending of aquaculture and hydroponics to recycle both water and nutrients can result in an efficient use of resources but can also raise concerns about food safety (Fox et al., 2012).
On February 26, 2018 a chain of events prompted the Hawaii Department of Health (HDOH) to shut down all aquaponic operators from selling produce for human consumption. According to Hawaii Administrative Rule Chapter 11, Sanitation, §11-11-8, (1981), a regulation which was last modified and adopted before aquaponic farms had ever appeared in Hawaii, “It shall be unlawful to offer for sale or to sell for human consumption watercress, lettuce, and other vegetables ordinarily eaten raw which are grown in areas subjected to contamination from water used in irrigation or from animals” (HDOH, 1981, p.115). In a statement made by Peter Oshiro, HDOH Sanitation Branch Manager at the time of the shutdown, there is not enough research on aquaponics to understand the food safety of this growing method (Scarbrough, 2018). Although HDOH is now repealing the outdated rule (Hawaii Department of Health, 2018), this lack of information about aquaponic systems by a state regulatory agency and the impact closures would have on aquaponic growers throughout the state was a serious concern.
The Food Safety Modernization Act (FSMA) Produce Safety Rule (PSR) has brought attention to the need to develop guidelines for growers, using a holistic approach to ensure safety of the fruit and vegetable food supply. Education about proper fresh produce handling from farm to fork has been shown to prevent contamination on the farm and within retail settings (Lynch, Tauxe, & Hedberg, 2009). In this regard, the national Aquaponics Association is trying to educate the public and food safety regulators about the inherent safety of aquaponically grown food (Aquaponics Association, 2018). The researcher hopes to develop outreach and education for growers to learn about good agricultural practices (GAPs) and the FSMA PSR. However, gaps exist in our knowledge of who is implementing GAPs or has an understanding of the FSMA PSR. This study was conducted to fill this research gap by documenting the production methods, produce safety practices, and perceptions of aquaponic growers in the state of Hawaii via one-on-one interviews.
Problem Statement
Little research has addressed the produce safety knowledge, education and practices used by aquaponic growers selling produce commercially in Hawaii.
Research Questions
The following research questions guided this exploratory study:
Research Question 1: What is the food safety knowledge and perceptions among commercial aquaponic growers in the State of Hawaii?
Research Question 2: How does commercial aquaponic growers’ knowledge and perceptions toward food safety influence their food safety practices?
Research Question 3: What are the preferred learning modes and information resources on food safety by commercial aquaponic growers in the State of Hawaii?
Methodology
Telephone interviews were conducted from October to December 2018. Prior to the start of the interviews, participants were read their rights as volunteers in the study and assured of their anonymity. The interviews were recorded to enable the interviewer to give each participant full attention during the interview and avoid the need to take notes. Participant permission to be recorded was also requested prior to the start of the interview.
The list of commercial growers was found by using a directory kept by the Hawaii Department of Agriculture’s Aquaculture & Livestock Support Services. Forty-two closed- and open-ended questions were developed using the Aquaponic Association’s Provisional GAP Audit and the Quality Certification Services Aquaponics GAPs Food Safety Standards to capture information about the knowledge, practices, and perceptions of commercial aquaponic growers about food safety via semi-structured interviews. Quantitative and qualitative data were collected concurrently. Questions asked during the interview gathered information regarding: 1) general farm characteristics; 2) knowledge about produce safety and experience with GAPs certification and the PSR; 3) GAP practices in their operations; 4) perceptions about the advantages and challenges of following produce safety and GAPs; and 5) preferences in learning styles and information delivery methods.
The interviews were audio recorded, transcribed into text files and coded for conceptual categories using content analysis as the research method. Content analysis is one of the most commonly used techniques of qualitative analysis for exploring and understanding the underlying meaning of messages in speech and text (Zhang & Wildemuth, 2017). The researcher developed the codes relying on the Aquaponic Association’s Provisional GAP Audit and the Quality Certification Services Aquaponics GAPs Food Safety Standards. MAXQDA, a software application, was used to organize and analyze the data.
Results
Survey Responses
A total of nine commercial aquaponic growers agreed to be interviewed out of 15 who had been contacted to participate in this study. The duration of the interviews ranged from 45 to 70 minutes, with an average time of 60 minutes. There were two growers from Hawaii island, two from Maui, and five from Oahu.
Grower Background
Growers were asked a series of questions about their farming operation. In general, there are three primary aquaponic methods for plant production: floating raft, nutrient film technique, and media-filled beds. All the growers in this study use systems where fish are separated from the crops being grown, with five growers using floating rafts in deep water, two using a nutrient film technique (horizontal irrigated trays or gutter planters), and two using a combination of growing methods (Table 1). No two growers used the exact same filtration system to filter the fish effluent; however, all used some kind of mechanical and biological/chemical filtration technique.
The majority (n=7) of growers have been growing commercially using an aquaponic system between 5-9 years. Only three growers stated that their buyers are requesting that they be GAP certified. Four growers have between 1-3 employees; two have 4-6 employees; one has more than seven employees; one has no employees; and one has volunteers/interns. These aquaponic growers raise a diverse mix of fresh produce. The most frequently raised crops are lettuce varieties (n=8); green onions (n=4); and herbs (n=4). Average produce sales in the last three years revealed five growers making <$25K; three making between $25K-$250K; none making between $250K-$500K; and one making sales over $500K. Of those making <$25K, four were anticipating growing their operations and increasing their markets to earn greater profits in 2019.
Table 1
Knowledge About Produce Safety
Most of the growers (n=7) have taken a food safety training (e.g., HACCP, ServSafe). However, when asked if they have a GAP certification from a third-party audit, five participants have never been GAP certified, three have been certified in the past but are not current with their certification, and only one grower is currently certified. When asked if they have determined if they are exempt, qualified exempt, or covered by the FSMA PSR, five growers confirmed that they had determined their status while the other four expressed not knowing which category they fell under.
Good Agricultural Practices
The majority (n=7) of growers use municipal water as their source, one uses a rainwater catchment system, and another sources water from their own well. Eight of the nine growers do not use UV or ozone to treat the effluent water (water from the fish tanks) prior to it entering the plant growing system. Two growers were adamant about not treating the effluent water because they don’t want to kill the beneficial bacteria in the system. When asked how they know if their water is free of any microbial contamination, five growers said they send water samples to be tested for microbial pathogens on a regular basis, while four do not.
All the growers described protocols to prevent effluent water coming into contact with the edible portion of the crop, including cutting the crop that is growing above the raft or media beds, thus avoiding any splashing of water from below the raft onto the edible portion of the crop. Growers stated they are aware that they should not be touching the raft or the water underneath the raft during harvesting or touching the root system or growing cup when harvesting.
The majority of growers maintain their aquaponic systems outdoors, with only one housing the system both outdoors and in greenhouses. Being open to the environment, growers have to manage wildlife, insect and pest intrusion. The majority of growers reported dealing with rats, birds, slugs and snails. All mentioned having raised beds as an effective management strategy for deterring four-legged wildlife (e.g., feral pigs) from eating their crops. To manage rats, they use traps and poison bait stations around the perimeter of their systems. To manage birds, many use netting over their beds or hang flashy objects that scare birds away (e.g., CDs hanging from fishing lines). Slug and snail poison, gravel groundcover, and growing bed posts wrapped in copper are also methods growers identified as management strategies against gastropods.
Growers were asked personal hygiene questions including if bare hands or gloves are used when harvesting produce. Seven of the nine growers allow bare hands while two require gloves to be worn during harvesting activities. Several growers mentioned having gloves available for use in case of cuts and injuries that would cover the bandaged hand. Four growers confirmed providing formal training on personal health and hygiene to their employees upon being hired as part of their orientation while four others conduct informal training throughout the year by reminding employees of the importance of practicing good hygiene. All growers confirmed having toilet facilities at their operations. Because some of the growers (n=5) live on the properties where they run their aquaponic operations, the toilet facilities are in their homes. Most growers (n=8) stated that they and their workers are required to wash their hands before handling the produce and have washing facilities available for this task.
Currently, all the growers harvest their produce with tools that are regularly cleaned and/or sanitized. Seven growers harvest the produce and inspect thoroughly for damage before placing the produce cleaned and sanitized harvest bins or into plastic bags. The produce is not washed prior to being delivered or picked up by their buyers. However, two growers go through an extensive process of washing, cooling, drying and packaging the produce before delivery. When asked what the procedure is for produce that comes in contact with blood, animal feces, chemicals or other contaminants, the majority of the growers (n=8) stated they have not had these issues, but four growers stated they would throw out their crop if it became contaminated with any feces and two felt that their thorough washing process would remove the contamination.
Perceptions and Learning Preferences
All the growers (n=9) thought produce safety and GAPs are necessary and an important part of their aquaculture operation. Growers indicated having a responsibility to avoid making their customers sick, to avoid ruining the aquaculture industry by causing an outbreak, to contribute to the health and well-being of their customers by growing a safe and high-quality product, and to change the misconception that growing in fish effluent is dangerous. In terms of barriers toward adopting GAPs, six growers indicated that there is a lack of knowledge on their part in understanding the difference in what they need to do to comply with a voluntary third-party audit versus complying with the mandatory PSR requirements. They also felt that there is a misunderstanding about the safety of aquaponic operations by produce buyers and government regulators who require aquaponic systems to comply with the same produce safety requirements as soil-based systems. The cost of complying with the PSR or a GAP certification is another barrier mentioned by five growers — views that are supported by a recent study on Estimated Costs for Fruit and Vegetable Producers to Comply with the Food Safety Modernization Act’s Produce Rule (Bovay, Ferrier, & Zhen, 2018).
One-on-one coaching is the primary method growers (n=6) requested for learning about produce safety and GAPs, followed by webinars (n=4) and online access to experts and information (n=2). Growers want to learn how to do the right thing but without the fear of getting penalized by an inspection or an audit.
Conclusions
Although most growers reported produce safety goals and implementing practices that mirror a general understanding of GAPs, half of the participants reported varying awareness of sources of contamination and practices to prevent or control them. Despite some awareness, most do not feel adequately educated about the PSR and perceive barriers to adopting many of the prevention practices. There is an opportunity for outreach efforts to both support the goals of the aquaponic growers and encourage the adoption of produce safety through greater understanding of the microbial risks to fresh and fresh-cut produce; practices that can prevent contamination; dealing with the economic feasibility of adopting these practices; and preparedness for a contamination event.
Recommendations
A larger, more rigorous study that measures the potential produce safety risks throughout Hawaii should be conducted. Similar studies could be conducted in other states with commercial aquaponic growers.
One-on-one training programs could be established through collaboration between federal, state, and local regulatory agencies and also industry and academia to continue teaching about risk-based best practices to support enhanced produce safety in commercial aquaponic operations.
Outreach activities should involve explaining the differences and similarities between GAP certification and the PSR requirements to help clarify the two initiatives.
Acknowledgements
I offer my sincere gratitude to the International Food Protection Institute (IFPTI) for this invaluable learning experience and opportunity to participate in Cohort VII. I am also grateful to the IFPTI educators, subject matter expert Dr. Paul Dezendorf, and especially my mentor, Katherine Fedder, for her guidance, encouragement and input throughout my project and the entire Fellowship. I would like to sincerely thank the nine participants who trusted me in gathering their knowledge, practices, and perceptions as part of this research. And lastly, I want to give a big thank you to all of the Fellows in Cohort VII for making this such an exceptional experience.
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