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Abstract

Introduction Aquaponics systems have become increasingly popular today. It connects recirculating aquaculture with hydroponics to use nutrient waste from fish production as an input to plant production (Radosavljević et al., 2014). It is a relatively new idea about the use of same water in order to growth fish and plants in a single system. Aquaponics can provide both fish as a source of animal protein and fresh vegetables, culinary and medicinal herbs as a source of minerals and vitamins to populations where water or fertilizer resources are limited (Kotzen and Appelbaum, 2010) with a minimum of environmental contamination. The main principals of aquaponics are the use waste plant and animal material for fish nutrition, which fish convert into protein. Then, the waste from fish is used by plants as a source of nutrients and the water recirculate back to the fish tank (Rakocy et al., 2006). Undoubtedly, this technique has many potential benefits. It is designated as enclosed recirculating integrated system so possess lower environmental impact in comparison with conventional agricultural systems. Lennard (2006) showed that nitrate accumulation was reduced by 97% in aquaponics in comparison to common recirculating aquaculture systems. Also, the amount of water is small in comparison with regular systems for fish and plant production and about 98% of water is recycled in aquaponic systems (Al-Hafedh et al., 2008). Aquaponics also enables fish and plants to be reared together in relatively small amount of space. On the other hand, it should have in mind that there are not enough scientific data regarding best practice for aquaponics in order to ensure food safety. Such data will be useful as a base of regulations and recommendations for aquaponics production. This paper will summarize currently available food safety data and discuss potential food safety risks that may be associated with aquaponics. Food safety risks in aquaponics Foodborne transmission of pathogenic microorganisms from contaminated food has been recognized as an important hazard for human health in the past few decades and pathogenic strains of aquatic bacteria have long been considered as serious zoonotic hazards. Without exception, food safety risks are present in integrated food production systems including aquaponics. Additional problem is the fact that many of these risks are still unknown or are not enough researched. There is still little knowledge about foodborne diseases in aquaponics. Proximity of fish culture water to edible plant culture represents a specific concern in aquaponics. Fish is generally not regards as a food safety threat in aquaponics but potential for survival and growth of potential pathogenic microorganisms is unknown so the evaluation of this assumption is necessary. Listeria monocytogenes, Salmonella spp., Shiga-toxin producing E. coli, Vibrio spp., Aeromonas spp., Streptococcus spp., Erysipelothrix rhusiopathiae, Shigella spp., Campylobacter spp., Pleisomonal shigelloides, Edwardsiella tarda, Cryptosporidium and other could be potential food safety microbiological threats in aquaponics (Ljubojević et al., 2016). Pathogens can be introduced to fish as final products by hands or direct water contact. From the point of food safety it should emphasized that water can be a source of many pathogens including E. coli, Salmonella spp., Vibrio cholera, Shigella spp. Besides that, parasites such as Cryptosporidium, Girdia lamblia and also viruses so the origin of water used in aquaponics is very important for the safety of final products, both fish and plants. Contamination with some of the mentioned microorganisms can lead to foodborne diseases in humans. Furthermore feed intended for fish could be a source of bacterial pathogens, micotoxins or veterinary drugs. Furthermore, there is very little or no data regarding efficacy of current control measures to prevent the presence of foodborne pathogens in aquaponics. Small aquaponics settings in urban areas can also be owned by non-profit oganisations or small size enterprises that do not inevitably have the knowledge regarding food safety issues. The need for guidance with regards to hazard analysis, implementation of preventive measures and regulatory compliance is indubitable. There is also need to point toward the present difficulty in the aquacuponics management and to show the possible ecological and economical impacts. Risk management systems Aquaponics systems are commonly in vicinity of humans and that can be a serious concern for public health. Food safety begins on the farm or in this case, in aquaponic systems. New methods are developed in order to detect infection or contamination in fish, plants and their environment. Various biosecurity measures that prevent transfer of pathogens among fish and environment may be implemented. Sometimes the absence of clinical symptoms does not mean the absence of pathogens and it should have in mind that such carriers could help in amplifications of microorganisms. In the most cases, producers are not aware that such microorganisms could be present in aquaponic systems. Producers should be encouraged to implement preventive and control measures and risk management systems in order to prevent the occurrence of pathogens in aquaponic systems. Good agricultural practice, good hygiene practice, good management practices and management of wastes, feed, water and potential vectors are some of the current strategies. Conclusions Because fish meat can be potential reservoir of food borne pathogens, the necessity for education of people regarding good hygienic practices should be highlighted. Education of food handlers is also significant in order to decrease the potential risk regarding food borne diseases. Moreover, the education of owners of aquaponic systems, veterinarians, public, and health practitioners is very important. Monitoring and recording of occurrence should be the main operations in the upcoming years which should moot questions of how to make better and put into actions the established directives.
676
FOOD SAFETY HAZARDS RELATED TO FISH PRODUCED IN AQUAPONICS
D. Ljubojević1*, M. Pelić1, V. Radosavljević2 and M. Ćirković1
1Scientic Veterinary Institute “Novi Sad”, Rumenački put 20, 21000 Novi Sad (Republic of Serbia),
2Department of sh diseases, Institute of Veterinary Medicine of Serbia, Vojvode Toze 4, 11000 Belgrade (Republic
of Serbia)
E-mail: dragana@niv.ns.ac.rs
Introduction
Aquaponics systems have become increasingly popular today. It connects recirculating aquaculture with hydroponics to
use nutrient waste from sh production as an input to plant production (Radosavljević et al., 2014). It is a relatively new
idea about the use of same water in order to growth sh and plants in a single system. Aquaponics can provide both sh
as a source of animal protein and fresh vegetables, culinary and medicinal herbs as a source of minerals and vitamins to
populations where water or fertilizer resources are limited (Kotzen and Appelbaum, 2010) with a minimum of environmental
contamination. The main principals of aquaponics are the use waste plant and animal material for sh nutrition, which sh
convert into protein. Then, the waste from sh is used by plants as a source of nutrients and the water recirculate back to
the sh tank (Rakocy et al., 2006). Undoubtedly, this technique has many potential benets. It is designated as enclosed
recirculating integrated system so possess lower environmental impact in comparison with conventional agricultural
systems. Lennard (2006) showed that nitrate accumulation was reduced by 97% in aquaponics in comparison to common
recirculating aquaculture systems. Also, the amount of water is small in comparison with regular systems for sh and plant
production and about 98% of water is recycled in aquaponic systems (Al-Hafedh et al., 2008). Aquaponics also enables sh
and plants to be reared together in relatively small amount of space. On the other hand, it should have in mind that there are
not enough scientic data regarding best practice for aquaponics in order to ensure food safety. Such data will be useful as
a base of regulations and recommendations for aquaponics production. This paper will summarize currently available food
safety data and discuss potential food safety risks that may be associated with aquaponics.
Food Safety Risks In Aquaponics
Foodborne transmission of pathogenic microorganisms from contaminated food has been recognized as an important
hazard for human health in the past few decades and pathogenic strains of aquatic bacteria have long been considered as
serious zoonotic hazards. Without exception, food safety risks are present in integrated food production systems including
aquaponics. Additional problem is the fact that many of these risks are still unknown or are not enough researched. There
is still little knowledge about foodborne diseases in aquaponics. Proximity of sh culture water to edible plant culture
represents a specic concern in aquaponics. Fish is generally not regards as a food safety threat in aquaponics but potential
for survival and growth of potential pathogenic microorganisms is unknown so the evaluation of this assumption is necessary.
Listeria monocytogenes, Salmonella spp., Shiga-toxin producing E. coli, Vibrio spp., Aeromonas spp., Streptococcus
spp., Erysipelothrix rhusiopathiae, Shigella spp., Campylobacter spp., Pleisomonal shigelloides, Edwardsiella tarda,
Cryptosporidium and other could be potential food safety microbiological threats in aquaponics (Ljubojević et al., 2016).
Pathogens can be introduced to sh as nal products by hands or direct water contact. From the point of food safety it
should emphasized that water can be a source of many pathogens including E. coli, Salmonella spp., Vibrio cholera,
Shigella spp. Besides that, parasites such as Cryptosporidium, Girdia lamblia and also viruses so the origin of water used in
aquaponics is very important for the safety of nal products, both sh and plants. Contamination with some of the mentioned
microorganisms can lead to foodborne diseases in humans. Furthermore feed intended for sh could be a source of bacterial
pathogens, micotoxins or veterinary drugs. Furthermore, there is very little or no data regarding efcacy of current control
measures to prevent the presence of foodborne pathogens in aquaponics. Small aquaponics settings in urban areas can also
be owned by non-prot oganisations or small size enterprises that do not inevitably have the knowledge regarding food
safety issues. The need for guidance with regards to hazard analysis, implementation of preventive measures and regulatory
compliance is indubitable. There is also need to point toward the present difculty in the aquacuponics management and to
show the possible ecological and economical impacts.
Risk Management Systems
Aquaponics systems are commonly in vicinity of humans and that can be a serious concern for public health. Food safety
begins on the farm or in this case, in aquaponic systems. New methods are developed in order to detect infection or
contamination in sh, plants and their environment. Various biosecurity measures that prevent transfer of pathogens among
sh and environment may be implemented. Sometimes the absence of clinical symptoms does not mean the absence
(Continued on next page)
677
of pathogens and it should have in mind that such carriers could help in amplications of microorganisms. In the most
cases, producers are not aware that such microorganisms could be present in aquaponic systems. Producers should be
encouraged to implement preventive and control measures and risk management systems in order to prevent the occurrence
of pathogens in aquaponic systems. Good agricultural practice, good hygiene practice, good management practices and
management of wastes, feed, water and potential vectors are some of the current strategies.
Conclusions
Because sh meat can be potential reservoir of food borne pathogens, the necessity for education of people regarding
good hygienic practices should be highlighted. Education of food handlers is also signicant in order to decrease the
potential risk regarding food borne diseases. Moreover, the education of owners of aquaponic systems, veterinarians,
public, and health practitioners is very important. Monitoring and recording of occurrence should be the main operations
in the upcoming years which should moot questions of how to make better and put into actions the established directives.
References
Al-Hafedh Y. S., A. Alam, and M. S. Beltagi. 2008. Food production and water conservation in a recirculating aquaponic
system in Saudi Arabia at different ratios of sh feed to plants. Journal of the world Aquaculture Society 39: 510-520.
Kotzen B. and S. Appelbaum. 2010. An investigation of aquaponics using brackish water resources in the Negev Desert.
Journal of Applied Aquaculture 22: 297-320.
Lennard W. A. and B. V. Leonard. 2006. A comparison of three different hydroponic sub-systems (gravel bed, oating, and
nutrient lm technique) in an aquaponic test system. Aquaculture International 14: 539-550.
Ljubojević D., M. Pelić, V. Djordjević, L. Milojević, and M. Ćirković. 2016. Bacterial hazards in sh meat: The aetiologic
agents of foodborne diseases. Meat Technology 57: 27-38.
Radosavljević V., M. Ćirković, D. Ljubojević, D. Jakić-Dimić, Z. Marković, J. Žutić, and V. Milićević. 2014. Searching for
solutions in aquaculture: aquaponics. Arhiv veterinarske medicine 7: 71 – 78.
Rakocy, J.E., M.P. Masser, and T.M. Losordo. 2006. Recirculating aquaculture tank production systems: aquaponics—
integrating sh and plant culture. SRAC publication 454:1-16.
ResearchGate has not been able to resolve any citations for this publication.
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