RESEARCH, REVIEWS, PRACTICES AND ...

RESEARCH, REVIEWS, PRACTICES AND TECHNOLOGY

The Environmental Impact of Banana Production Can Be Diminished by Proper Treatment of Wastes Ricardo 0. Russo Carlos Hernandez

INTRODUCTION The environmental risks of banana production stem from the improper use of agricultural chemicals, poor disposal of plastic and degradable wastes, deforestation and erosion. The excessive use of agricultural chemicals and their poor application represent a problem which is not fully understood and needs more research for qualification and quantification. Ricardo 0.Russo and Carlos Hernandez are affiliated with the Agricultural College of the Humid Tropical Region-E.A.R.T.R, Las Mercedes de Guficimo, Costa Rica. The authors wish to acknowledge with thanks the valuable cooperation of Mr. David Fledderjohn from USAID for helping in English translation and text review. Journal of Sustainable Agriculture, Vol. S(3) 1995 O 1995 by The Haworth Press, Inc. All rights reserved.

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The Agricultural College for the Humid Tropical Region (E.A.R.T.H.), the National Banana Corporation (CORBANA) and Clemson University in South Carolina have formed a consortium called ECOBANA which intends to mount a program of exhaustive research to identify the problem and begin the search for alternative solutions. Currently, work is progressing to diminish other risks through the application of environmentally sound practices in the E.A.R.T.H. banana farm. This program involves concrete actions with waste bananas, main stems (pimote), plastic bags used to protect maturing stems, material used for bracing standiig plants and waste water from the packing plant. On the matter of deforestation, E.A.R.T.H. does not intend to expand planted areas by sacrificing standing forests; rather, plans are to increase natural forest area from the current 350 hectares to 1,000. An intensive reforestation effort has been started along river and stream beds, covering 15 meters on each side of all stream and rivers for the purpose of establishing natural forest filters and a corridor of biodiversity. Bamboo has also been planted to act as a screen between banana fields and populated areas.

METHODOLOGY Early in 1991, a project to develop an integral system for solid waste management was initiated to deal with not only the commercial farm but also wastes produced in other sectors of the University. This program was designed to be consistent with the principles and objectives of E.A.R.T.H., and thus, adaptable to conditions of neighboring communities of the humid tropics. When an evaluation was made of the total amount of wastes to be treated, it was found that 90% originate from the commercial banana farm which produces more than 640,000 stems per year. E.A.R.T.H. and the Industrial Engineering Department of the University of Costa Rica carried out a cooperative project to search for a solution to anticipate and dimiish the problem of contamination generated by the farm (Lizano and Murillo, 1991). The problem was researched extensively and five areas were identified in which the search for solutions was begun. Once these five problem areas were identified, concrete actions of waste treatment were undertaken to treat the products of each. Four categories of actions were developed as: Reduction; Reutilization;Recycling; Landfill. The five waste sources were defied as: (a) Culled bananas, (b) Main stems (pinzote), (c) Plastic bags, (d) Plant bracing material and (e) Waste water from the packing plant. On the matter of the excessive use of pesticides, the number of plastic bags impregnated with insecticides to protect maturing stems was reduced by declaring certain days of the week in which impreg-

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nated bags would not be used. Also, a specialized warehouse for pesticide management was built under strict specifications to protect workers and serve as a model for the region.

RESULTS Culled Bananas Each year, Costa Rica generates more than 270,000 tons of culled waste bananas which do not meet export market specifications; this represents 16% of all fruit produced (Hernandez, 1991). Since not all of this fruit is consumed or processed, the management of these wastes poses an environmental inconvenience. In E.A.R.T.H., the quality of fruit has improved with the installation of a cable system to transport stems from the field to the packing site and the construction of a modem packing plant. As a result of this, the cull rate has diminished considerably. The fruit which is not exported for reasons of size, maturity,or quality, is sold in the local market or is used as cattle feed in the commercial farm.

Main Stems or Pinzote The proper management of the pinzore (Figure 1) is critical since the volume of this waste reaches 225,000 tons per year; 94% of this weight is water (Hernhdez, 1991). Although it rots easily under natural conditions and its effects are short-lived, it is a temporary contaminant and has a foul odor. The material can also have a negative environmental effect if it is not handled properly and plastics impregnated with pesticides are left attached to the ends to be spread in fields or wherever it is dumped. In E.A.R.T.H., plastic bags are separated from the ends of the pinzote in the packing plant when the fruit bunches are separated from the stem (Figure 2). Stems are then hauled back to the banana fields and spread on the soil to let them decompose. In this way, some of the nutrients required by the crop are returned to the soil. However, banana stems contain a useful cellulose fiber (Blanco Rojas, 1991). The University of Costa Rica has developed research since 1970 and several theses have been done on the subject of paper production from banana stem fiber since then (Chivez RamIrez, 1981; L6pe.z Araya, 1981; Saborio Guzmh, 1981; Shedden Harris, 1978). Based on this, E.A.R.T.H. installed a pilot plant to make paper from this fiber. This plant was built from equipment which was

FIGURE 1. Utlllzat~onof banana raquis ("plnzote")as an organic matter add~tionto the soil In a bananaglantat~onin Costa-Rica. .-- - L-

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formerly used in the region to process abbaca fiber and was donated by the Guardia family, the former owners of the Las Mercedes farm. The process involves shredding the pinzote and placing it into a "Dutch tank" where the fiber separates from the pith. Then, this mixture is passed to a treatment tank where the fiber in suspensionis then placed on screens in order to make a sheet of cellulose fiber. The final step consists of solar drying under a roof and drawing sheets from rollers under pressure. This paper has a rustic appearance and is used in making products of relatively high value such as greeting cards, paintings, handicrafts and souvenirs. The fact that no chemicals are used in making this paper qualif~esit as a product for the green market The National Training Institute recently gave a course for women of the community on possible uses of this paper. Residual fiber kom the paper-making process is composted and used as organic fertilizer. Waste water, which is chemical-free,is sent to an oxidation pond. Recent tests of water from this pond showed that it contains only 3.6 ppm of suspended solids and its biological oxygen demand (BOD)is 9. Plastic Bags

The use of plastic bags to protect maturing stems of bananas was introduced in the sixties and has become a standard practice which cannot be eliminated without affecting production since no practical substitution has been found (E.A.R.T.H., 1992). The benefits of this practice include accelerated maturation and, therefore, reduced field time, plus insect control, principally against h i p s and beetles. The bags, which are usually impregnated with an insecticide, are tied to the upper part of the main stem when the fruit begins to develop and cover h e entire stem during the 12 to 15 weeks until it is harvested for packing. This plastic material is generated at about 67 kg'halyr, amounting to a considerable quantity of non-biodegradable waste which commonly ends up contaminating streams and rivers. In E.A.R.T.H., a continuous polyethylene tube material is being used in place of the pre-cut bags. This way, it is possible to use the minimum amount of material by cutting the tube to the exact length of the stem. With this system, a savings of 25% in material has been realized without increasing the labor costs of placement. The use of insecticide-impregnated material has also been cut by following a practice of using non-impregnated plastic some days of the week. Although a statistical evaluation has yet to be done, this has reduced the use of insecticides without any signs of decreased yields or fruit quality. Waste bags are returned to the bag supplier to be recycled for other uses, such as plastic pots. They are not considered a hazardous waste because the insecticide is degraded within 8 weeks and these bags are placed on the fruit stems for 14-15 weeks.

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FIGURE 2. Collectingplasticbags in the bananapacking plant at thecollege of Agriculture for the Humid Tropia Region (E.A.R.T.H.) in Costa Rica.


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Bracing Material for Plants Polypropylene twine has traditionally been used to hold up banana plants. This material is not degradable, is generated at about 80/kgma/yr, and stays in the fields from the moment that the plant is cut to harvest its fruit stem. The twine which stays on top of the soil inhibits root development over time, and causes problems with the growth of secondary shoots. In E.A.RT.H., this waste material is being gathered, compacted and sold to a plastic recycler who uses it as a raw material in the plastics industry for making low-grade plastic products. Because this is an expensive process, three other options for bracing plants are being experimented with to see which is the best: (1) the use of bamboo poles to hold up the plants, (2) aerial support from cables held in tension, and (3) the use of biodegradable twine. EffIuentsfrom the Packing PIant Banana packing plants use a large volume of water to wash the fruit. The water is contaminated with latex and solid wastes. A mechanical filter was developed in E.A.R.T.H. which acts to separate solids, and, at the same time, as a coagulator of the latex. The filter consists of a collection tank with a restricted outlet in which a set of double-screens are set to catch the solids. These trapped solids further act as a filter, trapping the latex which coagulates as the rate of flow is diminished. Every day, a rubber-tired front-end loader is brought in to take out the solids. Wastes generated from the filter are spread in the fields or used in making organic fertilizer. The plant uses about 12 liters per second of water pumped from a deep well. After passing through the filter described above, the water is run to the Parismina River after regular analyses. So far, these analyses have shown that this water is soft, with no detectable biocides; the concentration of iron compounds has been very low, at levels within the limits accepted by the World Health Organization, and the slight increase of aluminum does not exceed tolerance limits. It has also been determined that the D.B.O. is quite low (26 ppm.). Soon, this waste water will be recycled in the packing plant. DISCUSSION The experience of E.A.R.T.H. to date is showing that the environmental impact of banana production can be diminished through adequate waste treatment. If this can be maintained through time, it will constitute a significant contribution to the sustainability of the system which, if repli-

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cated on a regional level, could reduce the environmental impact of banana production in the region. Even further, it could become an effective model of sustainable development for the region. Sustainable development cannot exist if the by-products of economic activity degrade the natural resource base through contamination and the welfare of the human resource. The concept that environmentalprotection is solely a concern of ecological groups is being modified (Lorentan, 1992). Business activity must assume responsibility for protecting the environment even though this implies an environmentalcost; this &mation is one of the premises of the Business Council for Sustainable Development. Fortyeight business leaders from around the world have accepted the challenge and joined this organization (Brugger and Lizano, 1992). In the case of E.A.R.T.H., this waste management program is not cost-free and has obviously made farming less profitable in the immediate term. For instance, all of this process is estimated to increase the cost of producing a 40-pound box of bananas by $0.13. This represents 17%reduction in the net profit of the crop. Even though these processes are costly, they should not be evaluated in economic terms alone; rather, the social benefits of reduced contamination of the environment should be considered. A concept of total quality is being employed in which the process, from beginning to end, is examined to identify problems or limitations in diiferent stages, the solutions to which may eventually improve efficiency and lower costs. It is also a process of continual questioning of traditional methods which ends up being a "tradition-breaker." REFERENCES Blanco Rojas, M.L. 1991. Investigaci6n sobre la utilizaci6n de raquis de banano (Musa giant caavendishii AAA) para la producci6n de papel realizada en Costa Rica de 1979-1991. Brugger, E.k y E. Lizano. eds. 1992. Eco Eficiencia. La visi6n empresarial para el desarrollosostenibleen Am6rica Latina. Editorial Oveja Negra, S a m F6 de Bogota, Colombia. 371 p. Chlvez Ramireg M. 1981. Pulpeo mechico de raquis de banano, pino y por6. Royecto de graduaci6n para Licenciaturaen Ingenieria Quimica Universidad de Costa Rica. Escuela de Agricultura de la Regi6n Tropical H h e d a . 1991. Problemltica Ambiental del Cultivo de Banano en Costa Rica. Primer Taller, realizado el 24-25 de octubre de 1991. Escuela de Agricultura de la RegibnTropicalH h e d a . 1992 Problemltica Ambiental del Cultivo de Banano en Costa Rica. Segundo Taller, realizado el 14 de febrero de1992 (actas en preparaci6n).


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Hembdez, C. 1991. Cuantificacidn de desechos de la actividad bananera en Costa Rica, Indices de c6lculo. E.A.R.T.H. Las Mmedes, Gu6cimo. (docurnento interno no publicado) Lizano G., G. y J. Murillo J. 1991. Diseiio de una altemativa de soluci6n para prevenir y disminuir el problema de contaminaci6n generado por la actividad productura de b-o en la E.A.R.T.H. Royecto de Tesis para optar a1 grado de Licenciatura en Ingenieria Industrial. UNV. de Costa Rica, Fac. de Ingenieria. Esc. de Ingenieria Industrial. 193 p. + anexos L6pez Araya, E. 1981. Roducci6n de papel a partir de raquis de banano. Royecto de graduaci6npara Licenciatura en Ingenieria Quimica. Universidad de Costa Rica. Lorentzen, E.S. 1992. Nuestra empresa comh. In: Eco Eficiencia. La visi6n empresarial para el desarrollo sostenibleen America Latina. Editado por Bmgger, E.A. y E. Lizano. Editorial Oveja Negra, Santa F6 de Bogat& Colombia. pp. 79-83. Saborfo G u m h , C. 1981. Roducci6n de papel y cart611 a partir de raquis de banano. Proyecto de graduacidn para Licenciatura en Ingenieria Quimica. Universidad de Costa Rica. Shedden Harris, M. 1978. Estudio de raquis de banano (Musa giant cavendishii Lambert) e investigaci6n de sus posibles usos. Proyecto de graduacidn para Licenciaturaen Ingenieria Quimica Universidad de Costa Rica.

RECWED: 04/10/93 REVISED: 01/02/94 ACCEPTED: 01/10/94