HOME
21ST CENTURY BAIT
DECOMPOSITION
APPLICATION
EXPERIMENTS
2007 TEST RESULTS
Our Efforts for the Protection of the Environment
Creation of bait for the 21st century
Decomposition tests of bait in the ocean
Application of decomposing bacteria and minerals
Experimental report on the decomposition of biodegradable worms
Decomposition Test Results Update 2007 **NEW!**
Biodegradable plastics are "plastics which can be used as conventional plastics, while at disposal they will decompose into water and carbon dioxide by the action of microorganisms commonly existing in the natural environment." A similar definition is offered by the ISO (International Organization for Standardization) as well. In Japan, biodegradable plastics are called "GreenPla." And there is a GreenPla Identification and Labeling System established by the Biodegradable Plastics Society (BPS) to distinguish biodegradable plastics from ordinary plastics. All plastic products which satisfy the certification standards for product composition, biodegradability, environmental safety, etc., are certified as "GreenPla" products.
Currently, there are three types of biodegradable plastics, namely, the microbiologically produced polymer type, the synthetic polymer type and the natural polymer type - all of which are completely biodegradable. On the other hand, there are also "degradable" plastics, which are general-purpose plastics that have an added decomposition accelerator (catalyst) or a natural polymer (starch, etc.). These plastics actually undergo degradation or decay, but the plastics themselves (polyethylene, etc.) may remain in the environment as invisible particles. Even when they have decomposed, it still takes a number of years (several tens of years or longer) before they are completely decomposed and dissolved into the ecosystem. In essence, therefore, these cannot be called biodegradable plastics. (Source: Professor Haruyuki Kanehiro, Department of Ocean Sciences, Faculty of Marine Science, Tokyo University of Marine Science and Technology.)

Therefore, biodegradable plastics are as defined above. In other words, they are plastics that cannot be called biodegradable plastics simply because they lose their form (and become invisible to the human eye). They must completely enter into the cycle of nature before they can be considered full-fledged biodegradable plastics.

Our challenge has always been to come up with biodegradable plastic worms, which are not only perfectly biodegradable but are also capable of catching fish. No compromises whatsoever, such as "Biodegradable, but not attractive to fish" or for "Fishing first, and biodegradable next" were considered. Our biodegradable plastic worms are all "natural" or "biodegradable" - from material plastic and coloring agent to the lam. As for the capacity to "attract fish," our products feature forms maximizing the characteristics of the biodegradable materials, as well as tempting movements in the water and other factors that appeal to fish. And, of course, our products are put on the market only after the most demanding of tests. We initiated research into biodegradable plastic worms 12 years ago. We set our aims to be products true to the definition of biodegradable plastics as defined by the BPS (Biodegradable Plastics Society) or by the ISO. We now design all our ECOGEAR biodegradable plastic worms so that they can be given the "GreenPla" designation.
The definition, therefore, of biodegradable plastics are "plastics that can be used in the same way as ordinary plastics but, after use, can ultimately be decomposed into water and carbon dioxide by the action of microorganisms in nature." The principal material used in ECOGEAR's biodegradable plastic worms is a resin called aliphatic polyester. Polyester is a combination of esters. An enzyme called lipase in microorganisms breaks up esters into alcohol and acid, which are eventually turned into water and carbon dioxide. The main material of ECOGEAR's biodegradable plastic worms is therefore nontoxic and friendly to the environment. Now what about the mixed-in materials, such as the coloring agent and lamé? Our good intentions would be ruined if such materials as were not present in nature were used for the coloring and other auxiliary parts of our worms. As a coloring agent for our biodegradable plastic worm series, we have selected a harmless pigment used in cosmetics. For black lamé
ECOGEAR worms are not only biodegradable but also have a taste and smell fish cannot resist. Our brainchildren include "E-TUBE" introduced in 2001 and "PAD GRUB" and "LAYDOWN" marketed in 2002. In 2004, "GORI-GORI" and "PUCHI-EBI" were put on the market. All our ECOGEAR worms undergo repeated tests in the field and in the laboratory and their biodegradability and attraction to fish are confirmed before they are put on the market.
Our development of biodegradable plastic worms is going on both in the laboratory and in the field. Our tests in the laboratory have confirmed that aliphatic polyester, which is our main material, decomposes into water and carbon dioxide. However, worms are used in rivers and oceans. That is, in the field. So our tests are being carried out in the clear water lakes of the mountains, the muddy water of the ponds on flatlands, and in the seawater of the oceans, as shown on the next pages.
Biodegradability Tests in a Saltwater Area (Cooperation: The Shimoda Floating Aquarium)
ECOGEAR is highly reputed as a supplier of soft lures for ocean fishing. Our biodegradable plastic worm series, of course, assumes use in the ocean, therefore testing in saltwater in the field is a must. With the help of the Shimoda Floating Aquarium, we are now conducting biodegradability tests in seawater.
Biodegradability tests were started in April 2002 at the Shimoda Floating Aquarium in the Izu Peninsula. The location is open to the ocean and is under the influence of the Japan (Kuroshio) Current, which keeps the water temperature relatively high throughout the year. An ideal place for biodegradability testing in seawater.
Testing was started in April 2004. The test points were by the side of a dolphin breeding tank and at the water tank for pumped-up seawater. A total of 32 samples, including E-TUBE and pilot samples, are being put to the test. They are raised out of the water at regular intervals to check on the progress of degradation, take weight measurements and to obtain other data. The area near the Shimoda Floating Aquarium in the Izu Peninsula is near the Japan (Kuroshio) Current, and as a result, the water temperature is relatively high at about 19˚C throughout the year. It has been found that the rate at which the samples decompose here is faster here than that at the Hanyu Yoshinuma Reservoir, where similar tests were conducted in freshwater (with an abundance of microorganisms).
Seawater Field Tests (The Shimoda Floating Aquarium)
Appearance on the first day of testing. The test samples are new, pure white "E-TUBE" items. "E-TUBE" samples 19 months after the start of the tests. The skirt portion has all gone.
The surface of the tail portion of "E-TUBE" at the start of the biodegradability tests. 100-fold magnification by electronic microscope. The surface of the tail portion of "E-TUBE" 19 months after the start of the saltwater-area biodegradability tests. 100-fold magnification by electronic microscope.
Field Tests Biodegradability Test I in a Freshwater Area (Cooperation: The Ashinoko Fishery Cooperative Union)
At Lake Ashinoko, a total ban on worm fishing was put in place on March 1, 2000. However, ECOGEAR chose this lake for our biodegradability tests because this area has cold, clear water containing fewer microorganisms. The water temperature during the tests was an average of 14˚C and the rate of decomposition was slow. Yet, it was apparent that our biodegradable plastic worms show much faster decomposition than the control samples of vinyl chloride.
Test results (4 years) at the Anglers' House Yamaki Upper 2 items: Vinyl chloride material samples Lower 2 items: Biodegradable material samples (Both of the straight-type, 3-1/4 in length)
Hakone-wan point (Cooperation: The Anglers' House Yamaki) Five samples for the biodegradability tests were prepared, which included prototype biodegradable plastic worms and vinyl chloride worms as controls. The tests were carried out at the pier of the Anglers' House Yamaki. Kojiri point ( Cooperation:The Fishing Center Ooba)
A total of 32 samples were prepared, including "E-TUBE" biodegradable plastic worms and pilot products. As with the other biodegradation tests, sample weights and other measurements were taken regularly and the biodegradability data was recorded.
Samples at the Anglers' House Yamaki Samples at the Fishing Center Ooba
Biodegradability Test II in a Freshwater Area (Cooperation: The Hanyu Yoshinuma Reservoir)
The Hanyu Yoshinuma Reservoir, a water body for irrigation, in Saitama prefecture is a managed pond for artificially cultured crucian carp fishing. Located in a flatland, the pond has water containing an abundance of microorganisms. The situation is very similar to the ones often found for bass fishing. Thus, precious data can be obtained from the biodegradability tests at this location. The water temperature is an average of 16˚C and there is a high organic level of COD. In this highly nutrient field, the decomposition speed was found to be quite high, and in 42 months, "E-TUBE" was in the final stages of decomposition.
ECOGEAR is conducting energetic R&D for the development of further advanced biodegradable plastic worms. Also, the decomposition tests of our products are being carried out with the help of Professor Kanahiro of Tokyo University of Marine Science and Technology, at the Department of Ocean Sciences, the Faculty of Marine Science. Verification of the differences in biodegradability in different fields will help us develop better products.
Freshwater Field Tests (Hanyu Yoshinuma Reservoir)
"E-TUBE" one month after the start of the testing. Shrinking can already be observed. "E-TUBE" samples 19 months after the start of the tests. Degradation has advanced considerably, and the adhesion of microorganisms can be seen.
The surface of the tail portion of "E-TUBE" at the start of the biodegradability tests. 100-fold magnification by electronic microscope. The surface of the tail portion of "E-TUBE" 19 months after the start of the freshwater biodegradability tests. 100-fold magnification by electronic microscope.
The items for water quality measurement included: the water temperature, the pH, the COD, and the concentrations of nitrates, nitrous acid, hydrogen sulfide, phosphoric acid, ammonia, etc. The test samples are individually placed in plastic nets and then further protected by stainless steel baskets.
Acknowledgement In developing our biodegradable plastic worms, ECOGEAR is conducting tests with the invaluable cooperation from the Ashinoko Fishery Cooperative Union, the Ashinoko Fishing Center Ooba, the Anglers' House Yamaki, the Hanyu Yoshinuma Reservoir, the Shimoda Floating Aquarium and the Tokyo University of Marine Science and Technology.
Copyright (C) 2006 Marukyu Co., Ltd. All Rights Reserved.