MXPA98003486A - Method to control insects and mirrors with ultraviolet light impuls - Google Patents

Abstract

The present invention relates to a chemical-free, residue-free method for controlling pests, pathogens, and other unwanted organisms found in food supplies. The organisms are exposed to ultrashort pulses of ultraviolet light emitted at a wavelength, which is absorbed by the surface color chemicals in the insect, such as entegumeno. Colored chemists act as a thermal collector for ultraviolet photons, and unwanted organisms are selectively heated without damaging adjacent food objects. The heat of this form induced in insects, causes irreparable or irreversible lethal damage

Description

METHOD FOR CONTROLLING INSECTS AND MIRRORS WITH IMPULSED ULTRAVIOLET LIGHT DESCRIPTION OF THE INVENTION This invention relates generally to the control or elimination of insects or other unwanted organisms, and more particularly, to a method for causing irreparable or lethal damage to insects and mites using ultraviolet light driven at a wavelength, the which is absorbed through colored chemicals on the surface of organisms. • Insect controls are an important need in production and export agriculture as many regulatory barriers such as conditions that impose quarantines to transport food and agricultural products across regional, national and international boundaries. The use of insecticides and other chemical pesticides is usually the most used technique that has to do with insect controls. In the United States, as well as in many other countries, changes in public attitudes towards the use of chemicals to control pests are presented from the increased aspect of safety and preservation of food and conservation of environmental quality. Agricultural pesticides have been used extensively and intensively since the 1940s, resulting in a larger and safer food supply than the terrestrial population had ever seen. However, the concern regarding this technology has increased steadily as a result of environmental pollution and degradation, such as groundwater contamination and lack of ozone, as well as sporadic episodes of acute poisoning. Awareness and popular attitudes regarding these problems are reflected in ever-increasing regulatory actions aimed at agricultural pesticides. As regulations increase, the availability of agricultural pesticides is reduced. This has imposed new technological demands on agriculture and "can create new barriers to the international treaty of agricultural products and foodstuffs due to the quarantine regulations of commercial partners that can activate specific organisms. Therefore, there is a need for a method without chemicals, without residues to efficiently and effectively destroy insects in food supplies. The present invention satisfies that need, as well as others, and overcomes the shortcomings of the insect control technology of the prior art. The present invention generally relates to a method for exposing pests, pathogens and other undesirable organisms found in food supplies with electromagnetic energy in the ultraviolet spectrum, where the unwanted organisms are selectively heated and destroyed without causing harm to the food. By way of example, and without limitation, the method of the present invention comprises the steps of exposing insects and other organisms with a plurality of pulses of high frequency electromagnetic energy in the ultraviolet spectrum. The wavelength is chosen so that the ultraviolet light is absorbed by the surface color chemicals in the insect, such as integumeno, which acts as a heat collector for the ultraviolet photons. In this way, unwanted insects are selectively heated without damaging the adjacent food objects *. The heat thus induced in the insects causes irreparable or irreversible lethal damage. Accordingly, the present invention comprises a rapid physical method, without chemicals, without residues, to destroy insects, based on the use of monochromatic photons driven and selected from ultraviolet light, which can be generated through laser lamps or excimers. This method has the ability to replace the use of chemical pesticides, leaving no residue, and can be implemented either on a small scale with portable systems or on a larger scale, integrating it with existing technologies capable of handling large quantities of fresh food and other agricultural products such as packaging materials. further, due to its physical nature, there is no possibility for insects to develop resistance through genetic changes transferred to new generations, as is the case with most chemical pesticides. An object of the invention is to expose organisms with short pulses of electromagnetic energy. Another object of the invention is to generate thermal energy and selectively apply thermal energy to materials for disinfection purposes. Still another object of the invention is to effectively apply thermal energy to materials to eliminate or reduce populations of pests and / or pathogens. Another object of the invention is to selectively heat chemical products and / or target organisms through resonance. Another object of the invention is to selectively heat chemicals and / or organisms activated with ultraviolet energy without damaging adjacent food supplies or desirable organisms. Another object of the invention is to minimize or eliminate the use of agricultural pesticides to control insects.

Another object of the invention is to provide, in itself, the illumination of pests and / or pathogens in materials using the photothermal effect. Another object of the invention is to selectively kill or delay the growth of the pest and / or pathogenic organisms on beneficial organisms. Another object of the invention is to provide, activate or synergistically interact with natural processes that iit pests and / or pathogens. Other objects and advantages of the invention will be presented in the following portions of the specification, wherein the detailed description is for the purpose of fully describing preferred embodiments of the invention without placing limitations therein. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more readily understood by reference to the following drawings, which are for illustrative purposes only. Figure 1 is a flowchart showing the mortality rate of phylloxera eggs as a function of ultraviolet light energy exposure density at 308 nanometers. The interaction between electromagnetic energy and matter depends on the physical properties of the source, as well as on the chemical composition of the sample. The thermodynamics and kinetics of the thermally induced chemical actions that occur in a hot sample depend mainly on the chemical composition of the sample and many physical factors. The amount of radiant energy absorption of a target sample is a function of both the molecular structure thereof and the physical properties of the radiation, such as wavelength. In this way, matching the energy source with the target sample allows specific types of molecules to be electronically excited and irreversible chemical effects are obtained, including reactions that affect biological functions, such as cell division. In the Patent of the? .U.A. Number 5,364,645, which is incorporated herein by reference, it has been shown that irradiation of a food object with a powered ultraviolet laser beam causes irreparable damage to the nucleic base structures in microorganisms present in that object without altering the surface properties of the food object. The pulses having a duration ranging from about 1 ns to 100 ns, preferably 20 to 30 ns, and energy densities ranging from about 0.001 to 2 j / cm2, have been shown to be effective for this purpose.

The irradiation driven allows the use of higher energy levels with lower total energy requirements than with continuous heating and, therefore, is more efficient. In addition, the use of a highly powered energy source provides a higher temperature heating in a shorter period. - In this way, at energy levels where continuous wave heating could result in atomization of exposed molecules, the irradiation driven will result in thermal transfer without atomization. For impulse production on a scale of 1 to 2 j / cm2 per pulse, average energy levels can be as high as MW / cm2 foci. Irradiation using a plurality of pulses effects an almost instantaneous increase in the concentration of thermally excited molecules, while the thermal dissipation remains sufficiently slow to destroy the target microorganisms. In accordance with the present invention, the target organisms are irradiated by a plurality of ultraviolet energy pulses. In place of activation DNA, as in U.S. Pat. Number 5,364,645, the wavelength is selected such that selected photons in the ultraviolet region of 200-400 nm, and preferably in the ultraviolet region of 210-350 nm, are selectively absorbed by certain colored chemicals, such as enoxen , typically preeente on the surface of the insects. It has been found that these "melamine-type" chemicals are highly absorbent to ultraviolet light., and act as "thermal collectors", which rapidly convert ultraviolet energy to thermal energy creating small areas of intense heat that can not be dissipated and that causes irreparable or lethal and irreversible damage to the organism. These effects have been shown in all stages of biological development of insects, such as eggs, nymphs, larvae and adults. Significantly, it has been found that the selected wavelengths in the ultraviolet energy spectrum work much better than others because of the resonance characteristics of the different chemicals in the insect encumbrance. The termination of insects with selected narrow band wavelengths. { monochromatic or almost monochromatic) of ultraviolet photons in the region of 210 nm to 350 nm can also allow the selection of the types of insects that will be affected. In particular, it has been found that the picjment absorption of melamine has a peak at 222 nm. The effect of applying ultraviolet radiation in accordance with the present invention is rapid and irreversible, since exposure to selected ultraviolet photons occurs in extremely short pulses, or ultraviolet light pulses that last less than one microsecond. Therefore, the addition of even small amounts of energy, such as less than one millijoule, continues to produce a present heat with energy levels at the levels of kilo at or megawat, since one megawatt is equal to one millijoule per nanosecond. The conversion of ultraviolet energy to thermal energy in a specific ultraviolet absorption area, such as the target color pigments, produces an intense, absolutely instantaneous heat. Biological systems are not capable of rapidly dissipating these levels of heat energy and, therefore, biological structures are destroyed. For example, when pulses having energy "ranging from 200 to 400 millijoules per pulse and a pulse duration of less than 10 ns are generated from a monochromatic or quasi-monochromatic energy source such as excimer laser beams or lamps, and making a 100% conversion to thermal energy, the heat will be generated in the scale of approximately 20 to 40 MW per impulse. Since these excimer technologies can operate reliably with hundreds of pulses per second in the case of excimer lasers, and thousands of pulses per second in the case of excimer lamps, extremely high thermal energy can be produced and be sufficient to scan large areas with Suspected of containing insects, mites, eggs or other targets, quickly, and with high efficiency. Example 1 In order to demonstrate the efficacy of using ultraviolet-driven light to control insect populations, a variety of insects, mites and insect eggs have been selected to be irradiated with two monochromatic sources, 248 nm of a Lambda Physik excimer laser EMG-150 KrF, and 308 nm of an excimer laser of Lambda Physik EMG101 MSC ExCl. The samples were exposed using a variety of experimental fixations. Some samples were exposed to the fuel light beam from the laser (for high energy densities, 100 millijoules / cm2), * while other samples were exposed to an expanded beam of either divergent arrangements or a telescopic fixation (for low energy densities, <1 millijoule / cm2). Example 2 Coleoptera were subjected to 1 to 2 pulsed ultraviolet laser beam light pulses at 248 nm with approximately 100 mJ / cm2 of pulses. Coleoptera exposed to two impulses died almost instantaneously as a result of massive thermal damage. The thermal damage was clearly observed under amplification (30x stereoscope) and indicated a clear evidence of oxidation (brown), looking for (antennas) and the disappearance of clear pigmented areas in the entegum. Example 3 A group of Homoptera that vary in many nm from 1 to 2 cm in size were exposed from 1 to 3 pulses of ultraviolet light at 248 nm with approximately 108 mJ / cm2 of impulse. The amplified observations presented results similar to those observed for Coleoptera.

Death occurred almost instantaneously for most of these samples as a result of heat-induced damage as evidence of browning effects (oxidation). Example 4 Ants with a length of about 4 to 6 mm were treated with 10 pulses of an ultraviolet laser beam expanded at 248 nm with approximately 0. 8 mJ / cm2 pulses. The ants exploded shortly after the exhibition. Example 5 Phylloxera eggs with a size smaller than 1 mm, and adults of Tetranychus urticae (red mite), with a size of approximately 1 mm, were treated in leaves with energies varying from 25 mJ / cm2 to 2.3 cJ / cm2 from of an ultraviolet laser driven at 308 nm. 24 hours after exposure, a 90% reduction was established in the adult population. The treated eggs were oxidized (toasted) due to heat deposition. EXAMPLE 6 Phylloxera eggs with a size of less than 1 mm were exposed to an expanded light beam (diverging lens) from an ultraviolet laser driven at 308 mm. The eggs had a mortality of 70% with an exposure of 34.7 / cm2. Increasing the exposure to 66 J / cm2, there was a mortality higher than 97% for all the samples. Figure 1 shows the effect of mortality regime as a function of exposure energy for 3 different experiments, each with a different symbol (triangle, open box, solid box) on the graph, "representing a different experiment. EXAMPLE 7 The eggs of Hemiptera were treated with a size of approximately 1 mm with 1 to 5 pulses of 238 nm of ultraviolet photons from an excimer laser. The eggs showed brown effects. No egg matured. Ex «ampio 8 Acaros Brevipalpus Chilensis (similar to Brevipalpus californicus) with a size of less than 0.1 mm, were exposed to a direct beam of light from an ultraviolet laser driven at 248 nm. The total exposure increased progressively, while intermediate observations were made until the entire population was annihilated.

Depending on the size and maturity of the population, the energy needed for complete control ranged from 38.5 mJ / cm2 to 79.5 mJ / cm2. Example 9 Tables 1 and 2 summarize the experimental conditions and results of insect control according to the present invention. The experiments summarized in examples 1 to 8 and Tables 1 and 2 show that the ultraviolet-driven light is effective for the control of insects and mites, not only on a wide variety of species, but also for a variety of stages of development. Accordingly, it can be seen that the present invention provides efficient and effective control of organisms with ultraviolet light driven at a wavelength where ultraviolet light is absorbed through colored chemicals on the surface of such an organism., and where the absorption of ultraviolet light causes lethal damage to the organism through the conversion of ultraviolet light to thermal energy without altering the surface properties of adjacent food objects. The melamine-type color pigments that are characteristic of the particular insect being treated are carried out as thermal collectors for ultraviolet radiation. In essence, the irradiation becomes lethal to the insect as a result of the effect of "resonance" on the color pigments, as well as the photothermal effect of a rapid entry of energy. It will also be appreciated that part of the nervous system and vision is usually on the surface of an insect, however, the surface structure of the insect is affected without necessarily affecting the nervous system through the insect's sensory inputs such as vision and smell can be affected. Although the foregoing description contains many specific points, these should not be construed as limiting the scope of the invention, but merely provide illustrations of some of the presently preferred embodiments of this invention. In this way, the scope of this invention must be determined by the appended claims and their legal equivalents.

NJ or in cp TABLE 1 Ul TABLE 2 1. Wood bug (eggs adult) Bletforia (cockroach) nymph Wavelength: 248 nm Energy: 690 mJ / pulse Area: 28 cm2 Result: Sterilized eggs (unripened); dead adults. 2. Catarina (Coleoptera) Wavelength: 248 nm Density: 100 J / cm2 Impulses: 1 to 2 Results. Dead insect. Scorched antennas. Disappearance of * transparent pigmented areas in the middle. 3. Aphid Tenebriod Yellow Chrysnelid Aphid Rosas Exposure experiments were performed with without a telescope. Some of the numbers are inconsistent. Energy: 8 mJ / pulse. Density: After covering with the wrapping it represented 0.5 mJ / cm2 of impulse. Aphid Yellow 100 mJ / cm2 - 500 mJ / cm2 Tenebroide 1 J / cm2 - 5 J / cm2 Chrysonelid (Catarina) 0.5 J / cm2 - 1 J / cm2 Aphid Rose 100 mJ / cm2 - 500 mJ / cm2 Results: No observation. 4. Mite of Tetranychus urticae (red mite) Wavelength: 248 nm (a) Experiment 1: Energy: 24 mJ / pulse Density: 1.1 mJ / cm2 Impulses: 20 to 100 Results: Nin-guna observation. These data can refer to the following "Experiment". (B) Experiment 2: Different energy levels Density: 25 mJ / cm2 68 eggs 40 adults Results: After * 24 hours, ~ 4-5 adults survived (little movement); Density: 50 mJ / cm2 42 adults 72 eggs Results: After 24 hours, few adults remained alive (protected by the leaves) TABLE 2 - continued Tetranychus urticae (red mite) Acaro - continuation Density: 125 mJ / cm2 66 adults 77 eggs Results: After 24 hours, 5-6 adults survived, 60 died.

Density: 75 mJ / cm2 7 adults 100 eggs Results: After 24 hours, 1 of 7 adults lived. Little movement Density: 125 mJ / cm2 5 adults 70 eggs Results After 24 hours, 10-12 adults lived. Density: 1.4 mJ / cm2 32 eggs 14 adults Results After 24 hours, 3 adults in movement. Density: 250 mJ / cm2 16 eggs 3 adults Results: After 24 hours no eggs were affected, 1 adult survived. Density: 2.3 mJ / cm2 48 adults Results: After 24 hours, 6 adults in movement. 5. Bemesia Tabaci Wavelength: 248 nm Energy: 325 nJ / cm2 Results: After an impulse the insect "rolled up" died one minute after the application of the laser. 6. Aleyrodidae Homoptera (sweet potato whitefly) Wavelength: 248 nm Energy: 325 mJ / pulse. Result: After an impulse the wings of the insect rolled up; the eyes became darker; the insect died. 7. White fly of Ashes Wavelength: 248 nm Treated in Poinsettia (Euphorbia Eulcherrima). Energy: 22 mJ / cm 2 * Density: 1 mJ / pulse in cm2 Impulses: 5 to 300 Results: No recorded observation TABLE 2 - continued 8. Ants Wavelength: 248 nm In one set of experiments, the ants were "reduced in a freezer. All died including the controls. In another experiment, the ants "exploded". beam of light expd approximately 20 mJ / pulses, 0. 8 mJ / cm2, approximately 10 impulses. 9. Fruit fly (Assumed, not identified) Wavelength: 248 nm Energy: 18.5 mJ / pulse Impulses: 3-27 Results: No effects observed 10. Phylloxera eggs Wavelength: 308 nm Energy / eggs 2.3 x 10-2mJ to 40.5 x 10-2 mJ Results: None affected Wavelength: 308 nm Energy / egg 13.6 mJ - 68% mortality > 27.2 mJ - 100% mortality Comparison with UV Continuous low pressure (lamp Hg) Energy / egg 2.4 x 10-3 J a 2.4 x 10-2 mJ - no effect 8.1 x 10-2 mJ 20% mortality Wavelength : 308 nm Energy / egg 2.2 mJ - 2% mortality 29.8 mJ - 97% mortality Comparison with low pressure continuous UV (Hg lamp) Energy / egg 3.1 x 10-2 mJ to 23 x 10-2 mJ - without effect Wavelength: 308 nm Energy / egg 1.7 mJ - 10.2 mJ Results: No results reported Comparison with low pressure continuous UV (Hg lamp) Energy / egg 2.4 x 10-2 mJ at 15 x 10-2 mJ - no results reported Wavelength: 308 nm Energy / egg 2.2 mJ - 29.8 mJ - nin «no result reported Comparison with low pressure continuous UV (Hg lamp) Energy / egg 10 x 10-2 mJ at 240 x 10-2 mJ - no reported result TABLE 2 - continued Phylloxera eggs - continued Wavelength: 308 nm Energy / egg 8.2 mJ (38.5 mortality) 15.7 mJ (70.4% mortality) Comparison with low pressure continuous UV (Hg lamp) Energy / egg 10 x 10-2 mJ 29% mortality 240 x 10-2 mJ 98.9% mortality 11. Brevipalpus chilensis Wavelength: 248 nm No. of mites - 6 Density 5.7 mJ / cm3 mortality - 0% 17.1 mJ / cm3 mortality - 50 57 mJ / cm 3 mortality 100Í Wavelength: 248 nm No. of mites - 6 Density 5.3 mJ / cm mortality - 0% 15.9 mJ / cm2 mortality - 50% 53 mJ / cm2 mortality - 83% 79.5 mJ / cm2 mortality - 100% Length Wave: 248 nm No. of mites - 35 Density 5.5 mJ / cm2 mortality - 86% 16.5 mJ / cm2 mortality - 94% 38.5 mJ / cm mortality - 100%

Claims (9)

1. CLAIMS 1. A method for causing irreversible or irreversible lethal damage to an unwanted organism, characterized in that it comprises the step of irradiating an unwanted organism with a plurality of ultraviolet light pulses at a wavelength, wherein the ultraviolet light is absorbed by colored chemicals on the surface of the body, and where the absorption of ultraviolet light causes lethal damage to the body through the conversion of ultraviolet light to thermal energy. The method according to claim 1, characterized in that it further comprises the step of generating a narrow band ultraviolet light at a wavelength of between about 200 nm and 400 nm. 3. The method of compliance with the claim 1, characterized in that the light pulses have a duration ranging from approximately 1 ns to 100 ns. 4. A method for controlling unwanted organisms on the surface of food objects, characterized in that it comprises the step of irradiating an unwanted organism with a plurality of ultraviolet light pulses at a wavelength where the ultraviolet light is absorbed by chemicals of color on the surface of the organism, and where the absorption of ultraviolet light causes lethal damage to the organism through the conversion of ultraviolet light to thermal energy without altering the surface properties of adjacent food objects. 5. The method of compliance with the claim 4, characterized in that it further comprises the step of generating narrow band ultraviolet light at a wavelength of about 200 nm and 400 nm. 6. The method of compliance with the claim 5, characterized in that the light pulses have a duration ranging from approximately 1 ns to 100 ns. 7. A method for controlling unwanted organisms without altering the visual appearance of the food surfaces, characterized in that it comprises the step of irradiating the surface of a food object containing an unwanted organism with a plurality of ultraviolet light pulse to a length of wave where ultraviolet light is absorbed by colored chemists on the surface of said organism, and where the absorption of ultraviolet light causes lethal damage to the organism through the conversion of ultraviolet light to thermal energy without altering the properties of the surface of the food object. 8. The method according to claim 7, characterized by? Ne further comprises the step of generating narrow band ultraviolet light at a wavelength of about 200 nm and 400 nm. 9. The method according to claim 8, characterized in that the light pulses have a duration ranging from approximately 1 ns to 100 ns.