FIELD OF THE INVENTION

The invention relates to the detection, assessment and mitigation of cyanobacteria in general and particularly to systems and methods for detecting, assessing and mitigating cyanobacteria in real time.

BACKGROUND OF THE INVENTION

The Centers for Disease Control (CDC) has recently launched a Harmful Algal Bloom (HAB) website in order to track widespread cyanobacteria bloom outbreaks nationally. A recent report from 2016 indicated harmful algal blooms outbreaks in 17 states in the month of September alone.

According to the CDC, algal blooms are quickly becoming a public health issue, resulting in symptoms ranging from mild to severe. Typical symptoms of HAB toxins include skin irritation, stomach and intestinal cramping, lung and central nervous system impairments. HAB toxins are harmful to both humans and animals.

Cyanobacteria blooms form when water is both warm and nutrient rich, for example from fertilizer runoff. The blooms typically appear in mid to late summer as the bodies of water begin to warm. Nutrients such as phosphorus and nitrogen help to feed this bacterium, which typically multiply during the night and rise to spread across a water's surface.

The appearance of cyanobacterium blooms often resembles floating green paint, which often give off a strong odor when they die. The blooms often block out light that organisms require to thrive in the water, as well as to deplete the water source of valuable oxygen. Cyanobacterium often produce cyanotoxins, which are dangerous natural toxins that cause a variety of harmful effects in both humans and animals.

Excessive algal growth as a result of an increase in growth factors needed to support photosynthesis, also known as eutrophication, causes an estimated at $2.2 billion dollars in damage annually in the U.S. alone. Often these damages are the result of blooms of blue green algae, also known as cyanobacteria, which contaminate drinking water supplies and recreational areas.

A typical consequence of vast blue green algae blooms is the foul odor that often emanates from decomposing algae as they die off. These dense blooms often block out the sunlight that is needed to help support organisms that typical thrive in the water, but become starved from sunlight as a result of the dense coverage that often lay on the surface of the water. As the algae die off, often-inorganic carbon is depleted that results in an increase in water pH levels. An additional consequence of decomposition is the depletion of dissolved oxygen, a factor that has been known to create hypoxic or anoxic conditions that are unable to support life.

More recently, hypoxic events have been found along marine coastal environments, such as those found along the Mississippi River, Gulf of Mexico, Susquehanna River, and Chesapeake Bay, which endanger lucrative commercial and recreational fisheries. These hypoxic events often impact large areas, for example approximately 245,000 square kilometers in these same areas. Of course, these events are not only limited to coastal marine areas, but they have also been found in many freshwater lakes as well, such as Lake Erie.

Recently an exceptionally hot weather pattern has pushed water temperatures in most of the Great Lakes to the highest levels on record so early in the summer. Over lakes Erie and Ontario, the water is the warmest it has been since records began being kept, and could warm more in the coming weeks. The abnormally warm waters, consistent with climate-change trends in recent decades, could compromise water quality and harm marine life in some areas. Surface water temperatures averaged over all of the Great Lakes, except the deep and choppy Lake Superior, have risen well into the 70 s while Lake Erie has flirted with 80 degrees.

Blue-green algae or cyanobacteria over western waters of Lake Erie in early July 2020. The foul-smelling algal blooms can harm fish and make people who are exposed to the water sick. In 2014, cyanobacteria from Lake Erie entered the water supply in Toledo, and residents were ordered not to drink or touch the water. The jump-start to the algal bloom due to the warm water temperatures means it will be around for several weeks longer than normal. The earliest observed algae blooms in the Great Lakes occurred in June in 2018.

Specific conditions which support the growth of algae blooms include water which embodies thermal stratification. This occurs when the upper layer of water is warmer than the lower layers, which often occurs when the two thermal layers stop mixing. This reduced thermal mixing often occurs when the waters are calm.

In the last decade, Lake Erie has experienced repeated harmful cyanobacteria blooms (cHABs) and cyanotoxins that have likely resulted in probable cases of human illness. A prevalent toxigenic cyanobacterium has been theMicrocystisgenus, which are known to produce microcystins. Furthermore, other cyanotoxins have also been identified, such as anatoxin-a, that implicate the presence of other toxigenic cyanobacteria likeAnabaena(Dolichospermum) andLyngbya.

The cells of cyanobacterium (Anabaena flos-aquae), are capable of producing neurotoxins, which have the capacity to interfere with the central nervous system. These neurotoxins can disrupt the communication between neurons and muscle cells, which can lead to death by causing paralysis of respiratory muscles.

Not all cyanobacteria produce blue-green algae, but some result in “red tides” or red water blooms. The same methods of the invention can be deployed against these bacteria as well.

Cyanotoxins are classified based on two criteria: (1) by their action mechanism in land vertebrates, which are broken into 3 sub-groups; hepatoxins, neurotoxins, and dermatotoxins; and (2) their overall chemical structure, which is also broken into 3 sub-groups; cyclic peptides, alkaloids, or lipopolysaccharides (LPS).

Hepatoxins can cause the rupture of structures within the liver by means of hypovolemic shock, resulting in excessive accumulation of blood within the liver. Hepatoxins can also interfere with the control of cellular structure and function of the liver by inhibiting protein phosphatases type 1 or 2 (PP1 or PP2A).

The most toxic compounds often produced by cyanobacteria are known as neurotoxins. These toxins can cause paralysis of the respiratory muscles by interfering with the neuromuscular system, which has been shown to cause death in laboratory rats in just minutes. One such neurotoxin are the saxitoxin type, also referred to as PSPs (paralytic shellfish poisoning), mainly due to how this toxin was first identified from humans consuming contaminated bivalve mollusks. These same toxins were also found to be the result of what has become known as the “red tide” phenomenon.

Cyanotoxins that are classified as dermatotoxins, aplysiatoxins and lyngbiatoxins have each been identified in marine cyanobacteria, which have been known to cause severe dermatitis for those who bath in coastal waters infected with the cyanobacteria.

In the prior art, chemical methods for controlling cyanobacteria growth have included the use of hydrogen-peroxide, which causes an oxidation process by which the hydrogen peroxide (H2O2) breaks down into water (H2O) and pure oxygen (O2), resulting in the death of exposed bacteria. The limitation here is that beneficial bacteria will also die as a result of its use, so great care is needed when employing this chemical agent. Another chemical method for controlling the spread of cyanobacteria is the use of antibiotics. Antibiotics such as Maracyn and Erythromycin have been found to be effective in killing cyanobacteria. Once more however the use of antibiotics to treat cyanobacteria will also interfere with the processes of beneficial bacteria as well.

Flesh eating bacteria have recently been identified as a problem in water, such as lakes, rivers, and the sea.

Standard Monitoring by Sampling a Body of Water

The standard procedure for sampling a body of water for Blue Green Algae (“BGA”) involves taking a water sample, sending it to a laboratory for testing, and receiving back a report. This process can take one or more days to complete.

Errors may be introduced during the transport of the sample.

It is known that BGA can double their numbers every 3 days if the conditions are favorable. BGA samples are sensitive to temperature and lighting conditions.

If the sample is illuminated (for example if held in a transparent or translucent container) it may continue to grow BGA. If the sample is held in an opaque container it may lose BGA (because in the dark, if held for sufficient time, some of the BGA may die). The rate of growth may be affected by the temperature that the sample experiences.

The delay involved in transporting the sample to the laboratory may be variable from sample to sample.

In any event, the data returned in the report may be days old (which may not the condition of the water at the time the results are obtained), and the result itself may not accurately represent the condition of the water at the time the sample was collected.

PATENT PRIOR ART

Also known in the prior art is de Meulenaer et al., U.S. Pat. No. 8,097,170, issued Jan. 17, 2012, which is said to disclose a device for treating liquid medium that has an ultrasound emitter located relative to a compartment of a container holding a liquid medium and a microbubble emitter located relative to the compartment. The ultrasound emitter emits high-frequency ultrasound between about 200 KHz and 10 MHz. The microbubble emitter emits bubbles with an average diameter of less than 1 mm.

Also known in the prior art is Kuwata et al., U.S. Pat. No. 8,849,483 issued Sep. 30, 2014, which is said to disclose systems and methods for operating autonomous waterborne vessels in a safe manner. The systems include hardware for identifying the locations and motions of other vessels, as well as the locations of stationary objects that represent navigation hazards. By applying a computational method that uses a maritime navigation algorithm for avoiding hazards and obeying COLREGS using Velocity Obstacles to the data obtained, the autonomous vessel computes a safe and effective path to be followed in order to accomplish a desired navigational end result, while operating in a manner so as to avoid hazards and to maintain compliance with standard navigational procedures defined by international agreement. The systems and methods have been successfully demonstrated on water with radar and stereo cameras as the perception sensors, and integrated with a higher level planner for trailing a maneuvering target.

Also known in the prior art is Song, et al., Korean published patent application KR 1020160031766A, published 23 Mar. 23, 2016, which is said to disclose a green tide removal apparatus using an UV-C lamp and an ultrasonic wave generator, which can prevent green tide by monitoring generation of cyanophyceae by measuring water quality of river, lake, etc., and by removing cyanophyceae during an initial stage of outbreak. The green tide removal apparatus of the present invention comprises: a main body having buoyancy so as to float on the water; an engine unit which generates power to move the main body; a power generation unit which generates electricity required to operate the engine unit; an analysis unit which measures water quality including population of cyanophyceae from a specimen obtained from corresponding waters; a treatment unit which removes cyanophyceae using ultrasonic waves and ultraviolet rays; a control unit which controls operation of the treatment unit depending on the population of cyanophycease measured from the analysis unit; and a communication unit which sends water quality data measured from the analysis unit to a control center so as to monitor generation of cyanophycease.

Also known in the prior art is Baltz, et al., U.S. Pat. No. 9,778,180, issued Oct. 3, 2017, which is said to disclose turbidometers and fluorometers having a unique form-factor to accommodate a number of optical components in a confined geometry. This provides the ability to compensate for change in light intensity from an optical source even in a closed-loop manner. The ability to package reference and signal detectors, along with a relatively large diameter LED light source in a confined geometry is particularly suited for applications requiring small-diameter sensors, such as multi-parameter sonde devices having a total diameter that is in the sub-two inch range. U.S. Pat. No. 10,393,654 issued Aug. 27, 2019 and U.S. Pat. No. 10,989,657 issued Apr. 27, 2021 issued from continuation applications of the above identified U.S. Pat. No. 9,778,180 and include similar disclosures.

There is a need for systems and methods to detect, to assess and to mitigate cyanobacteria and other harmful water borne bacteria in real time.

SUMMARY OF THE INVENTION

According to one aspect, the invention features an apparatus configured to mitigate a harmful water-borne bacteria, comprising: an aqueous monitoring sub-system configured to measure a concentration of algae in a body of water; an assessment sub-system in communication with the aqueous monitoring sub-system, the assessment sub-system comprising a microprocessor upon which can operate a set of instructions recorded in non-volatile memory, the assessment sub-system configured to provide a current value for a concentration of algae in the body of water, and configured to provide a predetermined reference concentration value; a control sub-system in communication with the aqueous monitoring sub-system and the assessment sub-system and configured to control the operation of the sub-systems, and to record data provided by the sub-systems; a mitigation sub-system comprising a UV illumination source, a source of microbubbles, and an ultrasonic transducer configured to apply, respectively, one or more of a UV illumination, a microbubble and ultrasonic sound to a quantity of the water to mitigate the growth of algae, in response to an instruction from the control sub-system; and a communication sub-system in communication with the control sub-system, the communication sub-system configured to transmit the data to an operator of the apparatus and to receive instructions for the operator for communication to the control sub-system.

In one embodiment, the apparatus is configured to reduce a concentration of a nutrient in the water to mitigate the growth of algae.

In one more embodiment, the nutrient in the water is phosphorus.

In still a further embodiment, the mitigation sub-system is configured to convert to molecular oxygen any of the ozone that remains after being applied to the quantity of water.

In another embodiment, the apparatus further comprises a flotation sub-system configured to allow the apparatus to operate as a water-going apparatus; a propulsion sub-system to allow the water-going apparatus to move relative to a body of water upon which it floats; a location sub-system configured to determine where the water-going apparatus is situated within the body of water; each of the flotation sub-system, the propulsion sub-system and the location sub-system in communication with the control sub-system.

In yet another embodiment, the apparatus further comprises an aerial observation sub-system tethered to the water-going apparatus and configured to provide information about the area adjacent the water-going apparatus, the aerial observation system in communication with the control sub-system.

In still another embodiment, the apparatus is configured to reduce the concentration of the algae directly.

According to another aspect, the invention relates to a method of mitigating a harmful water-borne bacterium, comprising the steps of: providing an apparatus comprising: an aqueous monitoring sub-system configured to measure a concentration of algae in a body of water; an assessment sub-system in communication with the aqueous monitoring sub-system, the assessment sub-system comprising a microprocessor upon which can operate a set of instructions recorded in non-volatile memory, the assessment sub-system configured to provide a current value for a concentration of algae in the body of water, and configured to provide a predetermined reference concentration value; a control sub-system in communication with the aqueous monitoring sub-system and the assessment sub-system and configured to control the operation of the sub-systems, and to record data provided by the sub-systems; a mitigation sub-system comprising a UV illumination source, a source of microbubbles, and an ultrasonic transducer configured to apply, respectively, one or more of a UV illumination, a microbubble and ultrasonic sound to a quantity of the water to mitigate the growth of algae, in response to an instruction from the control sub-system; and a communication sub-system in communication with the control sub-system, the communication sub-system configured to transmit the data to an operator of the apparatus and to receive instructions for the operator for communication to the control sub-system; operating the apparatus to collect a quantity of water; using the control sub-system to operate the mitigation sub-system to apply at least one of the UV illumination, the microbubble and the ultrasonic sound to the quantity of the water to reduce a concentration of a nutrient; thereby mitigating the harmful water-borne bacterium.

In yet another embodiment, the nutrient is phosphorus.

In still another embodiment, the mitigation sub-system performs the step of converting to molecular oxygen any of the ozone that remains after being applied to the quantity of water.

In one embodiment, the apparatus further comprises: a flotation sub-system configured to allow the apparatus to operate as a water-going apparatus; a propulsion sub-system to allow the water-going apparatus to move relative to a body of water upon which it floats; a location sub-system configured to determine where the water-going apparatus is situated within the body of water; each of the flotation sub-system, the propulsion sub-system and the location sub-system in communication with the control sub-system; and operating the water-going apparatus to reduce a concentration of the algae directly.

In another embodiment, the apparatus further comprises an aerial observation sub-system tethered to the water-going apparatus and configured to provide information about the area adjacent the water-going apparatus, the aerial observation system in communication with the control sub-system.

