Marine Research Project
Beginning in 1991, our quest began with the purpose of solving the fouling problems found in the waters of the United States, i.e.: the fouling of boat bottoms and other common marine structures from the attachment of macro-foulers such as algae, barnacles and mussels, etc. Our approach to this problem, that a new biocide/pesticide could be developed that could solve this problem in a safe, ecologically correct manner, proved a thankless task. After several years of mixed results we finally came to the conclusion that a wholly different approach was needed.
Armed with only the thought that Nature is the source of the chemistry to solve mankind's needs and one must look to Nature for answers to problems that involve natural processes, an exploratory search was begun in 1994 to find marine flora that exhibited an ability to remain free of fouling in its natural environment. In a sense, mimic Nature's way. Now there is a name for this methodology, "bio-mimicry".
The thought being that if in Nature there exists marine life forms that remain clean while all around them exists various forms of marine fouling then it should follow that there could be a common denominator that could be identified and extracted for commercial use and by defination should be safe for the environment.
Over a ten year period, from 1994 to 2004, efforts were made to identify and collect samples of marine flora that exhibit the fore mentioned qualities. Over 170 marine plant forms were tested and analyzed for common compounds that might be responsible for its ability to stay free from attachment of the fouling life forms. I had assumed that we would eventually find a chloroform extract containing a toxic biocide with the ability to kill off invading marine macro-foulers. By the time this research was completed we had identified three compounds common to most of the samples. Much to our surprize, these compounds are also found in many common foods available for human consumption.
These compounds that we shall label here for discussion purposes as LIL, HMA and CAO, are safe, non-toxic and even nutritionally important. And when available in a specific ratio to each other has the ability to prevent fouling. How could these natural substances found in our everyday food supply prevent fouling on marine surfaces and would they still be effective once added to marine paints?
This apparent dilemma was solved with additional research when we discovered that by some means these compounds were not acting as a biocide nor as a pesticide as nothing was being killed, but were by some means actually repelling the bacteria in the water and keeping it from settling on the sub-merged surfaces. We were then able to determine that without this priliminary layer of motile bacteria (micro-fouling)settling on the sub-merged surfaces, no further fouling could occur.
Further research still found that these extracted compounds when added to marine paint, applied to sub-merged surfaces the contact with the sea water caused free radicals to form and become chemically active. The minerals and salts when in contact with the painted surfaces then became static charged thus attracting the motile bacteria and washing them away from the concerned surfaces.
In our field tests, after 2 years, the test panels are completely free of fouling. The resulting paints used are very hard and durable with projected life effectiveness of over 60 months. Tests were conducted in the Pacific SW, Cape Cod bay and the coastal waters of the Great Lakes.
The common forms of these extracted compounds are currently listed on both the EPA and the California DPR as safe and unregulated. These compounds are bio-degradeable and do not accumulate in the marine environment.
In conclusion, although copper is the biocide of choice for present day anti-fouling (AF) paints, it is also the major source of copper loading in the marine environment and, as such, could cause localized copper levels to exceed water quality standards. Measurements of copper levels in southern California, south Florida as well as other places show an accumulation of contamination close to marinas, boatyards, harbors and bays that often exceed state and federal water quality standards. It is estimated that in Port Canaveral, Florida alone copper output from only seven cruise ships to be 1.4 tons/year and in Indian River Lagoon is 1.7 tons/year from sailboats and 2.1 tons/year from motor boats. In many harbors of southern California the concentration levels in the harbor beds are at a saturation point to where the natural state of sea flora is greatly diminished.
In our field experiments, a reasonable concentration of the compounds HMA, CAO and LIL, in a ratio of 10% of dry weight of the paint, showed complete inhibition of bio-fouling. These results indicate that these strong bacterial repellents are both feasible in commercial applications and considerably more environmentally friendly.
As well, the resulting marine paints using these compounds as an additive formed harder, more durable and scratch free surfaces with expected useful life of 60 months or more, with no need to touch-up or clean surfaces.
The environmental impact of these AF compounds would be negligible as the isolated compounds are naturally degraded by several micro-organisms. Thus, there is no accumulation in the environment vs. the use of copper in marine paints. The use of these naturally derived AF compounds would further support the marine eco-system, as a healthier environment would result, able to host healthier marine flora, thus producing more oxygen to escape to the atmosphere while at the same time enhancing the oceans ability to consume carbon dioxide. (c) 2008.