Floating larvicide

Abstract

Abstract MALARIA, YELLOW FEVER AND SIMILAR DISEASES ARE SPREAD BY WATER-SPAWNED ORGANISMS PARTICULARLY THOSE THAT GO THROUGH A LARVAL STAGE IN THEIR LIFE CYCLE. MOSQUITOES ARE ATTACKED IN THE LARVAL STAGE WITH ORGANIC PHOSPHOROTHIOATE LAVICIDES, CHLORINATED HYDROCARBONS, AND ADDITION PRODUCTS OF ETHYLENE OXIDE AND ALIPHATIC ALCOHOLS SUCH AS OLEYL ALCOHOL WHICH KILL LARVAE WHEN SPREAD UPON AN INFESTED WATER SUPPLY. DIRECT DISPERSION OF THE TOXICANT OR TOXICANT WITH KNOWN CARRIERS ONTO THE INFESTED WATERS HAS VERY LIMITED PERIODS OF EFFECTIVENESS AGAINST THE LARVAE AND SIMULTANEOUSLY POLLUTES WATER. IT IS DISCOVERED THAT DELAYED TOXICANT RELEASE, MUCH LONGER PROTECTION, AND LESS WATER POLLUTION RESULT WHEN CERTAIN TOXICANTS ARE DISSOLVED INTO A PARTICULAR ELASTOMERIC MATRIX AND THEN PELLETS OR PIECES OF THE RESULTING COMPOSITION (PREFERABLY IN VULCANIZED FORM) ARE DISPERSED UPON THE INFESTED WATER. ETHYLENEPROPYLENE-DIENE TERPOLYMER RUBBERS KNOWN AS EPDM RUBBERS ARE SUITABLE ELASTOMERS FOR THIS PURPOSE. WHEN THE ELASTOMERIC-TOXICANT COMPOSITIONS ARE IN FLOATLEASED SLOWLY FROM THE COMPOSITION INTO THE WATER AT THE WATER SURFACE AND THE COMPOSITION IS CAPABLE OF MAINTAINING A TOXIC CONCENTRATION TO LARVAE FOR PERIODS OF MONTHS IN STAGNANT WATER. THE LARVICIDAL ELASTOMERIC (OR RUBBER) COMPOSITIONS CONTAIN AN ORGANIC TOXICANT DISSOLVED IN A VULCANIZED EPDM RUBBER MATRIX SPECIALLY COMPOUNDED AND CURED IN SUCH A FASHION THAT THE TOXICANT REMAINS SOLUBLE AND SUFFICIENTLY MOBILE IN THE MATRIX AS TO DIFFUSE TO THE SURFACE OF THE MATRIX AT A SELECTED, CONTROLLED RATE AND TO BE RELEASED AT A RATE ADAPTED BEST TO CARRY OUT THE LARVICIDAL APPLICATION.

Inventors

• 👤 Nathan F Cardarelli
• 👤 Joseph C Hess

Bibliographic Details