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Here's more presticide info - this one in particular has a specific reference to ALS. In this same vein, something that may have a definite link to ALS, could also be extrapolated to having a possible link to pd - as in the case of the cycad seed poisonings in Guam, which resulted in ALS, AD, and PD. Note also the reference to chelation toward the end. Wendy Tebay ************************ --PART.BOUNDARY.claven.5681.2ff2d2fe.0001 Content-Type: text/plain; charset=us-ascii Confirmation of Poisoning Mercury content of blood and tissue can be measured by atomic absorption spectrometry. Special procedures are needed for extraction and measurement of organic mercury compounds specifi-cally. These tests are not generally available. --PART.BOUNDARY.claven.5681.2ff2d2fe.0001 Content-Type: text/plain; charset=us-ascii Methoxyethyl Mercury Compounds Methoxyethyl mercury acetate (MEMA, Panogen, Panogen M). Methoxyethyl mercury chloride (MEMC, Emisan 6, Ceresan). --PART.BOUNDARY.claven.5681.2ff2d2fe.0001 Content-Type: text/plain; charset=us-ascii Methyl Mercury Compounds Methyl mercury hydroxide, nitrile, benzoate, acetate, propionate, pentachlorophenate, quinolinolate. --PART.BOUNDARY.claven.5681.2ff2d2fe.0001 Content-Type: text/plain; charset=us-ascii Phenyl Mercuric Acetate Agrosan, Cekusil, Celmer, Hong Nien, Liquiphene, Mersolite, Pamisan, Phix, PMAS, Seedtox, Shimmer-ex, Tag HL 331, Unisan. Setrete (Gallotox, PMAA) is phenyl mercury ammonium acetate. These fungicides have been formulated as aqueous solutions and dusts. They have been used chiefly as seed protectants. Use of alkyl mercury fungicides in the United States has been virtually prohibited for several years. Phenyl mercuric acetate is still used to control diseases of turf, but other applications have been sharply restricted. --PART.BOUNDARY.claven.5681.2ff2d2fe.0001 Content-Type: text/plain; charset=us-ascii Toxicology and Manifestations of Poisoning The mercurial fungicides are among the most toxic pesticides ever developed, in terms of chronic as well as acute hazard. Epidem-ics of severe, often fatal, neurologic disease have occurred when indigent residents of less developed countries consumed methyl mercury-treated grain intended for planting of crops. Poisoning has also occurred when meat from animals fed mercury-treated seed was eaten. Most of what is known of poisoning by organic mercu-rial fungicides has come from these occurrences. Organic mercury compounds are efficiently absorbed across the gut and possibly across the skin. Volatile organic mercury is readily taken up across the pulmonary membrane. Methyl mercury is selectively concentrated in the tissue of the nervous system, and also in the red blood cells. Other alkyl mercury compounds are probably distributed similarly. Excretion occurs almost entirely by way of the bile into the bowel. The residence half-life of methyl mercury in the human is about 70 days. There is significant conversion of organic mercury to inorganic mercury in the red cell. Early symptoms of poisoning are metallic taste in the mouth, numbness and tingling of digits and face, tremor, headache, fatigue, emotional lability, and difficulty thinking. Manifesta-tions of more severe poisoning are incoordination, slurred speech, loss of position sense, hearing loss, constriction of visual fields, spasticity or rigidity of muscle movements, and deterioration of mental capacity. Many poisonings caused by ingestion of organic mercurials have terminated fatally, and a large percentage of survivors have suffered severe permanent neurologic damage. Phenyl mercuric acetate is apparently not as extremely toxic as the alkyl mercury compounds. However, exposure to it has preced-ed the appearance of symptoms and signs of neurologic disease resembling amyotrophic lateral sclerosis in certain reported instances. --PART.BOUNDARY.claven.5681.2ff2d2fe.0001 Content-Type: text/plain; charset=us-ascii Treatment of EXTERNAL Toxicosis Skin and hair contaminated by mercury-containing dust or solution should be cleansed with soap and water. Eye contamination should be removed by flushing the eye with clean water. If irritation persists, specialized medical care should be obtained. Persons experiencing symptoms (metallic taste in mouth) after inhalation of volatile organic mercury compounds (methyl mercury is the most volatile) should be removed promptly from the contam-inated environment, and observed closely for indications of neurologic impairment. Every possible precaution should be taken to avoid exposure to organic mercury compounds. --PART.BOUNDARY.claven.5681.2ff2d2fe.0001 Content-Type: text/plain; charset=us-ascii Treatment of Toxicosis by INGESTION Ingestion of organic mercury compound, even at low dosage, is life-threatening, and management is difficult. Detailed discus-sions of contemporary treatment options are offered in modern clinical toxicology texts. Following are the basic steps in management of poisoning. 1. Limit gastrointestinal absorption. If a mercurial fungicide has been ingested in the past few hours, the stomach must be evacuated by intubation and lavage, taking all precautions to protect the respiratory tract (see Organophosphate Insecticides, Treatment). Repeated administration of activated charcoal may be beneficial. 2. Administer a chelating agent. Dimercaprol (BAL) and EDTA are apparently of little value in poisonings by organic mercury, but other chelators are effective: A. D-penicillamine. (This is available in the United States, and has proven effective in reducing the residence half-life of methyl mercury in poisoned humans, see Arsenical Pesticides for dosage.) B. 2,3-dimercaptopropane-1-sulfonate, and 2,3-dimercaptosuccinic acid. (Although effective, these agents are not currently approved for use in the United State.) C. N-acetyl-D,L-penicillamine. (Effective, but not currently approved for use in the United States.) 3. Extracorporeal hemodialysis and hemoperfusion may be consid-ered, although experience to date has not been encouraging. Although the unmodified organic mercurials are not efficiently dialyzable across most membranes, when used in combination with chelating agents, dialysis may be of some value in removing organic mercury from the blood (A.H. Al-Abbasi, et al. J. Pharmacol. Exptl. Therap. 207:249-254, 1978). Very little can be done to mitigate neurologic damage caused by organic mercurials. --PART.BOUNDARY.claven.5681.2ff2d2fe.0001--