Poisons

_{-- P o i s o n s --} _{click on the question number for the answer}
Q 1.
	Is it true that no poisonous fish has ordinary scales?
Q 2.
	Is the filefish edible?
Q 3.
	Do poisonous food fish form a special biological group?
Q 4.
	Are all filefish poisonous to eat?
Q 5.
	What is tetraodontoxin?
Q 6.
	What is the difference between "poisonous" fishes and "venomous" fishes?
Q 7.
	How do clams and oysters become polluted?
Q 8.
	Are balloonfish good to eat?
Q 9.
	Several people have told me that filefish and triggerfish are good to eat, but others have said that these fish are poisonous. Can you tell me anything about this?
Q 10.
	Is the rabbitfish that we catch on party or “head” boat trips good to eat?
Q 11.
	How can you tell if a barracuda is poisonous?
Q 12.
	Can you tell me whether the common toadfish or blow-fish is considered edible? We have tried them and found them to be so, but we have started many arguments about them since many people believe them to be highly poisonous. I know they will almost kill a cat if eaten raw. Does cooking destroy whatever poison they may contain?
Q 13.
	One of my neighbors fed some raw blow-fish to his two kittens early in the evening and found the kittens dead the next morning. Is the blow-fish poisonous when eaten raw at this time of year?
Q 14.
	I have been told by many people that the fish I call blow-fish are good eating, and yet others tell me that they are called puffers and are poisonous. The fish to which I refer inflate themselves like a balloon and have a skin like sandpaper. They also have teeth like a clamp and bite down on the hook when they are caught. Is there such a fish as the poisonous puffer? If there is, how does it differ from a blow fish? Also, which one is edible?
Q 15.
	For many years, we have been catching blow-fish in the coastal waters from New Jersey to Massachusetts have eaten the meat of these fish and have found it to be both tender and delectable. Is there any chance of poisoning after blowfish are cooked?
Q 16.
	Recently we had a raw conch salad for lunch. I selected the conch myself-large, very white and with lively muscle reaction. Yet, my three children, two maids and myself became very ill after eating the salad. The doctor prescribed Allen & Hanbury's (England) "Guanimycin" tablets, which gave us immediate relief from the cramps and pains. There may have been a Samba conch in the lot but I understood the Samba flesh is rather yellow. Or the conch may have been washed in harbor water, but tests have shown very little pollution there.
Q 17.
	In the Virgin Islands the natives are constantly warning that such and such a fish feeds on the "copper banks" and is poisonous, if eaten. I consider this nonsense but would like to hear your opinion.
Q 18.
	I have read where people have been poisoned from eating barracuda. What causes the barracuda to be poisonous at times?
Q 19.
	Several of my patients attended the same dinner party and ate what presumably was a sea trout which was supposed to have been caught in the Gulf of Mexico. Several developed nausea, vomiting and diarrhea, and all developed numbness, tingling, itch and marked weakness. This was obviously a neurotoxin of some type. The material was taken to a laboratory, but no pathological organism was found. Apparently the neurotoxin was in the fish itself. Have you heard of such a thing occurring in sea trout? Also, does this seem similar to the type of neurotoxic effect observed after eating barracuda?
Q 20.
	Could you furnish me information concerning the specific species of toadfish that are toxic, and the nature of the poison?
Q 21.
	It is possible for a toxic fish to obtain toxin through inheritance?
Q 22.
	How can one distinguish edible from poisonous fishes?
Q 23.
	I have recently read articles about fish poisoning, called by the name ciguatera. What are the symptoms for diagnosis and what is the remedy?
Q 24.
	For some time I have been eating barracuda speared in our area at least once a month or oftener when possible. Our health department has no record of barracuda poisoning and a marine biologist in the area feels that reported cases of poisoning by barracuda from the Florida Keys were simply due to decayed meat. At the same time commercial fishermen in this area insist that barracuda poisoning does exist, and they will have no part of eating barracuda. Could you please help solve this discrepancy by sending me any references to medical articles on the subject and your opinion with regard to the etiology of barracuda poisoning?
Q 25.
	A recent book I've read listed the rabbitfish as an excellent food fish and stated that it has some sort of poisonous sack. Can you tell me where this sack is located and how it can be identified? Would this same procedure apply to the blowfish which was also listed as an excellent food fish?
Q 26.
	We have read of people dying from eating barracuda, which we understand is sometimes poisonous. Is this true of barracudas along the west coast of Africa? We have never heard of such a case here.
Q 27.
	According to an article we recently read, blowfish are poisonous to eat. Many people, including myself, skin the back of this fish and remove two white tenderloins, one on each side of the spine. The quality and texture of this meat is similar to scallops. It is known by a variety of names, including "Chicken of the Sea." In many of the tide-water areas around the Chesapeake Bay it is considered a delicacy. Would you care to comment on the allegation that this fish is poisonous?
Q 28.
	I have heard that fishes known as puffers are a delicacy. In a recent magazine article, however, the statement was made that puffers highly poisonous. Should we or should we not eat puffers that we catch?
Q 29.
	While cruising the British Columbia waters of Georgia Strait in July, 1965, I was warned that there had been a “red tide,” and that therefore the clams were dangerous to eat. I was also told that oysters were not affected and so could be safely eaten. Are only clams affected by the red tide, or are oysters also rendered poisonous?
Q 30.
	In Sea Secrets for May, 1966 (Vol. 10, No.5) it is suggested that one can contract hepatitis from raw clams, and that cooking them does not eliminate the danger. Would this also apply to raw oysters, cooked oysters and steamed mussels?
Q 31.
	I recently read a newspaper article stating that the blowfish was excellent table fare, if you did not eat the liver or roe. Is this true? I thought the whole fish was poisonous.
Q 32.
	A well-known surgeon who has spent a lot of his time in the arctic regions has told me that the liver of the polar bear is so high in vitamin A that it is poisonous to humans as food. He assumes too that all animals of that region, including the natives, have a high vitamin A content and thus have better vision in the brighter sunlight.
Q 33.
	At the present time the commercial fish importing industry is in a state of chaos as a result of the Food and Drug Administration's action with respect to mercury. There appears to be a great difference of opinion concerning the value or danger of mercury and mercury compounds. There does not seem to be any firm scientific evidence with respect to what level and what form of mercury is dangerous. Could you shed any light on the subject?
Q 34.
	Can you tell me the test procedure for determining the amount of mercury in fishes?
Q 35.
	When testing for mercury in fish, is the entire fish ground up and then tested, or are the entrails separated from the fish, or is the edible flesh tested separately?
Q 36.
	The enclosed fragment of a metallic-looking substance was taken from the stomach of a 21/2-pound hind caught in our waters. Fragments of this type have also been found in the flesh and heads of groupers. I have been told that these fragments must be removed before cooking the fish as they are poisonous, and recently some people had to be hospitalized after eating grouper without removing them. Can you tell me what the fragment is?
Q 37.
	I am enclosing a list of shell-bearing molluscs from the Florida Keys. Can you tell me which are edible by man?
Q 38.
	The clams and oysters of Sarasota County waters are inedible because of pollutants. I have heard that they can be purged by keeping them in a wide-mesh metal basket in Gulf of Mexico waters. If so, how long does this process take, how deep must the water be, and can they be stacked in the basket or must they be in a single layer?
Q 39.
	Is it safe for me to eat meals containing raw fish caught near the southwest pass of the Mississippi River?
Q 40.
	It is customary in Bahamian and West Indian villages to keep conchs, beneath the docks. Many of these harbors have limited inflow and outflow and, at the same time, are populated with visiting yachts which discharge waste into the harbor. Why is the incidence of hepatitis so low from eating raw conch so exposed to human waste? Does the conch's lack of a filterfeeding mechanism make it less susceptible to picking up the virus?
Q 41.
	I frequently scuba dive near the Miami and Hollywood sewage outfalls. Is it safe to do so, or to eat fishes or lobsters caught near them?
Q 42.
	Is the roe of the black, long-spined sea urchin found in Florida and the Caribbean edible?
Q 43.
	Is there any way to tell if a fish contains the poisons that cause ciguatera prior to eating it?
Q 44.
	In Sea Frontiers and in Sea Secrets, it was suggested recently that pieces of fish flesh be fed to a mongoose or a cat to test the fish for ciguatoxin. Would it be advisable instead to feed the test animal a piece of the fish's liver, which would be expected to concentrate the toxin? Also, what quantity should be given to the test animal, without inducing needless illness?
Q 45.
	After reading question 3523 in the May-June issue of Sea Secrets, would like directions on processing eggs from fishes I catch for use as caviar and bait. Where is this information available?
Q 46.
	Can escargot be prepared from marine snails?
Q 47.
	Why do we find a "coral" attached to European scallops and not to scallops sold in the United States?
Q 48.
	Are squids venomous? Are they poisonous?
Q 49.
	In the January-February Sea Secrets, question/answer 3786 indicated that the neurotoxins produced by Ptychodiscus brevis - the Florida red-tide dinoflagellate - are very potent. Just how potent are these toxins, and what is the potential human susceptibility to them in affected waters?
Q 50.
	Are there worms in the marine fishes commonly served raw as sashimi and sushi? If so, are the parasites harmful to people?
Q 51.
	What was the cause of the 1978 cholera outbreak involving 11 residents of Abbeville, Louisiana?
Q 52.
	I have been warned that the Florida horse conch can be poisonous to eat. Is this true?
Q 53.
	I recently read an account of how the Cousteau camera crew aboard the Calypso suffered ciguatera poisoning after eating barracuda in Haiti in August 1985. Can you provide a list of the tropical fishes that one should not eat in order to avoid getting ciguatera?
Q 54.
	I saw a South Pacific nature film that showed a moray being cooked along with other fish. I believe that this kind of eel can be a carrier of ciguatoxin, which causes ciguatera poisoning in humans. Am I right?
Q 55.
	I have heard that there is a quick dipstick test that fishermen can use on their catch to determine if the fish are ciguatoxic. Is this true?


_{-- a n s w e r s a b o u t P o i s o n s --}
	Q&A 1.	Is it true that no poisonous fish has ordinary scales?
	Yes, insofar as naturally poisonous fishes are concerned. Although a number of normally edible fish may occasionally become poisonous as a result of bacterial or other contamination, fish that are normally poisonous to eat belong to only a few groups, particularly the Order Plactognathi, which include the triggerfish, filefish, puffers, boxfish, porcupinefish. Although some of these are good eating, others are dangerously poisonous. A good rule to follow when determining whether a fish is edible or not runs as follows: No poisonous fish has ordinary scales such as are found on bass, snapper, or goldfish; instead they are covered with smooth, prickly, or thorny skin, rough or spiny scales, or hard, bony plates. The jaws of many of them have an enamel-like covering and resemble a gleaming white, turtle-like beak. Few of these poisonous fish have a regular fish shape; instead they are grotesque creatures with highly flattened or bony box-like bodies or other bizarre shapes.
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	Q&A 2.	Is the filefish edible?
	No. In fact, the filefish (also called foolfish, leather-jacket, or shingle fish) is frequently dangerously poisonous, though the extent of this may vary somewhat among the various species. Not only is the flesh poisonous, but also the liver, gall bladder, roe, and reproductive organs are capable of producing sudden illness if eaten. The filef1sh may be recognized by its extreme flatness, sandpaper-like skin, and sluggish movements when in the water. Fortunately it is also so bizarre and unpalatable in appearance that it is seldom, if ever, used for food. The filefish gets its name from the single flexible file-like spine on the top of its head, as well as from the rough skin.
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	Q&A 3.	Do poisonous food fish form a special biological group?
	Yes, generally speaking. While some fish may occasionally become poisonous through bacterial or other forms of contamination, the truly poisonous eating fish belong principally to the single Order Plectognathi. This Order contains the triggerfishes, filefishes, puffers or blowfish, porcupinefishes, trunkfishes, and the giant ocean sunfish, Mola mola. It should be remembered that while some Plectognaths are good eating a great number may be exceedingly dangerous - the liver, gall bladder, and ovaries being the principal source of the poison, which resembles that of deadly mushrooms in its action. Fortunately the Plectognaths are among the easiest of fishes to recognize, and their various bizarre shapes and coloring act as a natural "warning" to anglers.
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	Q&A 4.	Are all filefish poisonous to eat?
	Filefishes (Family Monocanthidae) are a flattened, slow-swimming, peculiarly shaped fishes with a long, movable spine on the head and skin with a sandpapery texture. Some of them are extremely poisonous to eat especially Alutera scripta, the scrawled filefish of the lower Florida coast on d the tropics. One species, the yellow leather-jacket of Australia (Nelusetta cittiata) is important food fish with white, well-flavored flesh, and it is reported that the common filefish (Monocanthus ciliatus) is eaten locally without ill effects. The liver and roe of these fish should always be avoided, since they may be highly toxic at times.
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	Q&A 5.	What is tetraodontoxin?
	This is the medical term applied to the poison found in the roe, liver, and gall bladder of certain species of puffers or blowfish, belonging to the Genera Tetraodon and Sphoeroides in particular. The flesh of these fishes is white, fine in texture" and flavor, and is frequently eaten or sold under the name "sea chicken". Great care should be taken in cleaning these fish, because of possible contamination from the viscera, and under no circumstances should the liver or roe be eaten. The common name “puffer” is derived from the fish's habit of inf1ating the stomach with air or water when alarmed. This makes them too large to be swallowed by other fish.
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	Q&A 6.	What is the difference between "poisonous" fishes and "venomous" fishes?
	"Poisonous" fishes are those whose flesh, when eaten, will produce sickness, while "venomous" fishes are those which inject their venom by means of spines, stings, or teeth. Hence, the words "poisonous" and "venomous" are not interchangeable, when considered from a scientific standpoint. In some instances a fish may be both "poisonous" and "venomous", since certain species (for instance some tropical surgeonfishes) are not only armed with venomous spines, but have poisonous flesh as well.
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	Q&A 7.	How do clams and oysters become polluted?
	Clams, oysters, and other shellfish sometimes become polluted in certain areas where there is an abundance of sewage or a large concentration of dinoflagellates. This pollution is due in the presence of sewage to the ingestion of poisonous bacteria. Poisonous dinoflagellates (single-celled animals) likewise may become concentrated within the gill cavities and livers of the mollusks. If the shellfish are removed to a "clean" area for a certain length of time, the poisons will be gradually lost and they will then become safe for eating. Prolonged cooking will also weaken the poisons, but this will not ordinarily make the shellfish safe to eat.
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	Q&A 8.	Are balloonfish good to eat?
	Most or all of the local species of "balloonfish" or puffers are edible so far as their flesh is concerned, and some are considered to have a very delicate flavor. Care should be taken that the flesh is not contaminated by the livers, gall bladders, roe, or other viscera, since these parts may in some cases be highly poisonous. The puffers (family Tetraodontidae) receive their common name from their ability to inflate themselves with either air or water when alarmed, causing the body to assume a nearly spherical outline. This habit protects them from their common enemies by making them too large to be swallowed if captured.
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	Q&A 9.	Several people have told me that filefish and triggerfish are good to eat, but others have said that these fish are poisonous. Can you tell me anything about this? Key West, Florida
	As far as is known, the Atlantic Ocean triggerfishes are safe to eat, and when properly prepared they make a very tasty dish. The filefish, however, should be left alone, and although many people maintain that the filefishes are of excellent flavor, some of the species in this family have been known to have poisonous qualities. The filefish can be easily told from the triggerfish by its one strong dorsal (back) spine as compared with the three spines in the triggerfish. Triggerfish can be prepared as most other fishes, but baked or broiled fillets are unusually palatable. When baked in a white cream sauce garnished with cheese, onion rings and mustard, triggerfish are indeed delicious.
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	Q&A 10.	Is the rabbitfish that we catch on party or “head” boat trips good to eat? Fort Myers, Florida
	The fish to which you refer is probably the smooth puffer Lagocephalus laevigatus. The species ranges widely along the Atlantic sea coast from Massachusetts to Brazil. Specimens have been taken measuring two feet in length. The common name rabbit fish comas from the eyes and the teeth, both of which resemble those of the rabbit. The flesh is widely eaten and it is said to be palatable and tender. There is a danger in eating the flesh from any of the puffers, however, since they are known to have caused violent poisoning. The exact nature of the poison is not understood, but is thought to have its origin in the gut and more likely, the liver. If the rabbit fish is to be eaten care must be taken that the flesh does not touch the internal organs. Cleanly cut fillets from freshly caught fish should be safe. The fillets should be thoroughly cooked to destroy any alkaloid chemicals present.
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	Q&A 11.	How can you tell if a barracuda is poisonous? New York City, New York
	A distinction must be made between fish which is poisonous due to spoilage and decomposition as a result of keeping too long without refrigeration, and the types of fish poisoning which are inherent in the flesh or organs of the fish itse1f even when completely fresh. Apart from tests of taste and smell, a simple test for spoilage is the condition of the gills which become slimy and lose their bright color, and the fitmness of the flesh which becomes soft if spoilage takes place. Under these conditions, the imprint made by a finger will remain in the flesh. Although the barracuda is usually perfectly safe to eat, in the West Indies there have been occasional reports of fish poisoning which is inherent in the flesh or organs no matter how fresh. Symptoms of this type of poisoning are nausea, vomiting, dizziness, numbness and cramps. There is no satisfactory way of determining whether the fish is poisonous, although in various parts of the West Indies it is believed erroneously that a silver coin placed in the pot during cooking will turn black when the fish is poisonous. Further information on poisonous fishes is given published by The Marine Laboratory and available upon a price of $.75.
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	Q&A 12.	Can you tell me whether the common toadfish or blow-fish is considered edible? We have tried them and found them to be so, but we have started many arguments about them since many people believe them to be highly poisonous. I know they will almost kill a cat if eaten raw. Does cooking destroy whatever poison they may contain? Titusville, Florida
	Unfortunately, common names are often applied to quite different species of fish. The fish to which you refer is probably one of the puffer fishes or tetraodonts. These fish inflate themselves and do have poisonous characteristics. Some of them are called toadfishes, but this name should be reserved for Opsanus tau, which does not inflate itself. The true puffer fishes have flesh which is attractive in appearance and flavor, and which is sometimes eaten. But the gall bladder, liver, roe, and intestines may contain a virulent poison. In some tropical species, the flesh is poisonous also. Since poison fishes have not been thoroughly studied, it is wise to follow local custom in eating the flesh.
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	Q&A 13.	One of my neighbors fed some raw blow-fish to his two kittens early in the evening and found the kittens dead the next morning. Is the blow-fish poisonous when eaten raw at this time of year? Miami, Florida
	Puffer, or blow-fish poisoning differs from poisoning due to other fishes in that the poison is not acquired through the food of the fish but originates in the fish itself. For this reason, it is dangerous all year round. Some of the internal organs of the fish are especially poisonous, although the flesh of at least some puffers is edible and regarded as a delicacy in some parts of the world. However, puffer poisoning is frequently fatal and it would probably be wise to avoid eating the fish or feeding them to pets.
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	Q&A 14.	I have been told by many people that the fish I call blow-fish are good eating, and yet others tell me that they are called puffers and are poisonous. The fish to which I refer inflate themselves like a balloon and have a skin like sandpaper. They also have teeth like a clamp and bite down on the hook when they are caught. Is there such a fish as the poisonous puffer? If there is, how does it differ from a blow fish? Also, which one is edible? Melbourne, Florida
	There is no question about the toxicity of puffers or balloon fishes. The poison is not found in the flesh, however, but in the viscera (especially the roe) and in the skin. Since most people do not eat these parts, they will tell you that the puffer is not poisonous. However, if the fish is not carefully cleaned, there is always the possibility of contamination of the muscle tissue with toxin from the viscera or skin. It is not possible to state which species of puffers are more poisonous than others; much work remains to be done on these fishes. Puffer poisoning is a distinct type of fish poisoning. Puffers apparently manufacture their own toxin and they are invariably toxic.
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	Q&A 15.	For many years, we have been catching blow-fish in the coastal waters from New Jersey to Massachusetts have eaten the meat of these fish and have found it to be both tender and delectable. Is there any chance of poisoning after blowfish are cooked? New York, New York
	There is no question about the toxicity of at least some puffers and porcupine fishes. Probably the toxicity varies with the species. The toxin appears to be concentrated in certain of the internal organs, especially the gonads and liver, and possibly also in the skin. The flesh of many puffers is nontoxic if uncontaminated by the poisonous organs during cleaning. Certainly it is eaten by many persons without harmful effect. In the United States the internal organs of fishes are rarely eaten, hence the number of cases of poisoning are few. In Japan, however, an average of about twenty persons die each year from eating puffers. The poisonous qualities are unaffected by cooking.
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	Q&A 16.	Recently we had a raw conch salad for lunch. I selected the conch myself-large, very white and with lively muscle reaction. Yet, my three children, two maids and myself became very ill after eating the salad. The doctor prescribed Allen & Hanbury's (England) "Guanimycin" tablets, which gave us immediate relief from the cramps and pains. There may have been a Samba conch in the lot but I understood the Samba flesh is rather yellow. Or the conch may have been washed in harbor water, but tests have shown very little pollution there. Nassau, Bahamas
	This is the first factual account received of poisoning from conch. Although we have heard that conch can be poisonous at times, we never believed it except in the case of the Samba. Lately, however, it has been learned that conch are herbivores and feed on very small filamentous algae. This makes it possible that they could eat blue-green algae, which Dr. Randall considers may be the possible source of fish poisoning in the tropics. Samba, easily distinguished by its nearly black skin, is presumed to be inedible, causing severe sickness when eaten.
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	Q&A 17.	In the Virgin Islands the natives are constantly warning that such and such a fish feeds on the "copper banks" and is poisonous, if eaten. I consider this nonsense but would like to hear your opinion. St. Thomas, Virgin Islands
	Unquestionably certain fishes, such as barracuda, amberjack, kingfish, several species of jack, some of the larger species of grouper and snapper, the hogfish and moray eel can cause severe poisoning at times, even when fresh fish are fully cooked. The incidence of fish poisoning, known as ciguatera in the Caribbean area, is low and poisonings tend to be localized. When toxic fishes occurred off a copper mine in Virgin Gorda; it was assumed that there might be banks of copper in the seas nearby and the copper from these banks was the toxic agent. It seems more likely that a unicellular plant, perhaps a blue-green alga, will one day be demonstrated as the organism producing ciguatera toxin. A more plausible explanation for toxic fishes off the Virgin Gorda copper mine is the new surface that was produced when rubble from the mine was thrown over the cliffs near the mine into the sea. This alga may be one of the first growing on new surfaces in the sea. An article is now being written for Sea Frontiers which will discuss ciguatera in greater detail than is possible in Sea Secrets.
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	Q&A 18.	I have read where people have been poisoned from eating barracuda. What causes the barracuda to be poisonous at times? New Orleans, Louisiana
	The agent that causes barracuda to be toxic is not known. However, considerable time and effort has been devoted to this problem and a lot of circumstantial evidence has been gathered. The toxin is not produced by the barracuda but is obtained through its habit of feeding on reef fishes. The toxin accumulates in predatory fishes, such as barracuda, amberjack, black grouper, et cetera, so that larger individuals are more toxic than the young. Reef fishes acquire the toxin in their diet. The most likely source it is thought at present is a one-celled blue-green algae that lives on the bottom.
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	Q&A 19.	Several of my patients attended the same dinner party and ate what presumably was a sea trout which was supposed to have been caught in the Gulf of Mexico. Several developed nausea, vomiting and diarrhea, and all developed numbness, tingling, itch and marked weakness. This was obviously a neurotoxin of some type. The material was taken to a laboratory, but no pathological organism was found. Apparently the neurotoxin was in the fish itself. Have you heard of such a thing occurring in sea trout? Also, does this seem similar to the type of neurotoxic effect observed after eating barracuda? Lake Worth, Florida
	The symptoms of your patients definitely seem to be a fish poisoning known as ciguatera. You refer to thefish as "presumably" a sea trout, and "supposed" to have been caught in the Gulf of Mexico. In a thorough survey of the literature, there is no reference to toxicity of sea trout or any other sciaenid fish. Furthermore, there are no cases of ciguatera reported from the Gulf of Mexico. There is, however, strong doubt that the fish eaten by your patients was a sea trout from the Gulf of Mexico. The fish which most often causes ciguatera in Florida is the barracuda. Other fishes with such a reputation, at least in the West Indies, are the amberjack and other jacks such as the horse-eye and yellowjack, kingfish, dog and Cuban snappers, black grouper, and the green moray eel. Usually only the very large individuals of any species are poisonous, and only a very few of these. Poisonous fishes are found around the reefs. The sea trout is not a reef fish. It lives primarily in brackish areas where ciguatera is unknown. All of the worst offenders in fish poisoning are fish-eaters. The sea trout feeds mainly on crustaceans. The fish that gave your patients ciguatera may have been a barracuda. It is illegal to sell barracuda in Miami, but many are sold by cutting them up and marketing them under some other name. If the fish your patients ate was larger than five or six pounds, and if it was cut in vertical sections and the steaks were nearly round in cross-section, this would constitute good evidence that it was not a Florida sea trout.
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	Q&A 20.	Could you furnish me information concerning the specific species of toadfish that are toxic, and the nature of the poison? Stuart, Florida
	I am uncertain what fish you have in mind when you use the term toadfishes. So far as known the true toadfishes are not poisonous, although they are rather repulsive. Perhaps you had in mind the puffers and their allies, many of which are poisonous. It is suggested that you look up the recent book by Bruce Halstead entitled Dangerous Marine Animals. This was published in 1959 by Cornell Maritime Press and should be available in many public libraries and through your local book dealers.
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	Q&A 21.	It is possible for a toxic fish to obtain toxin through inheritance? Queens Village, New York
	Scientists generally believe ciguatera, or fish poisoning, is produced by toxic materials accumulated by a fish during the course of its life. These substances are not transmitted to its offspring.
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	Q&A 22.	How can one distinguish edible from poisonous fishes? New Haven, Connecticut
	Unless you know by sight the species of fish which can be poisonous this is impossible, as there is no general distinction between the appearance of edible and poisonous fishes. An excellent description of poisonous fishes may be found in Dangerous Marine Animals by Bruce Halstead, which was published in 1959 by Cornell Maritime Press.
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	Q&A 23.	I have recently read articles about fish poisoning, called by the name ciguatera. What are the symptoms for diagnosis and what is the remedy? New York, New York
	The most reliable diagnostic sign for ciguatera is a peculiar sensory inversion whereby hot or warm objects feel cold and cold objects conversely may feel warm. There is almost always a tingling about the lips and tongue, associated with nausea, abdominal cramps, perhaps diarrhea and a profound sense of depression. Unfortunately, no single specific remedy has yet been discovered for the treatment of this condition. The most successful management of the disease has been accomplished by supportive and symptomatic treatment. It should be emphasized that the condition appears to be somewhat resistant to treatment, with the consequence that patients may be slow to respond and may experience symptoms over a somewhat protracted period.
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	Q&A 24.	For some time I have been eating barracuda speared in our area at least once a month or oftener when possible. Our health department has no record of barracuda poisoning and a marine biologist in the area feels that reported cases of poisoning by barracuda from the Florida Keys were simply due to decayed meat. At the same time commercial fishermen in this area insist that barracuda poisoning does exist, and they will have no part of eating barracuda. Could you please help solve this discrepancy by sending me any references to medical articles on the subject and your opinion with regard to the etiology of barracuda poisoning? Venice, Florida
	You have, to date, been fortunate. It is statistically probable that anyone who persists in eating barracuda, particularly the large ones, from a variety of localities will sooner or later experience the unpleasant symptoms of ciguatera. To maintain that the poisoning is the consequence of eating poorly preserved or inadequately iced fish is to fly in the face of much unequivocal evidence. Reference is suggested to reports of instances of ciguatera incidents by Dr. John Randall and described by him in the Bulletin of Marine Science of the Gulf and Caribbean and also in Sea Frontiers (Volume 7, Number 3) for August, 1961. Information on this subject is also available in papers by Dr. Banner and associates published in the Annals of the New York Academy of Science, Vol. 9'0, November 1960. This same journal describes some biological and chemical aspects of the toxins responsible for ciguatera in a paper written by Dr. Halstead and his associates. Information on barracuda poisoning is also contained in Studies in Tropical Oceanography, No.1, entitled “Systematics and Life History of the Great Barracuda," available from the University of Miami School of Marine Science. Price: $7.95. The consensus regarding the etiology of this condition places the blame upon the diet of the fish. One theory is that the barracuda ingests toxic material, contained in fishes upon which it preys. This toxin cannot be excreted rapidly enough to prevent its build-up in the organism. Somewhere in the food-web the prey fishes acquire some extremely virulent toxins, probably from marine algae, although this has not been established unequivocally. This material may be concentrated as it is passed up the food-web until the barracuda acquires a significant charge. Depending upon the fishes available for its food, the barracuda has a variable and completely unpredictable burden of toxicity when it is caught. It is impossible from tests or from the appearance or the behavior of the fish to identify the toxic ones.
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	Q&A 25.	A recent book I've read listed the rabbitfish as an excellent food fish and stated that it has some sort of poisonous sack. Can you tell me where this sack is located and how it can be identified? Would this same procedure apply to the blowfish which was also listed as an excellent food fish? Pompano Beach, Florida
	The rabbitfish is a member of a large group or order of fishes including puffers, triggerfishes, boxfishes and the filefishes. Most members of the group produce poison as a result of their everyday life activities. These systematic poisons are concentrated in the internal organs, especially the liver, kidneys and gonads. There is considerable variation in the degree of toxicity, depending upon species, season and locality. Puffers are used for food in many parts of the world, and as a result of improper cleaning of the fish, there are numerous cases of poisoning and a fair incidence of death. For this reason, no part of the puffer is generally recommended for use as food. The rabbitfish, a puffer of fairly large proportions, is a species most often eaten along the Atlantic seaboard. Apparently the flesh itself is not toxic, but with so many good fishes in the sea, why take a chance with one that might kill you? Puffer poisoning is severe and the incidence is high.
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	Q&A 26.	We have read of people dying from eating barracuda, which we understand is sometimes poisonous. Is this true of barracudas along the west coast of Africa? We have never heard of such a case here. Monrovia, Liberia
	To the best of our knowledge the various species of barracuda taken in your waters are never toxic. Possibly this is due to the absence of coral reefs and other ecological conditions for toxic plants to occur. (Toxicity in barracudas is believed to result from their eating herbivorous fishes which ingest toxic plants.) All our reports on poisoning in humans from eating barracudas have come from the tropical western Atlantic and from Indo-Pacific regions.
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	Q&A 27.	According to an article we recently read, blowfish are poisonous to eat. Many people, including myself, skin the back of this fish and remove two white tenderloins, one on each side of the spine. The quality and texture of this meat is similar to scallops. It is known by a variety of names, including "Chicken of the Sea." In many of the tide-water areas around the Chesapeake Bay it is considered a delicacy. Would you care to comment on the allegation that this fish is poisonous? Ellicott City, Maryland
	All blowfishes produce in their metabolic processes a poisonous substance. Some species are more poisonous than others. The poison is present in the internal organs, especially the liver, kidneys and gonads. To eat the tissues of these organs is to invite death. The subject of puffer poisoning (called Tetrodon poisoning) is discussed by Bruce Halstead in his book Dangerous Marine Animals, available from the International Oceanographic Foundation or your local bookstore. Two puffers are commonly eaten along the coast of the United States. One is the northern puffer, Sphaeroides maculatus, which is sold as sea squab or as puffer. The other is the smooth puffer, Lagodon laevigatus. The statement that poison results from carelessly cleaned fish is based on the fact that pieces of kidney and other poisonous organs may remain with the fish if one is not careful.
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	Q&A 28.	I have heard that fishes known as puffers are a delicacy. In a recent magazine article, however, the statement was made that puffers highly poisonous. Should we or should we not eat puffers that we catch? Metairie, Louisiana
	It is unfortunate that fishes as delicate in flavor as the puffers should be so poisonous. This is a widely distributed family with many Pacific species having been implicated in human deaths. Puffer, or Tetrodon, poisoning is the most virulent form of fish poisoning known. According to Dr. Bruce Halstead, who has assembled information on poisonous fishes from allover the world, the overall mortality for Tetrodon poisonings is about 60%. Puffers occur throughout warm and temperate seas. They are highly prized as food in Japan, and they even appear in the United States markets at times. However, in Japan during the 10-year period ending in 1937, over 900 deaths were recorded from Tetrodon poisoning. From 1949 to 1951 nearly 400 cases were recorded with a mortality of 51 %. Tetrodon toxin from Pacific species has been studied extensively. It has recently been characterized chemically. Less information is available on the poisonous qualities of Atlantic puffers, but Dr. Edward Larson of the University of Miami has studied the toxicity of the common Atlantic puffer, Spheroides maculatus. Although Dr. Larson reports that the toxicity of puffers from the Miami area was not as great as from other east coast locations studied, local puffers were sufficiently toxic to cause two recent deaths in Miami. According to Dr. Larson, the most toxic portion of the Florida fish is the skin, followed by the liver and gonads. We recommend that puffers not be eaten.
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	Q&A 29.	While cruising the British Columbia waters of Georgia Strait in July, 1965, I was warned that there had been a “red tide,” and that therefore the clams were dangerous to eat. I was also told that oysters were not affected and so could be safely eaten. Are only clams affected by the red tide, or are oysters also rendered poisonous? Tucson, Arizona
	It is dangerous to eat mussels, clams or oysters in areas known to be having outbreaks of red tide. These bivalve mollusks are filter feeders; that is, they pump water through their gills and strain out small particles of food. If some of the food contains the minute organisms that are the cause of the poisoning, persons eating the shellfish could become seriously ill. Mussels, for example, can store great quantities of poison before they are killed. When eaten by man, these mussels can cause paralytic shellfish poisoning. There are many reported cases of outbreaks of shellfish poisoning. The red tide occasionally occurs off Florida's west coast. This phenomenon is caused by a "bloom" of a microscopic animal named Gymnodinium breve. Occurring in sufficiently dense numbers, they reduce the oxygen content of the water and cause an irritating gas when they die and decay. The water may become "rosy" due to the enormous numbers. In coastal waters of west Florida the organism is always present, but under normal conditions no more than 1,000 animals will be found in a quart of water. During intense blooms, however, as many as 60,000,000 of these dinoflagellates may be found in a quart of water. A similar red tide, caused by a related organism, has occurred off California. Yellow-water blooms have been reported off Vancouver Island, British Columbia. In the western Pacific and Indian Ocean red tides have been caused by a microscopic alga.
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	Q&A 30.	In Sea Secrets for May, 1966 (Vol. 10, No.5) it is suggested that one can contract hepatitis from raw clams, and that cooking them does not eliminate the danger. Would this also apply to raw oysters, cooked oysters and steamed mussels? St. Louis Missouri
	Clams, oysters and mussels are all filter feeders. In certain marine areas these mollusks accumulate the unicellular organisms responsible for "red tides" and thus acquire a virulent toxicity. This accounts for the common practice of Public Health agencies to close certain areas to clam digging at certain times of year. Another aspect of bivalves' feeding mechanism is the ability to concentrate various particles from sewage, resulting in the transmission of infectious hepatitis to man. The activity of the virus may be somewhat attenuated in cooking, but there appears to be some question about the effectiveness of this method of "purification." Unless one knows that the region from which his shellfish came is free of sewage pollution, he might be wiser to avoid eating clams, oysters and mussels.
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	Q&A 31.	I recently read a newspaper article stating that the blowfish was excellent table fare, if you did not eat the liver or roe. Is this true? I thought the whole fish was poisonous. Baltimore, Maryland
	Your question is one that has long puzzled biologists. It is not known whether the northern blowfish in your area is the same species as the ones in the south. Also, we do not know whether the blowfish toxin results from the animal's food, which may not be the same in the north and the south, or whether it is produced by reproductive activity. The latter is the case with the poisonous blowfishes of the Indo-Pacific area. In these Indo-Pacific species, the liver, flesh, skin, gonads, stomach, and other parts of the fish are poisonous; the degree of toxicity, however, depends on the stage of gonadal development. A further discussion of toxic blowfishes will be found in Dangerous Marine Animals by Bruce W. Halstead, Cornell Maritime Press, Cambridge, Maryland, 1957.
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	Q&A 32.	A well-known surgeon who has spent a lot of his time in the arctic regions has told me that the liver of the polar bear is so high in vitamin A that it is poisonous to humans as food. He assumes too that all animals of that region, including the natives, have a high vitamin A content and thus have better vision in the brighter sunlight. Dunedin, Florida
	It is quite true that the polar bear liver in general contains so much vitamin A as to render it poisonous to man. The same high concentration is also found in the liver of the seal. Both of these animals are carnivorous. The vitamin A represents the excess they have ingested over their metabolic requirements. In these animals, as in some sharks, the liver appears to be a storage depot in which excess vitamin A is sequestered. Arctic sunlight is not brighter than in lower latitudes and excess vitamin A probably doesn't improve daylight vision perceptibly.
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	Q&A 33.	At the present time the commercial fish importing industry is in a state of chaos as a result of the Food and Drug Administration's action with respect to mercury. There appears to be a great difference of opinion concerning the value or danger of mercury and mercury compounds. There does not seem to be any firm scientific evidence with respect to what level and what form of mercury is dangerous. Could you shed any light on the subject? Bronxville, New York
	The general consensus is that the amounts of mercury reported by various organizations have been substantially correct. It is also agreed that any form of mercury can be converted to methyl mercury by the action of bacteria. The limits appear to be quite low considering the quantities of fish that would normally be eaten. However, it is presumed that these limits have been set so that even a person on an exclusively fish diet could not be harmed. There is no question that there has been an intemperate approach to this whole problem on the part of some of the news media. The actual cases of mercury poisoning have apparently been very few and these few have been in restricted areas where heavy industrial poisoning has taken place. Our information is that industry has done a good job in cleaning up the situation. In an attempt to put the known facts into the proper perspective, we are trying to get an oceanographic chemist and a pharmacologist to join in writing an article for Sea Frontiers on the whole subject.
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	Q&A 34.	Can you tell me the test procedure for determining the amount of mercury in fishes? Redlands, California
	At present, we do not know of a simple home test for mercury in fishes. Tests for mercury in salts are not difficult, but when it becomes a part of the animal tissue, there are two main problems: (1) the quantity of mercury involved is very small and (2) the organic material of the tissue makes it difficult to get at. Mercury analyses in animal tissue have received considerable attention recently. The first step usually consists of destroying the organic matter, but here special precautions must be taken to prevent the loss of mercury by volatilization. This can be done in many ways, but it is usually by wet oxidation using a 1:1 mixture of nitric and sulfuric acids. Next, the mercury is isolated. This is done many times by extracting with dithizone in chloroform. The resultant color can be measured directly in a spectrophotometer. Another way is to reduce the mercury to elemental mercury and measure it by flameless atomic absorption spectrophotometry. This is the method that is prevalent. A reference on this procedure is "Determination of Intact Phenyl mercury Compounds in Animal Tissue" by Miller, Lillis and Gzonka, published in Analytical Chemistry, 30:1705 (1958). A simple test for mercury in a salt is to place a mixture of mercury salt (like the ashes from a dry combustion) and sodium carbonate (sal soda) in an ignition tube and heat it. Mercury vapor will be evolved and will condense in the upper portions of the tube in the form of a silvery white mirror.
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	Q&A 35.	When testing for mercury in fish, is the entire fish ground up and then tested, or are the entrails separated from the fish, or is the edible flesh tested separately? Jamesport, New York
	The entire fish is not ground up when mercury tests are carried out. The organs are tested only for special studies, but many tests contrasting mercury content in the muscle, liver and brain have been made. For mercury-level tests, only the meat or edible flesh is utilized. The general procedure used to carry out these tests is described in question #2879 in the September-October, 1971, issue of Sea Secrets.
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	Q&A 36.	The enclosed fragment of a metallic-looking substance was taken from the stomach of a 21/2-pound hind caught in our waters. Fragments of this type have also been found in the flesh and heads of groupers. I have been told that these fragments must be removed before cooking the fish as they are poisonous, and recently some people had to be hospitalized after eating grouper without removing them. Can you tell me what the fragment is? Montserrat, West Indies
	The metallic-looking substance that you sent to us is actually the fin spine of some species of marine fish. Its metallic appearance is due to the fact that it is still covered with a thin layer of tissue. The fin spines of at least 40 species of bony fishes have poison glands associated with them. Catfishes, toadfishes, and scorpionfishes are some of the better-known ones with poisonous spines. This does not mean, however, that the spines found in groupers and hinds are from poisonous fishes. The spines of nonpoisonous fishes might cause an infection in the flesh of the larger fish in which they become embedded, leading to the formation of substances that are toxic to man. It is also possible that the illnesses reported to you were due to ciguatera poisoning, which results when large carnivorous fishes feed on toxic reef fishes. Several large groupers, notably the black grouper and yellowfin grouper, are notorious in this regard.
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	Q&A 37.	I am enclosing a list of shell-bearing molluscs from the Florida Keys. Can you tell me which are edible by man? Key West, Florida
	In all probability, all of those species listed by you are edible. Advice concerning the edibility of molluscs, however, must be dispensed and accepted with caution, for even those species that are usually eaten may at times be poisonous. This is especially true of certain bivalves that have ingested large quantities of certain toxic, microscopic dinoflagellates when the latter are unusually abundant. In addition, in polluted areas, bivalves may harbor human pathogens. The "samba" conch, which is just an advanced-age form of the edible pink conch, Strombus gigas, is reported to be poisonous sometimes. The West Indian top shell or "whelk," Cittarium pica, is very commonly eaten by humans; but ciguatera, the often-used name for fish poisoning, is derived from this top shell's Cuban name cigua. It, too, has been reported as poisonous, although there appear to be no recent records of such poisoning. Although some may be edible, the opisthobranch molluscs, especially the nudibranchs, should be avoided, for some accumulate the toxins of their prey and some may also secrete noxious substances. Further information may be found in Catch and Cook Shellfish by Dorothy Raymond (Great Outdoors Publishing Company, St. Petersburg, Florida, 1973), Stalking the Blue-Eyed Scallop by Euell Gibbons (David McKay Company, New York, 1970), Dangerous Marine Animals by Bruce W. Halstead (Cornell Maritime Press, Cambridge, Maryland, 1959), and the forthcoming Guide to the Larger Marine Gastropods of Florida, the Gulf of Mexico, and Caribbean Region, edited by G. L. Voss (Sea Grant Field Guide Series No.5, University of Miami, Coral Gables, Florida).
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	Q&A 38.	The clams and oysters of Sarasota County waters are inedible because of pollutants. I have heard that they can be purged by keeping them in a wide-mesh metal basket in Gulf of Mexico waters. If so, how long does this process take, how deep must the water be, and can they be stacked in the basket or must they be in a single layer? Sarasota, Florida
	In many parts of the world, the law requires that all bivalve mollusks (oysters, clams, mussels, and scallops) must be allowed to circulate cleansed water through their respiratory and digestive systems, before they are sold for consumption. In this way, they are able to release the bacteria and viruses that are potentially dangerous to humans. This purging, or depuration, is critical if the mollusks are to be consumed raw or will not be cooked thoroughly. The length of time required for depuration depends on the degree of pollution of the waters from which the bivalves were originally taken. In Spain, for example, mussels are placed for 48 hours in seawater that has been sterilized by chlorine and then aerated. If there is considerable residential-waste pollution released in the area of the oyster beds, it may take a number of days of depuration before they would be safe for raw consumption. It is best, however, to entirely avoid eating any bivalves taken in areas that are close to population centers or industrial developments. Since metal may corrode, the container for holding the bivalves during depuration should preferably be constructed of fishing net material or plastic netting. Stacking the bivalves will not affect the process. Sediment-free, clear waters several miles offshore in the Gulf of Mexico would probably be best; as long as they are clear, the depth is not critical. One should also keep in mind that any disturbance, such as the vibration of a boat's motor, may cause the animals to close their shells and stop filtering, thereby bringing 1he depuration process to a halt.
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	Q&A 39.	Is it safe for me to eat meals containing raw fish caught near the southwest pass of the Mississippi River? New Orleans, Louisiana
	All estuarine fishes should be avoided in the preparation of dishes using uncooked fish. These fishes are especially subject to a wide variety of parasites, some of which could infect humans. In addition, they are more likely to feed in polluted areas and take up pesticides, heavy metals, etc. in their tissues. Croakers, which make an excellent seviche, congregate around sewage outfalls, at least in some areas. Anyone who wishes to eat raw fish will have less chance of endangering his health if he chooses open-ocean species such as tunas or dolphins. Even these species may be hazardous to eat raw, however. Several hundred cases of herring worm disease, or anisakiasis, have been reported world-wide during the last decade. The parasite causing this disease is killed by normal cooking or freezing, but usually not by light smoking of the fish.
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	Q&A 40.	It is customary in Bahamian and West Indian villages to keep conchs, beneath the docks. Many of these harbors have limited inflow and outflow and, at the same time, are populated with visiting yachts which discharge waste into the harbor. Why is the incidence of hepatitis so low from eating raw conch so exposed to human waste? Does the conch's lack of a filterfeeding mechanism make it less susceptible to picking up the virus? Virginia Beach, Virginia
	Since conchs are not filter feeders, they do not concentrate disease organisms in the way that filter feeders, such as clams, do. Pathogenic microorganisms can, however, adhere to the outside of the animals, and conchs taken from polluted waters should, therefore, be carefully washed in clean seawater before they are eaten. In some villages, the local inhabitants apparently build up an immunity to diseases to which they regularly come in contact. On the other hand, visitors to the same area may become very ill by eating polluted molluscs. A good general rule is to avoid eating seafood from any area suspected to be polluted.
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	Q&A 41.	I frequently scuba dive near the Miami and Hollywood sewage outfalls. Is it safe to do so, or to eat fishes or lobsters caught near them? Hollywood, Florida
	While many divers do dive near such outfalls, each risks an infection of some kind. While in most cases (though not all) the sewage is treated to some degree, this treatment does not necessarily rid the waste of all the pathogenic viruses and bacteria. Because of this, most scientists advise against diving such areas. If you continue to do so and wish to eat lobsters and fishes from the areas, be sure to cook them very thoroughly to kill any disease organisms. The effects of these outfalls on the marine life near them is not precisely known, but studies at the University of Miami are planned to determine this.
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	Q&A 42.	Is the roe of the black, long-spined sea urchin found in Florida and the Caribbean edible? New York, New York
	Gonads of the sea needle (Diadema anti/larum) may be poisonous to eat. According to Dr. Bruce W. Halstead, toxicity in sea-urchin roe appears to fluctuate from place to place and time to time. It is suspected that, if the algae that the sea urchin is feeding on is toxic, the poison is passed on to the sea urchin and may be concentrated in the gonads. Dr. Halstead cautions that tropical sea-urchin gonads should be looked upon with suspicion, regardless of the species, unless known to be nontoxic. The gonads of many different species of marine organisms, including fishes, are frequently found to be toxic. It is safer to be cautious than foolhardy, since many of the marine biotoxins are potent neurotoxins. On the other hand, sea urchin gonads are used as food in Barbados, in the West Indies.
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	Q&A 43.	Is there any way to tell if a fish contains the poisons that cause ciguatera prior to eating it? Atlanta, Georgia
	It is virtually impossible to determine in advance whether or not a fish contains ciguatera toxin, except by biochemical assay of its flesh. One can, however, take some simple precautions. Ciguatera, a phenomenon of the tropics, appears to be localized. Not all coral reefs are toxic, and even those that are may be dangerous only in certain areas. By talking with local fishermen, one can learn which areas are toxic and which species are dangerous, prior to a fishing expedition. If no information is available, it is wise to restrict yourself to eating only the small fishes, 3 pounds or less, in your catch. Bahamians are known to test the toxicity of a fish by feeding a cat a piece of it, and then observing the animal's behavior closely for 12 to 24 hours. Some "folk tests" which are ineffective and should be avoided are cooking a silver coin with the fish (if the coin turns black, the fish is toxic), and placing a piece of fish on an ant hill (if the ants eat it, the fish is "supposedly" nontoxic). Dr. Donald P. de Sylva and graduate student Mark Poli of the University of Miami's Rosenstiel School of Marine and Atmospheric Science (RSMAS) are attempting to determine how many cases of ciguatera can be traced to eating Florida reef fishes and whether or not environmental changes on coral reefs may be a contributing factor. These researchers would appreciate hearing from members who have had ciguatera, and may be reached by mail at RSMAS, 4600 Rickenbacker Causeway, Miami, Florida 33149, or by telephone at (305) 350-7220 or (305) 350-7334.
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	Q&A 44.	In Sea Frontiers and in Sea Secrets, it was suggested recently that pieces of fish flesh be fed to a mongoose or a cat to test the fish for ciguatoxin. Would it be advisable instead to feed the test animal a piece of the fish's liver, which would be expected to concentrate the toxin? Also, what quantity should be given to the test animal, without inducing needless illness? New York, New York
	While it is true that ciguatoxin will be concentrated in the liver of ciguatoxic fishes, it is not a good test for ciguatera to feed a piece of liver to a test animal, for the following reasons. First, the muscle of the fish is the site of the lowest concentration of ciguatoxin, and detection of a high level of toxin in the liver would not automatically signal a toxic level in the muscle. Thus, while a toxic liver might not be eaten without danger of illness, the flesh of the same fish could still be edible. Second, fish livers filter out and store all kinds of toxic materials, including pesticides, heavy metals, industrial pollutants, and natural compounds; therefore, if the test animal becomes sick from eating the fish's liver, it will be difficult to determine if the cause was ciguatoxin or some other toxic material. Sensitivity to ciguatoxin varies among people, and the same may be true for cats and mongooses. Therefore, in regard to the quantity of fish flesh that should be fed to the test animal, perhaps the best suggestion would be a piece that is in the same proportion to the animal's body weight as a dinner-sized portion would be to the body weight of the prospective diner. If the test animal is given too small a piece, it may not show the symptoms that would affect a human who had eaten a large meal of the same fish.
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	Q&A 45.	After reading question 3523 in the May-June issue of Sea Secrets, would like directions on processing eggs from fishes I catch for use as caviar and bait. Where is this information available? Salem, Oregon
	Processing directions are given in Marine Brief 16, Fish Eggs for Caviar and Bait, available from Marine Advisory Programs, University of California, Davis, California 95616. One should keep in mind that the gonads of puffers and certain other fishes are poisonous. In Poisonous and Venomous Marine Animals of the World, Dr. Bruce W. Halstead cites reports of toxicity, in the United States, for the alligator gar, cabezon and sea catfish and, in Europe and/or Asia (particularly during the reproductive season), for certain species of salmon ids, pikes, minnows, carps, catfishes, and pricklebacks.
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	Q&A 46.	Can escargot be prepared from marine snails? Berkeley, California
	Yes; however, true escargot generally refers to the European land snails of the genus Helix. Because land snails are known to harbor parasites that are dangerous to humans, they must be thoroughly cooked. Marine species used in escargot recipes include moon snails and whelks; however, one should check with local health authorities before harvesting these species. Moon snails and whelks often feed on bivalves which, in areas of dinoflagellate blooms, are, carriers of the toxin that can result in paralytic shellfish poisoning in humans. Snails are highly perishable. Whether fresh or from an open can, they should be used immediately. Several recipes for escargot are given in Molluscan Melange by Captain Alex Roth, Jr. (Aljemasu Enterprises, P.O. Box 7867, Tamuning, Guam 96911).
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