ANNEX 9 



Status of Mercurv Studies in Hawaii 



by 



Richard A. Marland 



Interim Director 



Office of Environmental Quality Control 



The State of Hawaii became concerned with the methylmercury in fish 

 products in the month of April last year. By May of last year we had con- 

 ducted sufficient analyses under the auspices of the State Department of 

 Health to show that the average total mercury content of marlin entering the 

 market in Hawaii was just over 4 ppm. These results were corroborated by the 

 laboratory which Ms. Shultz represents here, the Pesticide Study 

 Laboratory. At that point we asked the fishing industry of Hawaii to withhold 

 sale of the blue marlin on a voluntary basis. This has been done ever since the 

 request was made. It was only fair that having had this kind of cooperation 

 from the fishing industry, the State of Hawaii should exert all possible efforts 

 to establish whether removal of this species from the market was justified or 

 to establish the conditions under which it could be sold. The Pesticide 

 Laboratory of the L'niversity has been conducting analyses to determine the 

 extent to which methylmercury is present as part of the total mercury value. 

 There are two other efforts now going on, sponsored by the State. One of them 

 is of such size and importance that we have requested funding from the 

 National Science Foundation. We have not yet had an affirmative response, 

 but this would be a 3-yr study at a cost of over $500,000. It will include the 

 evaluation of some 9,000 people in Hawaii who are known to have a fish- 

 eating habit. You've heard Dr. Kolbye point out that one serving of fish on 

 the order of 7 ounces per week at 1 ppm gives you a full week's quota of 

 methylmercury. If you're talking about a fish of 4 ppm, you get down to 

 something under 2 ounces a week. It is not unusual for people of Japanese 

 ancestry in Hawaii to eat a third of a kilogram of fish a day. On this basis it 

 becomes very important that the fish being consumed to that extent does in- 

 deed contain the lowest possible levels of organic mercury. So the study of 

 these 9,000 people of Japanese ancestry would be conducted as an historical 

 study to determine if there is any evidence in their medical history of an 

 effect of mercury poisoning. There would also be another study of some 300 

 people of Japanese ancestry. This 3-yr study will involve a very careful 

 monitoring of the diet of these people, examination of their medical history, 

 and observations made by physicians. The participants would all be 

 residents of Lanai; they are already being studied for medical deficiencies. 

 This study, which is an extensive study planned for 3 years' duration, has not 

 yet been started because the cost of the project cannot be met at the local 

 level. 



Recognizing that we might not be able to get a human epidemiological 

 study mounted immediately, the University of Hawaii, Department of 

 Animal Sciences, started a program of research in the winter in which they 

 used swine as an experimental animal. Swine, in this case, is an excellent 

 animal because the metabolic system of swine is almost identical to that of 

 human beings. There are some preliminary data available now from this 

 swine-feeding experiment. Substantially there were five groups of swine, one 

 on a control ration of feed, another on normal feed plus 1 pound of raw fish a 

 day, and three experimental groups in which this 1 pound of fish had added 

 mercury of 0.5 ppm, 5.0 ppm, or 50 ppm. These pigs were again subdivided 

 because of the interesting results coming from Ms. Shultz's work so that we 

 had half of them on organic mercury and half of them on inorganic mercury. 

 Not too surprisingly, of those pigs that were receiving 50 ppm of organic mer- 

 cury, or methylmercury, none lived past 26 days. They were the only pigs on 

 trial that died during the experiment . Pigs that were fed 50 ppm of inorganic 

 mercury showed liver damage and lymph node damage, and as yet we have 

 not conducted the pathological examination of these tissues so we do not 

 know if there was further damage. Pigs that were fed 5 ppm of organic mer- 

 cury in marlin appeared perfectly normal. Upon slaughter, hemorrhage on 

 the periphery of the lymph nodes was noted, the lymph nodes were enlarged, 

 and the livers had developed fatty tissue above them. There seemed, 

 therefore, to be some gross pathology in the pigs that were fed marlin with 5 

 ppm of organic mercury. Pigs fed 5 ppm of inorganic mercury showed no 

 symptoms or any type of pathology other than perfectly normal growth. 

 Those that were fed the lowest level were perfectly normal, even in the case of 

 0.5 ppm organic mercury. The reason for selecting these levels, of course, is to 

 establish, as Dr. Kolbye has pointed out, the validity of a 10-fold safety fac- 

 tor. Dr. Kolbye will be pleased to hear that from each of these trials two of the 

 females are being retained for breeding purposes and they will be studied for 

 three generations to see whether or not there is a placental transfer of mer- 

 cury to the offspring. These experiments, we hope, will lead to some type of 

 recognition of the hazard of mercury. We hope the human epidemiology ex- 

 periment will lead to some type of recognition of the risk, these data again to 

 form a base upon which decisions can be made. We wish that we could say at 

 this time that the data are sufficient to make decisions; they are not. We 

 don't know whether there will be sufficient data. We hope, of course, it will be 

 soon. 



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