Mercury in Several Species of Billfishes Taken Off 

 Hawaii and Southern California 



RICHARD S. SHOMURA 1 and WILLIAM L. CRAIG 2 



ABSTRACT 



The results of analyses of the mercury content of 37 blue marlin, Makaira nigricans, 56 striped 

 marlin, Tetrapturus audax, and 3 swordfish, Xiphias gladius, are presented. 



The levels of total mercury found in white muscle of blue marlin caught in Hawaiian waters ranged 

 from 0.19 ppm to 7.86 ppm; fish specimens ranged in total weight from 96 pounds (43.5 kg) to 906 pounds 

 (410.9 kg). A trend of increasing mercury level with increasing size of fish was noted. The mercury 

 content in the livers of 26 blue marlin specimens examined ranged from 0.13 ppm to 29.55 ppm; there was 

 no apparent trend noted between mercury content in the liver and size of fish. 



Striped marlin from Hawaii and southern California showed a range of mercury levels in white 

 muscle of 0.09-1.09 ppm for the 14 Hawaii samples examined and 0.03-2.1 ppm for the 42 California 

 samples examined. The range in size of fish was 56-139 pounds (25.4-63.0 kg) and 109-231 pounds 

 (49.4-104.8 kg) for the Hawaii and California samples, respectively. From the wide spread of mercury 

 levels encountered in striped marlin, a trend of mercury level w ith size of fish could not be easily detected. 

 Livers of nine specimens from the Hawaii catch were analyzed; mercury levels ranged from 0.05 ppm to 

 1.53 ppm. 



Three swordfish weighing 6 pounds (2.7 kg), 100 pounds (45.4 kg), and an estimated 500 pounds 

 (226.8 kg) contained mercury levels in white muscle of 0.04, 1.71, and 2.10 ppm, respectively. 



In early December 1970 the news media stunned 

 the nation, particularly the fishing industry, with 

 the release of stories that some canned tuna and 

 swordfish steaks contained mercury in excess of the 

 Food and Drug Administration (FDA) interim 

 guideline of 0.5 ppm (Bernstein, 1970: Fleming, 

 1970; Los Angeles Times, 1970; Coffey, 1971). 

 Prior to State University of New York Professor 

 Bruce McDuffie*s discovery that mercury levels in 

 two cans of tuna exceeded the FDA guideline, the 

 problem of mercury in fishes was thought to be 

 localized and confined to freshwater fish species. 

 The high levels of mercury in freshwater fishes 

 were attributed to dumping of waste products into 

 waterways. 



A review of the literature undertaken at the time 

 of the announcement of mercury in tuna and sword- 



'Tiburon Fisheries Laboratory, National Marine Fisheries 

 Service. NOAA, Tiburon. CA 94920. 



-California Department of Fish and Game. Long Beach, CA 

 90802: present address: Southwest Region. National Marine 

 Fisheries Service. NOAA. Terminal Island. CA 90731. 



fish revealed a wealth of information related to 

 mercury and its toxic properties; references were 

 primarily of incidents occurring in Japan and Swe- 

 den. Despite the wide range of available informa- 

 tion, there was a conspicuous lack of data related to 

 mercury levels in living organisms in the marine 

 biosphere. For this reason the National Marine 

 Fisheries Service embarked upon an extensive 

 program early in 1971 to collect tissue samples of 

 marine and estuarine fishes and invertebrates for 

 analysis of mercury and other heavy metals (Com- 

 mercial Fisheries Review, 1971). 



Primarily because of their recreational value, the 

 California Department of Fish and Game collected 

 samples of striped marlin, Tetrapturus audax, and 

 albacore. Thunnus alalunga, for mercury analysis 

 during the summer of 1971. 



Our purpose in this paper is to provide the results 

 of analysis for total mercury content in samples of 

 striped marlin, blue marlin, Makaira nigricans, and 

 swordfish, Xiphias gladius. We will simply present 

 these data with some brief comments of the more 



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