TRACE ELEMENTS IN THE HAIRS OF WINTERING MEMBERS OF THE 13TH JAPANESE ANT ARCTIC RESEARCH EXPEDITION. Hiroshi KozuKA * and Yukio KANDA *

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1 64 TRACE ELEMENTS N THE HARS OF WNTERNG MEMBERS OF THE 13TH JAPANESE ANT ARCTC RESEARCH EXPEDTON Hiroshi KozKA * and Ykio KANDA * Abstract: The concentrations of six trace elements, Hg, A, C, Zn, Sb and Br, in the hairs collected from 10 members of the wintering party of the 13th Japanese Antarctic Research Expedition ( ) dring their stay in Antarctica, were measred by netron activation analysis. The mercry concentration in the hair decreased and its distribtion range became narrower dring one year-long stay in Antarctica. And its concentration increased and scattered over a wide range again after the party members retrned to Japan. The extremely high concentration of antimony sggests that the hair was contaminated by enviromental polltion on board the icebreaker Fn. No obvios trend was fond in the concentrations of other elements dring the stay in Antarctica. 1. ntrodction Netron activation analysis is the most sefl method for the determination of trace elements in biological samples, becase of its sensitivity, specificity and nondestrctive natre. This method has revealed the accmlation of poisonos elements sch as mercry and arsenic into the hair by metabolic processes. A representative work in this field was the analysis of arsenic in Napoleon Bonaparte's hair performed by FoRsHFvo et al. (1961, 1964). Their reslts indicated that he was probably poisoned by arsenic. Also, the mercry content in the hair is an important indication of its intake by the hman body. A great many investigations of the mercry content in the hair have been performed, especially by Japanese researchers, in view of the increasing national concern for the environmental polltion by mercry. The environmental research in Antarctica was planned by the Japanese Antarctic Research Expedition since The measrement of trace elements in the hair samples collected from the members of the wintering party was adopted in this new project, and the athors were entrsted with the task of measrement. * National Research nstitte of Police Science, Sanban-cho, Chiyoda-k, Tokyo.

2 Trace Elements in the Hairs of Wintering Members of JARE Experimental 2.1. Sampling of hair and washing of the samples The hair samples, obtained by sal hair-ct, of O members of the 13th Japanese Antarctic Research Expedition ( ) were collected once before the departre, three times dring the stay in Antarctica, and one after the retrn. The hair was washed to remove most of the adhering dst and oily sbstance by the following procedres : One gram of the hair was taken into a 200 ml separating fnnel, and 100 ml of 2% (v/v) nonionic detergent soltion (polyethylene sorbitan mono-oleate) was added. After shaking for 5 mintes mechanically, the detergent soltion was removed and then hair was washed three times with 100 ml of deionized water. Finally, the hair was washed with ethanol-acetone (+ ) mixtre soltion and dried at room tempetatre Standard soltion The standard soltions of Hg, A, C, Zn, Sb and Br were prepared by dissolving HgC 2, HAC1 4 4H 2 0, CS0 4 5H 2 0, ZnC0 3, C 2 H 4 (0HMCOOK) COOSb l/2h 2 0 and KBr into deionized water or acid soltion, respectively. The concentration of all these standard soltions was mg/ml Sample preparation and irradiation The hair sample of 500 mg was pt into a small polyethylene bag, which was then heat-sealed. Each standard soltion was prepared by pipetting an aliqot of its standard soltion on a filter paper (1 x 1.5 cm) with a microsyringe and drying it careflly nder an infrared lamp. Their contents were as follows : Hg : 5 pg, A : pg, C : O pg, Zn : 200 pg, Sb and Br : O pg. Each standard sample was packaged into a small polyethylene bag. The hair samples and the standard samples were packed together and irradiated in the HTR reactor (Tokyo Atomic ndstrial Research Co., Ltd.) for 5 hors at a flx of 2.1 x n/cm 2 sec, or in the TR GA reactor (nstitte for Atomic Energy, Rikkyo University) for 5 days (6 hors/day) at a flx of 5 x 0 11 n/cm 2 sec Chemical procedre and conting The irradiated hair was transferred into a 100 ml conical beaker, and 5 ml of concentrated nitric acid was added. The hair was decomposed on the hot-plate. The soltion obtained by decomposing the hair was dilted with deionized water to abot 6 N nitric acid soltion and the soltion was then

3 66 Hiroshi KozKA and Ykio KANDA passed throgh a HAP colmn (hydrated antimony pentoxide, 0.5 g, 0.8 cm x 10 cm). The efflent was pt into a polyethylene bottle and its r-ray spectrm was measred. By passing the sample soltion throgh a HAP colmn, 24 Na, which is a prevailing isotope in the irradiated hair and interferes the measrement of r-ray spectra of other isotopes, wa completely removed ( GRARD, 1968 ). Therefore, the contents of six elements were determined simltaneosly by r-ray spectrometry withot frther chemical separation. The r-ray spectrm of sample was measred with a 48 cm 3 Ge(Li) detector (FWHM : 4.0 kev at 1332 kev) eqipped with 4096 channel plse height analyzer. The amont of each element was determined from the ratio of the Table 1. Properties of nclides observable in irradiated hair with Ge (Li) detector. Element Nclide Half time (hr) Photopeak for determination (kev) C G4C Zn G9mzn Br 8 Br Sb 122sb A 19sA Hg 191Hg a:i C: C: t1.c tljn 10 Fig Channel nmber 2000 Gamma-ray spectrm of an irradiated hair sample taken with 48 cm 3 Ge (Li) detector. 3000

4 Trace Elements in the Hairs of Wintering Members of J ARE 67 peak area of the sample spectrm to that of the corresponding peak m the simltaneosly irradiated standard sample. The properties of nclides sed for determination m this work are shown in Table 1. Fig. 1 shows a representative r-ray spectrm of the irradiated hair sample. 3. Reslts and Discssion t has been considered that the trace elements are introdced into the hair by metabolic processes and adsorbed on the hair by external contamina- 10 p i C.Q "Ee l!j Q. g a. 0 5 Sep Mar. Jly Mar Sep. ---o ()-- ---<)--- Fig. 2. Sbject <> e e e Variation of mercry content in the stay in Antarctica. Sbject hair dring

5 68 Hiroshi KoZUKA and Ykio KANDA Table 2. Content of mercry in hair of the wintering members of the 13th Japanese Antarctic Research Expedition. Period of Range Mean Std. Dev. collection (ppm) (ppm) (ppm) Sept Mar Jly Mar Sept tion. Therefore, their concentration reflects dietary, metabolic processes and environmental effects. t has been also reported that the content of trace elements varies with indivisal hairs on a single hman head and with the length of the hair. As the hair samples, analyzed by netron activation analysis in this work, were taken from varios parts of the head and from the tip of the hair (length to 6 cm), we cold obtain only the average pattern of trace element concentration in the hair. The reslt for mercry is shown in Fig. 2. Table 2 contains the average concentration of 10 samples and its standard deviation. Mercry showed a characteristic variation dring their stay in Antarctica. Namely, mercry's average concentration and its standard deviation decreased from 6.3 ppm to 4.2 ppm and from 2.3 ppm to 0.6 ppm respectively at the end of the stay in Antarctica. And its concentration increased again and scattered over a wide range after the party members retrned to Japan. This trend in concentration and standard deviation of mercry appears to indicate the effect of speciality of the living conditions of the Antarctic Research Expedition party and the environment in Antarctica. KozKA (1972) and KozKA et al. (1972) have investigated the concentration of trace elements in 230 hair samples, which were collected from a variety of Japanese, representing different occpations and environments. The concentration of mercry in the hair ranged from 1 to 13 ppm, averaging 5.4 ppm for male, 4.6 ppm for female, and 5.0 ppm for total. HosmNo et al. ( 1966a, b) have reported the average of mercry to be 6.0 ppm. On the basis of these data, it seems reasonable to consider that the concentration of mercry in Japanese hair is 5,..,, 6 ppm. On the other hand, the vale of 1-2 ppm has been reported for foreigners and also for Japanese stdents staying in foreign contries. These facts sggest that the concentration of mercry in the hair reflects dietary and environmental effects. Thogh the environment in Ant-

6 Trace Elements in the Hairs of Wintering Members of JARE 69 C '.!:;E a.1.0 Q. C 0 \,, R ' \ \ \.!.. T Sep o G---- Fig. 3. Mar Sbject Jly Mar G----,....,... Sbject Variation of antimony content in hair dring the stay in Antarctica arctica seems to be little pollted, the concentration of mercry decreased to only 4.2 ppm which was considerably high compared wilh that of foreigners. Considering the fact that the food taken in Antarctica was prodced in Japan, the above-mentioned vale of mercry concentration may be ascribed to the intake of food. Fig. 3 shows the variation in concentration of antimony dring the stay in Antarctica. Two distinct peaks are noticed in Fig. 3. These peaks appeared in the hairs collected on board the icebreaker FJ or not very long after leaving the ship. This fact seems to indicate that some enviromental polltion occrred on the icebreaker FJ and the srface of the hair was contaminated with it, althogh the sorce of polltion is not clear at present. For other

7 70 Hiroshi KozKA and Ykio KANDA elements, no obvios reslt sggesting the effect of their living in Antarctica was obtained. The athors wish to thank Dr. T. MATSUDA who kindly arranged for this stdy, and the wintering members of the 13th Japanese Antarctic Research Expedition for spplying the hair samples. References FoRSHUFVUD, S., H. SMTH and A. WASSEN (1961): Arsenic content of Napoleon's hair probably taken immediately after his death. Natre, 192, FoRSHUFVUD, S., H. SMTH and A. WASSEN (1964): Napoleon's illness in the light of activation analysis of hairs from varios dates. Arch. Toxicol., 20, GRARD, F. and E. SABBON (1968): Selective removal of radio-sodim from netron-activated materials by retention on hydrated antimony pentoxide. J. Radioanal. Chem., 1, HOSHNO, 0., K. TANZAWA, Y. HASEGAWA and T. UKTA (1966a): Differences in mercry content in the hairs of normal individals depending on their home environment. J. Hyg. Chem., 12, HOSHNO, 0., K. TANZAWA, T. TERAO, T. UKTA and A. OcH (1966b): Qantitative determination of mercry in hair by activation analysis. J. Hyg. Chem., 12, KozKA, H. (1972): Factors having inflence on the trace elements contents in hair. J. Hyg. Chem., 18, KOZUKA, H., H. lsono, N. TSUNODA and T. NWASE (1972): Characteristics of trace elements in Japanese head hair. J. Hyg. Chem., 18, 1-6. (Received April 22, 1975)