Tetsuro Hongo

High Hair and Urinary Mercury Levels of Fish Eaters in the Nonpolluted Environment of Papua New Guinea

Hair and mercury concentrations of 134 fish-eating subjects in the Lake Murray area and 13 non-fish-eating subjects in the upper-Strickland area, Papua New Guinea, were studied. Hair mercury levels among the subjects in the Lake Murray area (mean = 21.9 micrograms/g, range = 3.7-71.9 micrograms/g) and urinary mercury levels (mean = 7.6 micrograms/g creatinine, range = 1.4-25.6 micrograms/g creatinine) were markedly higher than levels found in subjects from the upper-Strickland area (mean hair mercury = 0.75 micrograms/g, mean urinary mercury = 0.48 micrograms/g creatinine). Mercury intake of the fish eaters, estimated from mercury concentrations found in fish and from the observed amounts of fish consumed, was approximately 73 micrograms/d. Hair and urinary mercury concentrations were correlated significantly (r = .59), indicating that urinary mercury excretion was elevated because fish consumption was very high.

Elemental composition of ancient Japanese bones

Excavated bones (rib) obtained from 50 sites in Japan were measured by ICP atomic emission spectrometry and atomic absorption spectrometry for concentration of 19 elements, including Al, B, Ca, Cd, Cr, Co, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V and Zn. One hundred and forty-one specimens were classified into five groups according to Japanese prehistoric and historic eras (Jomon, Yayoi, Kofun, Kamakura and Muromachi, and Edo). The elements, with concentrations which showed no significant change with era were Al, B and Cr. Average concentrations of Ca were in the range 2-2.5 X 10(-1) g g-1 and those of P ranged from 1.1 to 1.3 X 10(-1) g g-1, indicating a well-preserved bone mineral matrix. The Ca/P ratio (mol/mol) was lowest in the Edo group--1.48 as compared with 1.54-1.66 in the other groups. Among the elements which showed changes with era were Pb, Fe, Co and Mn, all of which showed remarkably elevated concentrations in the Edo group. In addition to this unique elemental composition of Edo bones, samples from the Kofun era showed a completely different composition from those of other periods, i.e. they had the highest concentrations of Cd, Zn and Mg, and the lowest concentrations of Cu, K, Ni and Sr. The cause of the elevated Pb concentration in Edo bones is discussed in relation to human activities which may have led to environmental Pb pollution.

The Hair-Organ Relationship in Mercury Concentration in Contemporary Japanese

The hair-organ relationship of mercury concentration was investigated in 46 autopsy samples in Tokyo, Japan. Hair mercury levels were highly significantly correlated with organ Hg levels in the cerebrum, cerebellum, heart, spleen, liver, kidney cortex, and kidney medulla, when the total mercury or methyl mercury value in the organ was compared with the hair total mercury or organic mercury, respectively. When the inorganic mercury value was tested, significant correlations remained, with weaker coefficients in all the organs but the spleen. Stepwise multiple regression analysis evidenced that the hair organic mercury value was the major explanatory variable for the organ total mercury or organ methyl mercury value in all the organs. To explain the organ inorganic mercury value, the hair organic mercury value was the major variable for the cerebrum and kidney (both cortex and medulla), the hair inorganic mercury value was the major variable for the cerebellum and heart, and the hair phosphorous and hair organic mercury were the major variables for the liver; no explanatory variable existed for the spleen. Auxiliary explanatory variables accounted for the organ total mercury and inorganic mercury levels, among which the hair selenium value was conspicuous with negative regression coefficients.

Mercury concentration correlates with the nitrogen stable isotope ratio in the animal food of papuans

The relationships among element concentrations (Na, Mg, Al, P, K, Ca, Cr, Fe, Mn, Cu, Zn, Sr, total Hg, organic Hg, inorganic Hg, Pb) and stable carbon and nitrogen isotope ratios (13C/12C and 15N/14N) in animals consumed by the people called Gidra, who inhabit the lowland of Papua New Guinea, were examined. Animals analyzed included mammal, bird, fish, shellfish, reptile, crustacean, and insect. Highly significantly positive correlations were observed between total Hg concentrations and 15N/14N (r = 0.796), between organic Hg concentrations and 15N/14N (r = 0.781), and between inorganic Hg concentrations and 15N/14N (r = 0.739). This was interpreted to indicate that Hg was an element which accumulates in animals along the food chain. Based on the regression function of Hg on delta 15N, the bioconcentration factor for total, organic, and inorganic Hg was estimated to be 5.

Diversity and change of food consumption and nutrient intake among the Gidra in Lowland Papua

Food consumption and nutrient intake of the Gidra in lowland Papua, who number 1,850 and inhabit 13 villages, were analyzed by compilation of five two‐week (or twelve‐day) records, in a single village in 1971 and in four different villages (including the above village) in 1981. The nutrient intake of the Gidra varied both over time and among the villages. Difference in food consumption patterns included different proportions of plant staples such as sago flour, garden crops and purchased cereals. The animal protein sources, mainly game and fish, also markedly varied among the villages. These differences in food consumption were related to environmental conditions such as the fauna and flora in the environment of each village and to the degree of modernization as reflected in ability to purchase foods not locally grown. The causal relationship between ecological (environmental and cultural) conditions and food and nutrition is discussed, and a schematic model for this relationship is presented.

An Acute Mercuric Mercury Poisoning: Chemical Speciation of Hair Mercury Shows a Peak of Inorganic Mercury Value

A woman ingested a dose of sublimate (approximately 0.9 g) in an attempted suicide. She survived and recovered in response to a combination of therapies including chelate (BAL) therapy, plasma exchange, haemodialysis and peritoneal dialysis. Serum inorganic mercury concentration, urinary inorganic mercury excretion and hair inorganic and organic mercury and selenium concentrations, along the length from the scalp to the distal part, were measured. Longitudinal analysis of hair, revealed a peak in inorganic mercury corresponding to the time of mercury ingestion. Organic mercury and selenium in the hair had different patterns of longitudinal variation from that of inorganic mercury. The biological half-life (23.5 d) of serum inorganic mercury levels was in good agreement with values previously reported in the literature.

Urinary mercury level in Japanese school children: influence of dental amalgam fillings and fish eating habits

The influence of dental amalgam fillings and fish eating frequency on the urinary mercury (Hg) level was evaluated in 1642 children (ages: 3-18) living in Tokyo. Geometric mean of the urinary Hg level was 1.9 microgram Hg/l and 1.9 micrograms Hg/g creatinine (Cr) for boys and 2.1 micrograms Hg/l and 2.0 micrograms Hg/g Cr for girls. Multiple regression analysis was conducted using: (1) urinary Cr concentration (only in the case of urinary Hg expressed as microgram Hg/l); (2) age; (3) gender; (4) number of dental amalgam fillings; and (5) fish eating frequency as independent variables. As a result, all the variables examined were significant and the explanatory powers (square of multiple correlation coefficient) of these variables were 17 or 7% for urinary Hg expressed as microgram Hg/l or microgram Hg/g Cr, respectively. Number of dental amalgam fillings or fish eating frequency explained only up to 1.5% of the total variance of urinary Hg. Contribution of Cr concentration, age and gender to urinary Hg level is also discussed.

The relation of dietary selenium to erythrocyte and plasma selenium concentrations in Japanese college women

Abstract It was examined whether dietary selenium (Se) was correlated with Se levels in erythrocyte and in plasma and with erythrocyte glutathione peroxidase (GSH-Px, EC 1.11.1.9.) activities in a group of 25 female college students for a 5-day period. The mean daily dietary Se intake was 97.1± 22.2 ug. Major dietary sources of Se were wheat and wheat products (30%), fish and shellfish (20%), eggs (16%), and meast (14%). Erythrocyte Se concentrations (mean±SD: 0.31 ±0.04 ug/g) were significantly correlated with the Se intakes over 5 days from animal foods (r=0.45, p

Carbon and nitrogen isotopic characterization for Papua New Guinea foods

Stable carbon and nitrogen isotope ratios of the animal and plant food of the Gidra, who inhabit lowland Papua New Guinea and subsist mainly on hunting, gathering and horticulture, were measured to characterize the nutritional input of carbon and nitrogen of the Gidra. All the staple plant foods of the Gidra, such as sago and tuberous crops, were classified as C3 plants from their 13C/12C ratios (δ13C). The δ13C of the terrestrial mammals varied to a considerable extent (—11 to —26.5 per mil); the highest value was observed for a species of wallaby inhabiting savanna grassland while two other species of wallabies inhabiting woodland were —25.3 and —22.8 per mil. The δ13C of the aquatic animals was distinctive between marine (—17.0 to —7.1 per mil) and freshwater (—34.6 to —24.0 per mil) groups. The δ15N of the fishes and reptiles were generally higher than terrestrial animals. Major foods of the Gidra were isotopically divided into 5 groups: C3 plant, C3 plant feeder, C4 plant feeder, marine animal and fr...

Element intake of the Gidra in lowland Papua: Inter‐village variation and the comparison with contemporary levels in developed countries

Intake of 17 elements (Na, Mg, Al, P, K, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn Sr, Cd, Hg and Pb) was estimated in four villages of the Gidra in lowland Papua New Guinea. Among these elements, inter‐village variation of intake was relatively large for Na, Al, V, Fe, Ni, Cd, Hg and Pb. The variation was attributed to the different concentrations in foods and drinking water, and the differences in food consumption by different villages. Compared to the intake levels reported in Japan, the USA and European countries, Na, Ca, Ni, Cd and Pb intake in the Gidra was low. Low Na intake was principally caused by low consumption of salt. Low Na and Ca intakes were attributed to the low levels of consumption of animal foods. On the other hand, Mg, Al, K, Mn, Fe and Sr intake levels in the Gidra were high. In particular, extremely high Fe intake was attributed to region‐specific foods such as sago, wild seeds and shellfish.