| Project/Area Number |
14360116
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
General fisheries
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| Research Institution | National Institute for Environmental Studies |
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Principal Investigator |
HORIGUCHI Toshihiro National Institute for Environmental Studies, Environ.Chemistry Division, Senior Researcher, 化学環境研究領域, 主任研究員 (30260186)
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| Co-Investigator(Kenkyū-buntansha) |
YAMAKAWA Hiroshi Tokyo Univ.Marine Sci.and Technology, Fac.of Marine Sciences, Associate Professor, 海洋科学部, 助教授 (80017061)
SHIRAISHI Hiroaki National Institute for Environmental Studies, Research Center for Environ., Leader, 化学物質環境リスク研究センター, 室長 (10124348)
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| Project Period (FY) |
2002 – 2003
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| Project Status |
Completed (Fiscal Year 2003)
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| Budget Amount *help |
¥16,700,000 (Direct Cost: ¥16,700,000)
Fiscal Year 2003: ¥5,800,000 (Direct Cost: ¥5,800,000)
Fiscal Year 2002: ¥10,900,000 (Direct Cost: ¥10,900,000)
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| Keywords | Abalone / Endocrine Disruption / Ovo-testis / Tributyltin (TBT) / Triphenyltin (TPT) / Reproduction / Veliger Larvae / Juveniles / アワビ資源 / 繁殖 |
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| Research Abstract |
A country-wide survey on endocrine disruption in abalone was done, using abalone specimens from 32 sites of Japan. Ovo-testis and related gonadal abnormalities were histopathologically examined. Tissue concentrations of butyltin and phenyltin compounds were also analyzed and measured by GC-FPD. Percentages occurrence of ovo-testis in females were in the range of 0-19%. Low concentrations of butyltins and phenyltins were detected in tissues of abalone specimens. Organotin concentrations detected in the head were generally higher than those in muscle. Organotin concentrations in tissue seemed to be positively correlated with percentages occurrence of ovo-testis in females.
Three-month flow-through exposure experiments of tributyltin (TBT) (nominal concentrations of 50 and 500 ng/L as well as a control) resulted in spermatogenesis in ovary of females. A concentration-dependent manner was unclear between TBT concentration in seawater and percentage occurrence or the degree of ovo-testis in females.
The number of eggs spawned by adult abalone, fertilization rates, hatching rates, normally developing rates, survival rates and successfully settling-down rates of larvae, survival rates and growth rates of juveniles were evaluated in an organotin-contaminated site of Japan.
EC_<50> values of TBT and triphenyltin (TPT) to fertilized eggs and larvae of three species of abalone were also experimentally calculated. TBT concentrations detected in Japanese inshore waters were locally higher than the EC_<50> values.
Scuba diving was also done to evaluate the current status of recruitment of juvenile abalone in an organotin-contaminated site of Japan, and the relation between the number of adults and juveniles settled down there was analyzed.
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