Effects of environmental pollutant Benzo(a)pyrene on the internal defense system of terrestrial molluscs.

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 15510030
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Environmental impact assessment/Environmental policy
• Research Institution: Dokkyo University School of Medicine
• Principal Investigator: YAMAGUCHI Keiichiro Dokkyo University, School of Medicine, Lecturer, 医学部, 講師 (70049211)
• Co-Investigator(Kenkyū-buntansha): SORIMACHII Kenji Dokkyo University, Professor, 医学部, 教授 (30118476) ; TAKAHASHI Masanori Dokkyo University, Associate Professor, 医学部, 助教授 (70103356) ; SEO Naomi Tokyo Medical University, Assosiate Professor, 医学部, 助教授 (90074640) ; SASAKI Yuri Tokyo Medical University, Lecturer, 医学部, 講師 (60074720)
• Project Period (FY): 2003 – 2004
• Keywords: environmental pollutant / Benzo(a)pyrene / terrestrial molluscs / Limax marginatus / internal defense system / hermaphroditic gland / mid-gut gland / albumin gland

Research Abstract

Benzo(a)pyrene (BaP) is a ubiquitous environmental pollutant. Besides being a potent carcinogen, it has also been found to be highly immunotoxic in mammalian systems. However, there is little information whether the hazardous chemicals may affect the immune system in invertebrates. When the terrestrial slugs, Limax marginatus, were kept on the filter paper, which was soaked with acetone solution of BaP (500ppm) and dried up, their body weight often increased significantly during 5 weeks. This result showed that the exposure to BaP made accelerate the growth of albumin gland in the slug. The content of BaP being contained in the mid-gut gland, hermaphroditic gland (gonad) or albumin gland was analyzed by high performance liquid chromatography(HPLC) method. Each eluting sample was obtained from homogenizing the organ in methanol-benzene (3:1), treating with super sonic wave for 1 hr and then centrifuging at 3,000 rpm for 10 min. The sample was filtered with Millipore filter (0.45 μm) and applied on the column (VP-ODS, 4.5×150 mm). We had established the HPLC system that could detect BaP density less than 10^<-3>ppm. This density is not considered to be high in the organs of slug from where BaP pollution may be hardly expected. The average weight of the albumin glands of slugs collected on the street where was much traffic was significantly larger than that on the field where was little traffic (p=0.039). This fact suggests that the growth of albumin gland of the slug may be accelerated by BaP.