Tiantip Boonchuay. Morphology and histology of the family littorinidae and potamididae at TBT contaminated areas, Chonburi province . Master's Degree(Environmental Biology). Mahidol University. : Mahidol University, 2008.
Morphology and histology of the family littorinidae and potamididae at TBT contaminated areas, Chonburi province
Abstract:
The objectives of this research were to study the morphology and histology of the littorinid snails (Littoraria articulata and Littoraria strigata) and potamidid snails (Cerithidea cingulata and Cerithidea quadrata) and TBT accumulation on sediments and snail tissues collected from Tumbol Laemchabang, Samet and Chuksamet (Chonburi Province). Semithin sections with 0.7-1 μm thickness and methylene staining were used for histological study. Gas chromatography-mass spectrometer (GC-MS) were used to determine TBT accumulation on sediments and snail tissues. The highest and lowest TBT accumulation on sediments were 10.53 and 1.56 ng/g (wet wt), respectively whereas the highest and lowest TBT accumulation in snail tissues were 2.56 and 1.06 ng/g (wet wt), respectively. The shell size of snails with high TBT accumulation in their tissues were smaller than those with low TBT accumulation. For morphological study, the open pallial reproductive organ in both sexes and aphallic male presented in C.cingulata and C. quadrata were studied. However, there were no differences in the internal anatomy of the same species as they had various TBT accumulations in their tissues. For histological study, the lower in amount of stages III, IV and V oocytes was observed in the ovary of C. cingulate with 1.99 ng/g (wet wt) TBT accumulation in their tissues. Moreover, the digestive gland of L. articulate and L. strigata with 2.56 ng/g (wet wt) TBT accumulation in their tissues showed larger vacuoles. This research showed that TBT can accumulate in both organisms and the environment. TBT was species specific to organisms and even at low levels,1-2 ng/g, it can cause effects- reduce egg production and increase vacuolar size to organisms