Lead contamination in green mussel collected from selected coastal towns of Cavite / by Sheryl B. Borja.

Thesis (BS Biology) Cavite State University.

Includes bibliographical references.

College of Arts and Science (CAS)

SHERYL B. BORJA and GENALYN M. ROMEN. Lead Contamination in Green Mussels (Perna viridis) Collected from Selected Coastal Towns of Cavite. Undergraduate Thesis- Bachelor of Science in Biology. Cavite State University, April 2007. Adviser: Mrs. Rosemarie R. Calma.
This study was done to detect the presence of lead within the coastal municipalities of Cavite where green mussels were grown. Histopathological examination of the liver and gonads of Perna viridis was also done to describe the effects of lead on these tissues. A relationship was drawn between the body parameters and the gonadosomatic index or heptosomatic index, and between physicochemical parameters and lead level to verify the damage brought about by the presence of lead as primary pollutant in the selected sampling sites. A completely randomized design (CRD) scheme with lead level and frequency of sampling were utilized and green mussels samples were randomly collected from these experimental areas of Cavite namely; Bacoor, Kawit and Cavite City three times at four week interval. A total of 135 green mussels samples and two liters of water from each experimental site were collected for analyses. The data were statistically analyzed using one way ANOVA while Person correlation was used to determine the relationship between liver weight, body weight, HSI, Gonad weight and GSI. Results showed that Cavite City had the highest mean for body length and body width while Bacoor had the highest mean for liver and gonad weight. Some physicochemical properties of water quality were measured and analyzed; lead content, hardness, dissolved oxygen and turbidity. Kawit had the highest mean for dissolved oxygen and lowest mean for lead level, compared with Bacoor having the highest mean for lead level and hardness. Cavite City on the other hand, ranked 2nd among the three sites for mean for lead level and hardness. In general, all the water parameters tested were significantly different between the three sites. The organosomatic indices were analyzed and results showed that the HSI was highly correlated with mean liver weights and was not influenced by a change in its body weight. This would indicate that liver weight was a good bio indicator. GSI was useful in determining the reproductive maturity of the green mussel and not its body weight. Hispathologicalanalyses of the lever and gonads revealed necrotic lobules and degenerated hepatocytes. Irregularity in shapes and distribution of oocytes within the ovary and spermatogonia in the testes of hermaphroditic samples were also observed. Bacoor and Cavite City coastal areas were highly polluted and contaminated with harmful lead metal. Although Kawit recorded a lower lead level but this should cause an alarm. Overall results confirmed the possibility of lead poisoning due to bioaccumulation on green mussel consumers. Due to paucity of information regarding histopathological signs of lead-contaminated green mussels and unavailability of trace lead examination in the tissues, the histopathological evidences presented led us only to speculate that this might be due to the presence of lead which was ten times that of the Environmental Management Bureau (EMB, 2002) standard for class SA water or other environmental stressors.

Submitted to the University Library 05-10-2007 T-3548