Title

BIOACCUMULATION OF CADMIUM (Cd) IN PHILIPPINE OYSTERS Crassostrea iredalei AND Magallana bilineata SOLD IN THE STREETS OF TUDELA, MISAMIS OCCIDENTAL

Author(s)

INDOC, SHANNERY NICOLE R.

LAURETE, DAPHNE JAYCE D.

SEPE, DANNAH GRACE R.

ZAMBRA, JUDECAEL KALIL D.

Affiliation

Misamis University

Degree Program

Bachelor of Science in Medical Technology

Contributor

Guiaman, Shaira - Adviser
Enguito, Marie Rosellyn C. MSc Bio- Panel member
Parba, Meliza PhD - Panel member
Lao, Karl Maxel O. RMT,MSc. LMS- Chairman

Year

2026

Abstract

Heavy Metals can enter the environment through natural processes and human activities such as farming, manufacturing, and waste dumping; they can be toxic even in small amounts. This
research examines cadmium (Cd) levels in oysters sold on the streets of Tudela, Misamis Occidental. Oysters are popular in this area and are often eaten raw, raising health concerns about heavy metal contamination. While several studies have examined the bioaccumulation of heavy metals, such as cadmium (Cd), in oysters from different regions of the Philippines and abroad, there is no scientific research that specifically examines oysters marketed on the streets of Tudela for potential heavy metal contamination. Addressing this gap is necessary because increased oyster consumption in the area may pose health hazards if oysters are contaminated. The study used a quantitative, descriptive research approach; the researchers collected three oysters from two species (Crassostrea iredalei and Magallana bilineata) from two street vendors in Tudela. A certified laboratory analyzed the oysters to measure cadmium levels. The results showed that the overall mean for cadmium concentration in Crassostrea iredalei was 0.0664
mg/kg, and 0.0819 mg/kg for Magallana bilineata. The results are compared to food safety guidelines set by the Bureau of Fisheries and Aquatic Resources (BFAR) and Food and Agriculture Organization (FAO), and the values from the analyzed oyster samples were below the maximum allowable limit of 0.50 mg/kg, indicating that the oysters were safe for consumption. However, continuous and frequent consumption of oysters containing cadmium, even at low concentrations, may lead to bioaccumulation in the human body over time and potentially cause adverse effects. Therefore, regular monitoring of cadmium levels in oysters sold in the area is recommended to ensure consumer safety.

Keywords

Bioaccumulation, Cadmium, Oyster, Atomic Absorption Spectrophotometry