The Heavy Metal Characteristics (Pb and Cu) in Wideng Crab Tissue from the Gonjol River, Demak

Objective and Background: The Gonjol river serves as a lifeline for the communities surrounding Demak's brackish water ponds. Currently, factory waste is poisoning rivers. The purpose of this research was to investigate the levels of heavy metals Pb and Cu in Wideng crab tissue, water, and sediment in the Gonjol river's upper course and estuary.

Methods: This study was place from January to March 2020. Heavy metal concentration was determined using atomic absorption spectroscopy. The linear regression method was used to analyze the data.

Results: Except for Cu in upstream and estuary sediments, the concentration of Pb and Cu in the waters, sediments, and Wideng crab tissue remained below the acceptable limits. Heavy metals Pb and Cu in both sediment and tissue did not reveal a significant association in the upstream and estuary, although there was a correlation between water and tissue. There is no association between silt and water in the upstream and estuary. The river's quality is based on the Decree of the Minister of the Environment of the Republic of Indonesia No.115 of 2003, which places it in category C, which means it has moderate levels of Pb and Cu pollution. While tissue and sediment levels are below the tolerance limit.

Conclusion: The state of the Gonjol River is a source of concern, particularly the circumstances of Cu and Pb, which allow bioaccumulation in the future, posing a threat to the ecosystem and the communities surrounding it.