Assessment of Heavy Metal Concentrations in Seawater in the Coastal Areas around Daerah Istimewa Yogyakarta Province, Indonesia

Abstract

Due to anthropogenic influences that can cause heavy metal pollution in the aquatic environment, it is essential to know the amounts of heavy metals in coastal seawater to assess the potential damage of the ecosystem. The purpose of this study is to assess heavy metal concentrations (Cd, Pb, Cu, and Zn) in seawater in the coastal areas around Daerah Istimewa Yogyakarta Province, Indonesia. This study will be useful for the assessment and monitoring of marine pollution around the study area. A total of 9 water samples were collected in the close of nine types of coastal land use, namely mangrove ecosystem, tourist attraction, airport, harbor, mining area, bare land, shrimp pond, agricultural land, and settlement around Daerah Istimewa Yogyakarta Province in June 2021. The concentrations of Cd, Cu, and Zn were not detected, concentrations were below the limit of detection. The Pb concentrations at all sampling locations did not comply with seawater quality standards for ports, marine tourism, or marine biota based on the Ministry of Environment Decree No. 51, the year 2004 regulation. The source of Pb in the study area was estimated from anthropogenic and natural sources. The anthropogenic sources were corrosion of junk metal items, automobile traffic, resuspension of lead-contaminated soil dust, boat navigation, painting of boats, a coking coal transport service, fishing port, the supply of fuel, fertilizer, fuel for mining equipment, and transportation of mining activities. While the natural sources were the concentration of Pb contained in iron sand (a part of Quarterly Alluvium) eroded due to waves and wind then mixed in seawater.