Thailand's eastern provinces are essential as a hub for industry and tourism, effect to the study has purposed for heavy metal contamination of a beach in the Thai Gulf area in the east of Thailand was monitored and focuses on the use of the enrichment factor (EF) and geoaccumulation index (Igeo) to indicate the environmental condition of beaches. The 30 sample sites were in Chonburi (CHR), Rayong (RY), Chanthaburi (CB), and Trad (TR) provinces, along a sandy beach of about 320 kilometers in length. An inductively coupled plasma technique (ICP-OES) was used to analyze the heavy metals present in the samples. The sand of the range with granulometries greater than 0.85 (18%), between 0.85–0.25 (77%), or less than 0.25 mm (5%). The most common heavy metal found in the samples was Fe at 1632±931 mg/kg dry weight, and the number of heavy metals found in the samples did not exceed the Pollution Control Department of Thailand standards. Principle Component Analysis (PCA) indicated that land use activities influence Hg content. The Igeo of Hg was 1–1.99 (moderately polluted) in sample location 4th of the Rayong province, which has an industrial zone and a port. The EF was mainly within the range of 2–5 in the four provinces studied (indicating deficiency to minimal enrichment), except for one location in Trad and Rayong province, which had an EF of over 5; a possible reason for this is that the area is close to agricultural and aquacultural zones, the government organizations can use the data to plan, monitor, and promote tourism in the future.

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