Assessment of chemical, heavy metal, and microbiological contamination of Indonesian seaweed-based food products

Indonesia ranks as the second-largest global producer of seaweed. To maximize the use of these resources, innovative seaweed-based food products are being developed. This study evaluates the prevalence of chemical and microbiological contamination in Indonesian seaweed-based food products. Microbiological parameters assessed included total viable count, coliforms, Escherichia coli, Staphylococcus aureus, Vibrio species, Salmonella species, and yeast and mold. Chemical contamination was evaluated by measuring aflatoxin B1 and conducting a comprehensive assessment of heavy metals. Results indicated that 20% of samples contained aflatoxin B1 at concentrations ranging from 0.14 to 2.12 µg/kg. Heavy metal analysis showed contamination with lead in 50% of samples, arsenic in 35%, cadmium in 25%, and mercury in 5%. Only 25% of heavy-metal-contaminated samples exceeded the Indonesian National Standard limits. Microbial counts ranged from fewer than 10 to 10⁵ CFU/g, coliforms from fewer than 3 to 830 MPN/g, and yeast and molds from fewer than 10 to 10² CFU/g. All samples had E. coli and S. aureus counts below 10 CFU/g and tested negative for Salmonella and Vibrio species. Most products were assessed as safe for consumption. The findings underscore the need for improved food-processing practices to enhance product quality, ensure higher safety standards, and increase overall market value.

Abdullah R, Kamarozaman NS, Abdullah SS, Aziz MY, Aziza HBA,2025. Health risks evaluation of mycotoxins in plant-based supplements marketed in Malaysia. Sci Rep 15:1244. DOI: https://doi.org/10.1038/s41598-025-85280-z

Alp D, Bulantekin Ö, 2021. The microbiological quality of various foods dried by applying different drying methods: a review. Eur Food Res Technol 247:1333-13343. DOI: https://doi.org/10.1007/s00217-021-03731-z

Barberi ON, Byron CJ, Burkholder KM, Gelais AT, Williams AK, 2019. Assessment of bacterial pathogens on edible macroalgae in coastal waters. J Appl Phycol 32:683-96. DOI: https://doi.org/10.1007/s10811-019-01993-5

Begum R, Akter R, Dang-Xuan S, Islam S, Siddiky NA, Uddin AA, Lindah JF, 2023. Heavy metal contamination in retailed food in Bangladesh: a dietary public health risk assessment. Front Sustain Food Syst 7:1085809. DOI: https://doi.org/10.3389/fsufs.2023.1085809

BPOM RI, 2009. Peraturan Kepala Badan Pengawas Obat dan Makanan Republik Indonesia Nomor HK.00.06.1.52.4011 Tentang Penetapan Batas Maksimum Cemaran Mikroba dan Kimia Dalam Makanan. Badan Pengawas Obat dan Makanan Republik Indonesia ed., Jakarta, Indonesia. [Regulation in Indonesian].

BPOM RI, 2018. Peraturan Badan Pengawas Obat dan Makanan Nomor 8 Tahun 2018 Tentang Batas Maksimum Cemaran Kimia dalam Pangan Olahan. Badan Pengawas Obat dan Makanan Republik Indonesia ed., Jakarta, Indonesia. [Regulation in Indonesian].

BPOM RI, 2019. Peraturan Badan Pengawas Obat dan Makanan Nomor 13 Tahun 2019 Tentang Batas Maksimal Cemaran Mikroba Dalam Pangan Olahan. Badan Pengawas Obat dan Makanan Republik Indonesia ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2000. Syarat Mutu Mi Instan (SNI 01-3551-2000). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2008. Syarat Mutu Kembang Gula-Bagian 2: Lunak (SNI 3547.2-2008). (regulation in Indonesian). Badan Standardisasi Nasional ed., Jakarta, Indonesia.

BSN, 2015a. Syarat Mutu Agar-agar Tepung (SNI 2802:2015). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2015b. Syarat Mutu dan Keamanan Rumput Laut Kering (SNI 2690:2015). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2015c. Syarat Mutu Makanan Ringan Ekstrudat (SNI 2886:2015). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2016a. Syarat Mutu Garam Konsumsi Beriodium (SNI 3556:2016). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2016b. Syarat Mutu Kerupuk Ikan, Udang, dan Moluska (SNI 8272:2016). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2017. Syarat Mutu Karaginan Murni (SNI 8391-1-2017). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

BSN, 2022. Syarat Mutu Biskuit (SNI 2973-2022). Badan Standardisasi Nasional ed., Jakarta, Indonesia. [Regulation in Indonesian].

Choudhury S, Medina-Lara A, Smith R, Daniel N, 2022. Research on health impacts of chemical contaminants in food. Bull World Health Organ 100:180-180A. DOI: https://doi.org/10.2471/BLT.21.287532

Cotas J, Tavares JO, Silva R, Pereira L, 2024. Seaweed as a safe nutraceutical food: how to increase human welfare? Nutraceuticals 4:323-62. DOI: https://doi.org/10.3390/nutraceuticals4030020

Farghl AAM, El-Sheekh MM, El-Shahir AA, 2023. Seaweed extracts as biological control of aflatoxins produced by Aspergillus parasiticus and Aspergillus flavus. Egypt J Biol Pest Control 33:50. DOI: https://doi.org/10.1186/s41938-023-00696-x

Food and Agriculture Organization, 2018. The state of world fisheries and agriculture: meeting the sustainable development goals. Rome, Italy.

Food and Drug Administration, 2019. Escherichia coli (E. coli). Available from: https://www.fda.gov/food/foodborne-pathogens/escherichia-coli-e-coli.

Ghosh S, Nurain N, Hasan MF, Raihan MM, Akter F, 2020. Identification of coliform in common street food and associated factors of contamination in Noakhali, Bangladesh: a cross-sectional study. Asian Food Sci J 18:12-22. DOI: https://doi.org/10.9734/afsj/2020/v18i130206

ISO, 2017a. Microbiology of the food chain, horizontal method for the detection, enumeration, and serotyping of Salmonella Part 1: detection of Salmonella spp. ISO Norm 6579-1:2017/Amd 1:2020. International Standardization for Organization ed., Geneva, Switzerland.

ISO, 2017b. Microbiology of the food chain, horizontal method for the determination of Vibrio spp. Part 1: detection of potentially enteropathogenic Vibrio parahaemolyticus, Vibrio cholerae, and Vibrio vulnificus. ISO Norm 21872-1:2017. International Standardization for Organization ed., Geneva, Switzerland.

ISO, 2021. Microbiology of the food chain, horizontal method for the enumeration of coagulase-positive staphylococci (Staphylococcus aureus and other species). Part 1: method using Baird-Parker agar medium. ISO Norm 6888-1:2021/Amd 1:2023. International Standardization for Organization ed., Geneva, Switzerland.

Ibrahim S, Majumder A, Haq R, Logesh K, EswarI, Hariprakash M, Kumar SD. 2025. Seaweed minerals: unlocking functional food potential from an Indian perspective. Discover Oceans 2:38. DOI: https://doi.org/10.1007/s44289-025-00077-2

Ivanov V, Shevchenko O, Marynin A, Stabnikov V, Gubenia O, Stabnikova O, Schevchenko A, Gavva O, Saliuk A, 2021. Trends and expected benefits of the breaking edge food technologies in 2021–2030. Ukrainian Food J 10:7. DOI: https://doi.org/10.24263/2304-974X-2021-10-1-3

Jairoun AA, Shahwan M, Zyoud SH, 2020. Heavy metal contamination of dietary supplements products available in the UAE markets and the associated risk. Sci Rep 10:18824. DOI: https://doi.org/10.1038/s41598-020-76000-w

Jakubczyk K, Melkis K, Dalewski B, Janda-Milczarek K, 2024. Assessment of antioxidant properties and mycotoxin profile of commercial spirulina supplements. Food Biosci 62:105461. DOI: https://doi.org/10.1016/j.fbio.2024.105461

Julyasih K, Purnawati A, 2019. Potensi Rumput Laut Dalam Menghambat Pertumbuhan Jamur Aspergillus flavus. (article in Indonesian). Agrotrop J Agric Sci 9:82-6. [Article in Indonesian]. DOI: https://doi.org/10.24843/AJoAS.2019.v09.i01.p08

Khandaker MU, Chijioke NO, Heffny NAB, Bradley DA, Alsubaie A, Sulieman A, Faruque MRI, Sayyed MI, Al-mugren KS, 2021. Elevated concentrations of metal(loids) in seaweed and the concomitant exposure to humans. Foods 10:381. DOI: https://doi.org/10.3390/foods10020381

KKP, 2023. Profil pasar rumput laut Indonesia. Jakarta. [Material in Indonesian]. Available from: https://kkp.go.id/storage/Materi/profil-pasar-rumput-laut66753a465fe09/materi-66753a4696928.pdf.

Li Y, Sun M, Mao X, You Y, Gao Y, Yang J, Wu, Y, 2018. Mycotoxins contaminant in kelp: a neglected dietary exposure pathway. Toxins 10:481. DOI: https://doi.org/10.3390/toxins10110481

Lipi JA, Runu UH, Majumdar PR, Hasan MMI, Hossain, MB, 2023. Microbiological evaluation of ready to eat product of Horina (Metapenaeus Monoceros) shrimp at a sea food industry of Bangladesh. Int J Fish Aqua Stud 11:40-3. DOI: https://doi.org/10.22271/fish.2023.v11.i3a.2807

Løvdal T, Lunestad BT, Myrmel M, Rosnes JT, Skipnes D, 2021. Microbiological food safety of seaweeds. Foods 10:2719. DOI: https://doi.org/10.3390/foods10112719

Lytou AE, Schoina E, Liu Y, Michalek K, Stanley MS, Panagou EZ, Nychas GJE, 2021. Quality and safety assessment of edible seaweeds Alaria esculenta and Saccharina latissima cultivated in Scotland. Foods 10:2210. DOI: https://doi.org/10.3390/foods10092210

Mendonca A, Thomas-Popo E, Gordon A, 2020. Chapter 5 - Microbiological considerations in food safety and quality systems implementation. In: Food safety and quality systems in developing countries. Academic Press, London, UK; pp 185-260. DOI: https://doi.org/10.1016/B978-0-12-814272-1.00005-X

Morgan J, 1999. Effects of processing on heavy metal content of foods. Adv Exp Med Biol 459:195-211. DOI: https://doi.org/10.1007/978-1-4615-4853-9_13

Naratama MR, Santoso I, 2020. Non-fecal and fecal coliform tests of ready-to-eat food and drinks using fluorogenic and chromogenic media. J Phys Conf Ser 1442:012064. DOI: https://doi.org/10.1088/1742-6596/1442/1/012064

Nazareth TM, Soriano Pérez E, Luz C, Meca G, Quiles JM, 2024. Comprehensive review of aflatoxin and ochratoxin a dynamics: emergence, toxicological impact, and advanced control strategies. Foods 13:1920. DOI: https://doi.org/10.3390/foods13121920

Ni’mah YL, Suprapto S, Ilmi MM, Agustin NI, Ameswari VD, 2017. Determination of shelf life with accelerated shelf life testing (ASLT) in beverage seaweed. IPTEK J Proc Series 4:156. DOI: https://doi.org/10.12962/j23546026.y2018i1.3533

Notowidjojo L, Ascobat P, Bardosono S, Tjahjana J, 2021. The potential of seaweed salt as an alternative low natrium salt: safety and sensory test. World Nutrition J 5:47. DOI: https://doi.org/10.25220/WNJ.V05.i1.0007

Peñalver R, Lorenzo JM, Ros G, Amarowicz R, Pateiro M, Nieto G, 2020. Seaweeds as a functional ingredient for a healthy diet. Mar Drugs 18:301. DOI: https://doi.org/10.3390/md18060301

Putri NP, Sanjaya AS, Sari NK, Sari RP, Bindar Y, 2018. Carrageenan Extracted from Eucheuma cottonii Through Variant of Drying Time. MATEC Web of Conf 156:02014. DOI: https://doi.org/10.1051/matecconf/201815602014

Prashant N, Sangwan M, Singh P, Das P, Srivastava U, Bast F, 2025. Anti-nutritional factors and heavy metals in edible seaweeds: challenges, health implications, and strategies for safer consumption. J Food Compos Anal 140:107283. DOI: https://doi.org/10.1016/j.jfca.2025.107283

Rushing BR, Selim MI, 2019. Aflatoxin B1: a review on metabolism, toxicity, occurrence in food, occupational exposure, and detoxification methods. Food Chem Toxicol 124:81-100. DOI: https://doi.org/10.1016/j.fct.2018.11.047

Setiowati AD, Isharyadi F, Sinurat E, Damayanti NTE, Susanto DA, Kristiningrum E, Suroto DA, Setyaningsih W, 2024. Improving the quality of dried seaweed (Gracilaria sp.) through the implementation of good aquaculture practices (GAP) in Brebes, central Java. Int J Des Nat Ecodyn 19:1019. DOI: https://doi.org/10.18280/ijdne.190331

Setiowati AD, Susanto DA, Kristiningrum E, Isharyadi F, Sinurat E, Suroto DA, Setyaningsih, W, 2026 Quality parameters of dried seaweed: challenges and future directions. CABI Reviews 21. DOI: https://doi.org/10.1079/cabireviews.2026.0017

Sinurat E, Fransiska D, Utomo BSB, Subaryono S, Nurhayati N, 2023. Characteristics of powder agar extracted from different seaweeds species and locations. Available from: https://doi.org/10.21203/rs.3.rs-2627637/v1. DOI: https://doi.org/10.21203/rs.3.rs-2627637/v1

Soethoudt JM, Axmann H, Kok MG, 2022. Indonesian seaweed supply chain : analysis and opportunities. Wageningen Food & Biobased Research, Wageningen, Netherlands. DOI: https://doi.org/10.18174/572002

Stévant P, Rebours C, 2021. Landing facilities for processing of cultivated seaweed biomass: a Norwegian perspective with strategic considerations for the European seaweed industry. J Appl Phycol 33:3199-214. DOI: https://doi.org/10.1007/s10811-021-02525-w

Subuntith N, Pornpimon S, Nanticha R, Traimat B, Verapong V, 2021. Biosafety, bacteriological quality and strategy of biopreservative administration for controlling spoilage bacteria in Thai traditional dried seafood products. Afr J Microbiol Res 15:512-21. DOI: https://doi.org/10.5897/AJMR2021.9503

Semple RL, Frio AS, Hicks PA, Lozare, JV, 1989. Mycotoxin prevention and control in foodgrains. Available from: https://www.fao.org/4/x5036e/x5036E00.htm#Contents.

Tropea A, 2022. Microbial contamination and public health: an overview. Int J Environ Res Public Health 19:7441. DOI: https://doi.org/10.3390/ijerph19127441

van der Heijden PGM, Lansbergen R, Axmann H, Soethoudt H, Tacken G, van den Puttelaar J, Rukminasari N, 2022. Seaweed in Indonesia: farming, utilization and research. (Report/Wageningen Centre for Development Innovation; No. WCDI-22-220). Wageningen Centre for Development Innovation. Available from: https://doi.org/10.18174/578007. DOI: https://doi.org/10.18174/578007

Wei W, Zhang F, Fu F, Sang S, Qiao Z, 2023. Rapid detection of total viable count in intact beef dishes based on NIR hyperspectral hybrid model. Sensors 23:9584. DOI: https://doi.org/10.3390/s23239584

World Health Organization, 2024. Food safety. Available from: https://www.who.int/news-room/fact-sheets/detail/food-safety.

Wirenfeldt CB, 2023. Processing of Seaweed and the Effects on Food Quality and Safety. Technical University of Denmark. Available from: https://backend.orbit.dtu.dk/ws/files/338777927/Thesis-FINAL-250423.pdf.

Zhang J, Ding T, Ahn J, Zhang Z, Liao X, 2025. Tracing microbial hazards in the aquatic supply chain: challenges, technologies, and future directions. Front Nutr 12:1673037. DOI: https://doi.org/10.3389/fnut.2025.1673037