Digestate: A Valuable Resource or a Potential Risk?
In recent years, digestate, a by-product of anaerobic digestion, has been increasingly used in agriculture—most commonly as an organic fertilizer. It is a material rich in nutrients such as nitrogen, phosphorus, and potassium, and it has the potential to replace part of conventional fertilizers. However, while digestate holds value, it also carries responsibility.
Digestate can contain impurities, pathogenic microorganisms, and even heavy metals, depending on the type and origin of the biodegradable feedstock used in the digestion process. If applied without prior control, its use may lead to contamination of soil, groundwater, surface water, and even food. This is why both Croatian and European Union regulations clearly stipulate that digestate must be tested and classified before being used for agricultural or other purposes.
In addition to being a legal requirement, regular analysis of digestate is also valuable from a technological perspective—it helps biogas plant operators monitor the efficiency of the process, identify any irregularities, and improve operational stability. At the same time, it allows farmers to apply nutrients more precisely and act responsibly toward the environment.
We are proud to inform you that our laboratory, Sample Control, has recently accredited a method for digestate analysis in accordance with the international standard HRN EN ISO/IEC 17025. This means we are now able to offer fully compliant, reliable, and expert digestate testing, including the determination of key physicochemical parameters (such as dry matter, pH, conductivity, nitrogen, phosphorus, and potassium), as well as the analysis of heavy metals and other potentially harmful substances.
In addition to laboratory analysis, Sample Control also offers on-site digestate sampling, ensuring that the entire process—from sample collection to delivery of results—is fast, simple, and fully compliant with regulations.
Microplastics in cosmetic products
Synthetic polymers, thanks to their many useful properties, have found applications in nearly all areas of human activity. Over time, plastic products end up in the environment, where various physical and chemical processes degrade them into smaller particles. This results in solid, water-insoluble plastic particles — macroplastics (>5 mm), large microplastics (1–5 mm), and microplastics (1 µm – 1 mm), according to international standards.
Presence and contamination of meat with perfluoroalkyl (PFAS) compounds
Perfluoroethyl compounds (PFAS) is a collective term for a very large group of fluorinated compounds, including oligomers and polymers, consisting of neutral and anion surface active compounds with high heat, chemical and biological inertness. Perfluorinated compounds are generally hydrophobic but also lipophobic and therefore will not accumulate in fat tissues as is usually the case with other persistent halogenated compounds. An important subgroup are (per) fluorinated organic surfactants, including perfluorooctane sulfonate (PFOS) and perfluorooctane acid (PFOA). For PFOS and PFOA, the European Food Safety Authority (EFSA) established a tolerable daily intake (TDI) for humans of 150 ng/kg body weight and 1.5 μg/kg body weight per day (EFSA 2008).