# Honey as a Bioindicator: Pollution's Effects on Its Quality in Mining vs. Protected Sites
## 4 Discussion
The results revealed elevated concentrations of heavy metals, with maximum values of 3.41 mg/kg for Pb, 3.81 mg/kg for Cd, 36.40 mg/kg for Zn, and 33.00 mg/kg for Cu. In areas impacted by mining, industrial activities, and intensive agriculture, heavy metal contamination poses a significant environmental hazard. Elevated concentrations of these metals can be toxic to honeybees, while their accumulation in bee-derived products presents potential risks to human health [18]. In their studies, [PERSON] and [PERSON] [68] highlighted that lead has emerged as a significant environmental contaminant, often occurring in elevated concentrations due to various anthropogenic activities, particularly mining operations. The microbiological analysis demonstrated that all the honey samples, regardless of the area from which they were sampled, had both antibacterial and antifungal activity against all the strains studied. These results are consistent with those of other studies conducted in our country [37,69] and in other parts of the world [70,71] on the antibacterial and antifungal effects of polyfloral honey. It is already known that the antimicrobial \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Country/Organization** & **Lead, mg/kg** & **Cadmium, mg/kg** & **Mercury, mg/kg** & **Methyl-mercury, mg/kg** & **Arsenic, mg/kg** & **Copper, mg/kg** & **Tin, mg/kg** \\ \hline UE (EFSA) & 0.10 & – & – & – & – & – & – \\ Codex Alimentarius & 0.10 & – & – & – & – & – & – \\ Poland (RMH) & 0.30 & 0.03 & 0.01 & - & 0.20 & - & - \\ India (FSSAI) & 2.50 & 1.50 & 1.00 & 0.25 & 1.10 & 30.00 & 250.00 \\ China (CFSA) & 0.05 & 1.00 & 0.01 & – & 0.05 & – & – \\ \hline \hline \end{tabular} Note: EFSA—European Food Safety Authority; RMH—Regulation of the Minister of Health from Poland; FESAI—Food Safety and Standards Authority of India; CFSA—China National Center for Food Safety Risk Assessment, part of SAMR—State Administration for Market Regulation.  
\end{table} 
Table 11: Maximum permissible limits for heavy metals in honey—international comparison. activity of honeys is different according to the source of the flower and origin area. For polyfloral honey, because the sources are varied and combined from several plant species, it is expected that the antimicrobial effect will be intense. There is data from the literature that highlights the use of honey as a natural indicator of pollution in mining areas, demonstrating its ability to detect contaminants, such as heavy metals and pesticides [15; 72; 73]. Due to different antimicrobial effects of honey from mining areas compared to protected ones, our results indicate honey as a possible indicator of polluted areas. The values presented for the honey samples from mining regions and protected areas can be statistically preprocessed using a principal component analysis (PCA). This method is suitable for reducing the dimensionality of the large dataset, containing variables such as bacteria, fungi, chemical compounds, and heavy metals. It helps identify the relationships between samples and determine whether the samples from mining areas are clearly distinguishable from those from protected areas. A PCA was applied to a dataset containing the microbiological parameters (presence of bacteria and fungi), bioactive compounds (phenols, flavonoids), and heavy metal content (Pb, Cd, Fe, Cu, and Zn) of the honey samples. The aim of this analysis was to identify the main directions of variation in the data and highlight any distinctions between honey from the mining areas (S) and that from the protected areas (SS). Figure 4 presents the results of the PCA applied to the honey samples to explore patterns and groupings based on their chemical composition and antimicrobial activity. The resulting PCA plot illustrates a clear separation between the two types of samples. The samples labeled \"S\" (S1-S4), corresponding to the mining areas, are distinctly grouped apart from the \"SS\" samples (SS1-SS4), originating from the protected areas.