Trace elements, including Fe, Zn, Cu, Mn, Cr, and Ni, which humans need in amounts of less than 50 mg/day, and major elements like K, Ca, and Mg, which are required at >50 mg/day, were determined, while Al, Ba, Bi, B, Cd, and Pb are ultra-trace elements that frequently exist in the dry matter of the routine diet at levels less than 50 ng/day and typically less than 1.0 µg/day [
59,
60]. Variability in the content of major elements such as potassium in foods is important because potassium plays a critical role in maintaining normal cellular function, nerve transmission, and muscle contraction, all of which are essential for overall health and physiological balance [
61]. Insufficient potassium intake is associated with increased risk of hypertension and cardiovascular diseases [
62]. Mineral analysis of honey samples H-1, H-2, and H-3, representing the concentrations of metals (both essential and toxic metals), is given in
Table 6 and
Table 7. Studies report that there are various means of mineral enrichment in honey, in particular, the minerals present in the soil that dissolve in water and are taken up by plant roots and shifted to plant nectar via an osmoregulatory process. Such soil-derived minerals and metals are transferred through honeybees while interacting with nectar [
63].
3.2.1. Essential Minerals
The most abundant essential mineral detected in honey samples was potassium (K), ranging from 922 to 1136 mg/kg (average level of 1018 mg/kg), followed by calcium (Ca), magnesium (Mg), iron (Fe), boron (B), and barium (Ba) as depicted in
Table 6. A comparison of the essential minerals from a pure honey source and the honey samples of three different regions reveals that almost all minerals are similar in concentrations except potassium (K) with lesser concentrations;
Figure 2. This variation may be due to the climatic conditions, the nature of the soil, and the low K in the water of the region.
In the present research, the potassium value is higher than the mean reference value of 135 mg/kg reported in Ethiopian honey by Gebeyehu et al. [
64] but lower than the mean value (2250.39 mg/kg) of honey from Poland reported by Tarapatskyy et al. [
65]. Calcium is the second most prevalent mineral, with a mean value of 124 mg/kg. The calcium content of honey in the present analysis is higher than the mean value of 85.2 mg/kg reported by Hungerford et al. in Australian honey [
24]. According to other studies, both of these essential minerals are the most significant nutrients in honey [
63,
64]. The maximum value of potassium was found in the honey sample H-1 and the minimum in H-2. Barium was noted to have a minimum level, less than 0.01 mg/kg, which was lower than the mean value of 0.3 ± 0.2 mg/kg reported earlier by Hungerford et al. [
24]. Subsequently, B, Fe, and Mg were found to be at 5.49 ± 2.88, 3.88 ± 2.33, and 68.77 ± 41.41 mg/kg, respectively. The mean content of boron (B) in the present study is slightly higher than that reported earlier (4.7 ± 2.2 mg/kg) by Hungerford et al. [
24], while the present mean level of iron in honey is quite close to that of an earlier study (3.80 mg/kg) reported by Akharaiyi et al. [
48], and the mean content of Mg is lower than that reported earlier (80.70–119.30 mg/kg) by Alqarni et al. [
66]. Magnesium contents were above the limit set by the Codex standard, i.e., 25 mg/kg, whereas iron concentrations were under the tolerable standard set by the Codex standard, i.e., 15 mg/kg [
14].
Figure 3 shows the comparative relationship between the individual sample’s essential minerals and the recommended daily intake value (RDI) for health taken from the literature. Green, red, and orange dots represent values within the recommended limit, below the limit, and above the limit, respectively. In terms of assessing nutritional value and health risks, the error bars provide a clear and insightful comparison by representing scientifically defined intake levels. Black lines indicate the RDI. In the present study, boron was found to be beyond the limit, barium within the limit, and potassium, calcium, iron, and magnesium were found to be below the recommended standard levels. These findings suggest that honey can serve as a source for the mineral shown by the green dot, i.e., barium. However, it cannot be considered as a significant dietary source for Ca, Fe, K, and Mg. In the case of B, monitoring is important due to its narrow safety margin.
The Pearson correlation (r) of essential metals in honey samples is shown in
Table 7. There was a highly significant positive correlation between Fe and B (r = 0.94397), so a significant positive correlation indicates that the amounts of boron and iron in honey are strongly correlated. Larger levels of boron are typically linked to larger levels of iron. A strong positive correlation between Ca and B and between Ca and Fe (r = 0.999836 and r = 0.949787) indicates that the Ca level depends on B and Fe. The correlation of Mg to B, Fe, and Ca, with respective r values (r = 0.980388, r = 0.990498, and r = 0.983794), indicates a strong relationship between magnesium and calcium, boron, and iron, indicating that these metals may have comparable origins or external factors. The positive correlation between K and B, Fe, Ca, and Mg (r = 0.985713, r = 0.986072, r = 0.988599, and r = 0.999576) suggests that these metals have a common route or a robust geochemical association. There is a moderate negative correlation between Fe and Ba (r = −0.48488), suggesting that distinct components in the honey matrix have different origins, levels of movement, or interactions.
3.2.2. Toxic Metals
The abundant toxic metal determined in honey samples was aluminum (Al), ranging from 4.13 ± 0.11 to 9.08 ± 0.32 mg/kg with an average content of 6.11 ± 2.62 mg/kg (
Table 8). A recent study shows a higher mean content of Al (1.2 mg/kg) than in Australian honey [
24]. The higher value of aluminum was noted in H-1 (9.08 ± 0.32 mg/kg) and the minimum in the H-2 (4.13 ± 0.11 mg/kg) honey sample.
Cadmium and nickel were determined with contents less than 0.01 mg/kg, which is below the quality reference standards. The safe limit for nickel (Ni) set by the FAO/WHO expert committee on food additives (ECFD) is 5.0 mg/kg [
14]. The standard limit for cadmium (Cd) is 0.05 mg/kg according to European legislation and the Codex [
21]. According to the Codex standard, the threshold limit for zinc (Zn) and copper (Cu) is below 5.0 mg/kg [
21]. In the present study these metal levels were found to be below the permissible limits.
In the present study, the Cu value was higher than the mean value of 0.05 ± 0.02 mg/kg reported earlier by Nemo et al. [
53]. Lead (Pb) was found with an overall average concentration of 0.18 ± 0.05 mg/kg, which was below the standard limit of 3.0 mg/kg suggested by FAO/WHO [
67]. The present study’s lead value is higher than the mean value of 0.028 ± 0.074 mg/kg reported by Hungerford et al. [
24]. However, Cd and Pb are considered bioindicators for contamination in honey [
68]. Pb is a toxic metal and has adverse and long-lasting effects on children and causes high blood pressure and kidney damage in adults [
69]. The present study’s mean Cd level is close to that reported in the study by Hungerford et al. [
24]. Among heavy metals, Pb is the most hazardous substance, which is commonly introduced into the environment through vehicular emissions, whereas Cd originates from industrial waste incinerators moving from soil to plant; both metals directly contaminate the nectar [
70]. The concentrations of Bi, Cr, Mn, and Sr were noted with overall values of 0.08 ± 0.04, 0.54 ± 0.02, 0.59 ± 0.12, and 1.14 ± 1.38 mg/kg, respectively. In the current analysis, Mn, Zn, and Ni levels are lower than the ranges 4.15–6.04, 3.44–5.72, and 0.15–0.67 mg/kg, respectively, reported in the literature by Alqarni et al. [
66]. The average values of Sr and Cr in the present study are higher than the mean values of 0.4 ± 0.3 and 0.008 mg/kg observed earlier by Hungerford et al. [
24]. The observed Mn and Cr levels are under the limit set by WHO, i.e., 5.5 µg/g and 100 µg/g, respectively [
28,
71]. Nevertheless, at high levels, these metals negatively impact the operation of several organs and cell functions [
72].
The results of the Pearson correlation (r) of toxic metals in honey samples are shown in
Table 9. According to the correlation, there was a perfect negative correlation (r = −1) between Ni and Cd. According to this association, it is questionable that these two metals will coexist in the same samples at high concentrations. This could be because of different environmental sources or competitive exclusions in soil or plants. Moreover, a highly significant positive correlation was found between Cr and Cd (r = 0.998337), Mn and Al (r = 0.959199), Ni and Mn (r = 0.908928), Pb and Ni (r = 0.980245), Sr and Al (r = 0.997496), Sr and Mn (r = 0.976791), and Zn and Cu (r = 0.990897). These significant positive correlations indicate that metals are closely related and share environmental, anthropogenic, geochemical, industrial, and agricultural sources. However, a high significant negative correlation occurred between Cu and Bi (r = −0.99329), Mn and Cd (r = −0.90893), Ni and Cr (r = −0.99834), Pb and Cd and Cr (r = −0.98025 and r = −0.99002), and Zn and Bi (r = −0.99982), which suggested that metals might have originated from different processes and sources due to competing bioaccumulation or environmental interactions.
The present analysis revealed a moderate positive correlation between Bi and Al (r = 0.713026), Ni and Al (r = 0.753956), and Sr to Ni (r = 0.798523), while indicating a moderate negative correlation between Cd and Al (r = −0.75396), Cr and Al (r = −0.71484), Cu and Al (r = −0.78934), Sr and Cd, Cr, and Cu (r = −0.79852, r = −0.7625, and r = −0.74395). The health hazards of toxic metals such as chromium (Cr), lead (Pb), and cadmium (Cd) have been widely accepted, necessitating their reliable estimation in food products such as honey. The main sources of hazardous metal contamination in foods mainly include the increasing magnitude of environmental pollution caused by rapid industrialization and automobile expansion, as well as diverse anthropogenic activities. The high positive connection between Cr and Cd suggests that these harmful metals are commonly found in the environment. Negative correlations may indicate regions with higher concentrations of one harmful metal than another, which could help guide mitigation measures.
In
Figure 4 every bar shows the presence of toxic metals in the individual honey samples selected for this research. The plot shows the relationship between the toxic metal concentration of all individual samples and their regulatory limits. The red dashed lines represent the safe limits of each metal. A possible health hazard could arise if the metal concentration rises above the acceptable threshold. If the bar crosses the dashed line, it exceeds the safe limit, and it may pose serious potential risk associated with the specified metal. Analysis revealed that all the honey samples are safe concerning the regulation limits of metals set by international standards.
Figure 5 is a heat map representing the exceedance status of metals in individual samples with respect to RfD values, whether they meet the safe limit or not. The green color blocks show the safe limits with zero concentration, whereas the red color blocks show the concentration above the safe limits. According to the heat map, the maximum concentration limit is 1, and concentrations of the metals exceeding 50% of the level are a risk for health, whereas those below are safer. Considering the two-way presentation of the heat map, it was observed that the sample from Faisalabad (F-1–F-5) exceeded the safe limit and has a risk with regard to Mn, Cu, Al, Zn, and Pb (the Pb level was safe in F-4), whereas the samples from Gujranwala (G-1–G-5) and Kashmir (K-1–K-5) exceeded the safe limit and have a risk with regard to Cu, Al, Zn, and Pb. However, the findings suggest that the level of Mn was safe in all Gujranwala and Kashmir samples. The findings suggest that all the samples from Gujranwala, Kashmir, and Faisalabad had high concentrations of zinc, but zinc is not as harmful as other heavy metals because it is necessary for human health. However, an optimized use of honey can be healthier for humans without health risks. It is also observed through the heat map that all the honey is safe in terms of Cd, Bi, Cr, Ni, and Sr metals.
A biplot of toxic metals for individual samples is represented in
Figure 6. Al, Cr, and Zn dominate PC1 (60–70% variance), suggesting that they are the main contributors to sample differentiation. Mn and Sr have an impact on PC2 (20–30% variance), indicating a secondary source of variation. Cu and Zn confirm their association by pointing in the same direction. The close clustering of samples F-1 through F-5 suggests that their metal profiles are comparable. Another group, K-1 to K-5 and G-1 to G-5, represents different metal compositions. PCA verifies that metals such as Al, Cr, and Zn are the main causes of variation, with Mn and Sr playing a secondary role (
Figure 6).