Safety and Toxicological Risk Assessment of Northern Algerian Honeys

Abstract

The chemical composition of honey greatly varies due to diverse factors. Among these, the floral and geographical origin affects not only its quality (i.e., nutritional compounds, including minerals) but also its safety (i.e., contaminants, including potentially toxic elements). Industrialized countries can assure high-quality and safe honey through stringent regulations (e.g., Codex Standard 12-1981 and EU Regulation 915/2023) and testing. However, developing countries still suffer from regulatory gaps and less advanced monitoring systems. The present study aims to (1) monitor inorganic elements in an array of Algerian honeys, (2) explore the variability of the element profile in relation to their botanical and geographical provenance, and (3) assess the potential toxicological risk to African and European humans from consuming them. The element profile of honey is affected by both its geographical origin and its floral source. Many honeys exceeded the maximum levels set by the Codex Alimentarius for Mg (97% of samples), Fe (42% of samples), Zn (36% of samples), Cu (17% of samples), and Cd (50% of samples) and by the EU Regulation for Pb (64% of the samples). However, due to the small daily consumption of honey, exposure levels to the regulated elements were below the reference values. Similarly, negligible non-carcinogenic health effects were highlighted for all honeys. Hopefully, this study will encourage the Algerian government to effectively support the beekeeping sector by strengthening monitoring programs and establishing an adequate regulatory framework for honey.

1. Introduction

Beekeeping is an ancestral practice that is widespread all over the world, with significant differences from area to area based on the climate, the variety of flora and bees, and the degree of socio-economic development. Beekeeping becomes a necessity when it comes to maintaining biodiversity and developing sustainable agro-systems. Also, its various productions (i.e., honey, royal jelly, pollen, and venom) are a source of health and well-being to humans. Last but not least, beekeeping represents a promising option for income diversification in rural areas and ecologically difficult zones (e.g., mountains, forests, steppes, deserts, etc.) while contributing to poverty alleviation.

Honey production is undoubtedly a valuable commodity in beekeeping. Honey is the sugary substance produced by the Apis mellifera L. from the nectar of flowers (nectar honey), or from plant secretions or substances secreted by sucking insects on plants (honeydew honey), which the honeybees search for, convert, combine with their own metabolites, store, dehydrate, and allow to ripen in the honeycombs of the hive [1,2].

This natural elixir shows a very complex chemical composition, roughly consisting of organic (e.g., sugars, proteins, organic acids, vitamins, etc.) and inorganic components, which is strongly influenced by natural and anthropogenic factors [3,4,5,6]. Although inorganic elements make up a minor fraction of honey (typically 0.1–0.2% in floral honey and ≥1% in honeydew honey), they play a key role not only in determining its quality and safety but also in enabling its traceability [7,8]. Conventionally, inorganic elements include macro-elements, such as Na, Ca, Mn, Mg, and K; trace elements, such as Mn, Zn, Fe, Cu, and Se; and potentially toxic elements, such as Ni, Cr, Cd, Pb, As, and Hg. In particular, due to concerns about toxicity, bioaccumulation, and human health risks, potentially toxic elements in food, honey included, have always represented a hot topic for advisory bodies, such as the European Food Safety Authority (EFSA) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA), making them a continuous priority for risk assessment and setting safety limits [9,10,11,12].

Most of the element content in honey comes from the soil and water bodies. Indeed, inorganic elements pass through melliferous plants—acting as intermediate actors—to nectar and then accumulate in honey [13]. Accordingly, the concentration of Na, Ca, Mn, Mg, and K mainly reflects the geochemical and geological characteristics of the soil, rocks, and water surrounding the melliferous area. In honeys from coastal sites and islands, the sea may be a source of K and Na because of the marine aerosol [7,14]. However, the floral source and density, as well as the composition of nectar and pollen, can also be responsible for variations in these metals in honey [15,16]. Hence, the assessment of these metals can be helpful for classifying honey according to its geographical and botanical origin [14,17].

On the other hand, mines, steelworks, highways, and, more generally, industrial and urban areas near the bees’ forage area can strongly influence the concentrations of trace elements and potentially toxic elements, such as Al, Ba, Zn, Fe, Co, Cd, Cr, Cu, Mn, Ni, Pb, Hg and As, in honey [13,18,19,20]. As a result, the profile of trace metals in honey can provide information on the quality of the bees’ forage area, and honey can be considered a reliable marker of environmental pollution [21]. Honey can also be contaminated during its processing due to beekeepers, processing equipment and tools, and the work environment. In fact, trace elements, such as Al, Cd, Co, Cr, Cu, Fe, Pb, Ni, and Zn, can be released from extractors, centrifuges, and containers used for the settling, storage, and shipment of honey [6,8]. The natural acidity of honey (pH 3.5–4.8) also enhances this process by corroding equipment and tool surfaces [13].

In Algeria, beekeeping has gained a relevant socio-economic dimension, thus becoming a valuable source of income for farmers and hobby beekeepers. Indeed, thanks to a series of national programs and subsidies, beekeeping has considerably developed from the 2000s to the present day, with an increase in the number of colonies and, at the same time, the yield of bee products, particularly honey [22,23,24]. Algerian beekeeping is naturally favored by the conducive climate—particularly in the north—and its plant biodiversity, including more than 4000 species. The country is characterized by three distinct environmental and geological zones, namely the Tell, the steppe, and the Sahara. The first two areas define northern Algeria, which is the most devoted to honey production [3,22,23]. Specifically, the Tell territory—consisting of the coastal strip (1600 km) of the Mediterranean Sea, the plains, and the Atlas Mountains—is characterized by hot, dry summers and mild and rainy winters and hosts the most diversified flora of the country, with more than 2500 species. The steppe zone, on the other hand, comprises the highlands between 600 and 1200 m. Here, the climate is drier and arid, resulting in fewer flora (~1100 species) [24]. Overall, the melliferous area in Algeria covers approximately 800,000 hectares and assures the production of a variety of honeys, including eucalyptus (Eucalyptus camaldulensis and E. globulus), orange (Citrus spp.), forest (e.g., Pinus silvestris, Quercus ilex), jujube (Ziziphus lotus and Ziziphus jujuba), sunflower (Helianthus annuus), rosemary (Rosmarinus officinalis), and thyme (Thymus sp.). However, despite its considerable potential, the sector still suffers from several issues, including the absence of regulatory standards, such as those established by the Codex Alimentarius (i.e., Codex Standard for honey 12-1981, Rev.1 Rev.2) and the EU (i.e., Council Directive 2001/110/EC of 20 December 2001 relating to honey and EU Commission Regulation 915/2023) [1,2,25], and official honey inspections. In fact, there are currently no regulatory frameworks or designations of origin that protect Algerian beekeepers and consumers, and, consequently, foreign products are being dumped on local markets, and high-quality honey is not being recognized as such.

Within this context, deepening and updating knowledge of the compositional characteristics of Algerian honey is key not only to evaluate its quality and safety but also to encourage national authorities to take action in response to the current regulatory gaps, with a view to promoting and linking the honey to its production area.

Therefore, this study aims to (1) monitor the content of macro-elements (i.e., Na, K, Mg and Ca), trace elements (Fe, Li, Mn, Co, Cr, Cu, Be, Mo, Se, Ti, and Zn), and potentially toxic elements (Ni, Pb, Sb, Sn, As, Cd, and Hg) of a variety of Algerian honeys; (2) assess their safety based on the current international standards; (3) explore the variability of the element profile in relation to the botanical and geographical origin of investigated honeys; and (4) evaluate their potential toxicological risk to Algerian and EU consumers.

2. Materials and Methods

2.1. Samples

The present study was carried out on honeys produced in North Algeria by different beekeepers during June–December 2024 (Figure 1). Specifically, 36 types of honeys with different botanical and geographical origins were considered. To assure the robustness of the sample set, n = 3 honeys produced from the same apiary but at different times during the semester in question were collected. Hence, a total of n = 108 samples were investigated in this study (

Table 1. Information on Algerian honey samples.

Apiary Code	N. Honey Sample	Geographical Origin	Botanical Origin
HS-1	1	Tizi Ouzou	Pinus silvestris
	2
	3
HS-2	4	Laghouat	Ziziphus lotus
	5
	6
HS-3	7	Djelfa	Ziziphus lotus–Silybum marianum
	8
	9
HS-4	10	Tissemsilt	Tamarix africana
	11
	12
HS-5	13	Blida	Citrus sinensis
	14
	15
HS-6	16	Laghouat	Euphorbia officinarum
	17
	18
HS-7	19	Tizi Ouzou	Quercus ilex–Eucalyptus globulus
	20
	21
HS-8	22	Djelfa	Nasturtium officinalis
	23
	24
HS-9	25	Touggourt	Helianthus annuus
	26
	27
HS-10	28	Annaba	Eucalyptus globulus
	29
	30
HS-11	31	Tizi Ouzou	Quercus ilex
	32
	33
HS-12	34	Tizi Ouzou	Nasturtium officinalis
	35
	36
HS-13	37	Skikda	Eucalyptus globulus
	38
	39
HS-14	40	Tebessa	Rosmarinus officinalis
	41
	42
HS-15	43	Tizi Ouzou	Ceratonia siliqua
	44
	45
HS-16	46	Djelfa	Multifloral
	47
	48
HS-17	49	Chlef	Ziziphus lotus–Thymus vulgaris
	50
	51
HS-18	52	Blida	Citrus sinensis
	53
	54
HS-19	55	El Bayadh	Euphorbia officinarum
	56
	57
HS-20	58	Djelfa	Silybum marianum
	59
	60
HS-21	61	Djelfa	Eruca sativa
	62
	63
HS-22	64	Ain Defla	Pinus halepensis–Quercus ilex
	65
	66
HS-23	67	Mostaganem	Multifloral
	68
	69
HS-24	70	Tiaret	Eruca sativa
	71
	72
HS-25	73	Relizane	Ziziphus lotus
	74
	75
HS-26	76	Naâma	Multifloral
	77
	78
HS-27	79	Skikda	Citrus sinensis
	80
	81
HS-28	82	Tiaret	Multifloral
	83
	84
HS-29	85	Mostaganem	Citrus sinensis
	86
	87
HS-30	88	Tebessa	Ziziphus lotus
	89
	90
HS-31	91	Mascara	Tamarix africana
	92
	93
HS-32	94	Tizi Ouzou	Erica arborea–Lavandula stoechas
	95
	96
HS-33	97	Mostaganem	Eucalyptus gomphocephala
	98
	99
HS-34	100	Mostaganem	Pinus halepensis–Rosmarinus officinalis
	101
	102
HS-35	103	Mostaganem	Citrus sinensis
	104
	105
HS-36	106	Chlef	Multifloral
	107
	108

). The botanical and geographical origin of all honey samples was declared based on information provided by the beekeepers and the nutritional labels. In addition, the botanical origin of honeys was experimentally determined according to the protocol reported by Zerrouk & Bahloul [26] and by exploiting a reference pollen collection housed in the Institute of Natural and Life Sciences of the University Center Nour El Bachir El Bayadh (El Bayadh, Algeria). Honeys were categorized as “monofloral” when a pollen species was at a predominant percentage (≥45%), “bifloral” when two pollen types were at secondary percentages (15–45%), and “multifloral” when ≥3 pollen species were determined with secondary percentages. The consistency between the declared information and the experimental outcome was assessed in all samples.

Honey samples were always collected in dark glass containers, labeled with date and site of production, transported, and kept at room temperature until analysis.

2.2. Reagents and Materials

Reagents such as HNO₃ (69%) and H₂O₂ (30%) were of Suprapur grade and supplied by J.T. Baker (Milan, Italy). Ultrapure water (<5 mg/L TOC) was obtained with a Barnstead Smart2Pure 12 water purification system (Thermo Scientific, Milan, Italy). For the ICP-MS analysis, single-element standard solutions of As, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Sn, Ti and Zn (1000 mg/L in 2% HNO₃), along with a solution of the internal standard Re (1000 mg/L in 2% HNO₃), were purchased from Fluka (Milan, Italy). An Hg solution (1000 mg/L in 3% HCl) was supplied by Merck (Darmstadt, Germany). To avoid metal cross-contamination, glassware and stainless-steel tools were always washed with acetone, rinsed with hexane, dried at 400 °C for at least 4 h, and finally wrapped with aluminum foil until analysis.

2.3. Sample Preparation and Analysis

To prepare the honey samples for subsequent ICP-MS analysis, acid digestion was first carried out by using an ETHOS 1 microwave digestion system (Milestone, Bergamo, Italy).

The mineralization procedure followed the protocol already reported in our previous work [27]. Approximately 0.5 g of each sample was first added with 1 mL of internal standard Re at a concentration of 0.5 mg/L, followed by 7 mL of 65% HNO₃ and 1 mL of 30% H₂O₂. The mineralization occurred with a constant microwave power of 1000 W and consisted of 3 steps: first, the temperature was increased to 200 °C for 15 min; then, it was kept constant at 200 °C for another 15 min; finally, the samples were left to cool to room temperature for 20 min. The digested samples were diluted with ultrapure water to a final volume of 25 mL and filtered through 0.45 μm filters. Blank solutions were processed in the same way.

The elemental content of all samples was determined using the iCAP-Q ICP-MS (Thermo Scientific, Waltham, MA, USA). In detail, the following elements have been determined: ⁷Li, ⁹Be, ²³Na, ²⁴Mg, ³⁹K, ⁴⁰Ca, ⁴⁸Ti, ⁵²Cr, ⁵⁵Mn, ⁵⁶Fe, ⁵⁹Co, ⁶⁰Ni, ⁶³Cu, ⁶⁶Zn, ⁷⁵As, ⁸⁰Se, ⁹⁸Mo, ¹¹⁴Cd, ¹²⁰Sn, ¹²¹Sb, and ²⁰⁸Pb. The operating conditions of the ICP-MS method were already reported in our previous studies [3,27] and are listed in

Table 2. Operating conditions of the ICP-MS method.

Parameter	Setting
Nebulizer	Concentric PFA
RF-generator	1550 W
Sample depth	5 mm
Interface	Sample and skimmer cones in Ni
Interface pressure	1.89 × 100 Pa
Argon flow (plasma/auxiliary/carrier)	14/0.8/1.1 L/min
Sample introduction flow	0.93 L/min
Scanning condition	Number of replicates: 3, dwell time: 1 s
CCT gas flow (He)	4.7 mL/min
Vacuum	<7.5 × 10−7 Pa
Extract Lens 1 voltage	1.5 V
Spray chamber temperature	2.7 °C
Integration times	0.5 s/point for As, Se, and Fe; 0.1 s/point for other elements

.

Various interferences (e.g., mono- and polyatomic ions) may affect the reliability of the ICP-MS measurements. However, thanks to the integrated Q-Cell system provided with a low-mass cutting feature, the iCAP-Q instrument is able to remove or significantly contain the interferences generated by lower-mass precursor ions.

For the determination of Hg in honey, around 0.1 g of every honey sample was simply dried at 290 °C for 3 min and then analyzed by the direct mercury analyzer (DMA-80, Milestone, Bergamo, Italy) exploiting the principle of thermal decomposition amalgamation–atomic absorption spectrophotometry (TDA-AAS). The analytical conditions followed the EPA 7473 guidelines [28] and our previous study [3].

Every honey sample was analyzed in triplicate, along with analytical blanks.

For the validation procedure, standard solutions of target analytes were prepared and suitably diluted. In the absence of certified matrices, internal reference material, namely, biological multifloral honey, was used to validate the trueness of the analytical methods.

As required by the Eurachem guidelines [29], both ICP-MS and DMA-80 methods were evaluated in terms of the following:

• Linearity: Stock multi-element standard solutions were prepared and suitably diluted to construct seven-point calibration curves. For each point of the curve, six replicates (n = 6) were analyzed. Correlation coefficients (R²) were used to check the linearity of the calibration curves. The linear ranges were 0.5–200.0 μg/L for As, Be, Cd, Cr, Li, Mo, Ni, Pb, Sb, Co, Cu, Fe, Mn, Se, Sn, Ti, and Zn; 0.1–5.0 mg/L for K, Ca, Na, and Mg; and 1–100 μg/L for Hg.
• Sensitivity: The limit of detection (LOD) and limit of quantification (LOQ) were determined for each target analyte. They were determined as 3.3 σ/S and 10 σ/S, respectively, where σ is the standard deviation of the mean value obtained by the analysis of ten blanks and S is the slope of the relative calibration curve.
• Trueness: An internal honey sample was first prepared and analyzed through the procedure described above and then spiked at three known concentration levels (i.e., 0.1, 0.2, and 0.5 mg/kg for Pb, Ni, Cr, Sb, As, Cd, Sn and Hg; 0.2, 1.0, and 2.0 mg/kg for Fe, Li, Be, Zn, Se, Ti, Mn, Mo, Cu, and Co; and 0.2, 0.5, and 1.0 g/kg for Ca, Na, Mg, and K) and re-analyzed. Hence, the trueness was calculated by considering both the experimental concentrations of the element derived from the sample analysis and the known amount of the standard spiked to the sample. Results are reported as the mean %value, averaged across the three different concentration levels, each replicated three times.
• Precision: Intraday and interday precision were evaluated for each element by analyzing six replicates of the honey sample spiked at the lowest concentration levels on the same day and over a longer period (i.e., one week). Results are reported as RSD%, averaged across the replicate measurements

The validation procedure conducted for every target analyte is shown in

Table 3. Analytical validation of ICP-MS and TDA-AAS methods employed for the analysis of Algerian honeys. Validation was conducted in terms of linearity (R²), limit of detection (LOD), limit of quantification (LOQ), trueness (n = 9 replicate measurements), and precision (n = 6 replicate measurements).

Element	R2	LOD (mg/kg)	LOQ (mg/kg)	Trueness (%)	Precision (RSD%)
					Intraday	Interday
As	0.9996	0.001	0.003	98.00	1.4	1.5
Be	0.9996	0.003	0.010	96.50	1.1	1.2
Ca	0.9989	0.095	0.314	91.50	1.1	1.3
Cd	0.9998	0.001	0.003	100.50	1.0	1.2
Co	0.9995	0.003	0.010	96.25	0.9	1.1
Cr	0.9998	0.003	0.010	95.50	0.7	0.8
Cu	0.9997	0.005	0.017	97.75	0.9	1.0
Fe	0.9995	0.010	0.033	96.10	0.6	0.7
K	0.9988	0.105	0.347	90.25	1.1	1.2
Li	0.9996	0.003	0.010	96.80	1.0	1.2
Mg	0.9994	0.070	0.231	97.50	1.1	1.3
Mn	0.9995	0.004	0.013	97.35	1.2	1.4
Mo	0.9996	0.003	0.010	97.15	1.0	1.1
Na	0.9989	0.085	0.281	92.00	0.8	0.9
Ni	0.9994	0.003	0.010	98.85	1.0	1.3
Pb	0.9999	0.001	0.003	102.50	0.7	0.8
Sb	0.9993	0.003	0.010	97.00	1.0	1.1
Se	0.9995	0.004	0.013	94.50	1.1	1.3
Sn	0.9993	0.003	0.010	97.25	1.2	1.3
Ti	0.9995	0.003	0.010	96.00	0.9	1.0
Zn	0.9997	0.010	0.033	97.15	1.2	1.3
Hg	0.9998	0.003	0.010	98.00	0.9	1.0

.

2.4. Statistical Analysis

The SPSS 19.0 software package for Windows (SPSS Inc., Chicago, IL, USA) was used to analyze the significance of the results.

In Tables 5–7, experimental data are expressed as mean ± standard deviation of n = 3 honeys from the same apiary (HS-1–HS-36), where every honey was analyzed three times. The calculated %RSD for samples from the same apiary was constantly <5%, thus confirming good within-apiary replicability. Table S1 provides all the raw data from the 108 samples.

The input of statistical analysis was a data matrix constituted by n = 108 honey samples analyzed over the study period and the experimental element concentrations. Specifically, the data set did not include elements such as As, Be, Li, Mo, Sb, or Hg, since their concentrations were below the relative LOQ in >50% of the tested samples. On the other hand, for those elements whose content was below the LOQ in <50% of samples, a concentration value of LOD/2 was assigned.

The differences between honeys (n = 108 samples) based on geographical origin were evaluated using the non-parametric Mann–Whitney U-test, which was applied to log-transformed data, and a statistical significance at p < 0.05 was accepted (Table 6). On the other hand, the non-parametric Kruskal–Wallis test was used to analyze the log-transformed data to identify differences between the honeys (n = 108 samples) based on their botanical origin (Table 7). The statistical significance was set at p < 0.05.

Moreover, a principal component analysis (PCA) was conducted to explore the sample differentiation with respect to the botanical and geographical provenance. To attain independence of the element concentrations from the scale factors of the different variables, the data set was first normalized. Then, the eligibility of the data for PCA was verified by the Kaiser–Meyer–Olkin (KMO) and Bartlett tests. The first test was run to evaluate the sampling adequacy through the KMO score. Specifically, the KMO score can range from 0 to 1; a score > 0.8 shows that the data set is highly suitable for analysis. Values between 0.6 and 0.8 indicate that experimental data have a good suitability, while scores < 0.6 are obtained for an unacceptable data set, suggesting a need to collect more data or remove variables.

Bartlett’s test, also known as the sphericity test, was employed to test the null hypothesis that the correlation matrix of the investigated variables is an identity matrix. In other words, all the diagonal values of the correlation matrix are equal to 1, and the rest of the values are equal to 0; no correlation exists between the element concentrations. Once the data suitability was tested, the PCA was carried out to reduce data dimensionality while identifying the combinations of the variables that provide the largest contribution to sample variability, commonly known as principal components (PCs). Accounting for a greater portion of the variance in the data set and having the largest eigenvalues, the first PCs are typically used for proper sample differentiation. However, the Kaiser criterion was used to reliably determine the number of PCs to retain in PCA by keeping only those PCs with an eigenvalue > 1.

2.5. Toxicological Risk Assessment

The estimated daily intake (EDI) was calculated to determine the quality and safety of Algerian honeys. The following formula was used:

EDI = C × I

in which C is the average concentration of inorganic element found in each sample, expressed in mg/kg, while I is the amount of honey consumed per day (0.3 g/person/day for North Africa, 1.8 g/person/day for Europe), according to FAOSTAT [30].

The resulting EDI values were then compared with the reference values for essential nutrients from Directive 1169/2001 and EFSA [31,32].

In the case of potentially toxic elements, the following formula was used to calculate the EDI values:

EDI = (C × I)/Kg_b.w.

where Kg_b.w. is the consumer’s average weight (70 kg). Also, for this type of inorganic element, the comparison between the obtained EDIs and the international reference safety values was carried out [33,34,35,36,37,38,39,40,41,42,43].

The plausibility of the chronic non-carcinogenic risk was assessed using the hazard quotient (HQ) [44] as follows:

HQ = EDI/RfD

where EDI is the estimated daily dose and RfD is the reference oral dose proposed by the US Environmental Protection Agency (US EPA) [45]. The values of the elements of interest are given in

Table 4. Reference oral doses (RfDs) proposed by the US EPA for various inorganic elements.

Element	RfD (μg/Kgbw/Day)
As	0.3
Cd	1
Cr	3
Cu	40
Fe	9
Mn	140
Ni	20
Pb	3.5
Zn	300

. If the HQ value is less than 1, the non-cancer risk is low.

3. Results

3.1. Profile of Inorganic Elements in Algerian Honeys

The profiles of inorganic elements revealed in the different Algerian honeys are shown in

Table 5. Content of inorganic elements (mg/kg) in Algerian honeys. Results are expressed as mean ± standard deviation of n = 3 honeys from the same apiary (HS-1–HS-36), where every honey was analyzed three times. The table does not list Sb, Be, Li, and Mo, as they were below the limit of quantification (LOQ) in all samples.

Samples	Macro-Elements				Trace Elements								Potentially Toxic Elements
	Na	Ca	Mg	K	Fe	Co	Cr	Cu	Mn	Se	Ti	Zn	Sn	As	Cd	Ni	Pb	Hg
HS-1	82.90 ± 2.63	273.31 ± 3.49	107.37 ± 2.18	614.59 ± 3.36	14.83 ± 0.23	0.03 ± 0.01	0.06 ± 0.01	1.25 ± 0.09	3.64 ± 0.41	0.23 ± 0.03	0.19 ± 0.03	3.50 ± 0.23	<LOQ	<LOQ	0.02 ± 0.01	0.11 ± 0.03	0.02 ± 0.01	<LOQ
HS-2	54.84 ± 3.88	95.31 ± 3.23	71.05 ± 4.08	11,504.46 ± 241.40	18.27 ± 0.23	<LOQ	0.13 ± 0.02	0.60 ± 0.04	0.10 ± 0.01	0.38 ± 0.04	<LOQ	9.28 ± 0.23	0.14 ± 0.01	<LOQ	1.02 ± 0.05	0.31 ± 0.05	0.64 ± 0.10	<LOQ
HS-3	45.37 ± 3.82	158.33 ± 8.24	31.31 ± 2.42	1606.19 ± 41.83	6.52 ± 0.33	0.50 ± 0.05	0.26 ± 0.03	0.72 ± 0.05	0.23 ± 0.02	0.37 ± 0.03	0.04 ± 0.01	1.77 ± 0.12	0.03 ± 0.01	<LOQ	0.05 ± 0.01	0.41 ± 0.03	0.19 ± 0.02	<LOQ
HS-4	89.12 ± 1.89	278.40 ± 4.81	34.81 ± 3.17	820.01 ± 4.28	10.02 ± 0.17	<LOQ	0.09 ± 0.01	3.67 ± 0.10	4.27 ± 0.14	0.12 ± 0.02	0.28 ± 0.04	1.05 ± 0.08	0.06 ± 0.01	0.02 ± 0.01	0.09 ± 0.01	0.34 ± 0.03	0.12 ± 0.02	<LOQ
HS-5	118.51 ± 4.55	314.40 ± 8.40	82.65 ± 1.92	924.10 ± 9.57	9.17 ± 0.08	0.20 ± 0.03	0.21 ± 0.05	2.77 ± 0.21	1.23 ± 0.11	0.35 ± 0.03	0.49 ± 0.05	14.65 ± 0.63	<LOQ	0.06 ± 0.02	0.28 ± 0.04	0.26 ± 0.05	0.71 ± 0.05	<LOQ
HS-6	46.31 ± 2.65	97.74 ± 2.54	79.15 ± 2.88	12,606.41 ± 323.81	19.07 ± 1.85	<LOQ	0.15 ± 0.01	0.51 ± 0.05	0.16 ± 0.02	0.34 ± 0.04	<LOQ	8.59 ± 0.46	0.08 ± 0.02	<LOQ	0.81 ± 0.03	0.32 ± 0.05	0.52 ± 0.04	<LOQ
HS-7	64.58 ± 3.02	286.79 ± 4.12	108.15 ± 1.36	643.41 ± 4.68	14.34 ± 0.30	0.03 ± 0.01	0.09 ± 0.02	1.35 ± 0.07	3.41 ± 0.18	0.21 ± 0.02	0.22 ± 0.03	3.88 ± 0.21	<LOQ	<LOQ	0.02 ± 0.01	0.14 ± 0.02	0.04 ± 0.01	<LOQ
HS-8	50.50 ± 2.78	195.70 ± 4.50	35.36 ± 2.27	1526.11 ± 26.15	5.84 ± 0.16	0.47 ± 0.02	0.18 ± 0.03	0.80 ± 0.06	0.27 ± 0.02	0.34 ± 0.02	0.02 ± 0.01	1.58 ± 0.10	0.04 ± 0.01	<LOQ	0.04 ± 0.00	0.41 ± 0.04	0.20 ± 0.03	<LOQ
HS-9	64.03 ± 3.17	192.13 ± 4.92	142.67 ± 4.96	1054.08 ± 24.93	5.15 ± 0.14	0.38 ± 0.05	0.13 ± 0.02	0.53 ± 0.09	0.49 ± 0.06	0.28 ± 0.03	0.04 ± 0.01	1.27 ± 0.05	0.02 ± 0.00	<LOQ	0.03 ± 0.01	0.23 ± 0.03	0.24 ± 0.02	<LOQ
HS-10	161.80 ± 3.20	380.28 ± 7.99	106.79 ± 6.84	659.92 ± 14.67	16.74 ± 1.02	0.32 ± 0.04	0.15 ± 0.03	1.74 ± 0.17	2.23 ± 0.07	0.17 ± 0.03	0.33 ± 0.02	9.94 ± 0.17	<LOQ	0.03 ± 0.01	0.43 ± 0.04	0.19 ± 0.03	0.86 ± 0.04	0.04 ± 0.01
HS-11	58.45 ± 2.22	270.62 ± 1.71	128.88 ± 4.48	591.31 ± 3.96	14.10 ± 0.14	0.02 ± 0.01	0.06 ± 0.01	1.22 ± 0.05	3.55 ± 0.23	0.23 ± 0.02	0.20 ± 0.03	3.43 ± 0.25	<LOQ	<LOQ	0.04 ± 0.01	0.13 ± 0.03	0.05 ± 0.01	<LOQ
HS-12	72.17 ± 1.90	283.32 ± 2.13	122.55 ± 14.90	610.92 ± 5.34	13.16 ± 0.31	0.02 ± 0.01	0.09 ± 0.01	1.38 ± 0.06	3.96 ± 0.06	0.25 ± 0.04	0.24 ± 0.02	4.15 ± 0.11	<LOQ	<LOQ	0.01 ± 0.01	0.15 ± 0.03	0.07 ± 0.02	<LOQ
HS-13	173.68 ± 3.71	334.11 ± 4.40	191.08 ± 4.48	718.46 ± 6.38	19.61 ± 0.59	0.43 ± 0.02	0.18 ± 0.02	3.20 ± 0.15	2.65 ± 0.11	0.23 ± 0.02	0.41 ± 0.02	14.19 ± 0.20	<LOQ	0.05 ± 0.01	0.47 ± 0.05	0.31 ± 0.02	0.91 ± 0.03	0.05 ± 0.01
HS-14	98.58 ± 7.45	412.99 ± 8.27	93.21 ± 8.23	601.78 ± 10.36	10.75 ± 0.12	0.16 ± 0.03	0.13 ± 0.02	2.94 ± 0.22	4.16 ± 0.16	0.16 ± 0.01	0.23 ± 0.02	16.80 ± 0.51	<LOQ	<LOQ	0.22 ± 0.02	0.35 ± 0.04	0.81 ± 0.03	<LOQ
HS-15	70.96 ± 4.90	295.49 ± 1.83	156.47 ± 7.25	675.74 ± 4.16	15.90 ± 0.30	0.02 ± 0.01	0.11 ± 0.02	2.61 ± 0.06	6.25 ± 0.31	0.41 ± 0.04	0.19 ± 0.03	6.24 ± 0.55	<LOQ	<LOQ	0.03 ± 0.01	0.19 ± 0.04	0.04 ± 0.01	<LOQ
HS-16	51.37 ± 3.37	178.34 ± 7.86	44.00 ± 3.37	1620.35 ± 26.52	6.13 ± 0.12	0.56 ± 0.03	0.25 ± 0.05	0.63 ± 0.06	0.24 ± 0.05	0.39 ± 0.04	0.04 ± 0.01	1.47 ± 0.07	0.02 ± 0.01	<LOQ	0.05 ± 0.01	0.42 ± 0.04	0.24 ± 0.03	<LOQ
HS-17	107.11 ± 4.01	341.11 ± 5.29	62.63 ± 2.23	777.28 ± 5.62	13.83 ± 0.72	<LOQ	0.13 ± 0.02	4.30 ± 0.22	5.19 ± 0.06	0.19 ± 0.01	0.32 ± 0.03	1.75 ± 0.11	0.09 ± 0.01	0.03 ± 0.01	0.12 ± 0.03	0.43 ± 0.02	0.25 ± 0.04	<LOQ
HS-18	118.91 ± 8.16	315.34 ± 3.92	72.50 ± 2.53	924.89 ± 4.68	8.93 ± 0.16	0.21 ± 0.04	0.23 ± 0.03	2.68 ± 0.12	1.20 ± 0.06	0.33 ± 0.04	0.47 ± 0.03	14.15 ± 0.23	<LOQ	0.08 ± 0.02	0.33 ± 0.05	0.28 ± 0.06	0.61 ± 0.04	<LOQ
HS-19	775.48 ± 7.28	404.90 ± 7.44	675.71 ± 4.45	9625.49 ± 29.87	42.04 ± 1.67	1.40 ± 0.05	0.95 ± 0.03	1.65 ± 0.05	4.84 ± 0.11	0.45 ± 0.03	1.55 ± 0.04	2.24 ± 0.09	<LOQ	0.01 ± 0.00	0.05 ± 0.01	0.53 ± 0.04	0.69 ± 0.06	<LOQ
HS-20	49.75 ± 3.24	154.77 ± 5.81	24.25 ± 1.87	1691.98 ± 30.10	5.39 ± 0.14	0.67 ± 0.06	0.28 ± 0.03	0.84 ± 0.06	0.22 ± 0.03	0.31 ± 0.02	0.04 ± 0.01	1.87 ± 0.09	0.04 ± 0.01	<LOQ	0.07 ± 0.02	0.40 ± 0.04	0.18 ± 0.03	<LOQ
HS-21	57.94 ± 2.70	173.45 ± 4.09	32.90 ± 3.18	1640.29 ± 10.57	6.59 ± 0.17	0.63 ± 0.04	0.18 ± 0.03	0.81 ± 0.07	0.28 ± 0.05	0.38 ± 0.05	0.03 ± 0.00	1.80 ± 0.09	0.04 ± 0.01	<LOQ	0.05 ± 0.01	0.44 ± 0.04	0.15 ± 0.02	<LOQ
HS-22	97.30 ± 1.79	311.91 ± 6.69	165.74 ± 6.09	807.77 ± 4.42	11.16 ± 0.39	<LOQ	0.08 ± 0.01	3.49 ± 0.06	4.38 ± 0.06	0.11 ± 0.02	0.22 ± 0.03	1.35 ± 0.11	0.04 ± 0.01	0.01 ± 0.00	0.10 ± 0.03	0.34 ± 0.02	0.18 ± 0.03	<LOQ
HS-23	176.29 ± 5.24	206.49 ± 4.17	99.28 ± 7.50	929.50 ± 4.47	16.80 ± 0.96	0.03 ± 0.01	0.05 ± 0.02	5.10 ± 0.06	6.33 ± 0.21	0.25 ± 0.03	0.46 ± 0.03	2.77 ± 0.09	0.12 ± 0.02	<LOQ	<LOQ	0.19 ± 0.03	0.04 ± 0.01	<LOQ
HS-24	80.14 ± 3.19	114.52 ± 3.62	48.06 ± 1.36	773.56 ± 14.57	14.49 ± 0.97	0.04 ± 0.01	0.36 ± 0.03	5.37 ± 0.17	6.17 ± 0.17	0.16 ± 0.01	0.86 ± 0.06	8.06 ± 0.19	0.13 ± 0.02	0.06 ± 0.01	0.35 ± 0.03	0.31 ± 0.03	0.70 ± 0.05	<LOQ
HS-25	60.22 ± 3.41	285.57 ± 7.54	47.18 ± 3.60	462.10 ± 25.89	8.70 ± 0.46	0.31 ± 0.04	0.09 ± 0.01	0.99 ± 0.08	3.04 ± 0.23	0.21 ± 0.02	0.12 ± 0.03	4.38 ± 0.27	0.01 ± 0.01	0.03 ± 0.01	0.07 ± 0.02	0.07 ± 0.02	0.09 ± 0.02	0.02 ± 0.01
HS-26	861.90 ± 35.31	429.31 ± 7.31	124.02 ± 3.93	13,337.56 ± 233.94	35.78 ± 2.18	0.80 ± 0.05	0.57 ± 0.04	1.79 ± 0.07	3.02 ± 0.12	0.62 ± 0.04	2.35 ± 0.09	5.22 ± 0.19	<LOQ	0.02 ± 0.01	0.07 ± 0.01	0.51 ± 0.03	0.73 ± 0.03	<LOQ
HS-27	175.58 ± 3.60	354.96 ± 7.07	201.20 ± 5.24	741.64 ± 8.43	19.84 ± 0.33	0.45 ± 0.04	0.17 ± 0.02	3.27 ± 0.15	2.73 ± 0.06	0.23 ± 0.02	0.41 ± 0.03	14.04 ± 0.18	<LOQ	0.05 ± 0.00	0.46 ± 0.04	0.31 ± 0.01	0.98 ± 0.03	0.04 ± 0.01
HS-28	69.34 ± 1.85	97.41 ± 2.81	56.41 ± 2.54	771.53 ± 7.35	14.34 ± 1.18	0.06 ± 0.01	0.40 ± 0.03	0.79 ± 0.03	0.05 ± 0.01	0.21 ± 0.02	0.74 ± 0.04	12.86 ± 0.55	0.19 ± 0.04	0.13 ± 0.01	1.18 ± 0.10	0.38 ± 0.03	0.75 ± 0.03	<LOQ
HS-29	190.06 ± 4.07	272.13 ± 20.48	82.87 ± 1.93	896.60 ± 6.40	19.34 ± 0.21	0.03 ± 0.01	0.04 ± 0.01	5.07 ± 0.08	7.13 ± 0.10	0.23 ± 0.03	0.45 ± 0.04	2.97 ± 0.08	0.13 ± 0.02	<LOQ	<LOQ	0.21 ± 0.03	0.03 ± 0.01	<LOQ
HS-30	93.94 ± 2.27	435.32 ± 10.76	100.78 ± 4.49	614.44 ± 8.12	10.77 ± 0.30	0.20 ± 0.02	0.13 ± 0.02	2.83 ± 0.15	4.17 ± 0.07	0.16 ± 0.02	0.24 ± 0.02	17.02 ± 0.12	<LOQ	<LOQ	0.23 ± 0.03	0.39 ± 0.02	0.84 ± 0.05	<LOQ
HS-31	125.96 ± 5.73	83.46 ± 1.59	104.16 ± 1.26	380.34 ± 2.75	28.31 ± 0.73	<LOQ	0.03 ± 0.01	5.30 ± 0.17	8.94 ± 0.15	0.14 ± 0.02	0.26 ± 0.05	3.21 ± 0.10	0.08 ± 0.02	<LOQ	<LOQ	0.11 ± 0.03	0.01 ± 0.01	<LOQ
HS-32	77.13 ± 1.09	257.00 ± 2.23	97.34 ± 6.47	650.52 ± 4.37	15.15 ± 0.47	0.04 ± 0.01	0.11 ± 0.02	1.20 ± 0.07	4.13 ± 0.13	0.25 ± 0.03	0.17 ± 0.02	3.61 ± 0.16	<LOQ	<LOQ	0.03 ± 0.01	0.09 ± 0.03	0.10 ± 0.03	<LOQ
HS-33	175.59 ± 4.47	193.90 ± 5.95	107.31 ± 11.56	962.06 ± 10.85	19.63 ± 0.77	0.01 ± 0.01	0.04 ± 0.01	6.06 ± 0.41	5.94 ± 0.17	0.25 ± 0.04	0.48 ± 0.06	4.01 ± 0.10	0.11 ± 0.03	<LOQ	<LOQ	0.19 ± 0.03	0.03 ± 0.01	<LOQ
HS-34	163.66 ± 3.72	216.95 ± 5.22	83.25 ± 2.52	910.41 ± 7.81	18.22 ± 0.30	0.02 ± 0.01	0.05 ± 0.01	4.92 ± 0.05	6.74 ± 0.10	0.26 ± 0.03	0.45 ± 0.04	3.44 ± 0.12	0.12 ± 0.03	<LOQ	<LOQ	0.21 ± 0.04	0.03 ± 0.01	<LOQ
HS-35	172.57 ± 12.38	231.01 ± 7.16	92.66 ± 4.10	830.81 ± 17.88	18.57 ± 0.18	0.01 ± 0.01	0.04 ± 0.01	5.42 ± 0.22	6.61 ± 0.14	0.23 ± 0.04	0.42 ± 0.04	2.52 ± 0.12	0.14 ± 0.03	<LOQ	<LOQ	0.18 ± 0.02	0.02 ± 0.01	<LOQ
HS-36	114.40 ± 3.86	377.39 ± 6.11	67.97 ± 2.78	788.17 ± 4.05	13.86 ± 0.29	<LOQ	0.13 ± 0.02	4.56 ± 0.13	5.20 ± 0.06	0.20 ± 0.01	0.31 ± 0.03	1.80 ± 0.05	0.09 ± 0.01	0.03 ± 0.01	0.15 ± 0.03	0.44 ± 0.04	0.24 ± 0.04	<LOQ
Regulatory limits	-	-	25.00 a	-	15.00 a	-	-	5.00 a	-	-	-	5.00 a	-	0.01–0.5 a	0.05 a	-	0.10 b	-

LOQ: Limit of quantification. Regulatory limits: ^a: Codex Standard for honey 12-1981, Rev.2; ^b: EU Commission Regulation 2023/915.

.

Regarding macro-elements, they were found in the following quantitative order: K (mean: 2091.52 mg/kg) > Ca (mean: 258.45 mg/kg) > Na (mean: 140.18 mg/kg) > Mg (mean: 107.83 mg/kg).

On the other hand, the most abundant micro-element was Fe (mean: 15.04 mg/kg), followed by Zn (mean: 5.86 mg/kg), Mn (mean: 3.42 mg/kg), and Cu (mean: 2.57 mg/kg). The presence of Se and Cr was also confirmed in all honey samples, with a mean concentration of 0.27 mg/kg and 0.29 mg/kg, respectively. Almost all the samples had a quantifiable content of Co (81% of total samples with a mean content of 0.28 mg/kg) and Ti (94% of total samples with a mean content of 0.39 mg/kg).

Considering the potentially toxic elements, Pb and Ni were found in all samples, with concentrations of 0.34 mg/kg and 0.29 mg/kg, respectively. On the other hand, Sn was above the LOQ in 58% of total samples and ranged from 0.01 ± 0.01 mg/kg to 0.19 ± 0.04 mg/kg (HS-28). Cd was quantified in 83% of samples from 0.01 ± 0.00 mg/kg (sample HS-19) to 0.13 ± 0.01 mg/kg (sample HS-28), while Hg was measured only in 11% of samples with a content between 0.02 ± 0.01 and 0.05 ± 0.01 mg/kg (samples HS-25 and HS-13, respectively). Finally, the Sb, Be, Li, and Mo content in all analyzed samples was below the relative LOQs.

3.2. Comparison of Inorganic Elements in Honeys from Coastal and Non-Coastal Areas

Table 6. Content of inorganic elements (mg/kg) in honey samples based on their geographical provenance. Results are expressed as mean ± standard deviation of n = 42 honeys from the coastal areas and n = 66 honeys from the non-coastal areas of northern Algeria.

Element	Honeys from the Coastal Area (n = 42)	Honeys from the Non-Coastal Area (n = 66)	p-Value
Ca	275.45 ± 5.20 a	247.63 ± 5.72 a	0.205
Cd	0.17 ± 0.02 a	0.26 ± 0.02 b	0.000
Co	0.10 ± 0.01 a	0.44 ± 0.04 a	0.070
Cr	0.09 ± 0.01 a	0.23 ± 0.02 b	0.000
Cu	3.13 ± 0.11 a	2.21 ± 0.10 b	0.002
Fe	16.87 ± 0.41 a	13.87 ± 0.57 b	0.000
K	745.42 ± 6.85 a	2948.13 ± 49.58 b	0.000
Mg	120.37 ± 5.39 a	99.84 ± 3.34 b	0.000
Mn	4.67 ± 0.15 a	2.63 ± 0.08 b	0.000
Na	129.67 ± 3.74 a	146.86 ± 5.29 b	0.000
Ni	0.18 ± 0.02 a	0.35 ± 0.03 b	0.000
Pb	0.23 ± 0.01 a	0.41 ± 0.03 b	0.000
Se	0.25 ± 0.03 a	0.28 ± 0.02 a	0.496
Sn	0.12 ± 0.02 a	0.07 ± 0.01 a	0.079
Ti	0.33 ± 0.03 a	0.43 ± 0.03 b	0.041
Zn	5.62 ± 0.17 a	6.01 ± 0.20 a	0.076

^a,b: Different superscript letters in the same row indicate significantly different values (p ≤ 0.05 by Mann–Whitney U-test); same superscript letters in the same column indicate non-significantly different values (p > 0.05 by Mann–Whitney U-test). Honeys from coastal areas: HS-1 (1–3), HS-7 (19–21), HS-10 (28–30), HS-11 (31–33), HS-12 (34–36), HS-13 (37–39), HS-15 (43–45), HS-23 (67–69), HS-27 (79–81), HS-29 (85–87), HS-32 (94–96), HS-33 (97–99), HS-34 (100–102), and HS-35 (103–105); honeys from non-coastal areas: HS-2 (4–6), HS-3 (7–9), HS-4 (10–12), HS-5 (13–15), HS-6 (16–18), HS-8 (22–24), HS-9 (25–27), HS-14 (40–42), HS-16 (46–48), HS-17 (49–51), HS-18 (52–54), HS-19 (55–57), HS-20 (58–60), HS-21 (61–63), HS-22 (64–66), HS-24 (70–72), HS-25 (73–75), HS-26 (76–78), HS-28 (82–84), HS-30 (88–90), HS-31 (91–93), and HS-36 (106–108).

shows the mean content of inorganic elements in northern Algerian honeys classified based on their site of production, namely coastal areas, such as Annaba, Skikda, Mostaganem, and Tizi Ouzou (n = 42 honeys), and non-coastal areas, such as Mascara, Relizane, Tiaret, Chlef, Ain Defla, Tissemsilt, Blida, Naama, El Bayadh, Laghouat, Djelfa, Touggourt, and Tebessa (n = 66 honeys). Analytes such as Li, Mo, Be, Sb, As, and Hg are not listed, since only elements quantified in at least 50% of the samples are included in Table 5.

As shown by the low p-value of 0.000 (Table 6), honeys from the non-coastal area had a significantly higher K content than the coastal counterpart (2948.13 ± 49.58 mg/kg vs. 745.42 ± 6.85 mg/kg). The same trend was observed for other macro-elements, such as Na (146.86 ± 5.29 mg/kg vs. 129.67 ± 3.74 mg/kg) and Mg (120.37 ± 5.39 mg/kg vs. 99.84 ± 3.34 mg/kg), with p-values of 0.000 (Table 5). However, the difference in Ca content between the two areas was not statistically significant (275.45 ± 5.20 mg/kg vs. 247.63 ± 5.72 mg/kg), since a p-value of 0.205 was obtained (Table 6).

There was also sufficient variability in the content of trace elements. Honeys from the coastal area were characterized by significantly higher contents of Fe (16.87 ± 0.41 mg/kg vs. 13.87 ± 0.57 mg/kg), Cu (3.13 ± 0.11 mg/kg vs. 2.21 ± 0.10 mg/kg), and Mn (4.67 ± 0.15 mg/kg vs. 2.63 ± 0.08 mg/kg), with p-values of 0.000, 0.002, and 0.000, respectively (Table 6). Conversely, honeys from the non-coastal area had significant differences in the concentration of Cr (0.23 ± 0.02 mg/kg vs. 0.09 ± 0.01 mg/kg, p-value: 0.000) and Ti (0.43 ± 0.03 mg/kg vs. 0.33 ± 0.03 mg/kg, p-value: 0.041).

Considering potentially toxic elements, honeys from the non-coastal area differed significantly from the coastal counterpart in having higher concentrations of Cd (0.26 ± 0.02 mg/kg vs. 0.17 ± 0.02 mg/kg, p-value: 0.000), Ni (0.35 ± 0.03 mg/kg vs. 0.18 ± 0.02 mg/kg, p-value: 0.000), and Pb (0.41 ± 0.03 mg/kg vs. 0.23 ± 0.01 mg/kg, p-value: 0.000) (Table 6).

3.3. Comparison of Inorganic Elements in Honeys in Relation to the Botanical Origin

Table 7. Content of inorganic elements (mg/kg) in honey samples based on their botanical origin. Results are expressed as mean ± standard deviation of Citrus (n = 15 samples), nasturtium (n = 6 samples), other monofloral honeys (n = 54 samples), and polyfloral honeys (n = 33 samples).

Element	Monofloral Honeys			Polyfloral Honeys (n = 33)	p-Value
	Citrus (n = 15)	Nasturtium (n = 6)	Others (n = 54)
Ca	297.57 ± 9.41 a	239.51 ± 3.32 b	295.43 ± 4.92 a	257.79 ± 5.65 a,b	0.184
Cd	0.36 ± 0.04 a	0.03 ± 0.00 c,b	0.08 ± 0.01 b,c	0.36 ± 0.04 a	0.271
Co	0.18 ± 0.02 a	0.24 ± 0.01 a	0.05 ± 0.01 b	0.36 ± 0.04 a	0.132
Cr	0.14 ± 0.02 a	0.14 ± 0.02 a	0.08 ± 0.01 c	0.28 ± 0.03 b	0.007
Cu	3.84 ± 0.15 a	1.09 ± 0.06 d	2.53 ± 0.09 c,b	2.57 ± 0.07 b,c	0.004
Fe	15.17 ± 0.19 a	9.50 ± 0.23 b	13.90 ± 0.25 a	17.38 ± 0.94 a	0.046
K	863.60 ± 9.39 a	1068.52 ± 15.74 a,b	694.88 ± 5.76 c	3489.42 ± 55.27 b,a	0.000
Mg	106.38 ± 3.14 a,b	78.96 ± 8.58 a	114.43 ± 4.14 a,b	78.33 ± 4.02 a	0.019
Mn	3.78 ± 0.09 a	2.12 ± 0.04 a	4.31 ± 0.19 a	2.97 ± 0.09 a	0.117
Na	155.13 ± 6.55 a	61.33 ± 2.34 c	94.25 ± 3.47 b	254.66 ± 9.93 a	0.000
Ni	0.25 ± 0.03 a	0.28 ± 0.03 a	0.21 ± 0.03 a	0.39 ± 0.03 b	0.001
Pb	0.47 ± 0.02 a	0.14 ± 0.02 a	0.19 ± 0.02 a	0.40 ± 0.03 a	0.083
Se	0.27 ± 0.03 a	0.29 ± 0.03 a	0.20 ± 0.02 b	0.33 ± 0.02 a	0.007
Sn	0.14 ± 0.02 a	0.04 ± 0.01 a	0.08 ± 0.02 a	0.11 ± 0.02 a	0.051
Ti	0.45 ± 0.03 a	0.13 ± 0.01 c	0.25 ± 0.03 b	0.78 ± 0.04 a	0.000
Zn	9.67 ± 0.25 a	2.86 ± 0.10 d,b,c	5.40 ± 0.24 c,b,d	4.82 ± 0.19 b,c,d	0.111

^a–d: Different superscript letters in the same row indicate significantly different values (p ≤ 0.05 by Mann–Whitney U-test); same superscript letters in the same column indicate non-significantly different values (p > 0.05 by Mann–Whitney U-test). Citrus honey samples: HS-5 (13–15), HS-18 (52–54), HS-27 (79–81), HS-29 (85–87), and HS-35 (103–105); nasturtium honey samples: HS-8(22–24) and HS-12 (34–36); other monofloral honey samples: HS1 (1–3), HS-2 (4–6), HS-4 (10–12), HS-6 (16–18), HS-9 (25–27), HS-10 (28–30), HS-11 (31–33), HS-13 (37–39), HS-14 (40–42), HS-15 (43–45), HS-19 (55–57), HS-20 (58–60) and H-21 (61–63) and HS-33 (97–99). Polyfloral honey samples: HS-3 (7–9), HS-7 (19–21), HS-16 (46–48), HS-17 (49–51), HS-22 (64–66), HS-23 (67–69), HS-26 (76–78), HS-28 (82–84), HS-33 (97–99), HS34 (100–102) and HS-36 (106–108).

reports the content of elements in honey samples classified according to the floral sources. Also in this case, inorganic elements such as Li, Mo, Be, Sb, As, and Hg are not included in the table.

The classification was carried out based on their botanical origin. For this reason, all monofloral honeys (n = 75) were subdivided into three groups, named “citrus” (n = 15 honeys), “nasturtium” (n = 6 honeys), and “others” (n = 54 honeys). The remaining honeys were grouped as polyfloral (i.e., bifloral and multifloral) honeys (n = 33 honeys)

Significant variability in the content of certain elements was observed depending on the botanical origin of the analyzed honey.

Among the macro-elements, significant differences were observed for K, Na, and Mg (p-values: 0.000, 0.000, and 0.019, respectively). The highest average content of K was found in polyfloral honeys (3489.42 ± 55.27 mg/kg), followed by nasturtium (1068.52 ± 15.74 mg/kg) and citrus (863.60 ± 9.39 mg/kg) honeys. Similarly to K, the highest Na level was found in the polyfloral group (254.66 ± 9.93 mg/kg). Mg had its highest concentration in the group of other monofloral honeys (114.43 ± 4.14 mg/kg), while the polyfloral group showed the lowest level (78.33 ± 4.02 mg/kg) (Table 7).

Significant differences were observed for trace elements such as Cr, Cu, Fe, Se, and Ti (p-values: 0.007, 0.004, 0.046, 0.007, and 0.000, respectively). On average, the polyfloral honey group had the highest content of Cr (0.28 ± 0.03 mg/kg), Fe (17.38 ± 0.94 mg/kg), Se (0.33 ± 0.02 mg/kg), and Ti (0.78 ± 0.04 mg/kg). However, the citrus honey group had the highest concentration of Cu (3.84 ± 0.15 mg/kg) (Table 7).

Considering potentially toxic elements, only Ni showed significant differences (p-value: 0.001), since polyfloral honeys were characterized by the highest content of this metal (0.39 ± 0.03 mg/kg) with respect to other groups (range: 0.21–0.28 mg/kg) (Table 7).

3.4. Statistical Analysis

As previously mentioned, the PCA was performed to explore the degree of differentiation of n = 108 honey samples based on their element profile and according to their geographical and botanical origin. In fact, it is well known that PCA falls within those exploratory methods that enable data reduction with a minimum loss of original information and exploit plots or graphs just to pinpoint similarities, differences, clusters, and/or correlations among samples and/or variables. These techniques are described as “unsupervised”, as they do not require any input (i.e., prior knowledge of sample provenance, group, or labeling) other than the data set itself [46]. Consequently, PCA should not be considered as a definitive proof of the geographical or botanical origin of the investigated honeys, but rather as a tool to visually highlight the differences in inorganic elements in these matrices, based on their geographical and botanical origin.

3.4.1. Geographical Origin

As already proved by the statistical analysis shown in Table 6, significant differences were found between coastal and non-coastal honeys in relation to eleven inorganic elements, i.e., Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Ti. Hence, a PCA was subsequently carried out with a data matrix encompassing the experimental data obtained from n = 108 samples with respect to the n = 11 variables. The adequacy of data for PCA was proved both by Bartlett’s test, which, with a p-value equal to 0.000, confirmed a patterned relationship among the variables, and the Kaiser–Meyer–Olkin (KMO) that reported a score of 0.703.

According to the Kaiser criterion, three PCs with eigenvalues > 1 were extracted: 4.474, 3.022, and 1.309. These explained up to 80.06% of the total variance (40.68%, 27.48%, and 11.90%, respectively). The bidimensional score plot and the loading plot of the PCA are presented in Figure 2. Although a clear distinction was observed between samples from coastal and non-coastal areas, honeys from non-coastal areas did not show a well-clustered distribution, being present in all quadrants. In fact, the botanical origin of these honeys was also an important factor in differentiation.

However, by superimposing the score and loading plots, non-coastal honeys in the third quadrant had a lower content of Mn, Cu, and Fe than coastal products. In fact, the latter were almost entirely located in the fourth quadrant and characterized by a lower Cd, Cr, K, Ni, and Pb content (Figure 2a). In general, the imperfect discrimination of all the honey samples analyzed, especially those from non-coastal areas, confirmed that the various inorganic elements can vary significantly according to the site of origin of the product.

3.4.2. Botanical Origin

Another PCA was also carried out to classify the honeys under study (n = 108 samples) according to their botanical origin, as already discussed in Section 3.3 and shown in Table 7.

As already highlighted by the statistical analysis conducted in Table 7, significant differences were found between honeys in relation to nine elements, namely Cr, Cu, Fe, K, Mg, Na, Ni, Se, and Ti. Hence, a PCA was run with the data matrix constituted by n = 108 honey samples and n = 9 variables. Bartlett’s test of sphericity obtained a significant p-value (p = 0.000), and the KMO score was equal to 0.634. Two principal components (PCs) with eigenvalues >1 (3.449 and 3.042, respectively) were extracted. These explained up to 72.13% of the total variance (38.33% and 33.80%). The bidimensional score plot and the loading plot obtained from the PCA are illustrated in Figure 3. By superimposing the two graphs, it was clear that the group of other monofloral honeys was best discriminated, with almost all its samples located in the third quadrant and characterized by the lowest content of K, Se, Cr, and Ni. Considering the citrus group, many honeys were found in the fourth quadrant and, consequently, had the highest Cu concentrations. On the other hand, the samples from the nasturtium group were characterized by a lower content of Cu, Fe, and Ti. Finally, the polyfloral group experienced the weakest discrimination, with their samples located in the first, second, and fourth quadrants, as well as at the center of the graph.

3.5. Toxicological Risk Assessment

Given the importance of estimating the safety status of the honeys analyzed, an assessment of the potential toxicological risk to the Algerian and European population following consumption of honeys from coastal and non-coastal areas was conducted by calculating the estimated daily doses (EDIs) of essential elements (

Table 8. Experimental EDIs and RDA% (or AI%) of macro-elements and essential trace elements calculated by considering the consumption of coastal and non-coastal Algerian honeys under study by North African and European populations.

Element	Coastal Honeys				Non-Coastal Honeys
	North African Consumer		European Consumer		North African Consumer		European Consumer
	EDI (mg/d)	% RDA or AI	EDI (mg/d)	% RDA or AI	EDI (mg/d)	% RDA or AI	EDI (mg/d)	% RDA or AI
Ca	8.3 × 10−2	0.01	5.0 × 10−1	0.06	7.5 × 10−2	0.01	4.5 × 10−1	0.06
Cr	2.7 × 10−5	0.07	1.6 × 10−4	0.40	7.0 × 10−5	0.18	4.2 × 10−4	1.05
Cu	9.4 × 10−4	0.09	5.6 × 10−3	0.56	6.6 × 10−4	0.07	4.0 × 10−3	0.40
Fe	5.4 × 10−3	0.04	3.2 × 10−2	0.23	4.5 × 10−3	0.03	2.7 × 10−2	0.19
K	2.2 × 10−1	0.01	1.3 × 100	0.07	8.9 × 10−1	0.05	5.3 × 100	0.27
Mg	3.6 × 10−2	0.01	2.2 × 10−1	0.06	3.0 × 10−2	0.01	1.8 × 10−1	0.05
Mn	1.4 × 10−3	0.07	9.5 × 10−3	0.48	0.8 × 10−3	0.04	3.0 × 10−3	0.15
Na	3.9 × 10−2	<0.01	2.3 × 10−1	0.01	4.8 × 10−2	<0.01	2.6 × 10−1	0.01
Se	7.4 × 10−5	0.14	4.4 × 10−4	0.80	8.5 × 10−5	0.16	5.1 × 10−4	0.93
Zn	1.7 × 10−3	0.02	1.0 × 10−2	0.10	1.8 × 10−3	0.02	1.0 × 10−2	0.10

EDI: estimated dietary intake; RDA: recommended dietary allowance; AI: adequate intake.

) and potentially toxic elements (

Table 9. Experimental EDIs and TDI% (or TWI%, BMDL01%, PTWI%), and UI% (or PMTDI) of potentially toxic elements calculated by considering the consumption of coastal and non-coastal Algerian honeys under study by North African and European populations.

Element	Coastal Honeys				Non-Coastal Honeys
	North African Consumer		European Consumer		North African Consumer		European Consumer
	EDI (μg/kgb.w./d)	% TDI or TWI or BMDL01 or PTWI or UI	EDI (μg/kgb.w./d)	% TDI or TWI or BMDL01 or PTWI or UI	EDI (μg/kgb.w./d)	% TDI or TWI or BMDL01 or PTWI or UI	EDI (μg/kgb.w./d)	% TDI or TWI or BMDL01 or PTWI or UI
As	1.9 × 10−4	0.06	1.1 × 10−3	0.37	1.9 × 10−4	0.06	1.1 × 10−3	0.37
Cd	7.2 × 10−4	0.20	4.3 × 10−3	1.20	1.1 × 10−3	0.31	6.6 × 10−3	1.85
Co	4.5 × 10−4	0.20	2.7 × 10−3	1.18	1.9 × 10−3	0.83	1.1 × 10−2	4.81
Cu	1.3 × 10−2	<0.01	8.0 × 10−2	0.02	9.5 × 10−3	<0.01	5.7 × 10−2	0.01
Hg	1.9 × 10−4	0.03	1.1 × 10−3	0.19	8.6 × 10−5	0.02	5.1 × 10−4	0.09
Mn	2.0 × 10−2	0.01	1.2 × 10−1	0.03	1.1 × 10−2	0.01	6.8 × 10−2	0.02
Ni	8.0 × 10−4	<0.01	4.8 × 10−3	0.02	1.5 × 10−3	0.01	9.0 × 10−3	0.04
Pb	9.6 × 10−4	0.19	5.8 × 10−3	1.16	1.8 × 10−3	0.36	1.5 × 10−3	0.30

EDI: estimated daily intake; TDI: tolerable dietary intake; TWI: tolerable weekly intake; BMDL01: benchmark dose lower confidence limit 01; PTWI: provisional tolerable weekly intake; UI: tolerable upper intake level.

).

For essential elements, the EDI was obtained by considering the amount of honey consumed in North Africa and Europe, which is 0.3 and 1.8 g/day, respectively, based on FAOSTAT data [30], and then comparing it with dietary reference values. For potentially toxic elements, international safety reference values were used for comparison, considering the daily honey consumption of a 70 kg adult.

Concerning the HQ assessed for the non-carcinogenic risk, values always below 1 were obtained by considering the ingestion of inorganic elements, such as As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn, through Algerian honeys by adult consumers both from North Africa and Europe.

4. Discussions

Main findings from this study confirmed that (i) the variability of the inorganic element profile in honey was closely related to its geographical and botanical origin [47] and (ii) many Algerian honeys exceeded the maximum limits fixed for some elements, as indicated by the Codex Standard for honey 12-1981, Rev.2, and the EU Commission Regulation 915/2023. Specifically, this study refers to the current limits of 25 mg/kg for Mg, 15 mg/kg for Fe, 5 mg/kg for Cu and Zn, 0.05 mg/kg for Cd, and 0.01–0.5 mg/kg for As in honey set by Codex Alimentarius, and to the maximum admissible content of 0.10 mg/kg for Pb in honey fixed by the EU Commission Regulation 2023/915 [1,25].

Table 5 shows the average content of inorganic elements found in the Algerian honeys analyzed.

The order of abundance of macro-elements (K > Ca > Na > Mg) observed in this study was also in accordance with what has been reported in the literature [48]. In the same way, the higher abundance of K in honeys is consistent with findings reported in other studies [49,50].

In our study, the K content of the samples ranged from 591.31 ± 3.96 mg/kg (coastal Quercus ilex honey, HS-11) to 13,337.56 ± 233.94 mg/kg (multifloral honey from the non-coastal area of Naâma, HS-26) (Table 5). Particularly, the K content of multifloral honey samples was significantly higher than that of multifloral honey from the semi-arid regions of northeastern Algeria (range: 11.58–124.75 mg/kg) [48]. In addition, the K content of our Ziziphus lotus honeys was notably higher than that of honeys of the same botanical origin analyzed in other literature studies [49,51]. With respect to the geographical origin, honeys from non-coastal areas had a significantly higher K content than those from coastal areas (2948.13 ± 49.58 mg/kg vs. 745.42 ± 6.85 mg/kg, p-value: 0.000, Table 6). This result was the opposite of that obtained by Oliveira et al. [52], who found that honeys from the coastal area had a higher K level, probably due to the influence of marine aerosols. In our case, however, the type of soil in which the melliferous plants grew was probably the main factor affecting the K content of the analyzed honeys [53]. Significant differences in the content of macro-elements were also observed in relation to the botanical origin, as demonstrated by the p-value of 0.000 (see Table 7). In this respect, honeys from the polyfloral group had the highest K content (3489.42 ± 55.27 mg/kg), followed by the nasturtium (1068.52 ± 15.74 mg/kg) and citrus (863.60 ± 9.39 mg/kg) groups. Therefore, as already noted in the literature [54], the content of this metal was found to be influenced both by the geographical and botanical origin of the honey.

Another mineral, namely Ca, varied considerably, with the Ziziphus lotus and Tamarixa africana honeys from non-coastal areas showing the highest (HS-30: 435.32 ± 10.76 mg/kg) and the lowest (HS-31: 83.46 ± 1.59 mg/kg) levels of this metal, respectively (Table 5). These levels were higher than those obtained in other studies related to Algerian honeys. For instance, Nakib et al. [55] found a Ca concentration ranging from 49.0 to 112.0 mg/kg in different types of honey from various regions of Algeria. The same variability was found in a study by Bereksi-Reguig et al. [56] on honeys from western Algeria, which reported Ca concentrations ranging from 33.10 to 502.00 mg/kg. Considering the geographical origin, coastal honeys had slightly higher Ca content than the non-coastal ones (275.45 ± 5.20 mg/kg vs. 247.63 ± 5.72 mg/kg, Table 6). The Ca concentration of our coastal honeys was higher than that reported by Tariba Lovaković et al. [57], who reported an average Ca level of 126 ± 18 mg/kg in strawberry tree honeys from the Croatian coastal area.

According to the literature, the different botanical origins of the product and soil chemistry may play a primary role in determining the calcium levels [17]. However, our study pointed out no significant differences in Ca content according to botanical origin, as indicated by the p-value of 0.184 (Table 7).

Significant variability was also observed in Na levels, ranging from 45.37 ± 3.82 mg/kg to 861.90 ± 35.31 mg/kg, respectively, in bifloral (HS-3) and multifloral (HS-26) honeys from non-coastal areas (Table 5). The Na concentration in almost all the analyzed honeys was lower than that reported by Di Bella et al. [58] in honeys from different areas of northern Algeria (range: 690 ± 40–2030 ± 80 mg/kg), but higher than that reported by Bora et al. [59] in honeys from various regions of Romania (average concentration: 20.76 ± 17.20 mg/kg). This evidence demonstrated that the content of this element can be influenced both by the product’s botanical and geographical origin [3]. With respect to the sample provenance, honey from the non-coastal area had an Na content that was slightly higher than that of the coastal ones (146.86 ± 5.29 mg/kg vs. 129.67 ± 3.74 mg/kg, p-value: 0.000, Table 6). This result could be in contrast with the evidence that coastal honeys may have a high Na content due to their proximity to the sea. However, similarly to K, other factors may also influence the accumulation of Na in plants, and consequently in honey, such as the soil chemistry and the type of irrigation water, fertilizers, and pesticides involved in the agricultural activities [60]. The botanical origin of the honey also had a significant influence on its Na content, as also demonstrated by the p-value of 0.000. In this regard, the highest Na content was found in the polyfloral group (254.66 ± 9.93 mg/kg), followed by the citrus group (155.13 ± 6.55 mg/kg), the group of other monofloral honeys (94.25 ± 3.47 mg/kg), and the nasturtium group (61.33 ± 2.34 mg/kg) (Table 7).

The Codex Alimentarius sets a maximum limit of 25 mg/kg for Mg in honey. Consequently, almost all honeys analyzed in this study exceeded this value, except for the Silybum marianum honey from non-coastal areas. In fact, the concentration range of Mg spanned from 24.25 ± 1.87 mg/kg for the non-coastal Silybum marianum honey (HS-20) to 201.20 ± 5.24 mg/kg for a coastal Citrus sinensis honey (HS-27). The relevant level of this metal in honey could be related to the significant presence of Mg in Algerian soils or the contamination of hives located near industrial areas [3,61] and was already confirmed in previous studies. For example, Di Bella et al. [58] found that the Mg ranged from 690 ± 30 to 1560 ± 50 mg/kg in Algerian honeys. Elevated levels of Mg (range: 69.10–162.00 mg/kg) were also determined by Bereksi-Reguig et al. in honeys from the Tlemcen province in northwestern Algeria [62]. Since the Mg content of honeys produced in coastal and non-coastal areas (120.37 ± 5.39 vs. 99.84 ± 3.34 mg/kg, p-value: 0.000, Table 6) and with different botanical origins (group of other monofloral honeys: 114.43 ± 4.14 mg/kg > group of citrus honeys: 106.38 ± 3.14 mg/kg > group of nasturtium honeys: 78.96 ± 8.58 mg/kg > polyfloral honeys 78.33 ± 4.02 mg/kg, p-value: 0.019, Table 7) varied significantly, it may be assumed that both geographical and botanical origin of honey may affect the concentration of this mineral.

In terms of trace elements, Fe, Zn, Cu, and Mn were found at the highest concentrations in iron in Algerian honeys. Specifically, the abundance order was Fe > Zn > Mn > Cu. However, quantifiable concentrations of Cr, Se, Ti, and Co were also found in almost all the honeys. In contrast, Li, Mo, and Be showed concentrations below the limit of quantification in all samples (Table 5).

The highest Fe content was observed in the non-coastal Euphorbia officinarum honey (HS-19: 42.04 ± 1.67 mg/kg), while the lowest level was in the non-coastal Helianthus annuus honey (HS-9: 5.15 ± 0.14 mg/kg) (Table 5). Overall, 15 of the 36 varieties of analyzed honey samples exceeded the maximum limit for Fe of 15 mg/kg reported by Codex Alimentarius. This variability in Fe content may be due to several factors. Certainly, the geographical and botanical origin of the product plays a crucial role in influencing the accumulation of this element [3]. Not surprisingly, Algeria has several iron mines in its territory, which characterize its soil as having high amounts of Fe [63,64]. However, also the materials used during honey extraction and conservation (e.g., inappropriate container use) can highly influence the final Fe concentration [3,61]. This variability in Fe content was also noted by Mehdi et al. [61], who found Fe concentrations ranging from 0.221 to 60.535 mg/kg in honeys produced in northern Algeria. Our Eucalyptus globulus honey from the Annaba area (HS-10) had an Fe content of 16.74 ± 1.02 mg/kg, which was higher than that observed by Chafik et al. [20] (range: 4.22 ± 0.04 to 8.96 ± 0.12 mg/kg). Furthermore, as can be seen in Table 6, honeys from coastal areas had significantly higher Fe content than those from non-coastal areas (16.87 ± 0.41 vs. 13.87 ± 0.57 mg/kg, p-value: 0.000). These values were generally significantly higher than those obtained by other authors for non-Algerian honeys. For instance, Oliveira et al. [52] could only obtain quantifiable iron values for eight of the eighteen Brazilian and Portuguese honeys analyzed, with an average value of 8.85 ± 15.58 mg/kg. Flamminii et al. [65], on the other hand, obtained non-quantifiable Fe levels for eight honey samples from the Abruzzo region of Italy. Lower Fe contents (4.53 mg/kg) were also found in Slovak honey samples investigated by Sedik et al. [66]. Although less evident than the geographical origin, the botanical origin also significantly influenced the Fe content (p-value: 0.046). In this case, polyfloral honeys had the highest Fe level (17.38 ± 0.94 mg/kg), followed by citrus honeys (15.17 ± 0.19 mg/kg), other monofloral honeys (13.90 ± 0.25 mg/kg), and nasturtium honeys (9.50 ± 0.23 mg/kg).

Variable Zn content was observed, with the non-coastal Tamarix africana honey from Tissemsilt characterized by the lowest concentration (HS-4: 1.05 ± 0.08 mg/kg) and non-coastal Ziziphus lotus honey from Tebessa by the highest levels (HS-30: 17.02 ± 0.12 mg/kg) of this metal. Overall, 13 out of 36 samples had a Zn content above the maximum limit of 5 mg/kg reported by Codex Alimentarius for honey. This result may be due to the proximity of the honey production area to various zinc deposits in Algeria [67]. In addition, other studies have also found Zn levels above the Codex Alimentarius limit. For instance, Derrar et al. [3] reported Zn levels ranging from 6.88 ± 0.20 to 16.90 ± 2.60 mg/kg. By contrast, Di Bella et al. [58] demonstrated that only the multiflora honey from Bouira (5.61 ± 0.40 mg/kg) exceeded the Codex Alimentarius reference value. This was not the case for honey from Algiers, Laghouat, Ghardaia, El Bayadh, M’Sila, Tlemcen, or Naama, for which the range was 2.09 ± 0.12 to 4.67 ± 0.16 mg/kg. In terms of the division between samples from coastal and non-coastal areas, the former were found to have a slightly lower Zn content (5.62 ± 0.17 mg/kg vs. 6.01 ± 0.20 mg/kg). Sager et al. [68] also observed a slightly higher Zn content in samples produced in mountainous areas than in coastal areas (1.27 mg/kg vs. 1.19 mg/kg, p-value: 0.076) in their study concerning the determination of the elemental composition of honey produced in Greece. As already mentioned, in this study, the highest Zn content was revealed in the jujube honey from Tebessa (HS-30). However, according to Bouhlali et al. [69] and Abeslami et al. [70], who determined the content of inorganic elements in Moroccan honeys, this type of honey did not show the highest Zn concentrations. Hence, the geographical variable of the product probably has a more significant impact than the floral source. In fact, in this study, honey samples did not show significant differences in Zn content in relation to the botanical origin, as indicated by the p-value: 0.111 (Table 7).

Concerning Cu, it was found at significant concentrations in all honey samples. The highest Cu content was found in the coastal Eucalyptus gomphocephala honey (HS-33: 6.06 ± 0.41 mg/kg), and the lowest one in the non-coastal Euphorbia officinarum honey (HS-6: 0.51 ± 0.05 mg/kg) (Table 5). Assuming that the Codex Alimentarius establishes a maximum permitted level of 5 mg/kg for Cu, diverse honey samples (i.e., HS-23, HS-24, HS-29, HS-31, HS-33, and HS-35) exceed this level. The average Cu content in the Algerian honeys under study was higher than that reported by Derrar et al. [3] and Di Bella et al. [58] and was significantly higher than the content of 2.57 mg/kg vs. 0.37 mg/kg revealed in multifloral honeys from different Croatian regions by Bilandzic et al. [71]. Furthermore, significant differences in Cu content were observed in relation to both geographical origin (p-value: 0.002) and floral source (p-value: 0.004). For the former, honeys from the coastal area had a higher content than those from the non-coastal area (3.13 ± 0.11 mg/kg vs. 2.21 ± 0.10 mg/kg, Table 6). In terms of botanical origin, however, the highest Cu content was found in citrus honeys (3.84 ± 0.15 mg/kg), followed by polyfloral honeys (2.57 ± 0.07 mg/kg), other monofloral honeys (2.53 ± 0.09 mg/kg), and nasturtium honeys (1.09 ± 0.06 mg/kg) (Table 7).

Significant Mn levels were also determined in Algerian honeys, with a concentration range of 0.05 ± 0.01–8.94 ± 0.15 mg/kg. The lowest content was reported in the multifloral honey from the non-coastal area of Tiaret (HS-28), and the highest one in the Tamarix africana honey from the non-coastal area of Mascara (HS-31) (Table 5). The average Mn values in the honeys analyzed in this study were much higher than those reported by Derrar et al. [3], which were always below 1 mg/kg. However, they were comparable to those shown by Di Bella et al. [58]. Similar average values were also observed in the investigation of inorganic elements in honeys from Kosovo (average Mn value: 2.4 mg/kg) conducted by Kastrati et al. [72]. However, Alemu et al. reported lower Mn levels in Ethiopian honeys than those described in this study [73]. Overall, this scientific evidence demonstrated that geographical origin could also affect the content of this element in honey. As expected, our study revealed significant variations in Mn content between honeys from coastal and non-coastal regions, as indicated by a p-value of 0.000 (Table 6). However, the division of honeys into groups with different botanical origins did not lead to significant differences, as can be seen from the p-value of 0.117 reported in Table 7.

The content of Cr, Se, Ti, and Co was quantified in almost all honey samples (Table 5). However, the concentrations of these elements were almost always below 1 mg/kg, with a few exceptions. With respect to Cr, the lowest value was found in citrus honeys from the coastal Mostaganem area (HS-29 and HS-35: 0.04 ± 0.01 mg/kg). In contrast, the highest Cr value was found in the Euphorbia officinarum honey from the non-coastal site of El Bayadh (HS-19: 0.95 ± 0.03 mg/kg). The Cr levels in Algerian honeys from this study were higher than the Cr content of 0.04 mg/kg reported by Bereksi-Reguig et al. for other Algerian honeys [56]. The geographical origin of the product generally affects the Cr concentration. In fact, significant differences in Cr content were observed between coastal and non-coastal honeys (p-value: 0.000; see Table 6). This evidence also emerges in the literature. For instance, Adugna et al. [74] found significant variability in the Cr content of Ethiopian honeys, ranging from <LOQ to 6.66 ± 0.44 mg/kg. Similarly, Tlak Gajger et al. [75] found that Croatian honeys had Cr almost always above 1 mg/kg.

Significant differences in the content of this metal were also observed in relation to the botanical origin of our honey groups (p-value = 0.007; see Table 7).

For Se, our concentrations ranged from 0.11 ± 0.02 mg/kg in the non-coastal Pinus halepensis–Quercus ilex honey (HS-22) to 0.62 ± 0.04 mg/kg in the multiflora honey from the non-coastal city of Chlef (HS-26). These results were comparable to those reported by Di Bella et al. in other Algerian honey [58], who found a range of 0.38–0.60 mg/kg for this element. However, our study highlighted that significantly different Se amounts were observed only in relation to the botanical species of honey (p-value: 0.007). In fact, polyfloral honeys had a higher Se content (0.33 ± 0.02 mg/kg) than nasturtium (0.29 ± 0.03 mg/kg), citrus (0.27 ± 0.03 mg/kg), and other monofloral (0.20 ± 0.02 mg/kg) honeys (Table 7).

Finally, significant differences in Ti concentrations emerged when considering both geographical (p-value: 0.041) and botanical (p-value: 0.000) variables in the analyzed honeys (Table 6 and Table 7). The opposite result was observed for Co, for which neither variable allowed significant differences to be identified, as indicated by the p-values (Table 6 and Table 7).

Regarding potentially toxic elements, the most abundant were Pb, Cd, and Ni. The levels of As, Sb, and Hg were below <LOQ in almost all samples.

Considerable variability in Pb concentrations was observed, with the lowest and highest values shown by the Tamarix africana honey from Mascara (HS-31: 0.01 ± 0.01 mg/kg) and the Citrus sinensis honey from Skikda (HS-27: 0.98 ± 0.03 mg/kg), respectively (Table 5). This variability is mainly related to the different geographical origins of products, as indicated by the p-value (0.000) reported in Table 6. By comparing the experimental data with the maximum limit of 0.10 mg/kg allowed by EU Commission Regulation 2023/915 [25], more than half of the honeys analyzed exceed the fixed threshold. As already pointed out by Derrar et al., this result could be related to air pollution caused by industry and exhaust gases in these Algerian regions, which consequently damages the environment and products from nearby apiaries [3]. Other literature studies have already observed high mean Pb values in Algerian honeys [58]. Chebli et al. [76] determined the content of toxic elements in honeys from northern Algeria. They reported average Pb values of 0.75 ± 0.16 mg/kg for honeys from the Skikda area, which are slightly lower than values from this study but still higher than the fixed EU limits. Also, Algerian honeys under study were more contaminated than Romanian honeys [77], where Pb was <LOD. This shows how different geographical areas primarily affect the level of contamination in honey.

The geographical origin of the honeys also significantly influenced their Cd content, as can be seen from the low p-value (0.000, Table 6). Cd content overall ranged from <LOQ in samples from the coastal Mostaganem area (i.e., HS-23, HS-29, HS-33, HS-34, and HS-35) and from the non-coastal Mascara city (HS-31) to 1.18 ± 0.10 mg/kg in the multifloral honey from Tiaret (HS-28) (Table 5). Consequently, half of the analyzed samples exceeded the 0.05 mg/kg limit reported by the Codex Alimentarius. The presence of Cd may be due to several factors. Cd is mainly found in the environment because it is used in various industrial processes and in the production of fertilizers, or because it is present in mines [78]. Besides the type of contamination source, other factors such as soil chemistry and altitude can affect its availability [79]. Another study of honeys from certain Algerian regions revealed a lower variability in Cd content, ranging from <LOD to 0.15 mg/kg [80]. By contrast, Gajek et al. [81] showed a Cd variability in Polish honeys similar to that of our findings, with levels ranging from <LOD to 1.121 mg/kg.

There were significant differences in Ni content with respect to both botanical origin (p-value: 0.001) and geographical origin (p-value: 0.000) (Table 6 and Table 7). At present, there is no regulatory limit for this element. In general, the concentration of Ni was quantified in all honeys, ranging from 0.09 ± 0.03 mg/kg in the coastal Erica arborea–Lavandula stoechas honey (HS-32) to 0.53 ± 0.04 mg/kg in the non-coastal Euphorbia officinarum honey from El Bayadh (HS-19). These values were comparable to those obtained by Mehdi et al. (0.19 ± 0.17 mg/kg) [61] and Yaiche Achour and Khali (0.32 mg/kg) [82]. In contrast, our data were higher than those reported by Sana et al. [83] for Pakistani honeys, where Ni was consistently below 0.01 mg/kg. The high levels of Ni observed in our study could be attributed to the anthropogenic environmental pollution, such as car exhaust fumes or smoke emitted by steelworks [84]. Indeed, there are several steelworks in Algeria, including the one in Bethioua.

As previously mentioned, most analyzed samples showed an Hg content <LOQ, except for samples HS-10, HS-13, HS-25, and HS-27, which had Hg at the concentrations of 0.04 ± 0.01 mg/kg, 0.05 ± 0.01 mg/kg, 0.02 ± 0.01 mg/kg, and 0.04 ± 0.01 mg/kg, respectively (Table 5). The low Hg contamination of honey is consistent with the evidence of previous studies involving both Algerian and samples from other countries. For instance, Junior et al. [85] measured Hg in the range of 0.29 ± 0.11–6.71 ± 0.88 μg/kg in different Brazilian honeys.

The average exposure level to investigated elements (Table 8 and Table 9) following the regular consumption of Algerian honey was low in relation to the reference value. This was probably due to the small quantities of honey consumed in North African and European diets (0.3 and 1.8 g/capita/day, respectively). More importantly, the experimental EDIs derived from this study were well below the intake levels of the regulated inorganic contaminants (Table 9). This indicates that the Algerian honey can be safely consumed in the amounts specified in the diet. However, the continuous monitoring of the inorganic element profile in food is paramount to protecting consumer health.

The HQ for the non-carcinogenic risk assessment was below 1 for all the contaminants that could be ingested through honey by adults in North African and European diets. This shows that the health effects from consuming these Algerian honeys are not significant.

However, although the HQ value was always less than 1, indicating a low risk to the population, continuous monitoring of these matrices is necessary, since some of the analyzed honeys clearly showed certain element levels that exceeded regulatory limits.

5. Limitations of the Study

Although the experimental data are analytically valid and reliable, the absence of contamination source identification, information on climatic variability, and beekeeping practices limits the definitive interpretation of the obtained results. Consequently, future research based on a longer monitoring period, access to meteorological data, and analysis of potential contamination sources is strongly encouraged to provide a broader and more detailed picture of the context in which Algerian honeys are produced.

6. Conclusions

In this study, the element profile of an array of Algerian honeys was assessed. Experimental results pointed out that over half of the Algerian honeys exceeded the current EU limit for Pb of 0.10 mg/kg. Furthermore, many honeys exceeded the international limits fixed by the Codex Alimentarius for Mg, Fe, Zn, Cu, and Cd. However, despite the frequent exceedance of regulatory limits, the average exposure to these elements resulting from consuming Algerian honeys is low and does not pose a health risk to consumers. Hopefully, this study will encourage the Algerian authorities to support the beekeeping sector by launching monitoring programs, strengthening quality control procedures in honey production, and establishing a national regulatory framework for honey quality and safety that aligns with current international and EU standards.