Chemical Analysis of Honey – A Biological Assessment of Environmental Pollution in Lebanon Post July 2006 War

13.07.2007

Abstract :

The purpose of this study is to assess the environmental pollution in Lebanon post- July 2006 war, through the chemical analysis of bee honey harvested from different war regions. The amounts of Lead (Pb), Cadmium (Cd) and Phosphorus (P) contained in the samples harvested after the war have been determined using an atomic absorption spectrophotometer (AAS). Amounts of heavy metals above the admitted limits, set by the Codex European Committee, have been detected in all samples. The results suggested a possible correlation between the use of chemical weapons and the presence of toxic elements in the environment.

Introduction

For thirty-four days (July 12- Aug 14, 2006), a very large section of Lebanon was subjected to heavy shelling with different kinds of bombs releasing high levels of chemicals harmful to the environment, and subsequently to human life. News published in local and international media referred to the use of chemical weaponry “that badly polluted the air and environment” (Feghali, 2006). This was confirmed by an Israeli journal (Rappaport, 2006).

Honey has been frequently used for bio-monitoring the distribution and impact of various environmental pollutants, including: trace elements, heavy metals, radionuclides, pesticides and organic pollutants (Bratu & Georgescu, 2005).

Statement of the problem

The purpose of this study is to establish a correlation between the amount of heavy metals found in the samples harvested from the possibly contaminated regions and the sites targeted during the war.

Review of Related Literature

Bio-monitoring is a valuable assessment tool that is receiving increased attention in environment quality monitoring programs. In a general sense, bio-monitoring may be defined as the use of organisms/materials to obtain quantitative information on certain characteristics of the biosphere (Wolterbeek, 2002). The quantitative information may be defined as a measure of integrated exposure of exposed organisms/materials over a certain period of time (Smodiš and Bleise, 2002).

Honey bees are good biological indicators because they indicate the chemical impairment of the environment they live in through two signals: the high mortality (in the case of pesticides) and the residues present in their bodies or in beehive products which may be detected by suitable laboratory analyses (Porrini, 2003).

Almost all environmental sectors (soil, vegetation, water, air) are sampled by honey bees, since an eclectic variety of materials is brought into the hive.

Heavy metals emitted in the atmosphere are not degraded and are continuously kept “in play”; thus entering the physical and biological cycles. These can deposit on the hairy bodies of bees and be brought back to the hive with pollen, or they may be absorbed together with the nectar of the flowers or through the water. A number of variables has to be considered when using honey to monitor heavy metals in the environment: the weather (wind can transfer heavy metals to other environmental sectors), the season (the pollutants could be more diluted in summer and autumn than in spring), and the botanical origin of the honey (Celli, 1994).

As for the use of honey bees and hive products in monitoring radioactivity, it dates back to the end of the 1950s, and has reached its excellent efficacy in the context of the Chernobyl disaster (Tonelli and Gattavecchia, 1990).

Statement of the Hypothesis

It is hypothesised that there is a correlation between the chemical pollution of the environment and the bombings during the July 2006 war in Lebanon. “Chemical pollution” is defined by the amounts and types of heavy metal residues contained in the honey samples harvested in the targeted areas. “Bombing” refers to the use of weapons that release huge amounts of chemical pollutants, contaminating the whole area(s).

Methods

Participants

Bee honey samples harvested after the July 2006 war were collected from five different areas in Lebanon - South Lebanon (3 samples), Bekaa valley (1 sample), and North Lebanon (1 sample). The South, being the main arena of the war, was represented by three samples from three different locations. The two other samples were collected form regions that were less targeted in order to point out the relationship between the concentrations of heavy metals found in honey from the main target area (South), compared with the ones found in less targeted areas (Bekaa and North).

Instrument

The natural honey samples were donated by private beehive keepers from Beyno, Sfaray, Marjeyoun, Hermel and Bazourieh. The honey samples were collected in sterile containers and stored at room temperature. They were labelled from 1 to 5 in the order of the areas mentioned above and sent to the Industrial Research Institute (IRI) for analysis.

The sample analysis followed standard methods for detecting heavy metals approved by the Codex Standards for Honey in Lebanon (Codex, 2001). Atomic absorption spectrophotometry (AAS) was used for heavy metal detection where the amounts of Lead, Cadmium and Phosphorus were measured.

Results

The results of the samples are presented in the tables below. The maximum admitted levels (MAL) of Pb, Cd, and P set by the Codex Alimentarius Stan ( Codex 1994) are shown for comparison (see figures 1, 2 and 3).

Fig. 1: Pb content in honey samples

Fig. 2: Cd content in honey samples

Fig. 3: P content in honey samples

Discussion

As seen in the figures 1, 2 and 3, the levels of Pb, Cd and P are above the (MAL) for all tested honey samples except for sample 1 where the level of Phosphorus was below the MAL. No significant difference in Pb and Cd levels was found among the honey samples collected from the five different areas. Significantly higher levels of P were detected in the Southern samples. This might be due to the fact that the Southern areas of Lebanon were more targeted by Phosphorus munitions in different forms during the war (Rappaport, 2006).

On the other hand, the same high levels of Lead and Cadmium detected in all samples could suggest that these pollutants are scattered throughout the atmosphere by wind and precipitation and do not deposit in one place (Porrini, 2003). As for Phosphorus which is a non-metal, it has a different environmental fate; it is not an air-scattered pollutant but deposits in water and soil. This explains the significantly higher levels of P in samples 3 and 5 where z=0.99 (fig 3).

During and after the war, many reports warned against an environmental catastrophe due to the use of chemical weapons in different forms. “These are chemicals that are bio-accumulative and persistent; so when you inhale them, they stay in your body and they do cause cancer. These chemicals are being banned internationally, and if they are burned that way, the results are disastrous”, says Zeina al-Hajj of Greenpeace (Hmaidan, 2006).

Heavy metals are dangerous because they tend to bioaccumulate. Bioaccumulation is defined as the accumulation of compounds in living things any time they are taken up and stored faster than they are metabolized or excreted. (Palmer, 1991)

Lead intoxication can arise through the regular consumption of foodstuffs only slightly contaminated with lead. Lead is a typical cumulative poison, and the danger of chronic intoxications is the greater problem; these may result in toxic biochemical effects in humans which in turn cause problems in the synthesis of haemoglobin, kidneys, gastrointestinal tract, joints and reproductive system, besides acute or chronic damage to the nervous system. (Abdullah, 1990)

As for Cadmium, which is spread by air and water far over sea and land, especially in the vicinity of heavy industrial plants, it is today regarded as the most serious contaminant of the modern age. It is absorbed by many plants and sea creatures; and because of its toxicity, presents a major problem for foodstuffs. In humans, long-term exposure to Cadmium is associated with renal dysfunction.

Accumulation can lead to obstructive lung disease and has been linked to lung cancer. (Gazza, 1990)

In contrast, Phosphorus is essential for the human body, but can become a deadly poison if the kidneys are not able to excrete the surplus fast enough. Excess dietary Phosphorus raises the acidity of the normal alkaline interior of our cells. This makes them vulnerable to DNA damage which is the base cause of cancer, arthritis and artery disease. (Heilbrun, 1986).

Yet, the real problem lies not in the consumption of contaminated honey, but in other food items that are consumed in higher amounts; especially fruits, vegetables and water.

Limitations

Unfortunately, Lebanon has a poor record of analytical protocols for the contamination of food items with heavy metals, including honey. An analytical study of honey before the war would have served towards a better comparison of results. Other aspects of the research had to be overlooked due to the high cost of analysis. A larger and more representative sample that includes other areas of Lebanon such as Metn and Keserwan and analysis of more elements could have helped in enhancing the validity of the study.

Conclusion

Our results reflect the effect of the 2006 war on the Lebanese environment through the use of honey as a triple-fold indicator for air, soil, and water pollution. They also prove another method of assessing the degree of pollution of the environment at a particular distance from the contaminated source (South Lebanon).

In all analysed honey samples, the presence of heavy metals like Pb and Cd, in addition to P, was detected above the maximum admitted levels.

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