Monitoring of Some Organophosphorus and Organochlorine Pesticides Residue in Beef Meat from Khartoum State Slaughterhouses

Monitoring of Some and in from Abstract Background: Organochlorine and Organophosphorus Pesticides are found in the environment in small concentrations, but they have cumulative characteristics thus become a threat to human health and life. This study is focused on detection and determination of some of these pesticides in bovine muscles, meat in two main slaughterhouses in Khartoum state. Materials and methods: 50 samples were collected in sterile bags, transferred to the lab, samples were extracted within 24 hours of collection using mixture hexane and acetone, followed by partitioning and drying the samples using rotary evaporator at 40ºC. clean up step was achieved using silica gel column previously washed with hexane. Pesticides residues read against standards using GC-FID. Results: seventy-two percentage of samples obtained from slaughterhouse one was positive, while slaughterhouse two showed 87.5% positive samples. Ethiphane is the prevailing pesticide residue in samples obtained from both slaughterhouse facilities, it represented 61.1% and 80.9% respectively. The mean value of the detected levels was 0.147 and 0.27 ppm in order.


Introduction
Food producers must guarantee food supply by increasing production, in order to face the progress of human population development [1]. Agricultural products with its two major sectors (agricultural and animals), are at risk of encountering various debase agents such as insects, fungi, bacteria; these agents may lead to low quality products or even may cause complete loss of these products. Although, the pesticides are broadly used around the whole world since a century ago, but most of them have been debarred; especially organochlorine class affiliates. These compounds have highly toxic influence, tenacity in environment and they are characterized by their potency to accumulate in of human and animal tissues, this could be attributed to their lipophilic nature e.g. (Heptachlor) [2]. Due to the vital impact of these compounds on human health and on the environment as general, the continuous and sustainable follow up through monitor and carry on surveillances is extremely needed [3]. The common obtainability of pesticides makes the tracking of these compounds' residue in environment; particularly in food; an imperative issue [4].
These compounds have the ability to remain without being degraded in the environment, in addition to lipophilic nature and bioaccumulation tendency, all these criteria make them detectable in high concentrations in fatty foods, such as chicken, fish, meat and dairy products. The residual amounts of pesticides lead to tremendous negative effect on human health whom consume those products [5]. In order to lower the risk of consuming such products, efforts should be done to guarantee obligation with maximum residue limits in food commodities which is globally determined [6,7]. One of the pesticides classes, those intricate in toxicity is organophosphorus pesticides. The neurotoxicity caused by this class of pesticides is due to their capability to inhibit the acetylcholinesterase [8]. OPs may also be concentrated in fat. The degradation of the OPs and the formation of primary and secondary metabolites are induced by exposure to high temperature; light; enzymatic systems; microorganisms; and acidic, neutral, and alkaline PHs. However, in beef muscle some OPs and their metabolites could not be completely eliminated after cooking [9].
The present work is carried out to screen the occurrence of organochlorine and organophosphorus pesticides residue in meat obtained from two slaughterhouses. As well, this work is made, to determine the level of the residues and compare it with the maximum residue limits which authorized by the international organizations.

Samples Extraction
Extraction: Meat tissue samples were extracted for O.C and O.P pesticides residue following the procedure described by [10].
Twenty grams of each meat sample, were weighed and placed in a blender with 20 g of sodium sulphate anhydrous and merged in a high speed then 120 ml of n-hexane and 120 ml of acetone were added to the mixed sample, then the sample and the solvents were blended for 15 minutes. Distilled water is used to wash the extract in a separatory funnel. The sample wetness was dried by passing through anhydrous sodium sulphate and the solvents were dispersed at 40 C in a rotary evaporator till complete dryness.
Partitioning: Partitioning of the extracted meat samples was performed according to Leon et al. [11].

Standardization and Validation Studies of Gas Chromatography Technique
The system precision was assessed by reviewing the reproducibility of the instrumental reaction with respect to retention  Table 1).

Statistical analysis
The analysis was carried out using Statistics-10 program designed for Windows. Differences between obtained values were performed by analysis of variance (ANOVA) the LCD test was used for determining the significance level of at least p<0.05.  In consideration to slaughterhouse (1); 33.3 % of samples which contained diazinon residue exceeded the maximum residue limits; which defined by the specialized organizations. As well as,

37.5% of samples contained profenofose. Samples which contained
Ethiphane and Oxyfluorfene, the residue in all samples, was over the allowed levels. The same trend was followed in slaughterhouse (2), all oxyfluorfene and ethiphane residue limits exceeded the permissible levels. Diazinon and profenofos levels; were below the acceptable limits ( Figure 3 & Table 2).

Discussion
The contamination of animal's products, which proposed for human consumption can occur via different approaches. The animal which exposed to pesticides in order to control insects; by dipping or spraying and due to the fat solubility nature of these chemicals, animals have tendency to accumulate and store them in their bodies.
The total withdrawing process of these chemicals from the animal's  they verified chlorpyrifos residue in meat samples, the detected amount was higher than the documented levels in literature [17,18], this result synergize our present findings.

Conclusion
The detected pesticides residue in the present study, may reveal the wide, intensive use of organophosphorus pesticides in Sudan in comparison with organochlorines. Out of 6 detected pesticides 5 were belong to organophosphate class. Ethiphane is the prevailing pesticide residue in samples obtained from both slaughter facilities.
All samples in which Ethiphane and Oxyfluorfene were detected, the residue was over the allowed levels.

Recommendations
The presence of herbicides residue in meat samples in the current study, had demonstrated the transfer of pesticides through linear chain from soil to underground water, plants and consumption by the animals leading to accumulation of residues in their products. The hazard of human consumption of animal products polluted with pesticides residue make it necessary to upraise the awareness of producers and consumers with standard pesticides usage, with stress on committing to withdrawal period of every and each pesticide.