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Abstract The food safety and its quality assurance for consumer become has a major concern. Egypt should establish an integrated regulatory system for food safety through which a national residues surveillance programme should established to monitor the presence of different contaminants in food such as pesticide residues, veterinary drugs including chloramphenicol, sulfonamides, tetracyclines, macrolides, β- Lactam and qunolines , histamine as well as highly toxic elements of heavy metals such as lead, cadmium, copper, mercury and arsenic, to protect the human health from different possible risks in addition to having the probability to export its food to European countries. Egypt as a third country should to submit monitoring plans to the European Commission (EU) for approval every year to be included in the exporting country list. Food of animal origin such as aquaculture fish, honey, poultry are banned for exportation to EU due to lack of national system of inspection of the residues and contaminates. Egypt has no chance to export food to European Commission due to lack of such data needed; including the testing laboratory as well as the national monitoring control plan. The testing of such contaminants should be performed by the official and accredited laboratories. This study aimed to ensure the Egyptian food quality especially fish to be safeguarded to human consumption and so protect them from high risk hazardous and to facilitate the international trade through ensuring the safety and quality of fish from residues of veterinary drugs, histamine and heavy metals, thereby being legally exported to different countries according to international standards and regulations. This was done by developing and optimizing different methods of analysis for veterinary drugs, histamine and metallic contaminants to improve cost-effectiveness and explicabilities and to meet the performance requirements necessary for use as regulatory methods for international trade and consumer protection needs. Veterinary drugs residues and biogenic amines especially histamine and metallic contaminants which contribute large groups of food contaminants, are becoming of great concern in food safety and international trade of food products. Maximum residue limits (MRL’s) for some veterinary drugs and histamine and maximum limits for some metallic contaminants have been established by many organizations, such as the Codex Alimentarius , European Union (EU) and US Food and Drug Administration (FDA) for different types of foods to eliminate the technical barriers and enhance the international trade as well as ensuring that consumers are not exposed to unsafe levels of hazardous materials. Histamine is a biogenic amine generated post-mortem in fish and certain fish-based products due to product mishandling, bad storage and abuse which causes the allergy-like symptoms of scombroid poisoning, estimation of histamine levels in foods is desirable because of its potentially toxic effects and also because it can be used as indicator of food freshness and spoilage during transportation. In the current study rapid, precise, and reliable method for quantification of histamine was developed and optimized to identify and detect histamine in fish and fish products to asses the quality for food safety before exporting to European countries and prevent consumer from health hazards. Method development includes optimization of different analytical method steps; histamine derivatization; extraction with different solvents,study of matrix effect and optimization of HPLC conditions. Different method validation parameters were studied to ensure the fitness for purpose of the analytical method, for example, limit of detection, limit of quantitation, method recovery, linearity, method precision and estimation of measurement uncertainty. The average recovery was 96% with coefficient of variation (CV %) less than 8%. The uncertainty was estimated and was set to 26.4%. The performance of the proposed method was checked with a sample from the Food Analysis Performance Assessment Scheme (FAPAS) as an external quality control; the z- score was found within acceptable range │Z│< 2. Thirty four fish samples and 16 canned tuna samples were subjected to histamine assessment using the validated method. Only one sample was contaminated with histamine and exceeding the permissible limit set by Codex Alimentarious and European Commission. The study also included analysis of veterinary drug residues in aquaculture fish. However, most of the aquaculture systems in the world are based on intensive cultivation methods. These methods are characterized by high stock density and volume, use of antibiotics, antifungal and other pharmaceuticals can cause serious health problems in consumers. In this study, simple and reliable multiresidue method of analysis for determination of veterinary drugs residues in different animal products was developed. In this method different drugs groups, e.g. sulfonamides, tetracyclines, macrolides, β- Lactam , qunolines and unauthorized antibiotics such as chloamphenicol were optimized and determined with good sensitivity using LC/MS/MS and fulfill the Codex and EU regulations. Most of compounds (19 drugs) were analyzed in electrospray ionization positive mode (ESI+) while only chloamphenicol was analyzed in electrospray ionization negative mode (ESI-). Method development includes optimization of different analytical method steps; extraction with different solvents, study of matrix effect and optimization of LC-MSMS conditions. Different method validation parameters were studied to ensure the fitness for purpose of the analytical method, for example, method recovery, linearity, method precision and estimation of decision limit (CCα) and the detection capability (CCβ). In general, the average recovery ranges of the test compounds are acceptable according to the European Commission guidelines 657/2002/EC. However, the limit of quantitations (LOQ) was 25 ug/kg for all tested drugs except for chloramphenicol it was 0.15 ug/kg. The method performance was tested using proficiency test to evaluate the compliance with │Z│ score; where zscore ≤ ±2 indicated acceptance. The developed and validated method was used to monitor the levels of veterinary drugs in fish samples collected from Egyptian local market. Fifty samples of different types of fish samples (Nile Tilapia, Nile Perch, Tilapia gallilly , Tilapia Zillii ) were analyzed using the proposed method for presence of the 20 veterinary drugs under investigation. No residues were found in the tested samples. Further investigations should be done to cover more aquaculture farms as well as more fish types. Heavy metals also addressed in this study as they are a group of environmental contaminate pose hazards to human health. However, heavy metals are discharged into the environment through urban discharge, agriculture, mining, combustion and industrial discharge, and can accumulate to toxic concentrations and cause ecological damage, and subsequently be transferred to humans through the food chain. Mercury, lead, cadmium and arsenic are considered to be the most dangerous metals and have been associated with serious adverse health effects. Copper, although an essential metal, may produce toxic effects such as liver cirrhosis, dermatitis and neurological disorders when consumed in excessive amounts in foods such as fish and fish products. Development of accurate and sensitive method for determination of 11 elements including, lead (Pb), Cadmium (Cd), Arsenic (As), Copper (Cu) and mercury (Hg), zinc (Zn), Aluminum (Al), Iron (Fe), chromium (Cr), Magnesium (Mn), Tin (Sn) using atomic absorption spectrophotometer (AAS) with microwave digestion has been done. The obtained mean recoveries range was 86-104% with CV% of 7-11%. The method performance was also tested using proficiency test to evaluate the compliance with │Z│ score; where z-score ≤ ±2 indicated acceptance for Cd , Hg and Cu. The applicability of the validated method to routine analysis was doneby analysis of 131 fish samples collected from Egyptian local markets during 2009/2010. The validated method was then applied for the detection and determination of heavy metals. The results were reported and assessed based on the maximum tolerance value set by Codex Committee of Food Additives and Contaminants (CCFAC, 1993 amended 2009). Lead, cadmium and mercury were the violated elements with percentages of 3%, 9.9% and 3%, respectively. |