Amir Ismail

Heavy metals in vegetables and respective soils irrigated by canal, municipal waste and tube well waters

Heavy metal contamination in the food chain is of serious concern due to the potential risks involved. The results of this study revealed the presence of maximum concentration of heavy metals in the canal followed by sewerage and tube well water. Similarly, the vegetables and respective soils irrigated with canal water were found to have higher heavy metal contamination followed by sewerage- and tube-well-watered samples. However, the heavy metal content of vegetables under study was below the limits as set by FAO/WHO, except for lead in canal-water-irrigated spinach (0.59 mg kg−1), radish pods (0.44 mg kg−1) and bitter gourd (0.33 mg kg−1). Estimated daily intakes of heavy metals by the consumption of selected vegetables were found to be well below the maximum limits. However, a complete estimation of daily intake requires the inclusion of other dietary and non-dietary exposure sources of heavy metals.

Effect of pomegranate peel supplementation on nutritional, organoleptic and stability properties of cookies

Abstract The present study aims at highlighting the nutritive potential of pomegranate peel and its possible utilization as an ingredient of choice to nutritionally enrich cookies. Biochemical composition and free radical scavenging features of pomegranate peel powder (PoP) and PoP supplemented cookies were measured. PoP supplementation significantly (p < 0.05) improved dietary fibers (0.32–1.96 g/100 g), total phenols (90.7–161.9 mg GAE/100 g) and inorganic residues (0.53–0.76 g/100 g) of cookies. Similarly, significant increase in Ca, K, Fe and Zn levels was noted in supplemented cookies. Almost 50% 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was recorded in cookies carrying highest concentration of PoP and phenolic contents. PoP phenolics of supplemented cookies were shown to reduce oxidative degradation during four months storage. Present study suggests PoP supplementation in baked products as a potential source of micro and macronutrients. Application of PoP in ready to serve foods seems to be a potential disease preventive and ameliorative approach in tandem with its preservation and nutritional enhancement features.

Aflatoxin M1: Prevalence and decontamination strategies in milk and milk products

Abstract Aflatoxin M1 (AFM1) in milk is among the most carcinogenic compounds, relatively high levels being consumed, especially by the most vulnerable age groups, i.e. infants and the elderly. Reports on its prevalence are constantly being received from various parts of the world compelling nations to establish their own standard limits for AFM1. Global review of the literature indicates the existence of methods of partial decontamination of AFM1, however; evidence based studies do not suggest that any single strategy as a coherent and complete solution to the issue. Microbial decontamination of AFM1 has emerged as the most suitable method up to now but the stability of toxin-microbial cell complexes still remains questionable. This review discusses the chemical nature, established maximum permissible limits and prevalence of AFM1 in various countries from 2009 to 2014. Moreover, the possible mechanisms for AFM1 reduction mainly the microbial decontamination and the stability and bioaccessibility of microbial-AFM1 complexes are also discussed.

Estimated daily intake and health risk of heavy metals by consumption of milk

Cd, Co, Pb, Cu and Ni were analysed in 480 milk samples by flame atomic absorption spectrophotometry. Mean concentrations were 0.001, 0.061, 0.014, 0.738 and 0.028 mg/kg, respectively. Mean concentration of Cd was very low, whereas Cu exceeded the maximum limits established by the Codex Alimentarius. In some areas, the Pb concentration exceeded the maximum limit as set by the Codex Alimentarius. The highest estimated daily intake (EDI) of Cu calculated for male infants (1–3 year) was 33.534 µg/kg bw/day, while the lowest EDI was recorded for Cd (0.004 µg/kg bw/day) in adult females above 16 years. The results suggested that Cu and Pb from milk in the investigated areas may pose a health risk to the consumers.

Determination of Aflatoxin M1 and Heavy Metals in Infant Formula Milk Brands Available in Pakistani Markets

Aflatoxin M1 (AFM1) after its bioconversion from aflatoxin B1 in animal liver becomes the part of milk while heavy metals get entry into milk and milk products during handling in the supply chain. Aflatoxin M1 and heavy metals being toxic compounds are needed to be monitored continuously to avoid any ailments among consumers of foods contaminated with such toxicants. Thirteen commercially available infant formula milk (IFM) brands available in Pakistani markets were analyzed for the quantitative determination of AFM1 and heavy metals through ELISA and atomic absorption spectrophotometer, respectively. AFM1 was found positive in 53.84% samples while 30.76% samples were found exceeding the maximum EU limit i.e. 0.025 μg/kg for AFM1 in IFM. Heavy metals lead (Pb) and cadmium (Cd) were found below the detection limits in any of the sample, whereas the concentrations of iron (Fe), zinc (Zn) and nickel (Ni) ranged between 45.40-97.10, 29.72-113.50 and <0.001-50.90 μg/kg, respectively. The concentration of Fe in all the tested brands was found in normal ranges while the concentrations of Zn and Ni were found exceeding the standard norms. Elevated levels of AFM1, Zn and Ni in some of the tested IFM brands indicated that a diet completely based on these IFM brands might pose sever health implications in the most vulnerable community i.e., infants.

Antibiotic Residues in Chicken Meat: Global Prevalence, Threats, and Decontamination Strategies: A Review

Poultry production is among the most rapidly growing industries around the globe, and poultry is one of the major sources of meat. Poultry farmers use disease preventive and growth promoter antibiotics for faster growth of chickens in the shortest possible time to increase the rate of feed assimilation and to lower the incidence of mortality caused by a pathogen attack. Antibiotics may result in dysfunctionality of beneficial gut microbiota and increase resistance among microbial pathogens in poultry. Residues of these antibiotics in poultry meat have been determined in many of the studies globally and are considered one of the possible causes of antibacterial resistance in human pathogens. The presence of residues of antibiotics in poultry meat and meat products beyond maximum permissible limits is a matter of serious concern. Heat treatments can reduce the risk of some sulfonamides, tetracyclines, and fluoroquinolones but do not guarantee the complete elimination or degradation of these antibiotic residues present in broiler meat. Some of the developed countries, including Sweden, Norway, Denmark, and the European Union have already prohibited the application of antibiotics for preventive, as well as growth-promoting purposes. Training farmers to monitor withdrawal periods, banning the use of antibiotics as growth promoters, and adopting the veterinary feed directive of the U.S. Food and Drug Administration are important parameters to mitigate the emergence of antibiotic resistance in bacteria related to poultry production.

Aflatoxin in foodstuffs: Occurrence and recent advances in decontamination

Aflatoxins are highly toxic compounds produced as secondary metabolites by some Aspergillus species, whose occurrence have been reported predominantly in several types of foods of low moisture content, while aflatoxin biotransformation products have been reported mainly in milk and milk products. This review deals with the occurrence of aflatoxins in some of the major food products in the last 5 years including regulatory aspects, and recent advances in detoxification strategies for contaminated foods. Aflatoxin contamination in cereals including corn and peanut is still a public health problem for some populations, especially in African countries. Despite that most of physical and chemical methods for aflatoxin detoxification may affect the nutritional properties of food, or are not safe for human consumption, gamma-radiation and ozone applications have demonstrated great potential for detoxification of aflatoxins in some food matrices. Biological methods based on removal or degradation of aflatoxins by bacterial and yeast have good perspectives, although further studies are needed to clarify the detoxification mechanisms by microorganisms and determine practical aspects of the use of these methods in food products, especially their potential effects on sensory characteristics of foods.

Heavy metals in milk: global prevalence and health risk assessment

Abstract Heavy metal toxicity is linked with a number of diseases but the severity of situation multiplies too many folds if these heavy metals are found in milk, which is the basic food item of vulnerable age group of people. In this review article, the toxic impacts of different heavy metals on human health, their sources in milk, detection methods, and regulatory limits for heavy metals in milk are described. This study also emphasizes the prevalence level of different heavy metals in milk samples from different parts of world reported during the years 2011–2016 and the strategies to control the level of heavy metals in milk below the permissible limits will also be discussed.