Wajih N. Sawaya

Benzo[a]pyrene and total polycyclic aromatic hydrocarbons (PAHs) levels in vegetable oils and fats do not reflect the occurrence of the eight genotoxic PAHs

Concentrations of polycyclic aromatic hydrocarbons (PAHs) were determined in 115 samples of olive oil (extra virgin olive oil, virgin olive oil, olive oil, pomace olive oil and blended olive oil), cooking oil (corn oil, sunflower oil, sesame oil, palm olein oil, soya oil, canola oil, mustard oil, peanut oil and mixed vegetable oil) and fat (butter and table margarine) collected from retail stores in Kuwait. Carcinogenic benzo[a]pyrene (BaP) was detected in 43% of the samples analyzed. Benz[a]anthracene and chrysene were detected in 37 and 45% of the samples, respectively, that did not contain BaP. Of the individual non-carcinogenic PAHs, naphthalene showed the highest mean concentration (14 µg kg−1), while for the carcinogenic PAHs, BaP (0.92 µg kg−1) and chrysene (0.87 µg kg−1) showed the highest mean values. Approximately 20% of the samples within the olive oil and cooking oil sub-categories exceeded the EU maximum tolerable limit for BaP, with the highest level of 6.77 and 11.1 µg kg−1, respectively. For the fat sub-category, 9% of the samples exceeded the tolerance limit, with the highest level of 3.67 µg kg−1. The Kuwaiti general populations dietary exposure to the genotoxic PAHs (PAH8: benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenz[a,h]anthracene and benzo[ghi]perylene) was estimated to be 196 ng day−1 (3.3 ng kg−1 bw day−1, assuming an average adult body weight of 60 kg). Results indicated that PAH8 and BaPeq (total sum benzo[a]pyrene equivalents) are more reliable measures of the concentrations of other carcinogenic PAHs in oil and fat samples, while BaP and PAHs alone are not good indicators of the occurrence or degree of contamination by carcinogenic PAHs in these food products.

Estimates of dietary exposure of children to artificial food colours in Kuwait.

To assess the intake of artificial food colour additives by 5–14-year-old children in the State of Kuwait, a 24-h dietary recall was conducted twice on 3141 male and female Kuwaiti and non-Kuwaiti children from 58 schools. The determination of colour additives in 344 foods items consumed was performed using high-performance liquid chromatography with diode array detector. A comparison with the Food and Agriculture Organization and World Health Organization acceptable daily intakes (ADIs) was undertaken to evaluate the potential risk associated with the consumption of artificial colour additives by children in Kuwait. The results indicated that out of nine permitted colours, four exceeded their ADIs by factors of 2–8: tartrazine, sunset yellow, carmoisine and allura red. Further, follow-up studies to provide insight into potential adverse health effects associated with the high intakes of these artificial colour additives on the test population are warranted.

Dietary intake of organophosphate pesticides in Kuwait

Abstract The State of Kuwait, in cooperation with the U.S. FDA, conducted a total diet study (TDS) to estimate pesticide intake by the population. The organophosphate (OP) pesticide levels in 139 food items, constituting the TDS core list, are reported here. The TDS core food list was established through a nationwide food consumption survey. All foods were prepared as eaten, and analyzed for their organochlorine pesticide, OP, carbamate, benzimidazole and phenyl urea contents. The FDAs Multiresidue Methods, PAM I, were used employing GC, HPLC and GPC. Twenty-five of the foods analyzed contained OPs. These included 7 of 12 cereal products (chloropyriphos=0.03–0.21 ppm and fenetrothion=0.016–0.84 ppm), 6 of 16 vegetables (diazinon=0.05–0.2 ppm, and chloropyrifos, and fenthione sulfone), 1 of 16 fruits (monocrotophos) and 11 of 47 composite dishes (chloropyrifos methyl=0.011–0.089 ppm and fenetrothion 0.011–0.044 ppm). The higher levels of fenetrothion in one cereal product exceeded the MRLs, and warrant corrective and preventive measures. The daily intakes of OP pesticide residues are discussed in light of the ADIs of the FAO/WHO (1993). Codex Alimentarius. Pesticide residues in food (Vol. 2, 2nd ed.). Rome: Joint FAO/WHO Food Standards Programme.

Chemical composition and nutritional quality of tehineh (sesame butter)

The chemical composition and nutritional quality of tehineh, a paste of dehulled roasted sesame seeds, from Saudi Arabia and other countries, were studied. Results showed 24.7% protein, 58.9% fat, 2.3% fiber, 3.0% ash and <1.0% moisture. The tehineh contained relatively high amounts (mg/100 g) of P (692), Mg (362), Fe (7.19), Cu (1.96), Mn (1.46) and Zn (7.82) and low amounts of Ca (61) and Se (0.05). Gas-liquid chromatography (GLC) analysis of the oil revealed percentages of 42.4 for oleic, 39.7 for linoleic, 9.8 for palmitic and 6.4 for stearic acid. Lysine was the only limiting amino acid with a chemical score of 64, while the sulphur-containing amino acids (methionine + cystine) and tryptophan were present in amounts exceeding the requirement of the FAO/WHO (1973) reference protein. The in vitro protein digestibility (IVPD) value of 83.3% and the calculated protein efficiency ratio (C-PER), 2.14, were slightly higher than those of sesame seeds and both values were lower than the IVPD and C-PER of 90.0% and 2.50, respectively, for ANRC casein.

Chlorinated pesticide residues in the total diet of Kuwait

Abstract Total diet of Kuwait was assessed for the residues of chlorinated pesticides. 140 core samples along with 90 additional samples (collected during 1995–96) were analyzed following US FDA multiresidue procedures. The results showed that 17.6% of the core samples contained detectable residues. Chlorpyrifos-methyl was present (ranging from 0.05 to 0.72 mg/kg) in most of the positive samples. Wheat flour was the single important source of this residue in the diet. Residues of chlorpyrifos, vinclozolin, procymidon and captan were also detected in some fresh fruits and vegetable. In general, residue levels were quite low and were significantly below the maximum residue limits (MRLs) established for these pesticides in food.

Nutrient contents of some traditional Kuwaiti dishes : proximate composition, and phytate content

Abstract Thirty-two Kuwaiti composite dishes were analyzed for their proximate composition and phytate content. The moisture content ranged from 89.5% in vegetable soup to 0.89% in rahash (a traditional sweet). The fat content varied from 0.99 to 29.2%. Fish dishes showed the highest protein content (20.9%) while vegetable soup had the lowest (1.19%). Carbohydrate content of the 32 dishes varied from 3.5% in fried fish to 53.3% in rahash. The ash content ranged from 5.1% in hallomi cheese to as low as 0.39% in legemat (sweet dumpling). Phytate content, ranged from 2835 mg/100 g in rahash to 32.6 mg/100 g in labnah (strained yoghurt).

Screening for β-agonists in sheep urine and eyes by an enzyme-linked immunosorbent assay in the state of Kuwait

Abstract Data are reported here on the assessment of the potential use of an enzyme-linked immunosorbent assay (ELISA) to monitor the presence of the β-agonist, clenbuterol in 142 samples of sheep urine and 53 samples of eye tissues from the same sheep. Data obtained showed that the clenbuterol levels ranged in the urine and eye tissues from not detected to 0.272 ppb and not detected to 1.54 ppb tissue, respectively. For confirmation, all samples that showed to be ELISA positive for clenbuterol residues were analyzed by GC–MS and were all found to be negative.

Toxic metals in imported fruits and vegetables marketed in Kuwait

Abstract The contentration of lead, cadmium, and mercury in 134 samples of imported fruits and vegetables marketed in Kuwait were determined using an atomic absorption spectrophotometer with a graphite furnace and the cold vapor technique. Results obtained showed that the concentration of these metal ions in most cases did not exceed the maximum permissible concentration of metals in fresh fruits and vegetables as restricted by some countries. Only a few samples of fruits and vegetables contained levels of mercury, cadmium, and lead which exceeded these maximum permissible levels.

Chemical composition and nutritional quality of sorghum flour and bread

Two Saudi Arabian sorghum cultivars, white and reddish white, were investigated for their chemical and nutritional quality. The two cultivars were similar in proximate composition (white 15.3% protein, reddish-white 15.9% protein), mineral profile, fatty acid composition, vitamin content (except vitamin-B12 was higher in reddish-white), in vitro protein digestibility (IVPD) and calculated protein efficiency ratio (C-PER). White sorghum had lower tannins (0.09% catechin equivalent) compared to the reddish-white (0.27% catechin equivalent). Lysine was the first limiting amino acid in both with chemical scores of 45 and 47 for the proteins of white and reddish-white cultivars, respectively. Baking had no effect on proximate, fatty acid and amino acid composition. However, it increased the Na and Ca contents but decreased the K, P, and pantothenic acid contents. Tannins were not detected in the breads. Breads fermented for 18 h had higher vitamin-B12 and pantothenic acid levels but lower P content than unfermented breads. A slight increase in tyrosine, lysine, methionine contents as well as C-PER was also observed in fermented bread.

Dietary intake of pesticides : State of Kuwait total diet study

The State of Kuwait conducted a total diet study (TDS) to determine the dietary intakes of selected pesticides. This paper reports the results of this study. A national food consumption survey was performed and core food lists for different population groups were established representing the total diet of the Kuwaiti population. Food items (table-ready) were purchased/prepared and analysed for their contents of organophosphate/organochlorine carbamate, benzimidazole and phenylurea pesticides according to the US FDA Pesticide Analytical Manual (PAM I). Dietary intakes of these pesticides are presented for 19 population groups, which range from infants to elderly adults. The intakes of selected population groups are compared with representative findings from the US FDA/TDS and data published from other countries. In general, the average daily intakes were well below acceptable limits, but higher than those reported from developed countries.