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Purpose. To determine the status of selenium, dl-alpha-tocopherol and all-trans-retinol in children and adults living in the Al-Kharj district, using serum and toenail samples. Design. A cross-sectional study. The samples were collected randomly from 1255 healthy Saudi subjects attending the Primary Health Care Units (PHCUs), Al-Kharj for different common health problems. Materials and methods. Serum and toenail selenium concentrations were measured using an atomic absorption spectrophotometer coupled with an electrothermal temperature controller, whereas the levels of dl-alpha-tocopherol, all-trans- retinol and malondialdehyde in serum were determined using high-performance liquid chromatography. Results. The arithmetic means of selenium, dl-alpha-tocopherol and all-trans- retinol in serum for the tested population were 102.165+/-22.936 microg l[-1] (n = 1255, range 18.25-210.12 microg l[-1]), 22.715+/-6.908 micromol l[-1] (n = 1250, range 2.53-79.44 micromol l[-1]) and 1.601+/-0.802 micromol l[-1] (n = 1256, range 0.39-13.99 micromol l[-1]), respectively. Toenail selenium levels were 0.613+/-0.217 microg g[-1] (n = 1069, range

Background: This study evaluated the effect of caffeine consumption on the success rate of pregnancy and various in vitro fertilization (IVF) performance parameters., Material/methods: Serum and follicular fluid samples were collected from 619 women undergoing IVF treatment (2002-2003). Caffeine assessment was based on measuring the levels of caffeine in serum and follicular fluid and on the number of coffee or tea or caffeinated drinks consumed per day., Results: A total of 97.3% of participants reported the consumption of caffeinated drinks such as coffee, tea and soft drinks. Their average caffeine consumption was 455.82 mg/day (range: 3.71-3561 mg/day). Coffee was the primary source of caffeine intake. The average caffeine levels in serum (0.913 µg/ml) were significantly higher than in follicular fluid (0.701 µg/ml). After controlling for various potential confounding variables, no association was found between coffee or tea consumption and the success rate of pregnancy. Looking at the effect of caffeine consumption on the IVF performance parameters, we found that the number of eggs decreased as the caffeine serum levels increased (P=0.011). An increase in coffee consumption was positively associated with the number of aborted pregnancy (P=0.007), while the number of good embryo decreased with high tea consumption (P=0.015)., Conclusions: Though no association was seen between coffee or tea consumption and pregnancy rate, this study is the first to report that caffeine can reach the follicular fluid and there is a suggestive evidence of its possible harmful role on the consequences of reproductive process. This clearly warrants further investigation.

This study is designed to investigate the impact of DNA damage on pregnancy and fertilization rate outcome in a sub-sample of women undergoing IVF treatment. Blood and follicular fluid samples (n = 60) were analyzed for DNA adducts. While no BPDE-DNA adducts were detected, other unknown lipophilic adducts were seen in blood and follicular fluid. Women who failed to achieve pregnancy had higher DNA adducts in follicular fluid than those who succeeded (p < 0.05). Follicular fluid cotinine levels were associated with DNA adduct levels in blood and follicular fluid (p < 0.05). Evaluation of DNA damage resulting from oxidative stress could have a role in predicting IVF success rate.

Background: Although p,p'-dichlorodiphenyltrichloroethane (DDT) is banned for agricultural purpose in Saudi Arabia, it is occasionally used to control vector-borne diseases in certain regions of the country., Material/methods: A case-control study was designed to investigate the possible effects of DDT and its metabolites on pregnancy and fertilization rate outcome. The study population was composed of 619 Saudi women (age 19-50 years) who sought in-vitro fertilization (IVF) treatment between 2002 and 2003., Results: p,p'-DDE, the main metabolite of DDT, was the most frequently detected residue in serum or follicular fluid, with mean values of 1.646 microg/L and 0.407 microg/L, respectively. After controlling for many potential confounding variables, multiple logistic regression analysis revealed no association between pregnancy outcome or fertilization rate and p,p'-DDE levels in serum or follicular fluid., Conclusions: The inability to identify an effect may be related to the comparatively low concentrations of DDE in our population. But because p,p'-DDE was detected in the serum of 77.7% our participants, it should be considered as a matter of public heath concern. Currently there is no active source of DDT in our region; therefore, further studies are needed to identify sources in order to develop preventive measures because we can not exclude its potential reproductive toxicity.

This study examined the chemopreventive effect of Nigella sativa and some of its antioxidant constituents on a number of colon cancer biomarkers in rats induced with azoxymethane (AOM). Sixty male Sprague-Dawley rats were randomly assigned into ten subgroups: vehicle (1-5) and experimental (6-10). The rats in each group were fed one of the following diets: basal diet, (200 mg/kg) Nigella sativa, (0.2 mg/kg) selenium, (1.2 mg/kg) all-trans-retinol plus (100 mg/kg) DL-alpha-tocopherol and (10 mg/kg) thymoquinone, respectively. Only rats in subgroups 6-10 were injected with AOM (15 mg/kg) once per week for 2 weeks. Both groups were fed their respective diets for 5 weeks. Then they were killed and examined for colonic aberrant crypt foci (ACF). Our result showed that only vitamin supplementation was effective on ACF. Nigella sativa revealed inhibitory effects only on DNA damage (day 34) in the AOM-treated rat group. Alternatively, selenium, thymoquinone and vitamins inhibited the MDA content in the liver. Although the exact mechanisms involved in the protective role of Nigella sativa against the initiation of colon carcinogenesis are not clearly understood, the results suggest that its inhibitory effects might depend on the combined competitive inhibition of various antioxidant constituents of this plant., ((c) 2008 John Wiley & Sons, Ltd.)

We investigated the effect of lead, cadmium and mercury exposure on pregnancy and fertilization rate outcome among 619 Saudi women (age 19-50 years) who sought in-vitro fertilization (IVF) treatment between 2002 and 2003. The concentrations of lead, cadmium and mercury were measured in both blood and follicular fluids. At levels well below the current US occupational exposure limit guidelines (40microg/dL) and even less than the current Centers for Disease Control and Prevention level of concern for preventing lead poisoning in children (10microg/dL), blood lead level was negatively associated with fertilization outcome in both adjusted and unadjusted logistic regression models. We found that among various demographic, socioeconomic and environmental factors, fish consumption was positively associated with blood lead levels. These results support the hypothesis that a raised blood lead level affects infertility and intervention to reduce the lead exposure might be needed for women of reproductive age. The present results also revealed unexpected finding - the positive relationship between follicular cadmium levels and fertilization outcome, which points to the necessity for further investigation. Though adverse effect of mercury on pregnancy outcome or fertilization rate was not evident in this study, mercury5.8microg/L (EPA safety limit) was found in the blood and follicular fluid of 18.7% and 8.3% of the women, respectively. Concerns about its possible adverse effects on the physiology of reproduction or fetal development cannot be ruled out. It should be noted that skin-lightening creams and dental amalgam were important contributors to mercury exposure. Such finding is alarming and priority for further studies are, urgently, needed.

We established a reference range for dl-alpha-tocopherol and all-trans-retinol in a Saudi population previously selected for a cross-sectional study evaluating selenium and vitamin status. Concentrations of dl-alpha-tocopherol and all-trans-retinol were 0.999 +/- 0.31 mg/dL (n=994, range 0.11-3.42 mg/dL) and 49.14 +/- 24.15 micro/dL (n=1000, range 11.20-400.85 microg/dL), respectively. The levels of dl-alpha-tocopherol and all-trans-retinol in serum were determined by high-pressure liquid chromatography (HPLC) equipped with a UV detector. We took the influence of age and gender into account. Both had significant effect on the levels of all-trans-retinol in serum, except in the case of dl-alpha-tocopherol, where no gender related effect was found. We used the 5th and 95th percentiles as reference limits. Based on these criteria, it was found that these reference limits differed between genders for all-trans-retinol. Our lower and upper limits for dl-alpha-tocopherol classified by three age groups were very close to the normal range of 0.5-1.6 mg/dL, as found in previous studies. The 5th percentile of all-trans-retinol in both males and females, stratified by age, was close to a level of <20 microg/dL, which could be regarded as a mild vitamin A deficiency according to WHO criteria. But the value corresponding to the 95th percentile was higher than the upper limit of vitamin A's normal range of 70 microg/dL, suggesting a potentially harmful high dietary intake of vitamin A. The reference intervals elaborated here may help in the assessment of the vitamin status and in detecting subjects at risk of developing pathologies associated with either excess intake or deficiency.

This study was designed to determine the status of selenium, dl-alpha-tocopherol, and all-trans-retinol in adults living in Al-Kharj district using serum and toenail samples, and to look for possible association between these parameters and the etiology of endemic diseases in the same area. For this purpose, we examined a cross section of samples of 743 healthy Saudi adults on routine visits to the Primary Health Care Unites (PHCUs) for different common health problems. The arithmetic mean for selenium, dl-alpha-tocopherol, and all-trans-retinol in serum and toenail selenium levels were 107.045 +/- 23.045 microg/l (n = 743, range 52.600-210.120 microg/l), 1.053 +/- 0.324 mg/dl (n = 737, range 0.29-3.42 mg/dl), 52.561 +/- 25.671 microg/dl (n = 743, range 11.20-400.85 microg/dl), and 0.634 +/- 0.221 microg/g (n = 691, range < DL - 1.797 microg/g), respectively. The average serum selenium concentration seems to be satisfactory and compares favourably with high selenium intake countries. Although none of our participants exhibited serum selenium deficiency (< 45 microg/l), 41% of our participants had toenail selenium < 0.56 microg/g reported low levels in the previous study. The mean serum dl-alpha-tocopherol concentrations fall within the upper limit of the normal range of > 0.698-1.981 mg/dl for alpha-tocopherol as found in previous studies. On the other hand, the mean serum all-trans-retinol is higher than the normal range (20-30 microg/dl). None had exhausted retinol stores trans-retinol and MDA levels in the serum was found as a sign of peroxidative lipid damage, confirming the role of vitamin A in reducing oxidative stress. Our data also revealed a link between the status of selenium, dl-alpha-tocopherol and all-trans-retinol and a number of health problems. However, these observations need larger epidemiological studies for further confirmation.

Background: Selenium is an essential element, and a cofactor required to maintain glutathione peroxidase activity. Its deficiency may induce modification in the cellular antioxidative status and the appearance of different diseases. Previous studies in Al-Kharj reported low selenium levels in the soil and the milk of lactating mothers living in that area., Methods: A cross-sectional study was carried out to determine the status of selenium, dl-alpha-tocopherol, and all-trans-retinol in 513 Saudi children living in Al-Kharj district using serum and toenail samples., Results: The prevalence of children with serum selenium below the threshold limit of clinical importance in coronary and cardiovascular diseases (45 microg/l) was only 1.4%, while 53.4% of the tested children had toenail selenium >0.56 microg/g, which is considered a low level as indicated in a previous study. DL-alpha-tocopherol deficiency (<0.5 mg/dl) was found only in 3.1%. However, none of the children in this study had a severe all-trans-retinol deficiency (<10 microg/dl) and the percentage of children with marginal deficiency <20 microg/dl was 5.5%., Conclusion: It seems that the geographical location of primary health care units (PHCUs) is the most important factor in influencing the selenium status of these children. This implies variations in food habits. Serum and toenail selenium concentrations were significantly related which can both reflect dietary selenium intake. Although our results suggest an adequate vitamin A status, we found interestingly that 10.9% of the children had retinol >50 microg/dl. This suggests that a high dietary intake of vitamin A might have a harmful effect. Further work is necessary to determine whether the hypervitaminosis A in children reflects an excessive dietary intake of retinol. A significant negative association was also found between dl-alpha-tocopherol and all-trans-retinol and malonaldehyde (MDA) levels in the serum of children population. This confirms their role in reducing oxidative stress.

Fair & Lovely is an over-the-counter skin-lightening cream sold widely in Saudi markets. Its mercury content is 0.304+/-0.316 microg/g, in the range of 0.102 to 0.775 microg/g. This study was designed to evaluate its toxic effects on mice. The cream was applied on mice for a period of 1 month at different intervals. Mercury levels were measured in the liver, kidney, and brain tissue samples of a total of 75 adult female CD1 mice by Atomic Absorption Spectrophotometer coupled to a Vapor Generator Accessory. The mean mercury concentrations in the tissues of the treated mice were 0.193+/-0.319 microg/g; whereas for the control group, it was 0.041 microg/g+/-0.041microg/g. While the kidney was found to have the highest mercury content, the brain was found to have the lowest content. Treated mice showed a significant reduction in body weight. Marked histological changes were clearly noted in the kidney and, to a lesser extent, in the brain and liver. These results indicate that although Fair & Lovely mercury content is less than the U.S. Food and Drug Administration (FDA) permissible limits histopathological changes in the brain, kidney, and liver tissues are evidence of its possible toxicity.

The use of mercury containing skin-lightening creams are becoming increasingly popular among dark-skinned women. The long-term use of certain brands may cause serious health effects over the years. In the present study, we investigated the dermal absorption of mercury and its accumulation in the tissues of albino and pigmented mice treated with two brands of mercury containing skin-lightening creams for a period of one months at different intervals. The mean +/- SD of mercury in the selected brands were: (1) Fair & Lovely (0.304 +/- 0.316 microg/g); and (2) Rose (77513.0 +/- 71063.0 microg/g). Mercury levels were measured in a total of 133 and 144 liver, kidney and brain tissue samples of albino and pigmented mice respectively by the Atomic Absorption Spectrophotometer coupled to Vapour Generator Accessory. In both strains, we found that the mercury concentration in the tissues of mice treated with Rose skin-lightening cream samples was significantly higher than those treated with Fair & Lovely skin lightening cream. Looking at the mercury concentration in the tissue samples with respect to the application of skin lightening creams at different intervals, the highest mercury concentrations were found in the tissues of albino and pigmented mice treated three times a day. On the other hand, the lowest mercury concentrations were found in the tissues of mice treated once a week. Despite the brand of skin-lightening cream that was applied, the study indicated that mercury was readily absorbed through the skin of both albino and pigmented mice as evidenced with its accumulation in the brain, kidney and liver tissues where the kidney had the highest mercury content and brain had the lowest (it P < 0.0001). Significant differences in the mercury levels were observed between the albino and pigmented mice. This emphasizes the protective role of melanin against mercury toxicity. Results of this study stresses the potential harm of these mercury containing skin-lightening creams regardless of their mercury contents especially for women who apply these creams frequently or for extended periods. Permanent nephrological or/and neurological deficits may occur if the damage is severe and diagnosis and treatment are delayed.

Rose skin-lightening cream with a mercury content of 77,513 +/- 71,063 ppm was selected and applied on mice for a period of 1 month at different intervals. Mercury levels were measured in a total of 58 liver, kidney, and brain tissue samples by atomic absorption spectrophotometer coupled to vapor generator accessory. The mean mercury concentration in the tissues of treated mice was 67,472 +/- 70,181 microg/g in the range of 0.391-288.759 microg/g. Looking at the mercury concentration in the tissue samples with respect to the application of skin lightening creams at different intervals, the highest mercury concentrations were found in the tissues of mice treated 3 times a day (116.806 +/- 83.182 microg/g, ranges 5.989-288.759 microg/g). On the other hand, the lowest mercury concentrations were found in the tissues of mice treated once a week (16.450 +/- 26.168 microg/g, ranges 0.391-95.642 microg/g). Histopathological changes were clearly seen in the brain, kidney, and liver sections of all treated mice. The severity of pathological changes observed in tissues increased with increasing the number of applications. It is evident that repeated application of Rose skin-lightening creams could induce permanent damage to the kidneys, brain, and liver. This study emphasizes the potential toxicity of mercury skin-lighting creams and the importance of discontinuing their manufacture and use.