Acceptable Daily Intake Values Research Articles

Secret ingredients: who knows what's in your food?

British chef and food activist Jamie Oliver ignited a firestorm in January 2011 when he mentioned on the Late Show with David Letterman that castoreum, a substance used to augment some strawberry and vanilla flavorings, comes from what he described as “rendered beaver anal gland.”1 The next year, vegans were outraged to learn that Starbucks used cochineal extract, a color additive derived from insect shells, to dye their strawberry Frappuccino® drinks2 (eventually, the company decided to transition to lycopene, a pigment found in tomatoes3). Although substances like castoreum and cochineal extract may be long on the “yuck factor,”4 research has shown them to be perfectly safe for most people; strident opposition arose not from safety issues but from the ingredients’ origins. But these examples demonstrate that the public often lacks significant knowledge about the ingredients in foods and where they come from. This is not a new development; the public relationship to food additives has a long history of trust lost, regained, and in some cases lost again. The Federal Food, Drug, and Cosmetic (FD&C) Act of 19385 was passed shortly after the deaths of 100 people who took an untested new form of a popular drug, which contained what turned out to be a deadly additive.6 The new law was consumer oriented and intended to ensure that people knew what was in the products they bought, and that those products were safe. The law has been amended over the years in attempts to streamline and bring order to the sprawling task of assessing and categorizing the thousands of substances used in foods, drugs, and cosmetics. One result of this streamlining is that under current U.S. law, companies can add certain types of ingredients to foods without premarket approval from the thin-stretched Food and Drug Administration (FDA). In other words, there are substances in the food supply that are unknown to the FDA. In 2010 the Government Accountability Office (GAO) concluded that a “growing number of substances … may effectively be excluded from federal oversight.”7 Is this a problem? The answer depends on whom you ask.

Transfer of metals and metalloids from soil to shoots in wild rosemary (Rosmarinus officinalis L.) growing on a former lead smelter site: Human exposure risk

This study aimed at estimating exposition risks to wild rosemary used as herbs in the contaminated area of the former smelting factory of L'Escalette (South of Marseille, France). Metals and metalloids i.e. Pb, As, Sb, Zn, and Cu concentrations were analyzed in soils and in rosemary aerial parts (stems and leaves) on two sites: one heavily contaminated and the other far away from the pollution source, considered as reference. The metal and metalloid transfer into water during the brewing process of herbal tea was also determined. A mixed contamination by the above-cited contaminants was demonstrated in soils of the factory site, with average concentrations of 9253, 1127, 309, 2698 and 32mg/kg for Pb, As, Sb, Zn and Cu, respectively. However, metals and metalloids' transfer in rosemary aerial parts was limited, as bioaccumulation factors were under 1. Thus, Pb, As and Cu concentrations in leaves were below international regulation limits concerning ingestion of medicinal herbs (no regulation values available for Sb and Zn). This study highlighted that, if contaminated rosemary leaves were ingested, health risks may be limited since acceptable daily intake (ADI) for Pb, As, Sb and Cu (no ADI value available for Zn) will only be reached if very high quantities are consumed. Furthermore, we aimed to establish if this mixed contamination could alter rosemary's essential oil quality, and thereby the compositions of essential oils obtained from individuals on the heavily contaminated soil were compared to those obtained from the reference population. An increased biosynthesis of antioxidant compounds was favored in essential oils from rosemary individuals growing in contaminated site. Although the health risk of a long-term exposition of low level of the mixed contamination by rosemary ingestion is not easy to elucidate, the use of rosemary essential oils from contaminated site appears as safe.

Trigger values for investigation of hormonal activity in drinking water and its sources using CALUX bioassays

To screen for hormonal activity in water samples, highly sensitive in vitro CALUX bioassays are available which allow detection of estrogenic (ERα), androgenic (AR), progestagenic (PR), and glucocorticoid (GR) activities. This paper presents trigger values for the ERα, AR, PR, and GR CALUX bioassays for agonistic hormonal activities in (drinking) water, which define a level above which human health risk cannot be waived a priori and additional examination of specific endocrine activity may be warranted. The trigger values are based on 1) acceptable or tolerable daily intake (ADI/TDI) values of specific compounds, 2) pharmacokinetic factors defining their bioavailability, 3) estimations of the bioavailability of unknown compounds with equivalent hormonal activity, 4) relative endocrine potencies, and 5) physiological, and drinking water allocation factors. As a result, trigger values of 3.8ng 17β-estradiol (E2)-equivalents (eq)/L, 11ng dihydrotestosterone (DHT)-eq/L, 21ng dexamethasone (DEX)-eq/L, and 333ng Org2058-eq/L were derived. Benchmark Quotient (BQ) values were derived by dividing hormonal activity in water samples by the derived trigger using the highest concentrations detected in a recent, limited screening of Dutch water samples, and were in the order of (value) AR (0.41)>ERα (0.13)>GR (0.06)>PR (0.04). The application of trigger values derived in the present study can help to judge measured agonistic hormonal activities in water samples using the CALUX bioassays and help to decide whether further examination of specific endocrine activity followed by a subsequent safety evaluation may be warranted, or whether concentrations of such activity are of low priority with respect to health concerns in the human population. For instance, at one specific drinking water production site ERα and AR (but no GR and PR) activities were detected in drinking water, however, these levels are at least a factor 83 smaller than the respective trigger values, and therefore no human health risks are to be expected from hormonal activity in Dutch drinking water from this site.

Dietary exposure to a low dose of pesticides alone or as a mixture: The biological metabolic fingerprint and impact on hematopoiesis

Consumers are exposed to a mixture of pesticides through their food intake. These compounds are considered risk factors for human health, and the impact of dietary exposure to low doses of pesticide mixtures remains poorly understood. For this study we developed a mouse model to mimic consumer exposure in order to compare the effect of pesticides both alone or combined at doses corresponding to their Acceptable Daily Intake value. Female mice were exposed to pesticides throughout gestation and lactation. After weaning pups were fed the same pesticide-enriched diet their mothers had received for an additional 11 weeks. A metabonomic approach using 1H NMR-based analysis of plasma showed that exposure to each pesticide produced a specific metabolic fingerprint in adult offspring. Discriminant metabolites between groups were glucose or lactate, choline, glycerophosphocholine and phosphocholine. Interestingly, metabolite differences were observed as early as weaned animals that had not yet been directly exposed themselves. Studies of the hematopoietic system revealed that dietary exposure to one particular pesticide, endosulfan, produced a significant decrease in red blood cell and hemoglobin levels, consistent with hemolytic anemia. Moreover, cell signaling profiles of bone marrow progenitors were also clearly affected. Expression of cell signaling proteins such as P35, CDC27, FAK, P38 MAP kinase, calcineurin and caspase as well as proteins involved in the stability or structure of the cytoskeleton (vinculin, MAP2) was changed upon dietary exposure to pesticides. Finally, we found that dietary exposure to a mixture of pesticides had effects that differed and were often lesser or equal to that of the most efficient pesticide (endosulfan), suggesting that the effect of pesticide mixtures cannot always be predicted from the combined effects of their constituent compounds.

Safety evaluation of meso-zeaxanthin

Meso-zeaxanthin is a xanthophyll family member of carotenoids. Having closely related structures, meso-zeaxanthin, zeaxanthin and lutein have high concentration in macula and are believed to play a major role in protecting retinal constituents from free radicals. Due to the current technical difficulties in measurement, the presence of meso-zeaxanthin in human blood or tissues has not been reported except in human eyes, which has promoted scientists' interest in exploring potential health benefits of meso-zeaxanthin. Herein, we report a complete toxicological safety assessment of meso-zeaxanthin for use as an ingredient in food, dietary and nutritional supplements, as well as medical food. Assays of acute toxicity, genetic toxicity (Ames test, mice bone marrow erythrocyte micronucleus and mice sperm abnormality) and 90-day sub-chronic toxicity were performed. In the acute oral toxicity tests, maximum tolerable dose was more than 10.0 g/kg bw in SD rats and ICR mice, and showed no toxicological signs during the period of the study. The testing results for three terms of hereditary toxicity (Ames test, mice bone marrow erythrocyte micronucleus and mice sperm abnormality) were all negative. For 90-day feeding of meso-zeaxanthin at the dosage of 300 mg/kg/d in both male and female SD rats, there is no noticeable toxicological effects observed. Therefore, meso-zeaxanthin has no acute toxicity and no genotoxicity and the use of meso-zeaxanthin is safe at dose of 300 mg/kg bw/day in rats from a 90-day feeding study. After the application of a 100-fold safety factor, we obtained the ADI (acceptable daily intake) value of 3 mg/kg body weight per day.

Consumer and farmer safety evaluation of application of botanical pesticides in black pepper crop protection

This study presents a consumer and farmer safety evaluation on the use of four botanical pesticides in pepper berry crop protection. The pesticides evaluated include preparations from clove, tuba root, sweet flag and pyrethrum. Their safety evaluation was based on their active ingredients being eugenol, rotenone, β-asarone and pyrethrins, respectively. Botanical pesticides from Acorus calamus are of possible concern because of the genotoxic and carcinogenic ingredient β-asarone although estimated margins of exposure (MOE) for consumers indicate a low priority for risk management. For the other three botanical pesticides the margin of safety (MOS) between established acute reference doses and/or acceptable daily intake values and intake estimates for the consumer, resulting from their use as a botanical pesticide are not of safety concern, with the exception for levels of rotenone upon use of tuba root extracts on stored berries. Used levels of clove and pyrethrum as botanical pesticides in pepper berry crop production is not of safety concern for consumers or farmers, whereas for use of tuba root and sweet flag some risk factors were defined requiring further evaluation and/or risk management. It seems prudent to look for alternatives for use of sweet flag extracts containing β-asarone.

Organophosphorus Pesticide Residues in Vegetable and Soil Samples from Alau Dam and Gongulong Agricultural Areas, Borno State, Nigeria

The Concentrations of organophosphorus pesticide residues (dichlorvos, diazinon, chlorpyrifos, and fenitro-thion) were determine in some vegetables (spinach, lettuce, cabbage, tomato and onion) and soil samples from different depths within Alau Dam and Gongulong agricultural areas in Borno State, Nigeria. Samples collection and preparation were carried out using standard procedures. The concentrations of all the pesticides in the vegetables and soil samples were determined using GC/MS SHIMADZU (GC-17A) equipped with electron capture detector (ECD). The highest concentra-tions of diclorvos, diazinon, chlorpiryfos and fenithrothion in the Alau Dam and Gongulong agricultural areas were ob-served in the leaf of tomato, while the lowest concentrations were observed in the root of spinach. The concentrations of all the pesticides in the soil samples were observed to be higher at a depth of 21-30cm, while the lowest concentrations were observed at a depth of 0-10cm. The concentrations of all the organophosphorus pesticides in the vegetables and soil samples from the two agricultural areas were observed to be at alarming levels, much higher than the maximum residue limits (MRLs) and acceptable daily intake values (ADIs) set for vegetables and soil by the Cordex 2009 (WHO and FAO). The occurrence of pesticides in the vegetables and soil samples is a major threat to human that depends on these vegetables as food. Hence, the need for continuous monitoring is recommended so as to regulate the used of this pesticide in the study areas.

Residue Behavior of Combination Mix Formulations in/on Bittergourd and Their Efficacy Against Melon Fruitfly

Persistence behavior of three combination mix formulations of insecticides viz. chlorpyriphos + cypermethrin (Action-505), profenofos + cypermethrin (Roket 44EC) and triazophos + deltamethrin (Anaconda) and their bioefficacy against melon fruitfly were studied in bittergourd fruits following spray application. Half-life values of the constituent insecticides calculated from first order dissipation kinetics were ~2-3 days. Based on acceptable daily intake values, safe waiting period of 3-days is suggested for all the three combination mix formulations at recommended dose of application. Anaconda (1 L/ha) was found to be most effective against Melon fruitfly as it gave 11.72 % (number/number) and 10.93 % (weight/weight) damage as compared to control 41.13 % and 41.16 %, respectively. Anaconda at lower and higher dose (1 and 2 L/ha) was not significantly different. Rocket (2 L/ha) and Action 505 (2 L/ha) were also found effective.

Bioaccessibility of pesticides and polychlorinated biphenyls from house dust: in-vitro methods and human exposure assessment

Semi-volatile chemicals like pesticides and polychlorinated biphenyls (PCB) tend to accumulate in house dust. This may result in residues of some parts per million (p.p.m.), closely associated with health impairments and diseases like cancer. To explain these associations, we must establish whether a relevant absorption from house dust into human organisms occurs, and most crucially the release of chemicals, that is, their bioaccessibility. Digestive as well as dermal bioaccessibilities were examined using in-vitro methods. On average, the digestive bioaccessibility was ~40% for the pesticides and ~60% for the PCB. The dermal penetration availability reached ~60% for the pesticides and ~70% for the PCB (percentages of the concentrations in the dust). Based on the bioaccessibility, an estimate of internal exposure was calculated and expressed as percentages of acceptable or tolerable daily intake (ADI/TDI) values. Exposure via the respiratory tract proved to be very low. Exposure via the digestive tract had maximum values of 4% for pesticides and 12% for PCB. Dermal exposure was much higher. Even for average concentrations in house dust (≈0.5 p.p.m.), children exposed to DDT and PCB showed up to 300% of the ADI/TDI values, and adults about 60%. With high concentrations of contaminants in house dust, the maximum doses absorbed through the skin reached 5000%.

Analysis of 20 trace and minor elements in soy and dairy yogurts by ICP-MS

The content of 20 trace and minor elements in soy and dairy yogurts consumed in Spain has been determined using inductively coupled plasma-mass spectrometry (ICP-MS) after microwave digestion. This work presents two goals: a) to determine the nutritional value in terms of minor elements content, using recommended daily allowance data; b) to determine the levels of trace toxic elements and compare them with the acceptable daily intake values. The developed analytical method was validated by using both milk certified reference materials and recovery experiments over different yogurt samples, obtaining satisfactory results in all cases. In addition, a comparison between the levels of minor elements found in soy and dairy yogurts was performed. Much higher concentrations of Cu and Mn were found in soybean products (up to 30-fold higher) and minor differences were observed in the content of Fe and Zn. Other minor element found at higher concentrations in soy yogurts was Ni (effect usually observed in plant-origin foods), which was determined at levels up to 450ngg−1 in some samples. Finally, the levels of toxic elements were very low, even below the detection limit in some cases.

Artificial sweeteners - a review.

Now a days sugar free food are very much popular because of their less calorie content. So food industry uses various artificial sweeteners which are low in calorie content instead of high calorie sugar. U.S. Food and Drug Administration has approved aspartame, acesulfame-k, neotame, cyclamate and alitame for use as per acceptable daily intake (ADI) value. But till date, breakdown products of these sweeteners have controversial health and metabolic effects. On the other hand, rare sugars are monosaccharides and have no known health effects because it does not metabolize in our body, but shows same sweet taste and bulk property as sugar. Rare sugars have no such ADI value and are mainly produced by using bioreactor and so inspite of high demand, rare sugars cannot be produced in the desired quantities.

Potential exposure of perfluorinated compounds to Chinese in Shenyang and Yangtze River Delta areas

Environmental contextA total of 21 perfluorinated compounds (PFCs) including PFOS were quantified in river waters, sewage, sea waters, shallow ground waters as well as fish and domestic poultry, focussed on the main river basins in Shenyang and the Yangtze River Delta areas, China. The distribution characteristics of PFCs in the aquatic environment and evaluation of the potential risk for human health via the diet of fish was discussed. Comprehensive research was carried out using the world leading knowledge about PFOS-related chemicals in AIST, Japan to enable reliable evaluation of PFOS risk in Chinese environments, supported by ISO25101. AbstractA total of 21 perfluorinated compounds (PFCs) were quantified in water and biota samples collected from Shenyang in North-east China and the Yangtze River Delta area in East China. The human health risk owing to intake of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) via fish and domestic poultry dietary was evaluated. The total PFC concentration (∑PFC) in water samples from the rivers in Shenyang averaged 5.32 ng L–1, with PFOS and PFOA as the predominant compounds. The urban sewage could be the source of PFOS and perfluorohexane sulfonate (PFHxS) in the surface waters. The total PFCs in water samples from the Yangtze River Delta area ranged from 42.4 to 170 ng L–1. The highest concentrations of most PFCs were observed in waters from the Shanghai section of the Yangtze River. In the biota samples, PFOS and PFUnDA (perfluoroundecanoic acid) were the most abundant. The acceptable daily intake (ADI) and hazard ratio (HR) values for PFOS and PFOA intake through the diet of fish and poultry in the studied areas were calculated, and showed that the HR values for PFOS and PFOA are all less than 1.0 for both the areas.

Artificial Sweetener Intake of Korean Children is Insignificant

PP-30-127 Background/Aims: With a recent increase in intake of sweetened beverage among going school children, we attempted to assess dietary intake of artificial sweeteners (AS: aspartame, acesulfame-K, saccharin sodium). Because the previously estimated intake of AS among children was minimal, we focused on intake in consumer (C) group. Methods: A food frequency questionnaire was developed to estimate the intake of artificially sweetened beverages and snacks on the basis of the result of AS monitoring by Korea Food and Drug Administration (KFDA). In all, 28 schools each were selected for elementary, junior high, and high schools in Seoul, Korea, using a stratified multistage sampling method. Students in a class from second and fifth grades at elementary school, and second grade at junior high school and high school were surveyed for the frequency and amount of artificially sweetened beverages and snacks during 1 week before the survey. The survey was repeated for 3 seasons, from June through December 2009, to compensate for any possible seasonal effect. Sweetener intake was estimated by using AS database of KFDA and compared with the acceptable daily intake (ADI). Results: A total of 10,099 children responded to the survey. The mean AS intake of group C children was 0.25 ± 0.48 mg/kg bw/d, 0.18 ± 0.44 mg/kg bw/d, and 0.22 ± 0.25 mg/kg bw/d for aspartame, acesulfame-K, and saccharin sodium, respectively. Although these values were 1.5–5.5 times higher than those of all children, the corresponding values of ADI were only 0.63%, 1.23%, and 4.42% of respective ADI values set by JECFA. Even the 95th percentile values of ADI were far lower than the safety limit: 2.48%, 4.86%, and 15.59% for aspartame, acesulfame-K, and saccharin sodium, respectively. Conclusion: This study revealed that the AS intake through beverages and snacks among children in Korea is insignificant and very safe. This study was supported by R&D fund of KFDA (0808KFDA999-101).

What can we learn from monitoring PCBs in the European eel? A Belgian experience

Between 2000 and 2007 pooled muscle tissue samples of the European eel ( Anguilla anguilla) from 48 sites in Flanders (Belgium) were analysed for 30 polychlorinated biphenyl (PCB) congeners. There was a large variation between individual sites (range 11–7752 ng/g wet weight (ww) for the sum of the ICES 7 PCBs), eels from the River Meuse basin (mean 1545 ng/g ww) being considerably more polluted than those from the River Scheldt (615) and IJzer (61) basins. Overall, PCB 153, PCB 138 and PCB 180 were the most prominent congeners, however PCB patterns varied between the monitored locations. Analysis of the weight percentage of congeners demonstrates obvious differences in PCB composition between sites, indicating differential sources of pollution. Due to the variation in patterns, atmospheric fallout does not seem to be the main source of the PCB spread, but instead both local and upstream sources linked to industrial activities seem to be the main cause for PCB presence in Flanders. Considering the levels of the Sum 7 PCBs, eels are not compliant with the Belgian legal limits for consumption (75 ng/g ww) in 71% of the sites. Regular consumption of eels from polluted sites leads to a considerable excess of the WHO Acceptable Daily Intake value. Consumption of wild eels should by all means be prevented, as it presents risks for human health, especially for local anglers consuming their catch.

Investigation of the Toxic Functional Group of Cephalosporins by Zebrafish Embryo Toxicity Test

2-mercapto-5-methyl-1,3,4-thiadiazole (MMTD) is the 3'-side chain of cephalosporin including cefazolin sodium (CFZL) and cefazedone (CFZD). It is not only present in finished products as the residual precursor, but also produced through drug degradation. Performing the zebrafish embryo toxicity test, we evaluated the toxicity effects of cefazolin sodium, cefazedone, their synthetic precursors and intermediates. Our results suggest that the teratogenic effect of cefazedone and cefazolin sodium on zebrafish embryonic development is associated with the structure of MMTD. They mainly interfere with the development of tissues and organs derived from embryonic ectoderm and mesoderm. We further consider the rationality of the quality control limit of MMTD (1.0%) in the specification. As the acceptable daily intakes (ADIs) of cefazolin is 10 µg/kg per day 16 and the minimum teratogenic concentration of MMTD is tenfold lower than that of cefazolin sodium, we recommend that the acceptable daily intakes of MMTD should be 1 µg/(kg day). In general, the therapeutic dose of cefazolin sodium is 2-4 g/day. Based upon the calculation of MMTD quality control limits (1.0%), MMTD intake can be 20-40 mg/day, which will be much more than the acceptable daily intake value of 1 µg/(kg day). Thus, MMTD should be recommended as a specified impurity and qualified as serious again.

Safety Evaluations of the Cry1Ia1 Protein Found in the Transgenic Potato ‘SpuntaG2’

The transgenic potato ‘SpuntaG2’ (Solanum tuberosum), which is resistant to potato tuber moth (Phthorimaea operculella), was subjected to protein safety evaluations including protein equivalency tests for the Cry1Ia1 protein from ‘SpuntaG2’ and bacterially produced Cry1Ia1, toxicity and allergenicity evaluations of Cry1Ia1 protein, and compositional equivalency of ‘SpuntaG2’ compared with non-transgenic ‘Spunta’. Western blot analysis and biological activity assays showed molecular and functional equivalency between ‘SpuntaG2’-derived Cry1Ia1 protein and bacteria-derived Cry1Ia1 protein. Comparison of the Cry1Ia1 amino acid sequence to known amino acid sequences revealed no significant homology to known toxins or known allergens. Acute toxicity studies using rodents were used to calculate an acceptable daily intake (ADI) value of 20 mg·kg−1 body weight per day. The ADI value was then used to calculate a margin of exposure (MOE) of 2,222,222, which is more than 22,000 times greater than the commonly used target MOE of 100. Digestibility and thermostability assays determined that Cry1Ia1 was fully digested within 30 s of exposure to pepsin and inactive after 3 to 4 minutes at 100 °C, indicating that it would not be a potential allergen. Compositional analyses revealed no difference between ‘SpuntaG2’ and non-transgenic ‘Spunta’. These results strongly indicate that the Cry1Ia protein and the transgenic potato ‘SpuntaG2’ is not a human health risk.

Human health risk assessment of pharmaceuticals in water: An uncertainty analysis for meprobamate, carbamazepine, and phenytoin

This study presents a step-wise development of a quantitative pharmaceutical risk assessment (QPhRA, hereafter) framework, including Monte Carlo uncertainty analysis for meprobamate, carbamazepine, and phenytoin during (1) accidental exposures of stream water and fish consumption and (2) direct ingestion of finished drinking water for children and adults. Average hazard quotients of these pharmaceuticals (i.e., the ratio of values of chronic daily intake to acceptable daily intake) were found to lie between 1×10−10 and 3×10−5 and 99th percentile values of hazard quotients were found to be less than 1×10−4 for both sub-populations, indicating no potential risks of adverse effects due to pharmaceuticals exposures. In addition, pharmaceutical concentrations were also observed to be lower than their respective calculated acceptable daily intake-equivalent drinking water levels, indicating no potential human health risks. To the authors’ knowledge, for the first time in QPhRA studies, this study has attempted to characterize and quantify effects of factors, such as considerations for sensitive sub-populations using subpopulation-specific toxic endpoints and use of pharmaceutical concentrations in stream and finished drinking waters on risk estimates. Acceptable daily intake was observed to be the primary contributor (>93% variance contribution) in the overall uncertainties of estimates of hazard quotients, followed by fish consumptions and pharmaceutical concentrations in water. Further research efforts are required to standardize use of acceptable daily intake values to reduce large variability in estimation of hazard quotients.

URBAN DIETARY HEAVY METAL INTAKE FROM PROTEIN FOODS AND VEGETABLES IN DAR ES SALAAM

Contamination of food and food products by heavy metals has made dietary intake as one of the major routes of these harmful elements to human beings. The human dietary intake of heavy metals cadmium, copper, lead and zinc from protein-foods (beans, meat, fish, milk) and green vegetables consumed daily from restaurants and street food-vendor kiosks in Dar es Salaam were determined using the Total Diet Study (TDS) method. The cooked food was bought from the restaurants and street food-vendors at several city locations (i.e. Buguruni, Manzese, Mwenge, Temeke and Ubungo) over several months and analyzed. Heavy metal concentrations were determined by Atomic Absorption Spectrophotometry (AAS) after wet digestion of the edible portions of pooled samples of the foodstuff. The results showed significant variation in heavy metal concentration among the foodstuff and at the different locations. The results were compared to the FAO/WHO levels for Acceptable Daily Intake (ADI) and Provisional Tolerable Weekly Intake (PTWI) to estimate risk of toxicity and to the US Recommended Dietary Allowance (RDA) and/or Estimated Safe and Adequate Daily Dietary Intake (ESADDI) for a deficiency in intake. The average weekly dietary intake of cadmium and lead from protein-foods and vegetables ranged from 0.20 - 0.42 µg/kg-bw/week (i.e. 2.82 - 6.00% of PTWI) and 4.77 - 9.83 µg/kg-bw/week (i.e. 68.1 – 140.4% of PTWI) respectively. These dietary intakes were below the ADI values of 0.5 µg/kg-bw/day and 3.6 µg/kg-bw/day of the WHO for cadmium and lead respectively. The daily dietary intake of zinc and copper at all the locations were also below the ADI for these elements, the average being 21.5% for copper and 19.8% for zinc. The results show clearly that the daily urban dietary intake of copper and zinc, from protein foods and vegetables along main streets at the above locations, was acceptable. Keywords : Heavy metal, dietary intake, protein foods, vegetables, Dar es Salaam Tanz. J. Sci . Vol 36 2010, 85-94

Exposure Risk Assessment of the Emissions of Wood Preservative Chemicals in Indoor Environments

AbstractA collaborative study was undertaken to evaluate the sustainability of a new generation of biocides for the treatment of timbers in buildings and to validate the recyclability of the treated timbers. The evaluation included an assessment of the impact of emissions of the wood treatment chemicals during the service life of timbers and recycled wood based products. This involved emission testing of active substances (propiconazole, tebuconazole, permethrin and dichlofluanid) and volatile organic compounds (VOCs) from timber pretreated or coated using formulated products. The German AgBB method for evaluating VOC emissions from construction products was used to discuss the relative risk of the treated timbers. The emission rates of the active substances from the treated timbers were compared to the ADI (Acceptable Daily Intake) values given in the draft reports from the EU Biocides Directive, 98/8/EC, to determine the exposure risk to building occupants. As a part of this study, the emissions of the active substances from the stud frame of a newly built test cabin were monitored over a two year period.

Chemical Contamination of Green Turtle ( Chelonia mydas ) Eggs in Peninsular Malaysia: Implications for Conservation and Public Health

BackgroundPersistent organic pollutants (POPs)—such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs)—and heavy metals have been reported in sea turtles at various stages of their life cycle. These chemicals can disrupt development and function of wildlife. Furthermore, in areas such as Peninsular Malaysia, where the human consumption of sea turtle eggs is prevalent, egg contamination may also have public health implications.ObjectiveIn the present study we investigated conservation and human health risks associated with the chemical contamination of green turtle (Chelonia mydas) eggs in Peninsular Malaysia.MethodsFifty-five C. mydas eggs were collected from markets in Peninsular Malaysia and analyzed for POPs and heavy metals. We conducted screening risk assessments (SRAs) and calculated the percent of acceptable daily intake (ADI) for POPs and metals to assess conservation and human health risks associated with egg contamination.ResultsC. mydas eggs were available in 9 of the 33 markets visited. These eggs came from seven nesting areas from as far away as Borneo Malaysia. SRAs indicated a significant risk to embryonic development associated with the observed arsenic concentrations. Furthermore, the concentrations of coplanar PCBs represented 3 300 times the ADI values set by the World Health Organization.ConclusionsThe concentrations of POPs and heavy metals reported in C. mydas eggs from markets in Peninsular Malaysia pose considerable risks to sea turtle conservation and human health.