Dietary exposure assessment of Danish consumers to dithiocarbamate residues in food: a comparison of the deterministic and probabilistic approach

Probabilistic and deterministic estimates of the acute and chronic exposure of the Danish populations to dithiocarbamate residues were performed. The Monte Carlo Risk Assessment programme (MCRA 4.0) was used for the probabilistic risk assessment. Food consumption data were obtained from the nationwide dietary survey conducted in 2000--02. Residue data for 5721 samples from the monitoring programme conducted in the period 1998--2003 were used for dithiocarbamates, which had been determined as carbon disulphide. Contributions from 26 commodities were included in the calculations. Using the probabilistic approach, the daily acute intakes at the 99.9% percentile for adults and children were 11.2 and 28.2 microg kg(-1) body weight day(-1), representing 5.6% and 14.1% of the ARfD for maneb, respectively. When comparing the point estimate approach with the probabilistic approach, the outcome of the point estimate calculations was generally higher or comparable with the outcome of the probabilistic approach at the 99.9 percentile (consumers only). The chronic exposures for adults and children were 0.35 and 0.76 microg kg(-1) body weight day(-1) at the 99.9 percentile, representing 0.7% and 1.5%, respectively, of the acceptable daily intake for mancozeb and maneb at 50 microg kg(-1) body weight.     

Dietary exposure assessment of Danish consumers to dithiocarbamate residues in food: A comparison of the deterministic and probabilistic approach

Probabilistic and deterministic estimates of the acute and chronic exposure of the Danish populations to dithiocarbamate residues were performed. The Monte Carlo Risk Assessment programme (MCRA 4.0) was used for the probabilistic risk assessment. Food consumption data were obtained from the nationwide dietary survey conducted in 2000–02. Residue data for 5721 samples from the monitoring programme conducted in the period 1998–2003 were used for dithiocarbamates, which had been determined as carbon disulphide. Contributions from 26 commodities were included in the calculations. Using the probabilistic approach, the daily acute intakes at the 99.9% percentile for adults and children were 11.2 and 28.2 μg kg^?1 body weight day^?1, representing 5.6% and 14.1% of the ARfD for maneb, respectively. When comparing the point estimate approach with the probabilistic approach, the outcome of the point estimate calculations was generally higher or comparable with the outcome of the probabilistic approach at the 99.9 percentile (consumers only). The chronic exposures for adults and children were 0.35 and 0.76 μg kg^?1 body weight day^?1 at the 99.9 percentile, representing 0.7% and 1.5%, respectively, of the acceptable daily intake for mancozeb and maneb at 50 μg kg^?1 body weight.     

Probabilistic assessment of the cumulative dietary acute exposure of the population of Denmark to organophosphorus and carbamate pesticides

Organophosphorus and carbamate pesticides are acetylcholinesterase-inhibiting pesticides and as such have a common mode of action. We assessed the cumulative acute exposure of the population of Denmark to 25 organophosphorus and carbamate pesticide residues from the consumption of fruit, vegetables and cereals. The probabilistic approach was used in the assessments. Residue data obtained from the Danish monitoring programme carried out in the period 2004–2007, which included 6704 samples of fruit, vegetables and cereals, were used in the calculations. Food consumption data were obtained from the nationwide dietary survey conducted in 2000–2002. Contributions from 43 commodities were included in the calculations. We used the relative potency factor (RPF) approach to normalize the toxicity of the various organophosphorus and carbamate pesticides to the two index compounds chlorpyriphos and methamidophos. RPF values derived from the literature were used in the calculations. We calculated the cumulative acute exposure to 1.8% and 0.8% of the acute reference dose (ARfD) of 100 µg kg^–1 body weight (bw) day^–1 of chlorpyrifos as an index compound at the 99.9th percentile (P99.5) for children and adults, respectively. When we used methamidophos as the index compound, the cumulative acute intakes were calculated to 31.3% and 13.8% of the ARfD of 3 µg kg^–1 bw day^–1 at P99.9 for children and adults, respectively. With both index compounds, the greatest contributor to the cumulative acute exposure was apple. The results show that there is no cumulative acute risk for Danish consumers to acetylcholinesterase-inhibiting pesticides.     

Long-term dietary exposure to lead of the population of Jiangsu Province, China

Deterministic and probabilistic estimates of the chronic exposure to lead (Pb) for the inhabitants in Jiangsu Province, China, were performed. Pb contamination data were obtained from the national food contamination monitoring programme during 2001-2006 and 2600 samples from 38 commodities in Jiangsu were included. Food consumption data were from the national diet and nutrition survey conducted in 2002, including 3879 subjects aged 2-80 years and 185 children aged 2-6 years in Jiangsu. Contributions from 38 commodities were included in the calculations. Using the provisional tolerable weekly intakes (PTWI) divided into daily intakes (PTWI(d)) of 3.57 microg kg(-1) bw day(-1) in the risk assessment, exposures calculated by the deterministic approach for children and the general population were 77% and 43% of the PTWI(d), respectively, which were nearly similar to the mean intake calculation in the probabilistic approach. The percentage of people whose exposure level exceeded the PTWI(d) for children, the general population, urban population and rural population were 16%, 0.4%, 0.1%, and 0.5%, respectively. The 50th, 95th and 99th percentiles of Pb exposure for children were 2.6, 4.4 and 5.5 microg kg(-1) bw day(-1), respectively. Rice followed by wheat flour and bean products contributed most to the total Pb intake for both children and the general population. This study indicated that the Pb dietary exposure in Jiangsu Province, especially for children, would be a public health concern.     

Determination of trichothecenes in duplicate diets of young children by capillary gas chromatography with mass spectrometric detection.

Trichothecenes are mycotoxins produced by several fungal genera, mainly Fusarium species, that can contaminate a wide range of cereals used for human and animal consumption. They are associated with various adverse health effects in animals and humans such as feed refusal, vomiting and immunotoxic effects. A method based on capillary gas chromatography with mass spectrometric detection was developed and validated in-house for the determination of nine trichothecenes in duplicate diets of young children. The trichothecenes were extracted from the sample matrix by water/ethanol (90/10). The extracts were cleaned by means of ChemElut and Mycosep columns. The cleaned extracts were evaporated to dryness and derivatized to trimethylsilyl ethers at room temperature. The residues were dissolved in iso-octane and washed with water. The final extracts were analysed for trichothecenes by GC-MS. The response was linear in the range tested (1-10 microg kg(-1)). Recoveries for the trichothecenes were between 70 and 111%, with the exception of nivalenol, which had a low recovery (34%). The limit of quantification for all trichothecenes was below 0.4 microg kg(-1). Seventy-four food samples from young children collected by 74 respondents in a duplicate diet study were analysed for trichothecenes with the developed method. The mean levels of deoxynivalenol, nivalenol, HT-2 toxin and T-2 toxin were 5.8, 0.3, 0.3 and 0.1 microg kg(-1), respectively. Based on the individual results, dietary intake calculations were made. For deoxynivalenol, the tolerable daily intake of 1 microg kg(-1) body weight was exceeded by nine respondents. For the combined intake of T-2 and HT-2 toxin, the temporary tolerable daily intake of 0.06 microg kg(-1) body weight was exceeded by nine respondents.     

Estimated intake of intense sweeteners from non-alcoholic beverages in Denmark, 2005

In 2005, 76 out of 177 analysed samples of non-alcoholic beverages were found to contain the intense sweeteners cyclamate, acesulfame-K, aspartame, and saccharin. The content of cyclamate did not exceed the now permitted maximum level in the European Union of 250 mg l(-1) in soft drinks. The estimated intake of the sweeteners was calculated using the Danish Dietary Survey based on 3098 persons aged 1-80 years. The estimated intake with 90th percentiles of 0.7, 0.8 and 0.2 mg kg(-1) body weight day(-1) for acesulfame-K, aspartame, and saccharin, respectively, was much lower than the acceptable daily intake values of 15, 40, 7, and 2.5 mg kg(-1) body weight day(-1) for acesulfame-K, aspartame, and saccharin, respectively, and on the same level as in the similar investigation from 1999. In contrast to the 1999 investigation, the 90th percentile of the estimated cyclamate intake in 1-3 year olds with 3.7 mg kg(-1) body weight day(-1) was in 2005 lower than the acceptable daily intake of 7 mg kg(-1) body weight day(-1). However, the 99th percentile for 1-3 year olds with 7.4 mg kg(-1) body weight day(-1) still exceeded the acceptable daily intake slightly. The 90th percentile for the whole population with 0.9 mg kg(-1) body weight day(-1) was halved compared with 1999. The reduction in the European Union of the maximum permitted level for cyclamate from 400 to 250 mg l(-1) has brought the intake of cyclamate in small children down to well below the acceptable daily intake value.     

Simulation of deoxynivalenol intake from wheat consumption in Japan using the Monte Carlo method

The aim of this study was to evaluate the current advisory level in Japan for deoxynivalenol (DON) in foods. To this end, we estimated the intake of DON based on its presence in wheat using a probabilistic computer simulation method. Values for the concentration of DON in wheat were based on those reported in surveys of 638 wheat samples conducted from 2002 to 2004. Data regarding consumption of 108 wheat-based products according to age group were obtained from the 2002 Japan national survey on food consumption. Two data sets on the consumption of wheat-based products and contamination of DON in wheat were analysed using three DON regulatory scenarios: no regulation, 1100 μg kg(-1) and 2000 μg kg(-1). Because consumption distributions contained two peaks for each age category, it was assumed that two log-normal distributions for each age category were needed to achieve a better fit to the distribution models. The results of simulated DON intake using the Monte Carlo method showed that children aged 1-6 years have the highest DON intake. However, the 95th percentile of simulated intake of DON in each age group was below the provisional maximum tolerable daily intake (TDI) of 1 μg kg(-1) body weight using any regulation scenario. The 99th percentile of simulated DON intake in the 1-6-year-old group was greater than TDI at approximately 2 μg kg(-1) body weight. These results suggest that the current dietary intake of DON from wheat consumption does not exert a significant health effect, but we may need to reconsider the current regulation value for the 1-6-year-old age group. In addition, we may need a better method to fit the distribution to the log-normal distribution better.     

Estimated intake of intense sweeteners from non-alcoholic beverages in Denmark, 2005.

In 2005, 76 out of 177 analysed samples of non-alcoholic beverages were found to contain the intense sweeteners cyclamate, acesulfame-K, aspartame, and saccharin. The content of cyclamate did not exceed the now permitted maximum level in the European Union of 250 mg l(-1) in soft drinks. The estimated intake of the sweeteners was calculated using the Danish Dietary Survey based on 3098 persons aged 1-80 years. The estimated intake with 90th percentiles of 0.7, 0.8 and 0.2 mg kg(-1) body weight day(-1) for acesulfame-K, aspartame, and saccharin, respectively, was much lower than the acceptable daily intake values of 15, 40, 7, and 2.5 mg kg(-1) body weight day(-1) for acesulfame-K, aspartame, and saccharin, respectively, and on the same level as in the similar investigation from 1999. In contrast to the 1999 investigation, the 90th percentile of the estimated cyclamate intake in 1-3 year olds with 3.7 mg kg(-1) body weight day(-1) was in 2005 lower than the acceptable daily intake of 7 mg kg(-1) body weight day(-1). However, the 99th percentile for 1-3 year olds with 7.4 mg kg(-1) body weight day(-1) still exceeded the acceptable daily intake slightly. The 90th percentile for the whole population with 0.9 mg kg(-1) body weight day(-1) was halved compared with 1999. The reduction in the European Union of the maximum permitted level for cyclamate from 400 to 250 mg l(-1) has brought the intake of cyclamate in small children down to well below the acceptable daily intake value.     

Updated profile of aflatoxin and Aspergillus section Flavi contamination in rice and its byproducts from the Philippines.

Our goal was to develop an updated profile of aflatoxin (AF) and AF-producing fungi contamination in rice and its byproducts from the Philippines. The total AF levels in 78 samples of polished and brown rice, determined by an immunoaffinity column clean-up method coupled with HPLC (detection limit: 25 ng/kg), ranged from <0.025-2.7 microg/kg (mean of positive samples: 0.37 microg/kg) and 0.03-8.7 microg/kg (mean of positive samples: 2.7 microg/kg), respectively. The incidence (% of positive samples) of AF in polished and brown rice were 94% and 100%, respectively. The AF levels in polished rice imported from Thailand and Vietnam were approximately 20% of the levels found in locally produced polished rice. AF levels decreased as the rice progressed through the various stages in milling. Fungi recovered include toxigenic Aspergillus flavus and A. parasiticus with an incidence ranging from 14% in rice bran to 78% in rough rice and producing <0.025-6200 microg/kg total AF in in vitro cultures on rice. All samples of rice bran and rice hull contained AF at levels ranging from 0.27-11 microg/kg. The estimated potential daily intake of AFB(1) from rice is between 0.1 and 7.5 ng/kg of body weight/day, the mean of which is 1.0 ng representing 9.1-5.3 times the estimated tolerable daily intake for AFB(1) reported to date for Asia. Thus, Filipinos have a potentially high risk of exposure to AF that can be easily controlled through proper post-harvest handling and storage of rice and its byproducts.     

Risk assessment for furan contamination through the food chain in Belgian children

Young, old, pregnant and immuno-compromised persons are of great concern for risk assessors as they represent the sub-populations most at risk. The present paper focuses on risk assessment linked to furan exposure in children. Only the Belgian population was considered because individual contamination and consumption data that are required for accurate risk assessment were available for Belgian children only. Two risk assessment approaches, the so-called deterministic and probabilistic, were applied and the results were compared for the estimation of daily intake. A significant difference between the average Estimated Daily Intake (EDI) was underlined between the deterministic (419 ng?kg(-1) body weight (bw) day(-1)) and the probabilistic (583 ng?kg(-1) bw day(-1)) approaches, which results from the mathematical treatment of the null consumption and contamination data. The risk was characterised by two ways: (1) the classical approach by comparison of the EDI to a reference dose (RfD(chronic-oral)) and (2) the most recent approach, namely the Margin of Exposure (MoE) approach. Both reached similar conclusions: the risk level is not of a major concern, but is neither negligible. In the first approach, only 2.7 or 6.6% (respectively in the deterministic and in the probabilistic way) of the studied population presented an EDI above the RfD(chronic-oral). In the second approach, the percentage of children displaying a MoE above 10,000 and below 100 is 3-0% and 20-0.01% in the deterministic and probabilistic modes, respectively. In addition, children were compared to adults and significant differences between the contamination patterns were highlighted. While major contamination was linked to coffee consumption in adults (55%), no item predominantly contributed to the contamination in children. The most important were soups (19%), dairy products (17%), pasta and rice (11%), fruit and potatoes (9% each).     

Occurrence of patulin in conventional and organic fruit products in Italy and subsequent exposure assessment.

The occurrence of patulin was investigated in 100 conventional and 69 organic fruity foodstuffs samples commercially available in Italy by using an HPLC method with a limit of quantification of 0.5 microg kg(-1). Patulin was detected in 26 (26%) conventional and 31 (45%) organic products with a significantly higher (p<0.01) mean concentration in the organic products (4.78 vs. 1.15 microg kg(-1)). Mean patulin concentrations in conventional apple juices, pear juices, other juices and fruits purees were 3.14, 0.22, 0.19, 0.11 microg kg(-1), respectively, and 7.11, 11.46, 2.10, 0.18 microg kg(-1) in the relevant organic products. Four samples of juices (one conventional and two organic apple, and one organic pear) contained patulin at concentrations above the limit of 50 microg kg(-1), four at concentrations between 10 and 25 microg kg(-1), and the remaining ones below 10 microg kg(-1). Patulin was detected (<1 microg kg(-1)) in only three of the 23 fruity baby food samples tested (homogenized fruits, 11 conventional and 12 organic). Based on the available data on Italian intakes of fruit juices, the estimated daily intakes of patulin, were 0.38 and 1.57 ng kg(-1) body weight (bw) from conventional and organic products, respectively. Estimated daily intakes of patulin for children were higher, 3.41 ng kg(-1) bw from conventional and 14.17 ng kg(-1) bw from organic products, but largely below the provisional maximum tolerable daily intake (PMTDI) of 400 ng kg(-1) bw. Patulin was also found in two samples of organic apple vinegar (<5 microg kg(-1)) and in fresh apples with rotten spots (12 out of 24 samples) with maximum levels at 16,402 and 44,572 microg kg(-1) for conventional and organic apples, respectively.     

Aflatoxin B(1) contamination of parboiled rice samples collected from different states of India: A multi-centre study.

Under a multi-centre study conducted by the Indian Council of Medical Research, 1,511 samples of parboiled rice were collected from rural and urban areas of 11 states representing different geographical regions of India. These samples were analysed for contamination with aflatoxin B(1.) The presence of aflatoxin B(1) at levels=5 microg g(-1) was found in 38.5% of the total number of samples of the parboiled rice. About 17% of the total samples showed the presence of aflatoxin B(1) above the Indian regulatory limit of 30 microg kg(-1). No statistically significant difference in percentage of samples contaminated with >30 microg kg(-1) was observed between pooled rural (19.4%) and urban (14.5%) data. A median value of 15 microg kg(-1) of aflatoxin B(1) was observed in samples from Assam, Bihar and Tripura. In all other states surveyed the median value was <5 microg?kg(-1).     

Probabilistic intake assessment and body burden estimation of dioxin-like substances in background conditions and during a short food contamination episode.

The objective was to perform a dioxin body burden estimate based on a probabilistic intake assessment of PCDDs, PCDFs and dioxin-like PCBs because of the so-called 1999 'Belgian dioxin incident'. Monte Carlo simulation techniques were used to combine detailed 7-day food intake data on the individual level from a sample of 14-18-year-old adolescents with 'background' and 'incident-related' food contamination data. In background conditions, 3% of the adolescents had an intake <1 pg TEQ kg(-1) bw day(-1), while 85% had <4 pg TEQ kg(-1) bw day(-1). Milk and other dairy products were the basic source of dioxin-like contaminants, while fish constituted the main source at the higher percentiles of intake. During the dioxin incident, the estimated median dioxin intake showed a moderate increase. At the 99th percentile, the highest intake level, and the 95% upper bound uncertainty level, peak body burden-23.73 ng TEQ kg(-1) bw-remained below body burdens that in the experimental animal or in man are accompanied by a population-based observable increase in the incidence of adverse effects. The 1999 Belgian dioxin incident most likely did not affect public health in Belgium in a measurable way, although exceptions remain possible on the individual level.     

Calculation of the dietary exposure of Chinese consumers to acephate residues using deterministic and probabilistic approaches

This paper compares the exposure for the Chinese populations and sub-groups to acephate, a widely applied organophosphorus pesticide, using deterministic and probabilistic approaches. Acephate residue data were obtained from the national food contamination monitoring program 2001-2006, collected by multi-stage stratified sampling and with a detection rate of 3.3%. Food consumption data were gathered from the national diet and nutrition survey conducted in 2002 over three consecutive days by the 24-h recall method, and included 22,563 families or 65,886 consumers aged 2-100 years. For point estimate, it was evident that exposures were higher than the acute reference dose (ARfD) in many cases. For the probabilistic approach, the P99.9 exposures for the general population and children accounted for 11.88 and 24.15% of the ARfD, respectively, in acute intake calculations and 52.86 and 68.75%, respectively, of the acceptable daily intake (ADI) in chronic intake calculations. The exposure level of rural people was higher than urban dwellers, and vegetables contributed most to acephate intake.     

Predicted intake of trace elements and minerals via household drinking water by 6-year-old children from Krakow, Poland. Part 3: aluminium.

In order to assess aluminium intake via drinking water by children, approximately 400 households in urban, peripheral, and rural areas were investigated. The study comprised about 200 children (5-7 years old) in the period between 2000 and 2001. The samples of drinking water were collected by a double sampling method (morning and evening). Aluminium was measured by graphite furnace-atomic absorption spectroscopy (GF-AAS). Geometric means (microg l(-1), confidence interval) were for evening samples: urban 72.5 (13.2-398), peripheral 6.3 (0.5-86.7), and rural 16.6 (0.5-593). For most households the aluminium concentration in the morning samples was lowered by about 40% due to deposition of aluminium-containing compounds during standing overnight. These deposits can be later taken up into the water. The European Commission aluminium limit of 200 microg l(-1) for drinking water was exceeded for 7.7, 0 and 13.2% of households from urban, peripheral, and rural areas, respectively. The predicted contribution of drinking water to aluminium intake by 6-year-old children was 3.81 microg day(-1) kg body weight(-1) or 2.7% of the provisional tolerable weakly intake (PTWI. 1 mg kg(-1) body weight) for urban sites and less for the others. For those cases exceeding the aluminium limit, the predicted aluminium intake via water consumption was 18.4-42.1 microg day(-1) kg body weight(-1) and contributed 12.8-29.5% of the provisional tolerable weakly intake. In urban areas the aluminium concentration was enhanced due to water treatment; while in rural sites it was due to contamination from cement-made wells. The high prevalence of cement wells in rural areas suggests that drinking water from individual sources should be included in a safety control system. The quality of materials for the construction of wells and containers for drinking water storage should be also improved. In order to limit aluminium intake from drinking water, this study also supports the suggestion of discarding overnight standing water before it is taken for consumption, especially for use by children.     

Relationship between total mercury concentration and fish size in two pelagic fish species: implications for consumer health

Total mercury concentrations were determined in different size classes of two pelagic fish species of great commercial importance, horse mackerel (Trachurus trachurus) and Mediterranean horse mackerel (Trachurus mediterraneus), to evaluate the relationship between total mercury concentration and fish size and to determine whether any differences might affect the quantitative assessment of mercury exposure for consumers. Mercury concentrations in horse mackerel and in Mediterranean horse mackerel were between 0.16 and 2.41 microg g(-1) of weight wet (mean, 0.68 microg g(-1)) and between 0.09 and 1.62 microg g(-1) (mean, 0.51 microg g(-1)), respectively. The regression curves revealed a significant relationship between mercury concentration and fish size (length and weight) for both species. Concentrations exceeding the proposed limit for human consumption were observed in 33.3% of the samples of both species and were associated with larger specimens. The consumption of the larger specimens could lead to an increase in mercury exposure for consumers. Estimated weekly intakes, calculated on the basis of concentrations relative to each size class, revealed a high exposure associated with the consumption of fish larger than 30 cm (horse mackerel, 11.63 to 20.16 microg/kg of body weight; Mediterranean horse mackerel, 5.86 to 13.55 microg/kg of body weight). An understanding of the factors leading to an increase in mercury exposure can help consumers make informed decisions about eating fish.     

Quantitative Risk Assessment for Formalin Treatment in Fish Preservation: Food Safety Concern in Local Market of Bangladesh

In Bangladesh, fishes are adulterated by hazardous chemicals at different steps from farm to consumers. Formalin (FA) is reported to be frequently added as preservative either by dipping or spraying to the fresh fishes by the fish traders while transporting to domestic marketing chain to prevent spoilage and extend shelf life. Thus, the objective of the present study was toconduct quantitative risk assessment (QRA) for formalin treated fish in Bangladesh. The probabilistic QRA of formalin treated fish was performed based on available secondary data. Available data on concentration of formalin in fish, daily fish consumption by the consumer and their body weight were used to estimate the risk of residual formalin to the consumers. Based on the data, three different scenarios (average consumption, two and four times of average consumption considered as scenarios 1, 2 and 3, respectively) were used for exposure analysis using @Risk program version 6.0.FA concentration in consumedfresh and cooked (boiling) fish was 5.34x10^-02 and 2.340x10^-02 (mg/kg bw/day), respectively and national average fish consumption was 200 g/day. QRA reveals that FA intake under scenario1 and 2 was lower than acceptable daily intake (ADI 0.2 mg/kg bw/day set by the United States Environmental Protection Agency) thus lower risk observed for both fresh and cooked fish. However, scenario 3 revealed that 0.01% population was at risk (FA intake 0.21 mg/kg bw/day higher than ADI) upon the fresh fish consumption, where cooked fish (FA 9.38x10^-02 mg/kg bw/day) consumer remains safe at the same scenario. The result confirmed that cooking has significant effect to reduction of formalin. Therefore, probabilistic quantitative risk assessment of formalin treated fish could provide important risk information to the risk manager (government), whether the population is at risk or not? The result could be applied to establish effective risk management strategy in Bangladesh.     

Predicted intake of trace elements and minerals via household drinking water by 6-year-old children from Krakow, Poland. Part 3: aluminium

In order to assess aluminium intake via drinking water by children, approximately 400 households in urban, peripheral, and rural areas were investigated. The study comprised about 200 children (5-7 years old) in the period between 2000 and 2001. The samples of drinking water were collected by a double sampling method (morning and evening). Aluminium was measured by graphite furnace-atomic absorption spectroscopy (GF-AAS). Geometric means (microg l(-1), confidence interval) were for evening samples: urban 72.5 (13.2-398), peripheral 6.3 (0.5-86.7), and rural 16.6 (0.5-593). For most households the aluminium concentration in the morning samples was lowered by about 40% due to deposition of aluminium-containing compounds during standing overnight. These deposits can be later taken up into the water. The European Commission aluminium limit of 200 microg l(-1) for drinking water was exceeded for 7.7, 0 and 13.2% of households from urban, peripheral, and rural areas, respectively. The predicted contribution of drinking water to aluminium intake by 6-year-old children was 3.81 microg day(-1) kg body weight(-1) or 2.7% of the provisional tolerable weakly intake (PTWI. 1 mg kg(-1) body weight) for urban sites and less for the others. For those cases exceeding the aluminium limit, the predicted aluminium intake via water consumption was 18.4-42.1 microg day(-1) kg body weight(-1) and contributed 12.8-29.5% of the provisional tolerable weakly intake. In urban areas the aluminium concentration was enhanced due to water treatment; while in rural sites it was due to contamination from cement-made wells. The high prevalence of cement wells in rural areas suggests that drinking water from individual sources should be included in a safety control system. The quality of materials for the construction of wells and containers for drinking water storage should be also improved. In order to limit aluminium intake from drinking water, this study also supports the suggestion of discarding overnight standing water before it is taken for consumption, especially for use by children.     

Avian toxicity reference values for perfluorooctane sulfonate

Toxicity reference values (TRVs) and predicted no effect concentrations (PNECs) were derived for perfluorooctane sulfonate (PFOS) based on the characteristics of a top avian predator. On the basis of the protective assumptions used in this assessment, the benchmarks are protective of avian populations and were based on acute and chronic dietary exposures of northern bobwhite quail and mallard. Toxicological endpoints included mortality, growth, feed consumption, and histopathology. Reproductive endpoints included egg production, fertility, hatchability and survival, and growth of offspring. On the basis of the U. S. Environmental Protection Agency Great Lakes Initiative methodology, and a lowest observable adverse effect concentration (LOAEC) of 10 mg PFOS kg(-1) feed, an uncertainty factor of 36 was derived. The TRV based on PFOS dietary intake was 0.021 mg PFOS kg(-1) body weight day(-1), while for serum, liver, and egg, TRVs were 1.7 microg PFOS mL(-1), 0.6 microg PFOS g(-1) wet weight, and 1.7 microg PFOS mL(-1), respectively. On the basis of the European Commission methodology, a correction factor of 2 (for lowest observed effect level to no observable effect level) and an assessment factor of 30, for a total adjustment of 60, were used to derive PNECs. PNECs based on dietary, mean serum, liver, and egg PFOS concentrations were 0.013 mg PFOS kg(-1) body weight day(-1), 1.0 microg PFOS mL(-1), 0.35 microg PFOS g(-1) wet weight, and 1.0 microg PFOS mL(-1), respectively.     

Nitrite and nitrate content in meat products and estimated intake in Denmark from 1998 to 2006

The content of nitrite and nitrate in cured meat products has been monitored in Denmark seven times between 1995 and 2006. The maximum permitted added amounts of sodium nitrite in Denmark (60 mg kg(-1) for most products up to 150 mg kg(-1) for special products) have not been exceeded, except for a few samples back in 2002. The intake, mean and intake distribution of sodium nitrite have been calculated from 1998 to 2006 with data from the Danish dietary survey conducted in 2000-02 on Danes from four to 75 years of age. The amounts used by industry have been relatively stable through the whole period with levels varying between 6 and 20 mg sodium nitrite kg(-1) with sausages, meat for open sandwiches and salami-type sausages being the greatest contributors. The mean intake of sodium nitrate was around 1 mg day(-1), which is very low compared with the total intake of 61 mg day(-1). The mean intake of sodium nitrite was 0.017 and 0.014, 0.009 and 0.008, and 0.007 and 0.003 mg kg(-1) body weight day(-1) for men and women in the age groups 4-5, 6-14 and 15-75 years, respectively, which was much lower than the acceptable daily intake (ADI) of 0.09 mg kg(-1) body weight day(-1). The 99th percentile for the group of 4-year-olds was 0.107 and 0.123 mg kg(-1) body weight day(-1) for boys and girls, respectively, and the 95th percentile was 0.057 and 0.073 mg kg(-1) body weight day(-1) for boys and girls, respectively, highest for the girls. With fewer than 100 boys and girls in the 4-5-year age group, only very few persons were responsible for the high intake. The conversion of nitrate to nitrite in the saliva and the degradation of nitrite during production and storage must also be considered when evaluating the intake of nitrite.