ABSTRACT
Request from the Norwegian Food Safety Authority The Norwegian Food Safety Authority (NFSA) requested the Norwegian Scientific Committee for Food Safety (VKM) to assess whether Norwegians in general or subgroups in the population could be expected to have different dietary exposure to acrylamide than reported for other European population groups, and if found to be different to calculate their exposure. Furthermore, VKM was asked to identify food categories with a high potential to increase acrylamide exposure; both for the whole population and for specific groups. Finally, VKM was asked to characterise the risk of acrylamide exposure to the Norwegian population compared to the rest of the European population. The Norwegian Food Safety Authority intends to use this risk assessment as a basis for the Norwegian contribution to the ongoing legislative work in the EU and to consider the necessity to adjust the existing national dietary advices or to issue new ones. How VKM has addressed the request VKM appointed a working group consisting of members of the Panel on Contaminants to answer the request. The Panel on Contaminants has reviewed and revised the draft prepared by the working group and finally approved the risk assessment on dietary acrylamide exposure in the Norwegian population. What acrylamide is and its toxicity to humans Acrylamide is a water-soluble organic chemical formed in carbohydrate-rich foods from naturally present carbohydrates and amino acids during cooking or other heat processing at temperatures above 120°C. Acrylamide is a widely used industrial chemical and is also formed in tobacco smoke. Acrylamide is known to be neurotoxic in humans and is classified as a probable human carcinogen. Concerns about exposure to acrylamide in the general population arose in 2002 when it was discovered in heat-treated foods. Dietary acrylamide exposure in Europe and Norway Dietary acrylamide exposure has been assessed by combining food consumption data and acrylamide concentration data and by biological markers of exposure both in Norway and different European countries. In the EFSA 2015 Scientific Opinion on acrylamide in food, chronic dietary exposure was calculated for 61,338 individuals from 28 surveys and 17 different European countries covering the following age groups: infants (<1 year old), toddlers (≥1 year to <3 years old), other children (≥3 years to <10 years old), adolescents (≥10 years to <18 years old), adults (≥18 years to <65 years old), elderly (≥65 years to <75 years old) and very elderly (≥75 years old). The estimation of human exposure to acrylamide revealed that infants, toddlers and other children were the most exposed groups, but EFSA concluded that dietary acrylamide represents a health concern for all age groups. In previous Norwegian studies reporting dietary acrylamide exposure, the mean and median exposure in adolescents and adults were in the range of 0.3-0.5 μg/kg bw per day. These estimates are in the same range as the mean daily exposures estimated by EFSA for adolescents (0.4-0.9 μg/kg bw) and adults (0.4-0.5 μg/kg bw). Taking into consideration the results from previous exposure estimates and knowledge about food consumption patterns in recent consumption surveys in Norway, VKM concludes that Norwegian adults, adolescents and children older than three years of age are not likely to have a different exposure to acrylamide than corresponding age groups in other European countries. VKM therefore decided not to perform a new exposure assessment in these age groups. No previous studies in Norway have assessed acrylamide exposure in infants and children less than three years of age. Information from national and European dietary surveys shows that Norwegian 1-year-olds, but not 2-year-olds, have higher consumption of infant porridge than other European toddlers. VKM therefore decided to conduct a full exposure estimate in 1-year-old toddlers. The comparison of data on acrylamide occurrence in food reported by EFSA (2015) and in foods sampled in Norway showed that acrylamide concentrations in the main food categories do not differ essentially, with the exception of three categories. The category “Potato crisps and snacks” has higher acrylamide concentrations in Norwegian samples than in those reported by EFSA, while the categories “Baby foods, other than cereal-based” and “Processed cereal-based baby food” (i.e. infant porridge) have lower concentrations in Norwegian samples than in those reported by EFSA. VKM considered that Norwegian analytical values were sufficient for exposure calculations if the concentrations were analysed in 16 samples or more. Infant porridge had 52 analysed samples and VKM considered that the brands sampled are representative for infant porridge on the Norwegian market. VKM calculated acrylamide exposure based on food consumption in Norwegian 1-year-olds by two approaches: one using EFSA concentration data only; and the other using Norwegian concentration data for food categories including 16 samples or more, and EFSA data for the remaining categories. Both approaches resulted in acrylamide exposures within the exposure range for toddlers reported by EFSA (2015). When using EFSA concentration data only the calculated daily exposure (mean: 1.6 μg/kg bw and P95: 3.2 μg/kg bw) is in the upper range calculated by EFSA for toddlers (mean range: 0.9-1.9 μg/kg bw, P95 range: 1.2-3.4 μg/kg bw). When using Norwegian concentration data for food categories including 16 Norwegian samples or more and EFSA data for the remaining categories, the calculated daily exposure (mean: 0.9 μg/kg bw, P95: 1.6 μg/kg bw) is in the lower range of what EFSA has calculated for toddlers. The dietary exposure for acrylamide in Norwegian 1-year-olds is within the same range as reported by EFSA for European toddlers. Although the acrylamide-concentration was lower in infant porridge (i.e. “Processed cereal-based baby food”) sampled in Norway than in those reported by EFSA, Norwegian 1-year-olds have higher consumption of infant porridge than European toddlers. In addition to infant porridge, soft bread is a major source of acrylamide in Norwegian 1-year-olds. Food categories with high potential to increase acrylamide exposure Baby food and soft bread contributed most to acrylamide exposure in the 1-year-olds, while food items contributing the most to acrylamide exposure in adults are fried potato products, coffee, biscuits, crackers and crisp breads, and soft bread. Previous Norwegian studies and EFSA (2015) showed that in all populations groups except toddlers, ‘fried potato products’ is a food group with high potential to increase acrylamide exposure. Acrylamide is also contributed by food items commonly consumed such as coffee and bread, and this is of concern in Norway as well as in the rest of Europe. The EFSA risk assessment included exposure scenarios addressing the potential impact of home-cooking habits, locations of consumption, and preferences for particular food products. These scenarios showed that food preparation, and particularly conditions of potato frying, resulted in large variations and a possible increase of acrylamide exposure by as much as 80%. VKM considers that these scenarios carried out by EFSA are equally relevant for the Norwegian population. The temperature and browning of fried potato products will have a considerable impact on the exposure to acrylamide. VKM calculated three simplified scenarios to illustrate the influence of consumption of particular food items on acrylamide exposure. These scenarios confirmed that potato crisps, French Fries and coffee are food items with high potential to increase acrylamide exposure. Risk characterisation of dietary acrylamide exposure in Norway VKM used the same reference points as EFSA (2015), and calculated Margin of Exposures (MOEs) for assessing health risk. MOE is the ratio between a reference value and the estimated dietary exposure. The MOE approach provides an indication of the level of safety but it does not quantify the risk as such. For non-neoplastic effects, EFSA used a BMDL10 value of 0.43 mg/kg bw/day as the reference point based on animal studies of neurotoxicity, and considered a substance-specific MOE of 125 or above as a sufficient safety margin for no health concern. For neoplastic effects, EFSA used a BMDL10 value of 0.17 mg/kg bw/day as the reference point based on animal studies, and taking into account overall uncertainties in the interpretation, EFSA concluded that a MOE of 10 000 or higher would be of low concern for public health. The EFSA risk assessment concluded that the MOEs for non-neoplastic effects were above 125 for all age groups indicating no health concern, whereas the MOEs for non-neoplastic effects were substantially lower than 10 000, indicating a health concern for all age groups. The dietary acrylamide exposure in Norwegian adolescent and adults reported in previous studies were within the range calculated by EFSA for these age groups. VKM therefore concludes that the resulting MOEs for non-neoplastic and neoplastic effects of acrylamide for adolescent and adults will be similar to those calculated by EFSA. VKM calculated acrylamide exposure based on food consumption in Norwegian 1-year-olds by two approaches: one using EFSA concentration data only; and the other using Norwegian concentration data for food categories including 16 samples or more, and EFSA data for the remaining categories. Both approaches resulted in comparable MOEs. For both non-neoplastic and neoplastic effects, MOEs for 1-year-olds were similar to those reported in EFSA 2015. For non-neoplastic effects of dietary acrylamide exposure, VKM reached the same conclusion as EFSA, which is that the MOEs across all age groups indicate no health concern. For neoplastic effects of dietary acrylamide exposure, VKM reached the same conclusion as EFSA, whi
ABSTRACT
Request from the Norwegian Food Safety Authority (NFSA): The Norwegian Food Safety Authority requested the Norwegian Scientific Committee for Food Safety (VKM) to evaluate whether Norwegians in general or subgroups in the population could be expected to have different dietary exposure to cadmium than reported for other European population groups. Furthermore, VKM was asked to assess the potential health risk of cadmium exposure from brown meat of crabs and to identify how much crab can be eaten by children and adults without exceedance of the tolerable intake for cadmium. Finally, VKM was asked to identify other particular food items which would lead to an added cadmium exposure in Norway. The Norwegian Food Safety Authority intends to use the risk assessment as a basis for the Norwegian contribution to the ongoing legislative work in the EU and to consider the necessity to adjust the existing national dietary advices or to issue new ones. How VKM has Addressed the Request: VKM appointed a working group consisting of members of the Panel on Contaminants to answer the request. The Panel on Contaminants has reviewed and revised the draft prepared by the working group and finally approved the risk assessment on dietary cadmium intake in the Norwegian population. What Cadmium is and Its Toxicity to Humans: Cadmium (Cd) is a heavy metal found as an environmental contaminant, both through natural occurrence and from industrial and agricultural sources. Humans are exposed to cadmium by food, water and air, with food as the most important source in non-smokers. Cadmium accumulates especially in the kidneys and in liver. The amount of cadmium in the body increases continuously during life until the age of about 6070 years, from which it levels off. The most well characterised chronic toxic effects resulting from cadmium exposure are on kidneys and bones. The tolerable weekly intake (TWI) of cadmium was in 2009 reduced by EFSA from 7 to 2.5 μg /kg body weight (bw). The new TWI established was based on human studies on the dose-response relationship between concentration of cadmium in urine and kidney function. Severe cadmium-induced damage in cells in the proximal kidney tubules is considered to be irreversible and results in the progressive deterioration of renal function, even after cessation of exposure. Long-term exceedance of the TWI is of concern as it can increase the risk of developing kidney disease in the population. Keeping the exposure below the TWI will ensure that the cadmium concentrations in the kidneys will not reach a critical level for reduced kidney function. Dietary Intakes in Europe and Norway, and Major Dietary Cadmium Sources: In 2012, EFSA estimated that the mean cadmium exposure from food in Europe was close to the TWI and exceeded the TWI in some population groups, like toddlers and other children. Previous exposure assessments in Europe and Scandinavia, including Norway, clearly show that cereal based food and root vegetables, particular potatoes, are the major dietary cadmium sources in the general population. These are, however, not the food groups with the highest cadmium concentrations. The highest concentrations have been found in offal, bivalve molluscs and crustaceans (e.g. crabs), and previous exposure assessments have shown that high consumption of such food can be associated with high cadmium exposure at the individual level. There is large variation at the individual level regarding consumption of particular food items (e.g. crab brown meat) that can be important contributors to cadmium exposure in addition to the exposure from the regular diet. VKM has compiled the available Norwegian data on cadmium concentrations in food, mainly from 2006 and onwards. Comparison of Norwegian and European occurrence data shows that the cadmium concentrations for the food categories and items in the two datasets are within a similar range. The exceptions are fish filet and fish products (dishes based on minced fish meat), in which the mean cadmium concentrations were higher in products on the European market than in fish from Norway. VKM has evaluated if there are national factors (geological factors, self-sufficiency rate, national occurrence data and food consumption habits) that would indicate that exposure in Norway is different from the rest of Europe. VKM has also evaluated available national and European data on concentrations of cadmium in blood and urine in relation to estimated dietary intakes. VKM concludes that it can be expected that cadmium exposure among adults in Norway is within the range previously identified by EFSA, and close to the exposure estimated for Sweden. VKM is of the opinion that long-term cadmium exposure above the TWI as result from the regular diet in adults is unlikely in Norway, but that exceedance might occur from the additional consumption of food items with high cadmium concentrations, in particular brown meat of crabs. In dietary exposure estimates from EFSA, toddlers and other children have mean cadmium exposure exceeding the TWI, due to their higher food consumption relative to the body weight. Based on this, VKM expects that the mean dietary cadmium exposure in toddlers and children may exceed the TWI also in Norway. Risk from Cadmium Intake from Particular Foods in Norway: Based on the mean concentrations of cadmium, VKM identified fish liver, bivalve molluscs and offal in addition to brown crab meat as particular food items that potentially can lead to added cadmium exposure in Norway. Since these particular food items are mainly eaten on a seasonal or non-regular basis, it was stipulated that the associated cadmium exposure would come in addition to the mean exposure from regularly eaten food. In scenario exposure assessments, VKM calculated how much crabs/fish liver that could be consumed by adults and adolescents in addition to the regular diet without exceeding the TWI. The mean dietary exposures in adults and adolescents calculated by EFSA in 2012 were used as the mean exposures from regularly eaten food. Since cadmium accumulates in the kidneys over time (decades), VKM is of the opinion that a short-term exceedance of the TWI (for some weeks or a few months) will not lead to adverse effects in the kidneys as long as the long-term exposure (for several months and years) is below the TWI. VKM therefore considers that the cadmium exposure from particular food items can be averaged over longer time-periods (for months and up to one year) than a week. Crabs and fish liver: The edible crab Cancer pagurus is found all along the Norwegian coast up to Vesterålen, whereas further north the occurrence is infrequent. Brown meat from crabs contains much higher concentrations of cadmium than any other food item commonly consumed in Norway, and has approximately 14 to 20-fold higher concentration of cadmium than white crab meat. The cadmium concentration in fish liver is about two-fold higher than in white meat from crabs caught south of Saltenfjorden. A large part of the Norwegian adult population report consumption of crabs or fish liver at least a few times a year, while a small fraction consume these particular food items more frequently. Consumption of brown meat from crabs and fish liver is, however, not common in most European regions and therefore not covered by the exposure estimates performed by EFSA. The dietary assessment method used in the recent Norwegian national food consumption survey in adults (two times 24h dietary recall) does not supply reliable information about consumption of foods that are not eaten on a daily basis. In order to estimate cadmium exposure from rarely eaten foods, VKM has calculated scenarios for the exposure to cadmium from consumption of crabs and fish liver. Scallops, oysters and offal: The cadmium concentrations in scallops and oysters are 2-3 fold higher than in white meat from crabs caught south of Saltenfjorden. Offal, in particular offal from game and sheep, contains much higher cadmium concentrations than the meat from the same species. However, consumption of offal, including offal from game, and bivalve molluscs is generally low in Norway, although high consumption in some population groups cannot be excluded. In contrast to Norway, consumption of offal and bivalve molluscs is more common in some European regions, and is therefore covered by the exposure estimates performed by EFSA. Scenarios for Cadmium Exposure from Crab or Fish Liver Consumption: Crabs and filled crab shells: Because of high cadmium levels in edible crabs (Cancer pagurus) north of Saltenfjorden up to Vesterålen, Norwegian Food Safety Authority has issued advice to avoid consumption of all parts of crabs caught in this area. The scenarios presented below are valid only for meat of crabs caught south of Saltenfjorden. Whole crabs contain a higher percentage of brown meat than commercially available filled crab shells, and this was taken into account in the scenarios. Scenarios of cadmium exposure from crab consumption indicate that adults can eat approximately one whole crab or two filled crab shells per month in addition to regular food without exceeding the TWI. Averaged over a year, this corresponds to 13.5 whole crabs or approximately 25 filled crab shells. If adults only eat white crab meat, they can consume white meat from approximately nine crabs per week, which corresponds to white meat from approximately 468 crabs per year. Adolescents can eat as little as approximately 0.3 whole crabs or 0.6 filled crab shells per month in addition to regular food without exceeding the TWI. Averaged over a year, this corresponds to 3-4 whole crabs per year or approximately 7 filled crab shells. If adolescents only eat white crab meat, they can consume white meat from about 2.5 crabs per week, which corresponds to white meat from approximately 129 crabs per year. Since a higher crab consumption than the acceptable range calculated in the scenarios ha