Chloroform in food samples from 2014 Canadian total diet study: occurrence and dietary exposure.

Chloroform or trichloromethane is one of the trihalomethanes formed during disinfection of water with chlorine, and residues of chloroform can be detected in foods and food products due to the use of chlorinated drinking water and disinfecting food processing equipment with chlorine-based disinfectants. In this study, chloroform was detected in 37 (or 23%) of the 159 composite food samples from the 2014 Canadian Total Diet Study, but was not detected in cereals, fruits, fast foods, and most of the meat samples. Chloroform was detected in almost all 14 composite samples of dairy products, with the highest level (58 ng/g) observed in butter, followed by cream (26 ng/g), and cheese (12-21 ng/g). Chloroform was detected in tap water (23 and 29 ng/g) and most of the beverage samples, but concentrations were lower than those reported in other studies possibly due to evaporation during the preparation of the composite samples. Dietary exposures to chloroform are higher for younger age groups (0.51-1.41 µg/kg body weight/day) than for adults (0.25-0.42 µg/kg body weight/day). Drinking water contributed most to daily intakes for all age groups, accounting for between 62% and 86% of the total chloroform dietary intakes.

Trends of bisphenol A occurrence in canned food products from 2008-2020.

It is known that the industry already abandoned the use of bisphenol A (BPA)-based epoxy resins as internal coatings for some canned food products (e.g. infant formula, soups). The presence of bisphenol A (BPA) in foods has also been extensively investigated, especially since late 2000. However, information on temporal trends of BPA occurrence in foods is very limited. It is not clear if BPA-based epoxy resins are still being used in internal coating for many other canned foods and if the overall exposure to BPA through consumption of canned foods has significantly decreased. As part of the Canadian total diet study (TDS) program, we have been analysing food samples for BPA since 2008. In this study, results of BPA in samples of different composite canned foods from 2008-2020 TDS were reported. Clear temporal trends were observed for canned fish and soups, with BPA levels being significantly reduced since 2014 for canned fish products and 2017 for canned soups. Temporal trends were not observed for canned evaporated milk, luncheon meats, and vegetables, with even the highest levels of BPA being detected in recent samples for evaporated milk (57 ng/g), luncheon meats (56 ng/g), and baked beans (103 ng/g). This seems to indicate that BPA-based epoxy resins are still being used in the internal coatings for these canned foods products. Thus, analysis of canned food samples for BPA should be continued for exposure assessment.

Temporal trend of bisphenol S occurrence in meat samples from 2008-2020 Canadian total diet study.

In our previous study, bisphenol S (BPS) was detected unexpectedly and at high levels in meat samples from 2016 and 2020 Canadian total diet study (TDS). In this study, samples of meat and meat products from 2008-2015 and 2017-2019 TDS were also analysed to investigate the consistency of BPS occurrence in meat and identify possible trends and provide some information on the potential sources for BPS in meat. BPS was detected again with the highest levels observed in samples of fresh pork (105 ng/g) and veal cutlets (140 ng/g) from the 2008 TDS. This indicates that the occurrence of BPS in meat is not a recent phenomenon but rather an existing one since 2008 or even earlier. BPS concentrations in meat samples from the 2008 to 2020 TDS varied significantly, e.g. 1.2-118 ng/g in roast beef, 1.8-140 ng/g in veal cutlets, but no trend was observed. The lack of trend for BPS over the period of 13 years (2008-2020) does not support the speculation that BPS is being used to replace BPA in food packaging, and sources other than food packaging may be possible and should be investigated for BPS.

Bisphenol S in individual and composite meat and meat products and implication for its sources.

In this study, the occurrence of bisphenol S (BPS) in the meat and meat products from a recent Canadian Total Diet Study (TDS) was investigated in more detail. In addition to their composite samples, the individual raw meat and meat products were also analysed for BPS to investigate the variations of BPS levels and provide some information on the potential sources for BPS in meat. BPS was detected in all the 11 composite samples of different meat and meat products, with the highest level in roast beef (118.23 ng/g) and lowest in cured pork (0.14 ng/g) and cold cuts luncheon meats (0.18 ng/g). BPS was also detected in all the 84 individual raw meat and meat products, with the highest level of 257.61 ng/g in roast beef, followed by 190.41 ng/g in organ meats, 110.15 ng/g in beef steak, 27.91 ng/g in veal cutlets, 17.63 ng/g in wieners & sausages, and 15.27 ng/g in ground beef. However, significant variations of BPS levels were observed in the individual meat and meat product samples under the same category collected from different stores. This may indicate that packaging is unlikely the sources for BPS in meat otherwise BPS levels would have been more or less the same with the same type of packaging (Styrofoam and cling film) regardless where they were collected. Thus, sources other than food packaging, such as the contaminated feed and farming environment (e.g. grass) for animals (e.g. cow), may be possible and should be investigated in future studies.

LC-MS/MS analysis of bisphenol S and five other bisphenols in total diet food samples.

It is already known that bisphenol S (BPS) has been used as a substitute for BPA in thermal papers in recent years. It is not clear, however, if BPS has also been used to replace BPA in can coatings as currently being speculated due to a lack of credible studies on migration of BPS from can coatings and occurrence data of BPS in foods. In this study, an LC-MS/MS method was developed for the analysis of BPS, along with several other bisphenols, and method detection limits for BPS varied from 0.0017 to 3.1 ng/g depending on the type of sample matrix and the amount of sample analysed. This method was used to analyse 159 different food composite samples from a recent Canadian total diet study. Bisphenol E (BPE), bisphenol B (BPB), and bisphenol AF (BPAF) were not detected in any of the 159 food composite samples, bisphenol F (BPF) was detected in only three samples (25-2360 ng/g), and bisphenol A (BPA) was detected in 10 samples (5.3-41 ng/g) which were all prepared from canned foods. BPS was not detected in any of the canned food composite samples but was detected in nine food composite samples prepared from meat and meat products (1.2-35 ng/g), indicating sources for BPS other than can coatings may be possible, which will be investigated in future studies.

p-Cymene, a natural antioxidant, in Canadian total diet foods: occurrence and dietary exposures.

BACKGROUND: There is a lack of information on the presence of volatile organic compounds including p-cymene in foods for dietary exposure assessment. p-Cymene is a monoterpene found in many plant species, which has been used as a flavouring agent in foods and also exhibits antioxidant and antimicrobial properties. While the Joint FAO/WHO Expert Committee on Food Additives (JECFA) has no safety concerns at current levels of intake when used as a flavouring, the current study examines p-cymene levels in foods in general, not just from possible uses as a flavouring, as there could still be a potential health concern if there were high levels of exposure. RESULTS: 159 food composite samples from the 2014 Canadian Total Diet Study were analysed for p-cymene using a gas chromatographic-mass spectrometric method after headspace solid-phase microextraction. Concentrations of p-cymene in the composite samples of most food types were generally low, with a maximum level of 73.5 µg g-1 , detected in the composite sample of herbs and spices. Dietary exposures to p-cymene were estimated for different age groups of Canadian populations. CONCLUSIONS: Although p-cymene was detected in various foods, estimated dietary exposures to p-cymene for different age groups are well below the human intake threshold of toxicological concern established by JECFA of 1800 µg per person per day for structural class I flavours, which includes p-cymene. © 2019 Society of Chemical Industry.

Styrene in foods and dietary exposure estimates.

Low levels of styrene may be found in foods as a result of possible migration from polystyrene-based food packaging and as a result of its formation during the biodegradation of a wide variety of naturally occurring compounds with structures similar to styrene. In this study, composite food samples from a recent (2014) Canadian Total Diet Study were analysed for styrene, and levels of styrene in samples of most food types were low in general with a few exceptions (e.g. 4934 ng/g in herbs and spices). Dietary exposures to styrene were estimated for different age-groups based on the occurrence data and the food consumption data for all persons, and they are 0.17-0.38 µg/kg body weight/day for children and 0.12-0.16 µg/kg body weight/day for adults, similar to air intakes (0.085-0.27 µg/kg body weight/day). Thus, for the general population, both food and air contribute similar portions of the total daily intake of styrene for all age groups. However, for the smoking population, intakes from cigarettes are still the major route of exposure to styrene.

Occurrence of toluene in Canadian total diet foods and its significance to overall human exposure.

Levels of most VOCs in foods are usually low because of their volatility, and human exposure to VOCs is expected to be mainly via inhalation of ambient and indoor air. However, dietary exposures to VOCs can be significant to overall exposures if elevated concentrations of VOCs are present in foods consumed in high amounts and/or on a regular basis, and this was demonstrated in this study with the occurrence data of toluene from the recent 2014 Canadian Total Diet Study (TDS). Concentrations of toluene in the composite samples of most food types from the 2014 TDS are low and similar to the results from the previous 2007 TDS with some exceptions, such as beef steak (670 ng/g (2014 TDS) vs. 14 ng/g (2007 TDS)), poultry, chicken and turkey (307 ng/g (2014 TDS) vs. 8.8 ng/g (2007 TDS)). Toluene concentrations in most of the grain-based and fast food composite samples from the 2014 TDS are considerably higher than those from the 2007 TDS, with the highest level of 4655 ng/g found in the composite sample of crackers from the 2014 TDS (compared to 18 ng/g from 2007 TDS). Dietary exposure estimates for toluene based on the occurrence results from the 2014 TDS show that for most of the age groups, grain-based foods are the primary source, accounting for an average of 77.5% of the overall toluene intake from the diet. The highest dietary exposures to toluene were observed for the adult age groups, with estimated average exposures ranging from 177.4 to 184.5 µg/d. Dietary exposure estimates to toluene are well below oral doses associated with toxicological effects and also below the maximum estimated intake (819 µg/d) from air inhalation for adult group (20 - 70 years) based on the results from CEPA (Canadian Environmental Protection Act) assessment in 1992.

Occurrence of 13 volatile organic compounds in foods from the Canadian total diet study.

Volatile organic compounds (VOCs) are ubiquitous in the environment due to evaporation and incomplete combustion of fuels, use of consumer and personal care products, etc. and they can accumulate in foods. Some VOCs in foods can also be formed during food processing and preparation and migrate from food packaging. In this pilot study, a GC-MS method based on headspace solid-phase microextraction (SPME) was validated and used to analyse selected individual foods which can be consumed directly and 153 different total diet composite food samples for 13 VOCs. Vinyl chloride was not detected in any of the 153 composite food samples, while the other 12 VOCs were detected at various frequencies, with m-xylene being the most frequently detected (in 151 of the 153 samples), followed by toluene (145), 1,3,5-trimethylbenzene (140), ethylbenzene (139), styrene (133), 1,2,4-trimethylbenzene (122), benzene (96), p-dichlorobenzene (95), n-butylbenzene (55), chloroform (45), naphthalene (45) and trichloroethylene (31). Concentrations of the 12 VOCs in most of the food composite samples were low, with the 90th percentiles from 1.6 ng g(-1) for n-butylbenzene to 20 ng g(-1) for toluene. However, some VOCs were detected at higher levels with maxima, for example, of 948 ng g(-1) for m-xylene and 320 ng g(-1) for ethylbenzene in chewing gum, 207 ng g(-1) for styrene and 157 ng g(-1) for toluene in herbs and spices. VOCs were detected at higher levels in most of the individual food items than their corresponding composite samples, for example, the average chloroform concentration in the individual canned soft drinks was 20 ng g(-1) compared with 3.0 ng g(-1) in their composite, and the average toluene concentration in the individual canned citrus juice was 96 ng g(-1) compared with 0.68 ng g(-1) in their composite. Thus, for determination of VOCs in foods which can be consumed directly, their individual food items should be analysed whenever possible for accurate exposure assessment.

Di-(2-ethylhexyl) adipate and 20 phthalates in composite food samples from the 2013 Canadian Total Diet Study.

A sensitive and selective GC-MS method was developed and used for simultaneous analysis of di-(2-ethylhexyl) adipate (DEHA) and 20 selected phthalates in the food samples from the 2013 Canadian Total Diet Study. At least one of the 21 target chemicals was detected in 141 of the 159 different food composite samples analysed. However, only seven of the 21 target chemicals were detected, with di-(2-ethylhexyl) phthalate (DEHP) and DEHA being detected most frequently, in 111 and 91 different food composite samples, respectively, followed by di-n-butyl phthalate (DBP) (n = 44), n-butyl benzyl phthalate (BBzP) (32), di-iso-butyl phthalate (DiBP) (27), di-ethyl phthalate (DEP) (3), and di-cyclohexyl phthalate (DCHP) (1). Levels of DEP (di-ethyl phthalate), DiBP, DBP, BBzP and DCHP were low, in general, with average concentrations of 9.63, 8.26, 23.2, 12.4 and 64.9 ng g(-1), respectively. Levels of DEHA and DEHP varied widely, ranging from 1.4 to 6010 ng g(-1) and from 14.4 to 714 ng g(-1), respectively. High levels of DEHA were found mainly in the composite samples where the individual food items used to prepare the composite were likely packaged in polyvinyl chloride (PVC) wrapping film, while the highest DEHP levels were found in the vegetable and fruit samples.

Levels and temporal trend of bisphenol A in composite food samples from Canadian Total Diet Study 2008-2012.

Food composite samples from the Canadian Total Diet Study which was conducted each year from 2008 to 2012 rotating between different cities were analysed for bisphenol A (BPA). The overall levels of BPA in the composite food samples from each of the five years from 2008 to 2012 were similar in general with averages (range) of 7.7 ng/g (0.20-106 ng/g), 7.8 ng/g (0.26-110 ng/g), 6.9 ng/g (0.20-84 ng/g), 7.7 ng/g (0.20-105 ng/g) and 9.0 ng/g (0.15-90 ng/g) for 2008, 2009, 2010, 2011 and 2012, respectively. Levels of BPA in most of the non-canned food composite samples were low and no particular trends were observed. In contrast, the trend of BPA levels in canned food composite samples over the five years (2008-2012) varies. BPA levels in most of the canned food composite samples from 2008 to 2012 were consistent in general (e.g. canned luncheon meat: 10-18 ng/g, canned baked beans: 18-25 ng/g). While BPA levels over the five years were found to decrease for some canned food composite samples (e.g., canned fish: 109 ng/g in 2009 vs. 51 ng/g in 2012), they were also found to increase for some other canned food composite samples (e.g. canned meat soups: 90-104 ng/g in 2011-2012 vs. 29 ng/g in 2008). Thus, recent changes in can coating for food packaging to BPA-free alternatives may have not been fully reflected in all canned food products over the period from 2008 to 2012. Continued monitoring is necessary to more fully assess the potential impact on dietary exposure by the use of BPA alternatives in food contact materials.

Total mercury in canned tuna sold in Canada in 2006.

Total mercury was measured in 156 composites prepared from 936 samples of canned tuna sold in Canada in 2006. Each composite comprised a single brand. Yellowfin tuna contained the lowest concentrations, averaging 0.066 mg/kg. Skipjack tuna contained slightly higher concentrations, averaging 0.132 mg/kg. The highest average concentration was found in the Albacore tuna: mean 0.325 mg/kg, range 0.174-0.507 mg/kg. The second highest concentration among the 49 albacore composites was 0.469 mg/kg. There were 72 composites for which the type of tuna was not specified. The mercury in these averaged 0.095 mg/kg and ranged from 0.016 to 0.237 mg/kg.

Di-(2-ethylhexyl) adipate in selected total diet food composite samples.

Polyvinyl chloride (PVC) food-wrapping films plasticized with di-(2-ethylhexyl) adipate (DEHA) are commonly used by grocery stores in Canada to rewrap meat, poultry, fish, cheese, and other foods. DEHA was assessed as part of the Government of Canada's Chemicals Management Plan. The main source of exposure for most age groups was expected to be food. Although the margin of exposure from food and beverages is considered to be adequately protective, the Government of Canada committed to performing targeted surveys of DEHA in foods and food packaging materials to better define Canadian exposure to DEHA through dietary intake. In order to determine whether more-comprehensive targeted surveys on DEHA in foods should be conducted, 26 food composite samples from the 2011 Canadian total diet study were selected and analyzed for DEHA using a method based on solvent and dispersive solid-phase extraction and gas chromatography-mass spectrometry. These 26 food composites include cheese, meat, poultry, fish, and fast foods, and PVC films were likely used in packaging the individual foods used to make the composites. DEHA was detected in most of the meat, poultry, and fish composite samples, with the highest concentration found in ground beef (11 µg/g), followed by beef steak (9.9 µg/g), freshwater fish (7.8 µg/g), poultry liver pâté (7.4 µg/g), fresh pork (6.9 µg/g), cold cuts and luncheon meats (2.8 µg/g), veal cutlets (2.1 µg/g), roast beef (1.3 µg/g), lamb (1.2 µg/g), and organ meats (0.20 µg/g). Targeted surveys should be conducted to investigate the presence of DEHA in various foods packaged with PVC films in more detail and provide updated occurrence data for accurate human exposure assessment.

Cohort profile: the maternal-infant research on environmental chemicals research platform.

BACKGROUND: The Maternal-Infant Research on Environmental Chemicals (MIREC) Study was established to obtain Canadian biomonitoring data for pregnant women and their infants, and to examine potential adverse health effects of prenatal exposure to priority environmental chemicals on pregnancy and infant health. METHODS: Women were recruited during the first trimester from 10 sites across Canada and were followed through delivery. Questionnaires were administered during pregnancy and post-delivery to collect information on demographics, occupation, life style, medical history, environmental exposures and diet. Information on the pregnancy and the infant was abstracted from medical charts. Maternal blood, urine, hair and breast milk, as well as cord blood and infant meconium, were collected and analysed for an extensive list of environmental biomarkers and nutrients. Additional biospecimens were stored in the study's Biobank. The MIREC Research Platform encompasses the main cohort study, the Biobank and follow-up studies. RESULTS: Of the 8716 women approached at early prenatal clinics, 5108 were eligible and 2001 agreed to participate (39%). MIREC participants tended to smoke less (5.9% vs. 10.5%), be older (mean 32.2 vs. 29.4 years) and have a higher education (62.3% vs. 35.1% with a university degree) than women giving birth in Canada. CONCLUSIONS: The MIREC Study, while smaller in number of participants than several of the international cohort studies, has one of the most comprehensive datasets on prenatal exposure to multiple environmental chemicals. The biomonitoring data and biological specimen bank will make this research platform a significant resource for examining potential adverse health effects of prenatal exposure to environmental chemicals.

The Canadian total diet study design: 1992-1999.

This paper describes the design of the fourth phase of the Canadian total diet study, conducted for the period 1992-1999. During this phase, complete sets of foods were purchased from eight cities (from one of them twice). For each of the sets, individual foods were prepared as for consumption into about 140 different food composites at Kemptville College, homogenised and bottled. Water from Kemptville, Ontario, was used for the preparation of the foods. The composites were stored frozen at -20°C and then analysed in the Food Research Division for chlorinated dioxins and dibenzofurans, pesticides, PCBs and trace elements. The analytical results were combined with average food consumption values for different age/sex groups, and dietary intakes were calculated. The design of the total diet study provided information to achieve the following goals: (a) background concentrations of the chemicals in the 140 different food composites, (b) average dietary intakes of the chemicals by the population and by different age/sex groups, (c) percent contribution of individual foods and food groups to the dietary intakes, (d) identification of individual contaminated foods and (e) identification of trends in human exposure with time.

Dioxins, furans and non-ortho-PCBs in Canadian total diet foods 1992-1999 and 1985-1988.

In the period from 1985 to 1999, about 600 samples of total diet foods from Canadian cites were analysed for dioxins, furans and non-ortho-PCBs. Toxic equivalent (TEQ) concentrations on a lipid basis were found to be the highest in dairy and beef products followed by poultry and pork. These levels decreased over the 15-year period of sampling, particularly those for fluid milk, less so for poultry and pork and little or no change for beef. Calculation of the human daily intake for the years 1985-1988 showed values a little less than 1 pg of TEQ(2005) polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran per kg body weight, falling progressively to less than 0.5 pg of TEQ in 1999. These estimates are lower than the 2.3 pg of TEQ currently recommended by the WHO. The main categories of foods contributing to the TEQ were animal meats and dairy products, with lesser amounts from fish and other foods.

Survey of total mercury in infant formulae and oral electrolytes sold in Canada.

Total mercury (Hg) was measured in 150 infant formula products (as sold) and oral electrolyte solutions purchased in Canada in 2003. Results less than the limit of detection (LOD) were reported as the numeric value of the LOD. Electrolytes contained the lowest concentrations, averaging 0.026 ng/g. Average levels in milk-based ready-to-use, concentrated liquid and powdered concentrate were 0.028, 0.069 and 0.212 ng/g, respectively. In soy-based formulae, the respective mean concentrations were 0.049, 0.101 and 0.237 ng/g. These concentrations cannot be considered on an absolute basis because 76% of sample concentrations fell below the limit of detection. Despite the inability to measure many of the actual background concentrations, the method was sufficiently sensitive to identify clear cases of low-level Hg contamination (up to 1.5 ng/g) of individual lots of powdered formula. Also, all the different lots of one brand of concentrated liquid infant formulae had significantly higher concentrations of Hg than those of all other concentrated liquid products. After dilution with preparation water, the Hg concentrations in all products would be lower than the Canadian Drinking Water Guideline for Hg of 1 ng/mL and too low to impact on health.

Challenges and trends in the determination of selected chemical contaminants and allergens in food.

This article covers challenges and trends in the determination of some major food chemical contaminants and allergens, which-among others-are being monitored by Health Canada's Food Directorate and for which background levels in food and human exposure are being analyzed and calculated. Eleven different contaminants/contaminant groups and allergens have been selected for detailed discussion in this paper. They occur in foods as a result of: use as a food additive or ingredient; processing-induced reactions; food packaging migration; deliberate adulteration; and/or presence as a chemical contaminant or natural toxin in the environment. Examples include acrylamide as a food-processing-induced contaminant, bisphenol A as a food packaging-derived chemical, melamine and related compounds as food adulterants and persistent organic pollutants, and perchlorate as an environmental contaminant. Ochratoxin A, fumonisins, and paralytic shellfish poisoning toxins are examples of naturally occurring toxins whereas sulfites, peanuts, and milk exemplify common allergenic food additives/ingredients. To deal with the increasing number of sample matrices and analytes of interest, two analytical approaches have become increasingly prevalent. The first has been the development of rapid screening methods for a variety of analytes based on immunochemical techniques, utilizing ELISA or surface plasmon resonance technology. The second is the development of highly sophisticated multi-analyte methods based on liquid chromatography coupled with multiple-stage mass spectrometry for identification and simultaneous quantification of a wide range of contaminants, often with much less requirement for tedious cleanup procedures. Whereas rapid screening methods enable testing of large numbers of samples, the multi analyte mass spectrometric methods enable full quantification with confirmation of the analytes of interest. Both approaches are useful when gathering surveillance data to determine occurrence and background levels of both recognized and newly identified contaminants in foods in order to estimate human daily intake for health risk assessment.

Lead, cadmium and aluminum in Canadian infant formulae, oral electrolytes and glucose solutions.

Lead (Pb), cadmium (Cd) and aluminum (Al) were determined in 437 individual samples of infant formulae, oral electrolytes and 5% glucose solutions available in Canada. In the electrolytes, Cd and Pb concentrations were all below 0.01 and 0.041 ng g(-1), respectively. In the 5% glucose solutions, Pb and Cd levels averaged 0.01 and 0.09 ng g(-1), respectively. Reported on an as-consumed basis, Pb levels in milk- and soya-based formulae averaged 0.90 and 1.45 ng g(-1), respectively, while Cd levels averaged 0.23 and 1.18 ng g(-1), respectively Average Al levels on an as-consumed basis were 440 ng g(-1) (range 10-3400 ng g(-1)) in milk-based formulae and 730 ng g(-1) (range 230-1100 ng g(-1)) in soy-based formulae. Al concentrations increased in the following order: plain formula < low-iron formula < iron-supplemented formula < casein hydrolysate formula ≈ premature formula ≤ soy formula. For example, in the powdered formulae, average Al concentrations were 18 ng g(-1) for plain milk-based, 37 ng g(-1) for low-iron, 128 ng g(-1) for iron supplemented, 462 ng g(-1) for lactose-free, 518 ng g(-1) for hypoallergenic and 619 ng g(-1) for soy-based formula. Al concentrations, as-consumed, increased with decreasing levels of concentration: powder < concentrated liquid < ready-to-use. Formulae stored in glass bottles contained between 100 and 300 ng g(-1) more Al than the same formulae stored in cans. The source of the increased Al did not appear to be the glass itself, because most electrolytes and glucose solutions, also stored in glass, contained less than 8 ng g(-1) Al. Corresponding differences in Pb and Cd levels were not observed. Al concentrations varied substantially among manufacturers; however, all manufacturers were able to produce plain milk-based formulae containing less than 50 ng g(-1) Al, i.e. within the range of Al concentrations found in human milk. Next to soya-based and hypoallergenic formulae, premature formulae contained among the highest concentrations of Al, ranging 851-909 ng g(-1) from one manufacturer and 365-461 ng g(-1) from another.

Historic dietary exposure to perfluorooctane sulfonate, perfluorinated carboxylates, and fluorotelomer unsaturated carboxylates from the consumption of store-bought and restaurant foods for the Canadian population.

Perfluorinated compounds (PFCs) have been detected in humans worldwide and are of health concern. This study measured the concentration of PFCs in composite samples collected for the 1998 Health Canada Total Diet Study and estimated dietary exposure for the Canadian population (older than 12 years of age) using previously collected dietary data (n = 1721). PFCs were detected in 8 samples including processed meats, preprepared foods, and peppers with a range of concentrations from 0.48 to 5.01 ng g(-1) (wet weight). 6:2 fluorotelomer unsaturated carboxylate (FTUCA) was detected in cold cuts at a concentration of 1.26 ng g(-1). Mean daily PFC exposure estimates ranged from 1.5 to 2.5 ng (kg of body weight)(-1). Perfluorinated carboxylates (PFCA C(7)-C(11)) contributed more to PFC exposure than either perfluorooctane sulfonate (PFOS) or FTUCA. Total PFCAs in cakes and cookies, lunchmeats, and green vegetables were the main contributors to dietary exposure, although these exposure levels were below the provisional tolerable daily intake provided by the German Drinking Water Commission. Dietary exposure to total PFCs has not changed over time, although the contribution of PFOS to total PFC exposure may have increased between 1998 and 2004. Further research on the sources of contamination of processed and preprepared foods is required. Dietary exposure to PFCs among Canadians poses minimal health risks based on current toxicological information.