Antioxidant capacity of potato chips and snapshot trends in acrylamide content in potato chips and cereals on the Canadian market.

The concentration of acrylamide was measured in selected varieties of five brands of potato chips and breakfast cereals over a 5-year period. Most of the products were purchased in one locality in Canada. Samples were analysed by an isotope dilution ((13)C(3)) acrylamide method. They were extracted with water, partitioned with dichloromethane, filtered through a 5 kDa centrifuge filter, cleaned-up on HLB Oasis polymeric and Accucat mixed mode anion and cation exchange SPE columns, and analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The acrylamide concentration in potato chips varied from 106 to 4630 ng g(-1), while values in cereals varied from 50 to 347 ng g(-1). Wide variations were observed between brands, within brands over time, and between lots of the same brand. A subset of potato chip samples was analysed for in vitro antioxidant activity. No relationship was found between antioxidative capacity of potato chips and their acrylamide content.

Development of an analytical method and survey of foods for furan, 2-methylfuran and 3-methylfuran with estimated exposure.

Furan has been found to form in foods during thermal processing. These findings, a classification of furan as a possibly carcinogenic to humans, and a limited amount of data on the concentration of furan in products on the Canadian market prompted the authors to conduct a survey of canned and jarred food products. Methyl analogues of furan, 2-methylfuran and 3-methylfuran, were analysed concurrently with furan via a newly developed isotope dilution method, as these analogues were detected in foods in the authors' earlier work and are likely to undergo a similar metabolic fate as furan itself. The paper reports data on 176 samples, including 17 samples of baby food. The vast majority of samples were packaged in cans or jars. Furan was detected above 1 ng g(-1) in all non-baby food samples with a median of 28 ng g(-1) and concentrations ranging from 1.1 to 1230 ng g(-1). Also, 96% of these samples were found to contain 2-methylfuran above 1 ng g(-1) with a median of 12.8 ng g(-1) and a maximum concentration of 152 ng g(-1), while 81% of samples were found to contain 3-methylfuran above 1 ng g(-1) with a median of 6 ng g(-1) and a maximum concentration of 151 ng g(-1). Similarly, furan was detected above 1 ng g(-1) in all baby food samples with a median of 66.2 ng g(-1) and concentrations ranging from 8.5 to 331 ng g(-1). Also, 100% of these samples were found to contain 2-methylfuran above 1 ng g(-1) with a median of 8.7 ng g(-1) and a maximum concentration of 50.2 ng g(-1), while 65% of samples were found to contain 3-methylfuran above 1 ng g(-1) with a median of 1.6 ng g(-1) and a maximum concentration of 22.9 ng g(-1). Additionally, three coffee samples were analysed 'as is', without brewing, and were found to have high levels of furans, especially 2-methylfuran, at a maximum of 8680 ng g(-1). Using this data set, dietary exposures to furan and total furans were calculated. Average furan and total furan intakes by adults (> or = 20 years) were estimated at approximately 0.37 and 0.71 microg kg(-1) of body weight day(-1) respectively.

Mycotoxins in breakfast cereals from the Canadian retail market: a 3-year survey.

One hundred and fifty-six samples of breakfast cereals were collected from the Canadian retail marketplace over a 3-year period. The samples were analysed for the mycotoxins deoxynivalenol, nivalenol, HT-2 toxin, zearalenone, ochratoxin A, and fumonisins B1 and B2 to contribute to dietary exposure estimates in support of the development of Canadian guidelines for selected mycotoxins in foods. The samples included corn-, oat-, wheat- and rice-based cereals, as well as mixed-grain cereals, and were primarily from North American processors. Overall, deoxynivalenol was the most frequently detected mycotoxin--it was detected in over 40% of all samples analysed. Fumonisins and ochratoxin A were each detected in over 30% of all samples. Zearalenone was detected in over 20% of all samples. Nivalenol and HT-2 toxin were each detected in only one sample. The survey clearly demonstrated regular occurrence of low levels of multiple mycotoxins in breakfast cereals on the Canadian market.

N-methyl carbamate pesticide residues in conventional and organic infant foods available on the Canadian retail market, 2001-03.

Seven parent N-methyl carbamate insecticides, in addition to two transformation products of aldicarb (aldicarb sulfoxide and aldicarb sulfone), and a single transformation product of carbofuran (3-hydroxycarbofuran) were measured in infant and junior foods available on the Canadian retail market between 2001 and 2003. Carbaryl and methomyl were the only analytes present at levels above the limits of detection in juice, cereals, fruit, vegetables or meat samples analysed. Carbaryl was the most frequently (7.6%) detected compound and concentrations ranged from 0.6 to 18 ng g-1. Detectable levels of carbaryl were most frequently found in foods prepared with fruit. Methomyl was detected (0.8 ng g-1) in one chicken with broth sample analysed in the present study. In all cases, the concentrations observed were orders of magnitude below the maximum residue limits established for these compounds in the corresponding raw food commodities in Canada (100-10 000 ng g-1). Dietary intakes of carbaryl and methomyl based on the consumption of infant foods tested ranged between 0.2-343 and 0.4-2.0 ng kg-1 body weight day-1, respectively.

N-methyl carbamate concentrations and dietary intake estimates for apple and grape juices available on the retail market in Canada.

Infants and young children consume fruit juices and drinks at rates exceeding those of older children and adults. Carbamate pesticides are known to be used on a broad spectrum of crops, including orchard and vine crops such as apples and grapes. Concern over potential exposure to these acutely toxic pesticides by infants and young children has increased in the last decade. Liquid chromatography with fluorescence detection was used to determine the concentrations of seven N-methyl carbamates and three transformation products in domestic and imported apple and grape juices collected across Canada. Carbaryl was the most frequently (58.6%) detected N-methyl carbamate in juice samples studied. It was observed more frequently in grape juices than in apple or mixed juices. Oxamyl and methomyl were detected in apple juice samples, although they were below detection limits in all grape and mixed juice samples analysed. Maximum levels of carbaryl, methomyl and oxamyl were 93, 6.7 and 4.6 ng ml(-1), respectively. All other analytes were not present in any juice sample at concentrations above the method detection limit (0.3 ng ml(-1)). In all cases, N-methyl carbamate residues were well below the maximum residue limit established for apples and grapes in the Canadian Food and Drug Regulations. No estimated dietary intakes were above the acceptable daily intakes in any age-sex category, where an acceptable daily intake has been proposed. Carbaryl short-term intake estimates were calculated and all were below the proposed acute reference doses.