Sustainable food systems are those in which diverse foods are produced in close proximity to a market. A dynamic, adaptive knowledge base that is grounded in local culture and geography and connected to outside knowledge resources is essential for such food systems to thrive. Sustainable food systems are particularly important to remote and Aboriginal communities, where extensive transportation makes food expensive and of poorer nutritional value. The Learning Garden program was developed and run with two First Nation communities in northwestern Ontario. With this program, the team adopted a holistic and experiential model of learning to begin rebuilding a knowledge base that would support a sustainable local food system. The program involved a series of workshops held in each community and facilitated by a community-based coordinator. Topics included cultivated gardening and forest foods. Results of survey data collected from 20 Aboriginal workshop participants are presented, revealing a moderate to low level of baseline knowledge of the traditional food system, and a reliance on the mainstream food system that is supported by food values that place convenience, ease, and price above the localness or cultural connectedness of the food. Preliminary findings from qualitative data are also presented on the process of learning that occurred in the program and some of the insights we have gained that are relevant to future adaptations of this program.
In an ongoing study of the hypothesised association between consumption of fish contaminated with persistent organochlorine compounds and low birth weight, a relevant measure of exposure is the accumulated fish consumption over long time periods. An issue of concern in this study is the quality of the retrospective exposure assessments. The present investigation was undertaken to determine the agreement between reported fish consumption in two interviews with approximately one year in between. in order to evaluate its impact on the effect estimates. The agreement decreased with increasing retrospective time interval between interview and focused time period of fish consumption. Furthermore, the exposure assessments based on the two interviews led to considerably different effect estimates.
During the last decade, cases of the fish parasite Anisakis simplex infection and allergy in human have increased in countries with high fish consumption. Our aim was to perform an extended seroprevalence study of anti-IgE antibodies against this parasite in Norway, one of the high fish-consuming countries. At the Department of Immunology and Transfusion Medicine and the Laboratory of Clinical Biochemistry, Haukeland University Hospital, Bergen, Norway, two main groups of anonymized serum samples were collected; the first (n = 993) from recently recruited blood donors (designated 'BDO') and the second (n = 414) from patient with total IgE levels =1000 kU/l (designated 'IGE+'). The sera were analysed by the ImmunoCAP(®) method for total IgE and IgE antibodies against A. simplex, house dust mite (HDM), shrimp, cod, crab, brine shrimp and shrimp tropomyosin. The A. simplex positive sera were further tested by an enzyme-linked immunosorbent assay (ELISA) method, which uses 2 recombinant (r) major allergens, rAni s 1 and rAni s 7 as target antigens. SDS-PAGE and Western immunoblotting analyses were also performed. Whereas the prevalences by ImmunoCAP(®) were 0.4% and 16.2% in the BDO and IGE+ groups, respectively, analyses with recombinant allergens showed only 0.0% and 0.2%. Cross-reactivity and immunoblotting analyses suggested that most of the ImmunoCAP(®) positive sera were probably false-positive due to cross-sensitization to shrimp and HDM. However, positivity due to other A. simplex antigens should also be considered. Compared with other high fish-consuming countries, we observed a very low seroprevalence of anti-Anisakis IgE antibodies in a Norwegian population.
Epidemiological studies suggest that fish consumption may be a protective factor against the development of prostate cancer. We investigated the association between prostate cancer risk and fresh and preserved fish consumption among participants of a population-based case-control study (1,534 cases, 1,607 controls). Fish intake was measured using a dietary questionnaire that collected both frequency of consumption of a given portion size. Logistic regression analysis demonstrated an inverse association between preserved fish and prostate cancer risk for all levels of consumption, but reductions only reached statistical significance for the category of 1 to 3 servings of preserved fish per month (odds ratio = 0.78, confidence interval = 0.64-0.95). Consumption of any fat or energy from preserved fish was also associated with reduced risk. There was no suggestion of reduced prostate cancer risk with consumption of fresh and canned fish. Our results suggest that consumption of preserved fish may reduce the risk of developing prostate cancer.
The natural microflora of cold-smoked fish at the end of shelf-life are lactic acid bacteria (LAB). Some of these display a capacity to inhibit spoilage as well as several strains of pathogenic micro-organisms, e.g. Listeria monocytogenes which is isolated frequently from cold-smoked salmon (CSS). Eight batches of sliced vacuum-packed CSS from Norway, Scotland and Spain were collected at retail. Packs were stored at 5 degrees C and examined for chemical and microbiological characteristics, at purchase date and at expiration date. pH, water activity and salt content were similar to available data on lightly preserved fish products. There was a consistent pattern in the development of the microflora on CSS; the initial level of LAB was low on freshly produced CSS (10(2) cfu g(-1)); however, storage in vacuum packaging at refrigeration temperature was elective for LAB. At the end of the stated shelf-life these micro-organisms, represented mainly by Lactobacillus spp., attained ca.10(7) cfu g(-1) while Enterobacteriaceae counts were consistently lower (10(5) cfu g(-1)), which indicates the ability of LAB to grow and compete with few carbohydrates available and in the presence of moderate salt concentrations. L. monocytogenes was not found in any sample. Forty-one percent of LAB strains isolated exhibited inhibitory capacity against Listeria innocua, in a plate assay. A majority of the inhibitory effects were non-bacteriocinogenic, but nevertheless were very competitive cultures which may provide an additional hurdle for improved preservation by natural means.
Vibrio vulnificus is a bacterium indigenous to estuarine waters and is known to be a significant human pathogen. Infections are generally associated with the consumption of raw oyster. In an attempt to identify possible antimicrobial agents against this organism that might be used in foods, ten compounds that are generally recognized as safe (GRAS) by the FDA were tested against both the opaque and translucent morphotypes of V. vulnificus. Eight of those compounds had a lethal effect for both morphotypes of this bacterium. Diacetyl had the lowest lethal concentration (50 ppm) of the GRAS compounds tested within 24 h. Lactic acid and butylated hydroxyanisole possessed lethal activities at 300 ppm and 400 ppm, respectively, within 3 h. The mode of action of lactic acid against V. vulnificus appears to be an effect primarily of pH, while the antimicrobial activities of diacetyl and BHA appeared not to be affected by pH. No significant differences were found for opaque to translucent, or from translucent to opaque switching, in examining the possible effects of the GRAS compounds on colonial morphology.
World Health Organization (WHO), in cooperation with the Consortium to Perform Human Biomonitoring on a European Scale (COPHES), has developed a standardized methodology for human biomonitoring (HBM) surveys in maternities in order to assess prenatal exposure to mercury. To test this standard methodology and adapt it to Russian settings, a cross-sectional HBM survey involving 120 parturient women was conducted in six maternities of the Moscow Region. Levels of total mercury in maternal hair (geometric mean: 0.21 µg/g, 95th percentile: 0.54 µg/g), cord blood (0.89 µg/L and 2.38 µg/L, respectively) and maternal urine (0.27 µg/L and 0.94 µg/L) in this population were similar to those in other European countries with relatively low fish consumption. Consumption of all types of fish at least once per week during the third trimester of pregnancy compared to fish consumption less than once per month was associated with the increase of geometric mean level of total mercury: in hair by 31% (95% confidence interval: 4%, 66%) higher, in cord blood--by 38% (9%, 74%) and in maternal urine--by 36% (2%, 81%). No biomarker values exceeded levels recommended by WHO or national agencies in the USA and Germany. However; at the population level, adverse effects of prenatal exposures to mercury can still be substantial.
BACKGROUND: Seafood is an important source of long-chain polyunsaturated fatty acids (LCPs), which are essential for normal growth and development. However, the nutritional benefits could be limited by polychlorinated biphenyl (PCB) contamination. In particular, inhibition of desaturase activities by PCBs may affect the maintenance of arachidonic acid (AA) status during development. OBJECTIVE: The aim was to evaluate AA status in a birth cohort from a fishing community with a high seafood intake and a wide range of PCB exposures. DESIGN: We measured LCP concentrations in paired mother and umbilical cord serum samples obtained from 182 consecutive births in the Faroe Islands, where PCB-contaminated whale blubber forms part of the diet. PCB exposure was determined from maternal concentrations. RESULTS: Serum phospholipid AA concentrations averaged 9.14% and 16.5% (by wt) in maternal and cord serum, respectively. After adjustment for gestational age and concentrations of linoleic, alpha-linolenic, and eicosapentaenoic acids, a decrease in AA concentrations of 0.17% (by wt) (95% CI: 0.03%, 0.31%) and 0.31% (by wt) (95% CI: 0.10%, 0.52%) was seen in maternal and cord serum, respectively, for each doubling of PCB exposure. CONCLUSIONS: Increased PCB exposure was associated with a modest decrease in serum AA concentrations, which is in accordance with the experimental evidence of desaturase inhibition by PCBs. Such interference with LCP utilization could attenuate the beneficial effects of the essential lipids contained in seafood. Because AA is of key importance for growth and development, these results suggest that this possible mechanism for PCB toxicity deserves to be explored.
Persistent contaminants such as heavy metals and organochlorine compounds are transported from distant sources to the Arctic by oceanic and atmospheric currents. Natives inhabiting the Arctic can be exposed, because they exist at the highest trophic level of the arctic aquatic food chain, along which biomagnification of contaminants occurs. We reviewed the data available on heavy metal and organochlorine body burden in natives from different regions of Nunavik (northern Québec) and assessed the potential risk of health effects. In addition, we investigated the relationship between each contaminant plasma level and omega-3 fatty acid content of plasma phospholipid, a surrogate measure for aquatic food consumption. Cadmium exposure appears to be unrelated to the consumption of species from the aquatic food chain (r = 0.0004; P = 0.99), whereas PCBs and mercury were (r = 0.49 and 0.52, respectively; P