Novel Approach for Food Safety Evaluation. Results of a Pilot Experiment To Evaluate Organic and Conventional Foods

Abstract

There is evidence that organic food often contains relatively high amounts of natural toxic compounds produced by fungi or plants, whereas corresponding conventional food tends to contain more synthetic toxins such as pesticide residues, but only a few studies have evaluated the impact of their consumption on health. This study proposes a novel approach to evaluate the potential health risk of organic compared to conventional food consumption, that is, the assay of sensitive markers of cell function in vulnerable conditions. The markers utilized were intestinal and splenic lymphocyte proliferative capacity and liver acute-phase reaction, both responding to the presence of toxins. The vulnerable conditions in which body defenses can be less efficient were weaning and protein-energy malnutrition. This study reports the results of a pilot experiment on one sample of eight varieties of organically and conventionally grown wheat. Weaned rats were assigned to two groups fed conventional (CV) or organic (ORG) wheat for 30 days. Each group was divided in two subgroups of well-nourished (WN) or protein-energy-malnourished (PEM) rats. For each rat, the lymphocyte proliferation was assayed by [(3)H]thymidine incorporation after stimulation of cells with a mitogen, in a culture medium containing either commercial fetal calf serum (FCS) or the corresponding rat serum (RS) to mimic the in vivo proliferative response. The acute-phase proteins (albumin, transthyretin, transferrin, ceruloplasmin, retinol-binding protein) were measured in plasma by Western blotting and immunostaining with specific antibodies. The proliferative response of lymphocytes cultured with FCS and the amount of acute-phase proteins of rats fed the ORG wheat sample, either WN or PEM, did not differ from those of rats fed the CV wheat sample. However, the proliferative response of lymphocytes cultured with RS was inhibited in PEM-CV compared with PEM-ORG. The content of mycotoxins was highest in the organic sample, and therefore the immunotoxic effect was probably due to other contaminants in the CV wheat. In conclusion, these results indicate that the conventional wheat sample tested represented a higher risk for lymphocyte function than the wheat sample organically grown, at least in vulnerable conditions.

Can Agricultural Cultivation Methods Influence the Healthfulness of Crops for Foods?

“…1,18 No systematic nutrition-related health effects have been established either; however, some studies have shown that immunological parameters and growth might be sensitive to effects from cultivation systems. 14,21,22,42 Cultivation Methods Effect on Nutritional Quality and Health Biomarkers. The rats used in the current study were all clinically healthy, with normal food intake and increase in body weight during the long-term feeding experiment without any remarkable deviations from a "normal physiological response".…”

“…A study by Finamore et al 22 observed a difference in lymphocyte function in rats due to cultivation system.…”

“…It is known that factors such as year, time of harvest, seasonal and climatic variations, genotype, and field location can affect the nutritional composition of the plants, which in turn could influence the healthfulness. 23−29 However, the Lauridsen et al 21 experiment suffered, as most of the well-performed animal and human studies to date including the above-mentioned studies, 14,22 from the fact that there were no field replicates per diet, which makes it impossible to estimate the variation due to factors such as location and year. The overall objective of the present study was to investigate if there are any health effects of the long-term consumption of crops from different cultivation systems.…”

Rats show differences in some biomarkers of health when eating diets based on ingredients produced with three different cultivation strategies

“…Most focus has been given to the growth and reproduction of animals, and found no consistent effects 4 and the results from the oldest studies are unlikely to be relevant for modern farming practices. 7 One recent study of rats fed conventional or organic wheat showed increased lymphocyte function in the organic treatment, 19 but the model used had little relevance for most human consumers of organic food.…”

Application of an untargeted metabolomics approach for the identification of compounds that may be responsible for observed differential effects in chickens fed an organic and a conventional diet

“…Major reasons are the care for animals, the environment, but also the potential benefits for the health of the consumer (Finamore et al, 2004;Rembialkowska, 2007;Givens et al, 2008). A large number of studies (Rembialkowska, 2007;Baker et al, 2002;Jestoi et al, 2004;Hoogenboom et al, 2008) have addressed the latter issue, focusing e.g.…”