Microcystins are toxins produced by some cyanobacteria present in cell cultures of microalgae. It is considered to have a powerful hepatotoxic activity and its presence in food is strongly controlled, being 1 μg / L of water the safety limit established by the WHO and 1 μg / g the adaptation of the Oregon government to food products to food products included in microalgae. However, the article used as the main source of information (Fawell et al, 1994) presents methodological deficiencies, such as the use of purified toxins in purified water supplied by probe, in the place of dietary route with the toxin in interaction with all the other compounds present in the microalgae, the use of especially susceptible organisms (mice) and the application of an exaggerated uncertainty factor. In addition, the article presents logic flaws, forcing conclusions on low exposure groups based on observations made in groups with greater exposure and important data for those conclusions in an ambiguous way. Another important error is the conversion of the safety limit of 1 μg / L of water 1 μg / g of microalgae, since it is not based on scientific evidence and ignoring the antioxidants present in the microalgae antagonize the activity of the microcystins. The absence of a WHO justification for the use of the Fawell et al (1994) article over other articles with more appropriate methodologies, including other Fawell articles and similar methodological errors in other more recent articles affected by a greater interest in establish a low safety limit for the presence of microcystins in foods that in establishing an adequate limit based on reliable scientific evidence, weigh the social and economic cost it may have. On the other hand, the numerous articles with methodologies that better simulate the natural conditions of microcystins in the human body, yield safety limits higher than 1 μg / l. Therefore, it is suggested that each food product be tested with a more appropriate methodology to establish a safety limit.
By Nicole Ortegs, Daniel Corea Y Maria Campos
ResponderEliminarMicrocystins are toxins produced by some cyanobacteria present in cell cultures of microalgae. It is considered to have a powerful hepatotoxic activity and its presence in food is strongly controlled, being 1 μg / L of water the safety limit established by the WHO and 1 μg / g the adaptation of the Oregon government to food products to food products included in microalgae. However, the article used as the main source of information (Fawell et al, 1994) presents methodological deficiencies, such as the use of purified toxins in purified water supplied by probe, in the place of dietary route with the toxin in interaction with all the other compounds present in the microalgae, the use of especially susceptible organisms (mice) and the application of an exaggerated uncertainty factor. In addition, the article presents logic flaws, forcing conclusions on low exposure groups based on observations made in groups with greater exposure and important data for those conclusions in an ambiguous way. Another important error is the conversion of the safety limit of 1 μg / L of water 1 μg / g of microalgae, since it is not based on scientific evidence and ignoring the antioxidants present in the microalgae antagonize the activity of the microcystins. The absence of a WHO justification for the use of the Fawell et al (1994) article over other articles with more appropriate methodologies, including other Fawell articles and similar methodological errors in other more recent articles affected by a greater interest in establish a low safety limit for the presence of microcystins in foods that in establishing an adequate limit based on reliable scientific evidence, weigh the social and economic cost it may have. On the other hand, the numerous articles with methodologies that better simulate the natural conditions of microcystins in the human body, yield safety limits higher than 1 μg / l. Therefore, it is suggested that each food product be tested with a more appropriate methodology to establish a safety limit.