CYANOTOXINS BIOACUMULATION IN THE Hypophthalmicthys molitrix (SILVER CARP) OF THE PARANOÁ LAKE – DF- BRAZIL - A SANITARY RISK

OLIVEIRA N. B., SCHWARTZ C. A., PIRES JÚNIOR O. R

Laboratório de Toxinologia, Departamento de Ciências Fisiológicas - IB, UnB.

Microcystins are hepatotoxic cyanotoxins, that provoke serious liver internal injuries. Some studies indicate that microcystins can bioaccumulate in aquatic animals, and possibly be transferring through the web food. Paranoá Lake is an artificial reservoir on purposes of offering recreation activities and enhancement of the microclimate in Brazil's Federal Capital. It is the most preferable place for non-professional and professional fisheries and the population that lives around the lake usually consumes the fishes. Three individuals of Hypophthalmicthys molitrix (Silver carp), phytoplanktivorous fish, had been collected biweekly, May to June/2006 next to ETE SUL (Treatment Sewer Station of the CAESB). The individuals were dissected in muscle and liver, the tissues were extracted with MeOH (1g/5ml). Then, semipurified with SPE C-18. The analysis were performed in a HPLC system: mobile phase 20 mM ammonium formate in 30% Acetonitrile, corrected pH to 5. The toxin identification was made by comparing the retention time and the spectrogram in 200-300nm range with microcystin-LR standard. In all samples, the microcystin-LR equivalent concentration, were higher than recommended for human consume (0,04 ng of microcystin/g of body weight, Chorus and Bartram, 1999(1)). In this time, liver was between 9,9 to 39,9 ng/g, and muscle 1,5 to 15,9  ng/g. In this study we do not recommend the consume of H. molitrix. These preliminaries results are from a 1 year project for monitoring the dynamics of microcystins in aquatic animals of Paranoá Lake.

KEY WORDS: microcystin, cianotoxin, silver carps, Hypophthalmicthys molitrix, Paranoá Lake, Microcystis, Cyanobacteria.

1- Chorus, I., Bartram, J.. Toxic cyanobacteria in water. A guide to public health consequences, monitoring and management. London: E & FN Spon on behalf of WHO, 1999, p. 416.

FINANCIAL SUPPORT: CNPq.

CORRESPONDENCE TO:Graduation Student: Natiela B. de Oliveira and Teacher Adviser: Osmindo R. P. Júnior, Laboratório de Toxinologia, Instituto de Ciências Biologicas – IB, UnB, Campus Darcy Ribeiro - Asa norte, Brasília, Fone:55-61-33072160, FAX:55-61-32741251, natiela@gmail.com.br and osmindo@unb.br