Ocorrência de aflatoxinas em farelo de algod？o (Gossypium hirsutum L.) na safra de 1986

the occurrence and the level of aflatoxin contamination in 169 samples of cottonseed meals were investigated. the samples were furnished by oil processing plants located in the regions of araraquara, campinas, bauru, paragua？u paulista, guararapes, londrina and maringá in the states of s？o paulo and paraná, brazil, from april to november, 1986. aflatoxin was determined by thin layer chromatography. from the results the following conclusions could be drawn: (1) 114 samples, representing 67.45%, were contaminated with aflatoxin; (2) the level of contamination was considered low with values ranging from less than 10 to 40 ？g/ kg. the latter value held only 12.30% of the total positive samples; (3) there was a significant difference (alfa = 0.05) among the regions studied, maringá showing higher incidence and level of contamination, while araraquara, campinas and bauru lower values; (4) there was no predominance of the aflatoxin incidence any time during the whole processing season; (5) in all investigated samples, b1 was the sole aflatoxin found.