Abstract
Plants which are used by traditional healers in Tanzania have been evaluated to obtain preliminary data of their toxicity using the brine shrimps test. The results indicate that 9 out of 44 plant species whose extracts were tested exhibited high toxicity with LC(50) values below 20 microg/ml. These include Aloe lateritia Engl. (Aloaceae) [19.1 microg/ml], Cassia abbreviata Oliv. (Caesalpiniaceae) [12.7 microg/ml], Croton scheffleri Pax (Euphorbiaceae) [13.7 microg/ml], Hymenodactyon parvifolium Brig (Rubiaceae) [13.4 microg/ml], Kigelia Africana L. (Bignoniaceae) [7.2 microg/ml], and Ocimum suave Oliv. (Labiatae) [16.7 microg/ml]. Twelve plants gave LC(50) values between 21 and 50 microg/ml, 11 plants gave LC(50) values between 50 and 100 microg/ml, and 18 plants gave LC(50) values greater than 100 microg/ml.