ACUTE TOXICITY OF AGROCHEMICALS AND DETERGENT ON TADPOLES OF THE COMMON AFRICAN TOAD, Amietophrynus Regularis

Abstract

Changing urban ecology has increasingly put amphibians living in swampy portions of coastal
city centres in constant threat of mortality resulting from acute toxicity effects. In this study;
commonly used agrochemicals (Antrarine, Carbofuran, Cypermethrin and Pirimiphos methyl) in
urban gardening and farms in Lagos and a linear alkyl benzene sulphonate (LABS) detergent
commonly used in household washing were exposed to tadpoles (external gill stage) of the
African toad, Amietophrynus regualaris in 96 hrs acute toxicity assays. All test substances were
found to be acutely toxic to the tadpoles from 48 hrs following exposure. The pesticide
Carbofuran exhibited the highest level of toxicity (48 hrs LC₅₀- 4.27 ing/L, 72 hrs LC50- 1.48
mg/L, 96 hrs LC₅o- 0.97 mgIL), in most cases, the herbicide, Antrarine had the least toxicity to the
tadpoles (48 hrs LC₅₀- 156.62 mg/L; 72hrs LC50- 135.23 mg/L, 96 hrs LC₅₀- 60.83 mg/L). Despite
the level of development and technological advancement in urban centres, there remains the need
for cautious use of synthetic products because they pose threats to sensitive and ecologically
important organisms living at the fringes of the remaining natural ecosystems.