Toxicity of water-soluble gasoline fractions to fourth-instar larvae of the mosquito Aedes aegypti L.
Abstract The toxicity of water-soluble components of gasoline to laboratory-reared fourth-instar larvae of the mosquito, Aedes aegypti (L.) was investigated. A median lethal dose (LD50) and a non-lethal dose (NLD) were established for these larvae following a 24 h exposure to water-soluble fractions of benzene, toluene, and xylenes. Based on the actual amount of each component in solution, static toxicity/bioassays showed that acute toxicity of these monoaromatics increased in the sequence benzene, toluene, xylenes. However, toxicity increased in the sequence xylenes, benzene, toluene when results were examined with respect to the amount of aromatic added to water to produce the LD50. The importance of determining the concentrations of compounds dissolved in water when conducting any investigation of biological effects of water pollutants is stressed.