Effect of temerature on Toxicity of heavy metals to Earthworm Lumbrius terrestris

S. Akhtar Ahmed, Asma Khan, Abel Salazar, Jassica Gurumendi, and MAQ Khan

Toxicity of copper, cadmium, lead, and zinc to earthworm L. terreatris increases with temperature. Temperature increases the rate of aerobic metabolism up to 180C and then the metabolism is lowered to only 20% of that at 160C. The rate of oxygen consumption by worms is lowered by heavy metals at all temperatures. Temperature increase increases the hemoglobin concentration in blood, which is lowered by heavy metals. The inhibition of metabolism and hemoglobin concentration by metals does not seem to relate with their toxicity. Absorption spectra of blood of metal-exposed and unexposed worms show differences 420 and 560 nm peaks. In addition to lowering hemoglobin concentration (total oxygen carrying capacity of blood) heavy metals appear to lower the oxygen affinity of hemoglobin. The two together may affect the lowering of oxygen consumption.  Temperature increases associated with global warmingmay have affects on toxicity of heavy metals and other chemical pollutants, which suppress aerobic metabolism.