Growth response of four micro-algae to three crude oils and a furnace oil

Abstract

Addition of whole crude oils or furnace oil to cultures of four test algae caused marked reduction in maximum specific growth rate and final yield in a concentration-dependent fashion. Chlorella vulgaris and Selenastrum capricornutum were the most tolerant and the most sensitive species, respectively. Furnace oil was most toxic to the algal forms tested and is followed in a decreasing order of toxicity by Assam, UAE and Bombay high crudes. Differences in chemical composition of test oils are apparently responsible for their differential toxicity to different algae. The present observations demonstrate the suitability of algal bio-assay for the study of whole crude oils, since in this system the algal cells are affected by all the components of crude oils including the water soluble fractions.