Some effects of petroleum hydrocarbons on the growth of freshwater phytoplankton
Coffey, John Calvin
Ward, C. H.
Master of Science
Two algal culture systems were used to investigate the effects on the growth of five phytoplankton species of water soluble fractions of petroleum hydrocarbons. The three test petroleums were a Kuwait crude oil, a South Louisiana crude oil, and a #2 fuel oil which have been designated by the American Petroleum Institute as standard biological test oils. In addition to the oils, naphthalene was tested as a possible simple model compound of petroleum toxicity. The test species were three green algae: Selenastrum capricornaturn, Chlorella pyrenoidosa. and Ankistrodesmus falcatus: and two blue-green algae: Anabaena flos-aquae and Microcystis aeruginosa. No inhibitory effects of the two crude oil water soluble fractions were found on the growth rate of S. capricornaturn or on the cell yield of any of the five species. The #2 fuel oil water soluble fraction was found to inhibit the growth rate of capricornaturn and the cell yield of all of the test species except C. pyrenoidosa. Most of the inhibitory component of the #2 fuel oil water soluble fraction was found to be volatilized within 72 hr with a minor residual inhibitory component present. Naphthalene was found to be toxic to S. capricornatum when continuously saturated by solid phase naphthalene. Naphthalene was found to he rapidly removed from the culture systems by volatilization when the saturated naphthalene solutions were open to the atmosphere; these saturated naphthalene solutions did not inhibit the growth rate or cell yield of canricornaturn.