(full paper is archived in the Miller Library)
Title: The effect of DDT on spine regeneration in sea urchins as measured by the uptake of Calcium-45
Student Author(s): Moitoza
Faculty Advisor(s): Pearse, John S
Location: Final Papers Biology 175H
Date: June 1971
Keywords: marine pollution
Abstract: Sea urchins (Strongylocentrotus purpuratus and S. franciscanus) in the vicinity of the Los Angeles County sewer at White's Point have abnormal spination (stunted and missing primary spines). There are very high DDT residue levels (mainly DDE) in the tissues of these animals compared with normal appearing animals found at Pigeon Point, San Mateo County. Calcification rates in regenerating spines of S. purpuratus from White's Point were one-half the rates of regenerating spines of S. purpuratus from Pigeon Point. DDT in concentrations above 1 ug/ml appears to suppress calcification in regenerating spines of S purpuratus from White's Point exposed to DDT concentrations up to 10 ug/ml. Accumulated pesticide residues contained in the spines of the White's Point urchins apparently suppresses calcification and may be a major cause of their stunted, abnormal appearing spination.