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Effect of diatom lipid composition on the toxicity of trichlorobenzene. II. Long-term effects of 1,2,3-trichlorobenzene

1993; Springer Science+Business Media; Volume: 24; Issue: 2 Linguagem: Inglês

10.1007/bf01141354

1432-0703

Linda Sicko‐Goad, Norman A. Andresen,

Water Quality Monitoring and Analysis

Exposures of four diatoms,Cyclotella meneghiniana, Melosira italica, Melosira varians, andSynedra filiformis to 0.3 ppm 1,2,3-trichlorobenzene were initiated at the 8th and 11th hours of the light period on a 16:8 h L/D cycle at 20°C. Cell counts, lipid content, and lipid class composition were monitored for 10 days.Melosira italica demonstrated the most long-term effects. Cell counts and chlorophylla were greatly reduced on the 10th day when exposure was initiated in the 11 th hour of the light period inS. filiformis and in the 8th hour of the light period inM. varians. The data demonstrate that more immediate effects occur when exposures are initiated during periods of high polar lipid content or when polar lipids are being synthesized. Long-term effects are observed when exposure initiation occurs during periods of high neutral lipid content and higher total extractable lipid. The results suggest that the response of diatoms to low levels of chlorinated benzenes is related to normal variation in diel lipid composition. These results are repeatable, they vary with species, and exposures initiated at different times of the day may produce quite different results.