Chlorophyll fluorescence from creosote-exposed plants in mesocosms: Validation of a bioindicator

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:460479

Marwood, C A; Harris, M L; Day, K E; Greenberg, B M; Solomon, K R ^[1]

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1. Univ. of Guelph, Ontario (Canada). Centre for Toxicology

The chlorophyll fluorescence assay is a rapid, sensitive measure of photosynthetic competence in higher plants and algae that can be used to detect the impact of toxicants at many sites in the plant cell. Chlorophyll fluorescence was examined in plants exposed to PAHs as part of a study to validate chlorophyll fluorescence as a bioindicator by correlating effects on fluorescence with population-level effects in outdoor mesocosms. The wood preservative creosote was used as a mixed PAH source. Two species of aquatic plants, Lemna gibba and Myriophyllum sp., were exposed to 0.1--100 uL/L of creosote in 12,000 L artificial ponds. Creosote was introduced into the mesocosms using different dosing schemes to simulate leaching and spill events. The pulse amplitude modulated fluorescence technique was used to measure several parameters from plants in situ during a 60-day exposure. Chlorophyll fluorescence parameters were compared to creosote effects on population-level growth. Chlorophyll fluorescence was inhibited by creosote at concentrations above 3 uL/L, which also caused a similar inhibition of plant growth in the mesocosms. However, chlorophyll fluorescence was more sensitive than growth endpoints at low creosote concentrations. The chlorophyll fluorescence assay also detected damage to the photosynthetic apparatus in plants after only a few days exposure to creosote. Thus, chlorophyll fluorescence from plants exposed to creosote was well correlated with environmentally relevant endpoints at the population level. The effects of the different dosing schemes on creosote toxicity will also be discussed.

• OSTI ID: 460479
• Report Number(s): CONF-961149--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
AQUATIC ORGANISMS
BIOLOGICAL INDICATORS
CREOSOTE
PLANTS
POLYCYCLIC AROMATIC HYDROCARBONS
TOXICITY
WATER POLLUTION