A Short-Term Bioassay for Whole Plant Toxicity

Abstract

A five-day, whole plant toxicity test was developed and evaluated. The 18 chemicals tested were primarily substituted benzenes and phenols, although representative herbicides, surfactants, and other industrial chemicals were also tested. The test yields information on root and shoot growth as a function of toxic chemical concentration in the root environment and can also be used to determine the effect on transpiration. The measurement found to be the most sensitive indicator of toxicity was total plant growth. EC50 (effective concentration that reduced growth 50%) values were estimated for each compound using regression analysis. This simple bioassay gives a quick response to an acute exposure and can be used to screen chemicals at various concentrations. The beginning of a unique database comparing species, concentrations, and chemical toxicity are presented, and the results are discussed in relation to other phytotoxicity data.

Transpiration as landfill leachate phytotoxicity indicator

“…The presence of phytotoxic compounds in soil causes a decrease of transpiration. Pfleeger et al (1991) revealed the influence of benzene and phenol on transpiration of barley and soy, but Stefanakis et al (2013) have found, that the constructed wetland receiving the phenol increased the evapotranspiration values. Thompson et al (1998) confirmed reduced transpiration of poplar seedlings under the presence of 2.4.6-trinitotoluene.…”

Statistically significant deviations from additivity: What do they mean in assessing toxicity of mixtures?

“…Relative root elongation (RRE, %) was chosen to be the toxicological endpoint of lettuce to exposures of Cu, Cd, Ni and their binary mixtures due to a relatively higher sensitivity of seedlings than seeds (Pfleeger et al, 1991) and the influence of non-simultaneous toxicity testing already considered in the formula. The length of the root was measured before and after 4 d exposure, from the transition point between the hypocotyls and the root to the root tip (EPA, 1988).…”

Comparing growth development of Myriophyllum spp. in laboratory and field experiments for ecotoxicological testing

“…can be rooted from vegetative cuttings. Those cuttings were taken for the experiments because seeds may often be less sensitive to chemicals that are present in their ambient environment (see Table 1; Pfleeger et al 1991;Walsh and Weber 1991).…”