- The literature of hyperaccumulators dose response was reviewed.
- Hormetic dose-response relationships were commonly observed for multiple chemicals.
- Quantitative features of the hormetic dose response were similar across studies.
- Hormetic stimulation was related to metal accumulation in the plant tissues.
- Dose-responses were associated with up- and down-regulation of adaptive mechanisms.
Accumulation of metals by plants is an important area of investigation in plant ecology and evolution as well as in soil contamination/phytoremediation practices. This paper reports that hormetic-biphasic dose-response relationships were commonly observed for multiple agents (i.e. arsenic, cadmium, chromium, fluoride, lead, and zinc) and 20 species in plant (hyper)accumulator studies. The hormetic stimulation was related to metal accumulation in affected tissues, with the metal stimulation concentration zone unique for each metal, species, tissue, and endpoint studied. However, quantitative features of the hormetic dose response were similar across all (hyper)accumulation studies, with results independent of plant species, endpoints measured, and metal. The dose-dependent stimulatory and inhibitory/toxic plant responses were often associated with the up- and down-regulation of adaptive mechanisms, especially those involving anti-oxidative enzymatic processes. These findings provide a mechanistic framework to account for both the qualitative and quantitative features of the hormetic dose response in plant (hyper)accumulator studies.
*Original abstract online at https://www.sciencedirect.com/science/article/abs/pii/S0269749121001044?via%3Dihub