Acute transperitoneal toxicity for mouse, LD50 =450mg/Kg.
(from http://www.gplantchem.com/kinetin.htm )

and:

Biochem Biophys Res Commun 1994 Jun 15;201(2):665-72
Kinetin delays the onset of ageing characteristics in human fibroblasts.
Rattan SI, Clark BF.
Department of Chemistry, Aarhus University, Denmark.

Kinetin (Kn) is a synthetic cytokinin plant growth hormone having
some
senescence-retarding effects in plants. Its effects on animal cells
have been, until now, best considered as growth inhibitory and
anti-tumorigenic. However, we have observed that an addition of 40-200
microM Kn in the culture medium of human diploid fibroblasts can both
delay the onset and decrease the extent of many of the ageing
characteristics that appear during serial passaging of normal cells in
culture. Age-related changes that are affected by Kn include
morphological alterations, growth rates, cell size, cytoskeletal
organisation, macromolecular synthesis and the intensity of
autofluorescence due to the oxidative damage product lipofuscin. These
anti-ageing effects of Kn are achieved without any increase in the
cell
culture lifespan in terms of maximum proliferative capacity in vitro.
PMID: 8003000
----------------

Encouraging. Perhaps if we are serious about this, we should be keeping some
pet mice. It's not too difficult to do.


Max Watt (Richard Kaufman)