<P> Grayanotoxins are produced by plants in the Ericaceae family, specifically members of the Rhododendron, Pieris, Agarista and Kalmia genera . The genus Rhododendron alone encompasses over 750 species that grow around the world in parts of Europe, North America, Japan, Nepal and Turkey . They can grow at a variety of altitudes ranging from sea level to more than three kilometers above . While many of these species contain grayanotoxins, only a few contain significant levels . Species with high concentrations of grayanotoxins such as R. ponticum, R. flavum and R. luteum are most commonly found in Nepal and regions of Turkey bordering the Black Sea . </P> <P> Nearly all parts of grayanotoxin - producing rhododendrons contain the molecule, including the stem, leaves, flower, pollen and nectar . Grayanotoxins can also be found in secondary plant products such as honey, labrador tea, cigarettes and herbal medicines . </P> <Table> <Tr> <Td> Grayanotoxin </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Grayanotoxin I </Td> <Td> OH </Td> <Td> CH </Td> <Td> Ac </Td> </Tr> <Tr> <Td> Grayanotoxin II </Td> <Td_colspan="2"> CH </Td> <Td> </Td> </Tr> <Tr> <Td> Grayanotoxin III </Td> <Td> OH </Td> <Td> CH </Td> <Td> </Td> </Tr> <Tr> <Td> Grayanotoxin IV </Td> <Td_colspan="2"> CH </Td> <Td> Ac </Td> </Tr> </Table> <Tr> <Td> Grayanotoxin </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr>

The national flower of nepal a plant associated with mad honey disease