  Extra-galactic planetary nebulae (PNe) permit the study of dust and molecules
in metallicity environments other than the Galaxy. Their known distances lower
the number of free parameters in the observations vs. models comparison,
providing strong constraints on the gas-phase and solid-state astrochemistry
models. Observations of PNe in the Galaxy and other Local Group galaxies such
as the Magellanic Clouds (MC) provide evidence that metallicity affects the
production of dust as well as the formation of complex organic molecules and
inorganic solid-state compounds in their circumstellar envelopes. In
particular, the lower metallicity MC environments seem to be less favorable to
dust production and the frequency of carbonaceous dust features and complex
fullerene molecules is generally higher with decreasing metallicity. Here, I
present an observational review of the dust and molecular content in
extra-galactic PNe as compared to their higher metallicity Galactic
counterparts. A special attention is given to the level of dust processing and
the formation of complex organic molecules (e.g., polycyclic aromatic
hydrocarbons, fullerenes, and graphene precursors) depending on metallicity.
