Mercury vapors are extremely toxic, often causing severe pneumonia. Zinc is used in soldering compounds, galvanized wire, batteries, and certain paints. Zinc is not very toxic. In fact, zinc is a trace element that is required in the diet. A zinc deficiency causes anemia and retardation of growth and development.
Significant excesses are toxic and produce signs similar to lead poisoning.
Because heavy metals are so common throughout the environment, avoidance of exposure is important. Cockatiels should never be allowed to play outside their cages without supervision. Besides heavy metal poisoning, there are many other hazards throughout the home. The environment should be inspected for the presence of heavy metals and the sources should be removed from the area if possible. Since cage and fencing materials are common sources for heavy metals, proper selection of nontoxic materials is important.