The most common alternative wheel balancing weights are made from
zinc or steel.

Competitively priced lead-free wheel weights, such as steel, aluminum,
copper, zinc, plastic, composites and balancing beads are readily 
available in the U.S. and world markets.

Coated steel wheel weights are the preferred environmentally 
friendly alternative because they can be easily and economically 
recycled with the other steel components of automobiles.

Lead, Mercury, Zinc, aluminum, copper and plastic weights need to 
be separated from steel components in order to be recycled. 

While no technology is absolutely neutral in terms of its 
environmental impact, neither steel nor zinc has the potent toxicity
of lead.

Currently, steel wheel weights are more expensive than lead wheel 
weights. 

An important reason for this additional cost is that the manufacturers
have recently invested in the equipment to produce lead-free weights. 

However, as new tooling equipment is paid for and demand for steel 
weights increases, the cost of environmentally friendly steel wheel 
weights is expected to go down.

The cost of lead contamination prevention is far cheaper than the 
cost of removing lead from the environment

The worst wheel balancing  methods 

(1.) use finger tipped sized lead wheel weights attached to the rim 
of the wheel.

(2.) use mercury contained within an enclosed neoprene tube which is
attached to the entire inside circumference of the wheel rim for 
dynamic wheel balancing. Mercury can escape into the environment.

(3.) Plastic wheel weights are a concern because the plastic is 
abraded by tires on the road and breaks down into unsafe byproducts. 
The plastic sometimes melts under high temperatures causing the 
weights to fall off.

(4.) Also, zinc and copper are toxic to aquatic life.