Although there are others more familiar than I, this is what I am familiar with....

Some manufacturers (like Paulson) put powdered lead into the chip composition to give more weight. This is supposedly why some manufacturing was moved to Mexico.

Some chips are manufactured with a lead weight in the center of the chip, but it requires breaking the chip open to expose the lead.

An alternate to lead is brass flakes (or shavings) being put intc composition. This adds weight and also give a glittery effect to the chip.

The second issue deals with nicotine poisoning! Chips that have been used as burning cigarette holders can have an accumulation of nicotine that can be absorbed into the skin and other soft-tissue membrane (mouths) of kids and actually cause nicotine poisoning.

In Dick Covington's most recent Talk With The Experts, C. T. Rodges told of his hospital visit with nicotine poisoning as a result of cleaning chips. Yes it was mass quantities, but small kids are more suceptible to such poisons.

Well, thats about all I am aware of in this area.

Jim Follis