Fixit: Ashes to ashes: The lowdown on cremation

Q I plan on being cremated. Can I mix my ashes with my dog's?

A Well, yes, but don't plan on a cemetery burial. Most cemeteries limit burial to human remains only.

Q How does cremation work, how long does it take? Is the body really reduced to ashes?

A The body is put into a chamber for 2½ hours at 1,600 to 2,000 degrees. All that remains is some bone fragments and ash, said Kevin Waterston of the Cremation Society of Minnesota. With the assist of a magnet, the remains are combed through to recover metal parts such as pins or joints. The remains are then pulverized to create an even, gritty mixture. The metal pieces, with the exception of dental gold, are disposed of by the mortuary or returned to the family, on request.

Q What happens to the gold?

A Because gold beads up into very small, BB-like spheres, they are almost undetectable. And gold isn't picked up by a magnet. The small amount of gold in a body stays with the remains, Waterston said.

Q Is there any preparation of the body before cremation? Must it be embalmed first?

Q What problem do dental fillings pose?

A Mercury pollution. Dental amalgam fillings (sometimes called silver fillings) contain mercury. As solids in the mouth, they are considered inert and not a hazard, but when exposed to high temperatures, the mercury vaporizes and becomes airborne, contributing to mercury pollution in the state and beyond.

While there isn't a large amount of mercury in any one body, the state estimates that, all together, cremation emits about 80 pounds of mercury a year in Minnesota, said Ned Brooks of the Minnesota Pollution Control Agency. The aging baby boomer population tends to have lots of these fillings and as more people choose cremation, pollution isn't expected to drop.

Just a little mercury released into the air can cause problems. Mercury makes its way through the food chain through fish and then into the people and wildlife that eat the fish. Mercury builds up in the human body, where it can harm the brain and nervous system. Young children, developing fetuses and breast-fed babies are most at risk. Once dispersed into the environment, mercury cannot be recovered.

A bill presented to the State Legislature last year would have required crematories to have a dentist remove fillings before cremation or add mercury-capturing equipment, but it did not become law.

Those in the industry aren't against mercury control, he said, but they want proof that the extra expense is warranted. They await study results that will quantify mercury emissions.

Q Can a person request that mercury fillings be removed before cremation?

A Yes. "It's what I plan to do," said Brooks.