Environmentalists are very concerned about cremation’s toxic emissions:
Scrubbers, filters, and after-chambers can reduce but not entirely eliminate the raft of pollutants generated by the incineration of a human body. Carbon monoxide (a common product of combustion) and fine soot comprise the primary emissions, but sulfur dioxide (from combustion of the natural gas fuelant) and trace metals (from body parts, among others) may also be produced.
Of all emissions, however, mercury poses the biggest threat to the health of the living. The toxic metal, which is linked to brain and neurological damage in children, is found in dental amalgams.
The cremation retort’s high temps vaporize any mercury in dental fillings of the deceased, sending the metal up the stack and into the atmosphere. From there it’s carried by prevailing winds, some of it falling into lakes and streams, where it’s taken up by fish and other aquatic life — and eventually by humans who consume them.1
The cremation industry claims that they comply with government standards and that new technologies have cut down on dangerous emissions. The problem is that: (a) very few crematories possess the new technologies; and (b) in most places, standards are weak or nonexistent.
In reality, as the New World Encyclopedia reports:
There exists a body of research that indicates cremation has a significant impact on the environment. Major emissions from crematories include nitrogen oxide, carbon monoxide, sulfur dioxide, particulate matter, mercury, hydrogen fluoride, hydrogen chloride, and other heavy metals, in addition to Persistent Organic Pollutants (POP).2
Another commentator gave numbers to the effects of operating a cremation oven:
A typical machine requires about 2,000 cubic feet of natural gas and 4 kilowatt-hours of electricity per body. That means the average cremation produces about 250 pounds of CO2 equivalent, or about as much as a typical American home generates in six days.3
No wonder the green movement is not in favor of cremation.
1 Harris, Grave Matters, 61.
2 New World Encyclopedia, s.v. "Cremation," http://www.newworldencyclopedia.org/entry/Cremation.
3 Rastogi, "The Green Hereafter," February 17, 2009.