• Many standard risk assessments deliberately overstate the exposure of people to environmental contaminants by estimating exposure for a theoretical "Maximally Exposed Individual," rather than the average person.
  
  
• Since maximum exposure is calculated on the basis of predictive models rather than direct measurements, it can lead to overestimates of exposure to carcinogens, for example, by a factor of 10 to 100.
  
  
• And since estimates of the risk to population groups are based on theoretical models rather than actuarial data, many cancer risk assessments may be wrong by a factor of 100, 1,000 or more.
  
  
• Some risk assessments assume that all animal carcinogens also cause cancer in humans, when several chemicals that cause cancers in an animal species have been shown to have no effect on humans.
  
  
• They also assume that one can predict the probability of tumor growth in humans taking 1/10,000th the dose given experimental animals, when the evidence shows that in many cases "the dose makes the poison."

Superfund, the federal program created in 1980 to clean up hazardous waste sites, is largely viewed as a super failure. Critics say that the heart of the problem is its liability system -- in which fairness and justice play no part in determining who pays for cleanups.

• Taxpayers and the private sector have poured $90 billion into cleaning up waste.
• Yet less than 18 percent of sites have been cleaned, and the average cleanup takes more than 10 years.
• Businesses that disposed of waste in full compliance with the law at the time of disposal face significant exposure and future liability.
• Even firms that contributed little to the mess in the first place can be required to shoulder the financial burden of the entire cleanup.

Although President Clinton in his 1993 State of the Union message called Superfund a "disaster," the White House has so far balked at reforming the program and making it more fair -- for example, by repealing its retroactive liability provisions. Rep. Bill Zeliff (R-NH) has proposed a repeal of the retroactive provisions, but that reform is losing support in the House. Others contend Washington has no business cleaning up waste sites, which are essentially a state and local problem, and that responsibility should devolve back to these levels of government.

Source: Raymond J. Keating, "Superfund: Saved by Gridlock?" Investor's Business Daily, January 3, 1996.

• "Measurable" back in 1958 meant measurement in terms of parts per thousand.
  
  
• But today, we can measure in parts per trillion - and sometimes even parts per quintillion.
  
  
• Thus, the EPA has no choice but to ban 85 uses of 38 active ingredients in pesticides.