523 zero risk

QRA results can guide decision makers in their quest for continuous improvement in risk reduction, but zero risk is an unattainable goal. Any activity involves some risk. Even if it were hypothetically possible to eliminate the risk of every accident scenario in a QRA, some risk would still remain because no QRA examines every possible accident scenario. At best a QRA identifies the dominant contributors to risk from the system as it existed at the time of the analysis. Once those are eliminated, other minor risk contributors (including many that were left out of the original QRA because they were negligible contributors, as well as new risks introduced by changes to eliminate the original risks) remain as the new dominant risk contributors. 

The extent of cleanup that is necessary to protect human health and welfare aries with different use ctitegories. Residential development is probably the most sensiti e type of land use because of the long-term and multiple e.xposure routes and because of potential e.xposure to the most sensitive population segments (e.g., children and elderly persons). E.xcavation and removal appears to be the remedial tiction alternative selected at most sites where there is redevelopment. This is because no one can guaratitee tliat a site is stife (i.e., offers zero risk) unless all contaminants are removed. Neitlier a developer nor a municipality can accept responsibility for site safety as long as haznrdous materials remain there. In situ treatment approtiches are seldom iewed is the best option because they are unproven and because 100% detoxification or stabilization caimot be achieved. 

Economic Considerations Quality systems like the GMPs and the ISO norm do not require operations to be economical it is recognized, however, that zero risk implies infinite costs, and that the type and amount of testing should be scientifically justified such that there is reasonable assurance that a product meets specifications that are in line with the associated risks and the intended use pattern, and still are affordable. 

It is important to note that for a particular substance the assumption of carcinogenicity to humans may be false, even though it is a proven carcinogen in several animal species. In such a case, the lower bound on the excess risk to humans is effectively zero, in the sense that zero-risk is a possibility which cannot be... 

There has been a gradual move in environmental policy and regulation from hazard-based to risk-based approaches. This is partly due to the recognition that for many environmental issues a level of zero risk is unobtainable or simply not necessary for human and environmental protection and that a certain level of risk in a given scenario is deemed acceptable after considering the benefits. 

In contrast, the Food Additive Amendments of 1958 to the Food, Drug and Cosmetic Act presented a different type of law, a "zero-risk" law. Under the thrust of the zero-risk law, it said "if a food additive is a carcinogen, we cannot permit any exposure since we cannot live with any such risk." Risk is the evaluation of severity of toxicity or hazardous properties... 

Although medical products are required to be safe, safety does not mean zero risk. A safe product is one that has reasonable risks, given the magnitude of the benefit expected and the alternatives available. All participants in the medical product development and delivery system have a role to play in maintaining this benefit-risk balance by making sure that products are developed, tested, manufactured, labeled, prescribed, dispensed, and used in a way that maximizes benefit and minimizes risk. ... 

There is a threshold in the dose-response curve, or the curve drops toward zero risk more quickly than is suggested by the LNT. 

The actual dose-response curve falls toward zero risk more slowly than is indicated by the LNT (it is a so-called superlinear model). 

But such absolutely safe situations are not of much interest. While the use of some chemicals can be banned, it is not realistic to expect this approach to be applicable to all industrial chemicals, consumer products, or to the polluting by-products of industrial society. If the goal of absolute safety (zero risk) from these products is desired, then such wholesale banning would be necessary. We do not appear ready to turn back the calendar 200 years. 

This approach was, in theory, more satisfactory than the absolutist approach, because it defined safety not in terms of the scientifically meaningless and indefinable zero risk standard (requiring banning, to ensure zero exposure, unacceptable as a general approach, as discussed earlier), but in terms that are scientifically meaningful because they do not require the impossible proof that something (risk) is absent. Safety, under this view, is a condition of very low risk. 

The inclusion of a sustainability perspective by all interest parties means that many previous views have had to be revised. An (eco)toxic zero risk or minimal risk is not always appropriate against the background of limited resources, the desire for innovation and when an action needs to be plaimed. The formulation of implementable and measurable objectives for action is a more realisable target. 

Since the idea of a zero risk of food in principle cannot be realised, it is not least an ethical request to set the assessment of naturally occurring biological active substances on a new basis corresponding to the rules of a scientifically substantiated risk assessment. 

This causes two problems in cancer-risk policy. First, because the public (and, hence, policymakers) worries about small levels of increased cancer risk resulting from chemical exposures, the number of subjects required to differentiate small risks from zero risk is enormous, which makes the studies prohibitively expensive. Second,... 

Third, more sophisticated products and the public expectations of zero risk are driving up the cost of state-of-the-art medicines. At the same time, health care cost containment and demands for better access to pharmaceutical products from an aging population and from third world countries are forcing prices downward. 

Absolute safety (or zero risk) does not exist for several reasons first, it is possible that several protection measures or safety elements can fail simultaneously second, the human factor is a source of error and a person can misjudge a situation or have a wrong perception of indices, or may even make an error due to a moment s inattention. 

Many of the concerns are not expressed as allegations of harm to health, but as philosophical positions. Some of these are that there is not a "no-effect level" or such a thing as a safe exposure level. There is a strong philosophical position which states that a person wishes to experience "zero risk". 

This will take the form of "I don t care if you just proved that this herbicide will not harm us, we don t want to be exposed to any. We want zero risk."... 

Identification of risk levels and margins of safety in comparisons with other commonly encountered chemicals do not finally solve the problem whether a particular chemical risk constitutes a socially acceptable risk. This must finally be determined in the social institutions mentioned earlier at the various political jurisdictions. Whether a risk will be socially acceptable depends not only on the level of risk, which we have dealt with here, but on the nature of the risk, on who assumes the risk, who receives the benefit, and one s personal philosophy of accepting any risk versus zero risk. 

CHAIRMAN SEGLIN Zero risk corresponds to zero profit. 

S. 1480, the original Bill reported by the Senate Environment and Public Works Committee (2 ) was a zero-release, zero-risk bill. It contemplated clean-up of spills and old dump sites down to a no-detectable-presence, zero-risk, level. No allowance was made for risk analysis, comparative risk analysis, or balanced decision-making where response action and its cost would bear a reasonable relationship to the risk. Instead, cost factors were put aside in favor of a liability scheme to tap deep corporate pockets for whatever expense would arise. 

It emerged in the White House discussions that EPA was not really interested in zero-risk clean-up. EPA just wanted to preserve its discretion regarding level of clean-up and its leverage over other responsible companies. Industry, on the other hand, wanted to get on with reasonable clean-up, but did not want to leave EPA and Justice with the discretion and leverage of S. 1480. The fear was that they would insist on massively expensive and unnecessary clean-up. 

The statutory provisions have failed to end the controversy over risk assessment. From the outset some environmental groups have argued that the risk assessment, cost-effectiveness provisions of the NCP are meant to apply only to government-financed clean-up under Section 104 and do not apply to private clean-up under Section 106 or to voluntary private clean-up (4 ). Instead, they advocated that private clean-up be handled on a separate track oriented towards Justice Department enforcement of complaints which would be based on a zero-exposure, zero-risk theory. 

Similarly, an "insignificant risk" classification is judged as defining those situations which do not justify or warrant the allocation of resources for further risk reduction. I must emphasize at this point that the "insignificant" classification is not equivalent to an absolute "zero risk."... 

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