Target Risk

Use of absolute risk estimates (i.e., comparison against a target risk value) is more sensitive to uncertainty than is relative use (i.e., risk ranking) (Ref. 4). The reason for this is that, with relative applications, the same methodology and assumptions are usually used to evaluate the various alternatives. As a result, comparative risk estimates are subject to similar uncertainties. 

Risk assessment—The process by which the results of a risk analysis are used to make decisions either through a relative ranking of risk reduction strategies or through comparison with risk targets. Risk assessment is often defined as the qualitative estimation of probability and consequence of an incident or incidents. 

ECETOC. 2004. Targeted risk assessment. ECETOC Technical Report No. 93. Brussels ECETOC. 

ECETOC (2012) Targeted risk assessment tools, http //www.ecetoc.org/tra. Accessed 28 Jan 2012... 

Targeted Risk Drivers. Based on the analysis of principal risk drivers, site assessment and remediation efforts can be focused on the principal risk driver(s) with the largest contribution to risk across the portfolio of sites. In this manner, limited resources can be leveraged to achieve maximum risk reduction. Again, in all cases, priority is given to control of unsafe exposures for human or environmental receptors. 

TR = target risk limit effects of individual contaminants (dimensionless) ... 

Applicable target risk limits (TR) for health protection can be matched to levels specified by the environmental regulatory authority. Toxicological parameters for each contaminant can be determined from published references, such as the U S. EPA Integrated Risk Information System (IRIS). Exposure rates correspond to the chronic rate of contact or intake of the affected exposure medium (air, water, soil) by the receptor under anticipated land use conditions. As a conservative measure, these rates can be estimated based on standard exposure factors published by the regulatory authority or other source (e.g., American Industrial Health Council) for the anticipated land use at the site (e.g., residential, commercial, etc.). 

TRAR (2000) Draft Targeted Risk Assessment Report on Cadmium/Cadmium Oxide as Used in Batteries (2000). Belgian Rapporteur. Mr. M. De Win General Advisor. Ministry of Social Affairs, Service of Risk Management. R.A.C. Vesalius. Pachecolaan, 19.Box 5. B-lOlO Brussels. 

ECETOC (2004). Targeted Risk Assessment, Technical Report No 93, European Centre for Ecotoxicology andToxicology of Chemicals, Brussels. 

REGULATORY STATUS Criterion to protect freshwater aquatic life insufficient data Criterion to protect saltwater aquatic iife insufficient data Criterion to protect human health ambient water concentration is 0 interim target risk level criteria considered by the and 10" ranges 9.7 ng/L, 0.97 ng/L, and 0.097 ng/L respectively... 

REGULATORY STATUS Criterion to protect freshwater aquatic life insufficient data Criterion to protect saltwater aquatic life insufficient data Criterion to protect human health ambient water (quality criterion should be 163 ng/L based on a corresponding lifetime cancer risk below 1x10 a cancer risk level of 1 in 100,000 is imposed by a concentration of 0.123 pg/L interim target risk levels criteria considered by EPA in the ranges of 10 10 and 10 28 ng/L, 2.8 ng/L, and 0.28 ng/L respectively USSR MAC 0.02 mg/L in water bodies used for domestic purposes, and 0 in water bodies used for fishery purposes... 

Risk criteria have been established by some regulatory agencies and companies for fixed-facility risks however, there are very limited such target criteria for transportation risks, with a few companies beginning to use criteria for transportation risks. Where criteria are employed, initial risk estimates are compared against the criteria. If the risk target level is not met or is exceeded, the addition of risk reduction measures to reduce the risk estimate to (or below) the target risk level is evaluated. 

Table 3.8 Safety integrity levels probability of failure on demand, target risk reduction factor and target frequency of dangerous failure to perform the SIF.

Environmental risk assessment is an established feature of modem environmental decisions and has been used successfiilly to target risk management actions on the key drivers of risk across a range of anthropogenic and natural hazards (European Environment Agency. 1998). 

Hypothesis-driven investigation FoUow up to TSA assessment of possible on-target risks and develop customized counter-screens Follow up to observed toxicities during in vivo studies to determine drivers (on-target versus off-target) and characterize translation risk and monitoring... 

Cyclophosphamide monitoring Target risk level Prohibitive risk level... 

OELs for Genotoxic and Sensitising Substances Target Risk Levels... 

Instead of an OEL, then, a target risk level will be identified by governmental bodies, feasibility will be discussed, and a discussion will be repeated every 4 years where necessary [10]. The target risk level states the extent to which exposure must be minimised in order to ensure that the extra risk of harm is negligible or will be reduced to a natural background risk. The feasibility discussirm focuses not only on technical feasibility, but also on operational and economic feasibility. 

In the Netherlands (also in Germany and Switzerland) for instance use is made of a system of feasible risk levels a prohibitive risk level (prohibiting an additional risk of cancer higher than 10 per substance per year) and a target risk level (10 per substance per year). For sensitisation the target risk level corresponds to a 10 extra risk of sensitisation owing to exposure to an inhalant allergen beyond any inherent sensitisation to the substance. 

Safety integrity level (SIL) Target average probability of failure on demand Target risk reduction... 

The key to the process is that the CPSC must select the least burdensome requirement to prevent or adequately reduce the specific, targeted risk of injury. Beyond rule making power, the CPSC also has the legal authority... 

As employed by regulators, PbB cutoff values are assumed to cover one or more unacceptable toxic endpoints and are chosen to minimize unacceptable frequencies of effects in the target population. However, this minimizing rarely permits the prospect of 100% avoidance of toxic health risk within some risk population, so the approach entails both risk assessment and risk management components. As illustration, the latter can take the form of the inclusion of a stated fraction of a targeted risk population to be protected. 

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