Background Assessment Criteria

To assess progress towards the objectives of the OSPAR Hazardous Substances Strategy, two assessment tools have been developed Background Concentrations (BCs) and associated Background Assessment Criteria (BACs), and Enviromnental Assessment Criteria (EACs) (OSPAR, 2004). 

The OSPAR solution was the introduction of Background Assessment Criteria. BACs are statistical tools that enable precautionary testing of whether mean observed concentrations can be considered to be near background concentrations. A more detailed... 

Table 2.4.4 Background concentration (BC) and provisional background assessment criteria (BAC) (OSPAR agreement 2005-6) and provisional environmental assessment criteria (EAC) for organochlorines and PAHs in sediment, blue mussel and fish... 

Metal-enzyme complexes, a subgroup of metal-protein complexes, exhibit enzymatic activity consequent to readily dissociable combination with a variety of metal ions. Many of these studies have been performed with unpurified enzymes, and, even when pure enzymes were used, the stoichiometry of the interaction of the metal and enzyme has not been measured. Enhancement of enzymatic activity as a result of the addition of metal ions and its partial loss on their removal has been the chief criterion of assessment of physiological significance. Only in a few instances, e.g., enolase, has the stability and stoichiometry been studied in relation to function (Malmstrom, 1953, 1954). The study of metal complexes and particularly metal chelates (Bjerrum, 1941 Martell and Calvin, 1952 Calvin, 1954) has provided both new experimental and new theoretical backgrounds for the study of metals in relation to the specificity of enzyme action, metal-enzyme (Calvin, 1954), metal-substrate (Najjar, 1951), and metalloenzyme interaction, as well as metal-enzyme inhibition (James, 1953). 

Hauschild MZ, Olsen SI, Wenzel H (1998) Human toxicity as a criterion in the environmental assessment of products. In Hauschild MZ, Wenzel H (eds) Environmental assessment of products. Vol 2 Scientific background. Chapman and Hall, London, UK, pp 315-344... 

A performance assessment has been made to calculate the incremental activity concentrations equivalent to the risk threshold specified in the de-licensing criterion. It is also necessary to be able to determine the background . 

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