|
(M/EH055) Relative initial risk assessment and PTB-profiles for some disinfectants and pharmaceuticals. van Wezel, Annemarie1, Jager, Tjalling1, 1 ABSTRACT- For three examples of both disinfectants and pharmaceutical substances (the disinfectants biphenylol, 4-chloro-m-cresol and triclosan and the pharmaceuticals ivermectin, ibuprofen and oxytetracycline) a PTB-profile and a relative initial risk assessment was made assuming a standard emission. The PTB-profile is based on the so-called intrinsic chemical properties persistence, toxicity and bioaccumulative potential. For each of these three properties distinct cut-off leveles are defined, related to a distinction in environmental risks. The three properties are integrated, and substances are defined in terms of having 'high priority', 'medium priority' or 'low priority'. For relative initial risk assessment, the same type of data is needed as for the PTB-profile. Based on an assumed standard rate of emission, the corresponding environmental concentration in the various compartments is calculated. The modeled environmental concentration is compared to concentrations yielding adverse effects. This procedure is termed 'relative initial risk assessment', as no information on actual emission of the chemical is needed. The PTB criterion does not distinct between the risks of the various chemicals evaluated; all chemicals are classified as 'low priority pollutants'. The relative initial risk assessments yield a nine order magnitude difference in the relative risks of the studied compounds. The relative risks for various environmental compartments differ strongly for some compounds, while for other compounds the risks for the different compartments are comparable. It is concluded that the relative initial risk assessment has a higher discriminative value and yields more information compared to the PTB-criterion. At the low assumed emission of 1 kg/d already a risk is predicted for ivermectin, and an emission of 100 kg/d would result in impermissible risks for triclosan. For ibuprofen and oxytetracycline an emission of 1000 kg/d would result in risks according to our calculations. Key words: ERA, PTB, Pharmaceutical, Desinfectant |
