Risk assessment aquatic pollution

The official list of priority pollutants threatening the aquatic environment is presently based on that reported on Directive 2008/105/EC [27]. It was the output resulting from a previously done risk assessment study carried out by the Fraunhoffer Institute (COMMPS procedure) [28, 29], using monitoring data gathered throughout many European river basins. 

Bakker, D. J., de Vries, W., van de Plassche, E. J., van Pul W. A. J. (1998). Manual for Performing Risk Assessment for Persistent Organic Pollutants in Aquatic Ecosystems. Guidelines for critical limits, calculation methods and input data. TNO-Report. TNO-MEP-98/376. 

Altenburger, R., Boedeker, W., Faust, M. and Grimme, L.H. (1996) Regulations for combined effects of pollutants consequences from risk assessment in aquatic toxicology, Food and Chemical Toxicology 34, 1155-1157. 

These limitations of the current system of assessing aquatic environment quality indicate that further research and newer, more reliable tools are needed. Such tools introduced into analytical practice would enable fresh information to be obtained. This information would then complement the data obtained from chemical monitoring and would enable the real risk from the presence of a mixture of diverse pollutants in the environment to be adequately assessed. 

Brock TCM, Crum SJH, Deneer JW, Heimbach F, Roijackers RMM, Sinkeldam JA. 2004. Comparing aquatic risk assessment methods for the photosynthesis-inhibiting herbicides metribuzin and metamitron. Environ Pollut 130 403-426. 

Sherratt, T.N. and PC. Jepson. 1993. A metapopulation approach to modeling the long-term impact of pesticides on invertebrates. ]. Appl. Ecol. 30 696-705. Shugart, L.R. 1990. DNA damage as an indicator of pollutant induced genotoxic-ity. In Aquatic Toxicology and Risk Assessment, Vol. 13, ASTM STP-1096, W.G. Landis and W.H. van der Schalie, Eds. American Society for Testing and Materials, Philadelphia, PA, pp. 348-355. 

In Figure 6-1 (from Ahlf Munawar, 1988, after Calamari et al., 1979) the proposed strategy for risk assessment of sediment-associated pollutants is shown. The solid lines indicate the direction of increasing difficulty and specificity of each level. The dotted lines show that at each level, a risk assessment is possible when the results of the test represents either a toxic or hazardous bioconcentration of contaminants. Different types of biological tests have been applied on polluted sediments, either on liquid-phase or water-column effect, and those concerned with effects of solid-bound contaminants, which are ingested by aquatic organisms ... 

Indeed, OCPs, once released into the environment, are distributed into various environmental compartments (e.g., water, soil, and biota) as a result of complex physical, chemical, and biological processes. In order to perform appropriate exposure and risk assessment analyses, multimedia models of pollutant partitioning in the environment have been developed. Properties which are at the base of such a partitioning are water solubility (WS), octanol-water partition coefficient (Ko ), soil adsorption (K ), and bioconcentration factors (BCFs) in aquatic organisms, following these four equilibriums ... 

Fish bioaccmnulation and biomarkers in environmental risk assessment have been reviewed by Oost et al. [360]. Fish bioaccmnulation markers may be applied in order to elucidate the aquatic behavior of enviromnental contaminants and to assess exposme of aquatic organisms. The feasibility of PAH tissue concentrations in marine species as a monitoring parameter for PAH exposme depends on their uptake, biotransformation and excretion rates. Since it remains hard to accmately predict bioaccumulation in marine species, even with highly sophisticated models, analyses of tissue levels are required. The main problem is that PAHs do not tend to accumulate in fish tissues in quantities that reflect the exposme. The analysis of PAH metabolite levels in fish bile can be used to assess the actual PAH uptake, rather than the analysis of the non-hydroxylated PAHs content [328,361]. A number of sentinel fish species have been proposed to asses pollution by PAHs [325,326], as well as several mussels [322,323,326,352]. Several studies have also correlated the high levels of 1-OHPy and B(a)Py metabolites found in the bile of cat-shark with contamination sources such as boat traffic and combustion-based industries present in the sampling area [362]. 

The non-measurable vapour pressure is a reason why ILs are frequently uncritically regarded as inherently environmentally friendly compounds. The loss of ILs is low, so a potential source of air pollution or inhalation is eliminated. Nevertheless, if one does classify ILs as "green" chemicals, questions such toxicity and persistence in the environment must also be addressed. The application of ILs on an industrial scale may p>ose an environmental hazard as a result of their transport, storage, technical breakdown, discharge in wastewaters etc. Therefore, in order to responsibly apply ILs in industrial processes, investigations of their fate and behaviour in the relevant environmental comp>artments (degradation, sorption etc.) and a proper risk assessment of ILs in the soil and aquatic environment (toxicity) must be imdertaken and taken into consideration. The biodegradabihty of ILs, their toxicity and sorption in the environment are also briefly discussed in this chapter. 

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