Toxic to the Aquatic Environment

Substances which decompose slowly in aquatic systems and have a toxic potential, have to be labeled with the R-phrase R 53. 

R 53 May cause long-term adverse effects in the aquatic environment 

LC50 Lethal concentration concentration, with death of half of the fish. 

EC50 Effective concentration concentration, with a specific effect half of the investigated objects, e.g. loss of swimming capability, inhibition of reproduction. 

IC50 Inhibitory concentration concentration, at which half the plants or animals show an inhibition effect, e.g., inhibition of growth. 

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Some competent authorities (CA) may require SDS s to be compiled for mixtures which are not classified for acute toxicity or aquatic toxicity as a result of application of the additivity formula, but which contain acutely toxic substances or substances toxic to the aquatic environment in concentrations equal to or greater than 1 % ... 

Readily biodegradable and has a low potential to bioaccumulate. Not expected to be toxic to the aquatic environment. 

Environmental hazard, water hazard, EH ater This evaluates the process toxicity to the aquatic environment. This indicator corresponds to a hypothetical volume of water polluted per unit mass of desired product. GREENSCOPE employs a set of equations for the calculation of this indicator. A definition of this indicator is given by (refer to Ref [7] for details on this calculation) ... 

There has been a substantial development during the last century to construct molecules that are more efficient than the fatty acid soaps that have been produced for over 2000 years. As pointed out in the chapter on surfactants (Oleochemical and Petrochemical Surfactants An Overall Assessment) in the first book in the series about renewable products Renewables-Based Technology. Sustainability Assessment), most surfactants today are readily biodegradable and low-toxic to the aquatic environment, which are the two criteria for green surfactants . The majority of these surfactants are, however, synthesized from petroleum, which of course is non-renewable. This book will focus on renewable sources for surfactants that are also readily biodegradable and how an increased use of renewable sources might be achieved. 

In several cases, such as shellfish areas and aquatic reserves, the usual water quaUty parameters do not apply because they are nonspecific as to detrimental effects on aquatic life. Eor example, COD is an overall measure of organic content, but it does not differentiate between toxic and nontoxic organics. In these cases, a species diversity index has been employed as related to either free-floating or benthic organisms. The index indicates the overall condition to the aquatic environment. It is related to the number of species in the sample. The higher the species diversity index, the more productive the aquatic system. The species diversity index is computed by the equation K- = (S — 1)/logjg I, where S is the number of species and /the total number of individual organisms counted. 

The Danish EPA has developed an advisory list for self-classification of dangerous substances including 20 624 substances. The substances have been identified by means of QSAR models (Quantitative Structure-Activity Relationship) as having acute oral toxicity, sensitization, mutagenicity, carcinogenicity, and/or danger to the aquatic environment. 

Ammonia is not hazardous to humans and other mammals because the existence of a specific mechanism in their bodies leads to the conversion and excretion of ammonia. However, fish and amphibians lack this mechanism, and as a result ammonia is very toxic and dangerous to the aquatic environment. 

Finally, a recent study was undertaken to assess the human and environmental hazard of recycled tire crumb as ground covering in playgrounds (Birkholz et al., 2003). Here, the PEEP scale was called upon to estimate hazard associated with aquatic exposure to water-soluble extracts of tire crumbs. Based on an initially-determined PEEP value of 3.2 for projected volumes of tire crumb leachates to the aquatic environment and a documented decrease in toxicity three months after tire crumb cover had been in place, the study concluded that tires recycled in this fashion would not present a significant risk of contamination for either receiving surface or groundwaters. 

In brief, the PEEP index is a useful HAS to apply in comparative studies of wastewater effluents to assess their ecotoxicity and toxic loading. Some of its advantages include the fact that it considers results from different toxicity tests and endpoints, while integrating all possible antagonistic, additive or synergistic interactions that can occur between toxicants in a complex liquid sample. Furthermore, the use of a single PEEP value becomes very useful for decisionmakers who are then able to take science-based decisions to prioritize corrective actions on industries whose effluents are the most toxic for the aquatic environment. It is also noteworthy to point out that the PEEP index can be applied anywhere with any number or type of tests and endpoints to suit the needs and expertise of laboratories internationally. 

The harmonized system for classifying chemical substances for the hazards they present to the aquatic environment is based on a consideration of systems existing listed in 4.1.1.7.4. The aquatic environment may be considered in terms of the aquatic organisms that live in the water, and the aquatic ecosystem of which they are part. To that extent, the proposal does not address aquatic pollutants for which there may be a need to consider effects beyond the aquatic environment such as the impacts on human health etc. The basis, therefore, of the identification of hazard is the aquatic toxicity of the substance, although this may be modified by further information on the degradation and bioaccumulation behaviour. 

Figure 4.1.1 Categories for substances hazardous to the aquatic environment Acute toxicity...

Calamari, D. and J.S. Alabaster. 1980. An approach to theoretical models in evaluating the effects of mixtures of toxicants in the aquatic environment. Chemosphere 9 533-538. 

Tinsley, D., Johnson, I., Boumphrey, B., Forow, D. and Wharfe, J. (1996) The use of direct toxicity assessment to control discharges to the aquatic environment in the United Kingdom. In Toxic Impacts of Wastes on the Aquatic Environment, Tapp, J.F., Hunt, S.M. and Wharfe, J.R. (eds), pp. 36-43. Royal Society of Chemistry, London. 

All the plants that have been used for evaluating the effect of toxicants in the aquatic environment (Section 7.3.1.3) are possible candidates—bearing in mind the additional routes of exposure that may be important in the natural environment. Experiments on the toxicity of a range of chlorophenols and chloroanilines to lettuce (Lactuca sativis) revealed a number of important determinants (van Gestel et al. 1996). 

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