Toxicity aquatic

Usually aquatic toxicity of chemicals with general narcosis mechanism of action is described by the octanol/water partition coefficient [73]. However, log is a composite descriptor which has components of molecular volume and H-bond acceptor terms. Raevsky and Dearden [74] therefore used molecular polarizabihty (as a volume-related term) and the H-bond acceptor factor instead of log to model aquatic toxicity (log LC50) to the guppy for 90 chemicals with general narcosis mechanisms. This excellent correlation has statistical criteria better than that obtained for the same data using log Pofy,  

This investigation was supported by the International Sdence Technology Center (project 888) and the Russian Ministry of Education Sciences (contract 02.434.11.1014). The author is very grateful to Drs. J. W. McFarland (Reckon, USA), H. Van de Waterbeemd (AstraZeneca, UK) and K.-J. Schaper (Borstel Research Center, Germany) for collaboration and very useful discussions, and Professor Dr. R. Mannhold for valuable editorial remarks and advice. 

1 Kubinyi, H. Hydrogen bonding, the last mystery in drug design In Pharmacokinetic Optimization in Drug Research, Testa, B., Van de Waterbeemd, H., Folkers, G., Guy, R. (eds.), Wiley-VCH, Weinheim and VHCA, Zurich, 2001, pp. 513-524. 

2 Testa, B., Kier, L. B. The concept of molecular structure in structure-activity relationship studies and drug design. Med. Res. Rev. 1991, 11, 35 8. 

3 Raevsky, O. A. Quantification of non-covalent interactions on the basis of the thermodynamic hydrogen bond parameters./. Phys. Org. Chem. 1997, 10, 405 13. 

Eor the aquatic toxicity test it should be noted that according to REACH The study does not need to be conducted if there are mitigating factors indicating that aquatic toxicity is unlikely to occur, for instance, if the substance is highly insoluble in water or the substance is unlikely to cross biological membranes (i.e., it has a low BCE, authors note) . 

The choice to perform a short- or long-term toxicity test mainly depends on the 

---

For the sample search on aquatic toxicity of atrazine, 1459 results were found. An excerpt on the daphnia acute aquatic toxicity tests (EC50. LC.50) is prc.scnted in Figure 5-33. 

Spill Disposal In treatment of spills or wastes the suppression of vapors is the first concern and the aquatic toxicity to plants, fish, and microorganisms is the second. Normal procedures for flammable Hquids should also be carried out. 

The aquatic toxicity (TLm96) for glycerol is >1000 mg/L (27), which is defined by NIOSH as an insignificant hazard. 

Vegetable and seed oils as well as some synthetic base stocks present a new class of biodegradable base stocks. These fluids (10) have excellent biodegradation properties as measured by criteria developed by the Environmental Protection Agency (EPA) or Organization of Economic Cooperation and Development (OECD). OECD 301 and EPA 560/6-82-003 measure the biodegradation of lubricants. These tests were developed to measure the degradation of oil, especially two-cycle ok, on waterways. Aquatic toxicity criteria toward fish is also found to be acceptable for this class of fluids as measured by EPA 560/6-82-002 and OECD 203 1-12. 

Aquatic Toxicity. The standard tests to measure the effect of substances on the aquatic environment are designed to deal with those that are reasonably soluble ia water. Unfortunately this is a disadvantage for the primary phthalates because they have a very low water solubiUty (ca 50 p.g/L) and this can lead to erroneous test results. The most common problem is seen ia toxicity tests on daphnia where the poorly water-soluble substance forms a thin film on the water surface within which the daphnia become entrapped and die. These deaths are clearly not due to the toxicity of the substance but due to unsuitable test design. 

Aquatic toxicity is reported in mg/L for Pimepha/espromealas (fathead minnow), 69-h LC q 7650 (17) for Daphnia magna (water flea), 48-h EC q 3310 (18) for Mjriophjllum spicatum (water milfoil), phytotoxicity (EC q for growth) 5962 (19) and for Pana breviceps (frog), no observed effect concentration (NOEC) 400 (20). LC q and EC q are lethal and effect concentrations, respectively, for 50% of the subjects tested. 

Aquatic toxicity is becoming (ca 1997) a permit requirement on all discharges. Aquatic toxicity is generally reported as an LC q (the percentage of wastewater which causes the death of 50% of the test organisms in a specified period ie, 48 or 96 h, or as a no observed effect level (NOEL), in which the NOEL is the highest effluent concentration at which no unacceptable effect will occur, even at continuous exposure. 

Approximately one-half of the organics removed are oxidized to CO2 and H2O, and one-half synthesized to biomass. Three to 10 percent of the organics removed result in soluble microbial products (SMP). The SMP is significant because it causes aquatic toxicity. 

Human toxicity, aquatic toxicity, and the environmental impact of engine coolants and deicing fluids ate typically measured on the fresh fluid only. Spent fluids contain varied contaminants that can drastically affect the toxicity and environmental impact of the fluid. Most pronounced is the impact of heavy-metal contaminants in spent antifreeze. Data on spent and recycled antifreeze, compiled by the ASTM Committee on Engine Coolants, show an average lead level 11 ppm, as weU as various other metal contaminants (iron, copper, zinc) (18). The presence of these contaminants in a used fluid may require special disposal techniques for the fluids. 

As computing capabiUty has improved, the need for automated methods of determining connectivity indexes, as well as group compositions and other stmctural parameters, for existing databases of chemical species has increased in importance. New naming techniques, such as SMILES, have been proposed which can be easily translated to these indexes and parameters by computer algorithms. Discussions of the more recent work in this area are available (281,282). SMILES has been used to input Contaminant stmctures into an expert system for aquatic toxicity prediction by generating LSER parameter values (243,258). 

AQUIRE - Aquatic Toxicity Information Retrieval Database... 

R. J. Larson and A. W. Maki, Aquatic Toxicity and Hazard Assessment, ASTM Technical Publication 766, Philadelphia, 1982, p. 120. 

In a continuous model river test system it can be shown that after passage through a sewage treatment plant ester sulfonates have no significant influence on the qualitative and quantitative composition of the biocenosis of a receiving water [113]. All the investigations into the environmental fate of a-sulfo fatty acid esters demonstrate that aquatic toxicity is alleviated by their fast ultimate biodegradability, which allows them to be classified as environmentally compatible. 

Phosphonates are often used in detergents as stabilizers for encymes and bleaching components in a concentration of <0.5%. Dates of acute aquatic toxicity of the most used substances HEDP, aminotrismethylenephosphonic acid (ATMP), and EDTMP are given in Table 14. In a concentration of <2 mg/L no remobilization of heavy metals from sediments was observed [207]. 

Weston DP, Holmes RW, You J, Lydy MJ (2005) Aquatic toxicity due to residential use of pyrethroid insecticides. Environ Sci Technol 39(24) 9778-9784... 

Barry Ml, Logan DC. 1998. The use of temporary pond microsms for aquatic toxicity testing direct and indirect effects of endosulfan on community structure. Aquat Toxicol 41 101 -124. 

Solomon, K.R., Giddings, J.M., and Maund, S.J. (2001). Probabilistic risk assessment of cotton pyrethroid.I. Distributional analysis of laboratory aquatic toxicity data. Environmental Toxicology and Chemistry 20, 652-659. 

Aquatic Toxicity. This is the sum of the toxicity factor of a particular emission multiplied by the amount. Since the factors have only been... 

Human Toxicity Potential. As for aquatic toxicity, the database for human toxicity potential is still being established but is based on acceptable daily doses. The total potential is the sum of potentials released to different media. 

Ecological Acute and chronic aquatic toxicity Adverse reproductive effects on wildlife Phytoxicity... 

Substances with very high acute mammalian toxicity Substances with very high acute or chronic aquatic toxicity Neurotoxins... 

For each chemical class, a set of 4-7 key attributes were identified that can be used to differentiate a chemical from others in the same class. These may include biodegradability, aquatic toxicity, sensitization potential, renewable resource derived, and so forth. Each attribute was selected to be ... 

---