Introduction to ENVIRONMENTAL TOXICOLOGY Impacts of Chemicals Upon Ecological Systems - CHAPTER 3 pot

... repeatable laboratory data to effects upon the systems that environmental toxi- cology tries to protect is often called the lab -to- field dilemma. Comparisons of laboratory data to field results ... respect to: SAS default SAS log 10 ASTM 1 (4.0) Dose 4.00 (3. 88–4.12) 3. 80 (3. 59–4.02) 3. 80 (3. 58–4.02) Log 10 dose 4.11 (4.01–4.21) 3. 99 (3. 90–4.10) 3. 99 (3. 90–4.10)...

Ngày tải lên: 10/08/2014, 20:20

... thermophila Tt DFPase-1 80,000 1.12 2.5–4.0 + Tt DFPase-2 75,000 1.26 2.0 + Tt DFPase -3 72,000 0.71 1.7–2.5 + Tt DFPase-4 96,000 1.95 17 30 nt R. cuneata Rc opa-1 19 35 ,000 nt 1 — Rc opa -3 82– 138 ,000 nt ... able to hydrolyze DFP, dichlorvos and dimethyl 2,2,2-trichloro-1-n-butyryloxyethyl phosphonate (butonate). Catfish enzymes also were able to hydrolyze paraoxon and methyl 3- hyd...

Ngày tải lên: 10/08/2014, 20:20

... in toxicant concentrations or interspecific inter- actions. The range of scales important in environmental toxicology range from the few angstroms of molecular interactions to the hundreds of ... responsible for © 1999 by CRC Press LLC CHAPTER 2 A Framework for Environmental Toxicology Environmental toxicology can be simplified to the understanding of only three fu...

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... components of the microcosm com- munity. The protocol requires two species of single-celled green algae or diatoms, one species of filamentous green alga, one species of nitrogen-fixing blue-green alga, ... importance of iden- tifying the specific clone used in toxicity testing when attempting to compare results. Algal 96-H Growth Toxicity Test The purpose of this toxicity test...

Ngày tải lên: 10/08/2014, 20:20

... liver to 25-hydroxy-D 3 . This is then converted in the kidney to 1,25-dihydroxy-D 3 , the “hormone-like” substance that is the active form of the vitamin. The 25-hydroxyla- tion of cholecalciferol ... challenge in the study of both toxicology and Table 6 .3 Effect of CHCl 3 Exposure on Death Rate of Various Strains of Male Mice Strains Death rate (%)...

Ngày tải lên: 10/08/2014, 20:20

... amounts to 15 to 25 mg/day and represents two-thirds of the total absorbed Pb. By contrast, about 20 to 40% of the inhaled Pb is absorbed, amounting to about 8 mg/day, or one-third of the total absorbed ... Nature 268: 7 3- 7 4. Tephly, T.R., G. Wagner, R. Sedman, and W. Piper. 1978. Effects of metals on heme biosyn- thesis and metabolism. Fed. Proc. 37 : 3 5 -3...

Ngày tải lên: 10/08/2014, 20:20

... of the Ecological Effects of Toxicants INTRODUCTION This chapter deals with perhaps the most difficult topic in environmental toxi- cology, how to measure and then evaluate the impact of toxicants ... toxicants at ecological levels of organization. The chapter starts with an evaluation of methods and ends with a discussion of the responses of ecosystems to chemi...

Ngày tải lên: 10/08/2014, 20:20

... Relationship between two toxicity endpoints such as the NOAEL and the EC 50 . 3. Laboratory -to- field extrapolation — Relationship of the estimate of toxicity gath- ered in the laboratory to the effects ... Relationship of toxicity data from one species to another or perhaps more often, class to class. Often only a 96-h green algal toxicity test is available to use as a rep...

Ngày tải lên: 10/08/2014, 20:20

... (ERL-D-SOP- CTI-016), Chironomus tentans (ERL-D-SOP-CTI-015), and Lumbriculus variegatus (ERL-D-SOP-CTI-017), U.S. Environmental Protection Agency, Environmental Research Laboratory, ... Ministry of Environ- ment, Lands, and Parks, Province of British Columbia, B.C., pp. F-1 to F- 13. BCEPD. 1994c. Appendix 3: SEAM laboratory codes. British Columbia Environmental Lab-...

Ngày tải lên: 10/08/2014, 20:20

... analytical toxicology, (2) aquatic toxicology, (3) biochemical toxicology, (4) clinical toxicol- ogy, (5) ecotoxicology, (6) environmental toxicology, (7) epidemiological toxicology, (8) genetic toxicology, ... synergistic effects.r 3. 2.1 HISTORY OF TOXICOLOGY What is toxicology? What is the history of toxicology? What is the importance of toxicology to modern societ...

Ngày tải lên: 18/06/2014, 22:20