Sublethal effects of silver in zooplankton: Importance of exposure pathways and implications for toxicity testing

2001 ◽  
Vol 20 (3) ◽  
pp. 568-574 ◽  
Author(s):  
Sharon E. Hook ◽  
Nicholas S. Fisher
Keyword(s):  
Sublethal Effects ◽  
Toxicity Testing ◽  
Exposure Pathways

Effectiveness of a Secondary Impoundment System in Reducing Industrial Wastewater Toxicity

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2349-2352 ◽  
Author(s):  
A. Khan ◽  
D. Kent ◽  
J. Barbieri ◽  
S. Khan ◽  
F. Sweeney
Keyword(s):  
Industrial Wastewater ◽  
Chronic Toxicity ◽  
Sublethal Effects ◽  
Aquatic Toxicity ◽  
Toxicity Testing ◽  
First Year ◽  
Wastewater Discharge ◽  
Cladoceran Species ◽  
Second Year ◽  
Growth And Reproduction

Aquatic toxicity testing was employed over a three year period to test the effectiveness of a secondary impoundment system in reducing biological toxicity of an industrial wastewater discharge. A two tiered approach was used to determine the effects of the wastewater on two cladoceran species, Daphniamagna and Ceriodaphniadubia, and two sensitive life stages of a vertebrate, Pimephalespromelas. Endpoints measured were both acute (lethality) and chronic (growth and reproduction). Results from the first year of testing, conducted on wastewater collected from the inflow to the secondary impoundment system, indicated both lethal and sublethal effects. Results from the second year of testing, conducted on the outflow of the secondary impoundment system, showed reduced chronic toxicity and complete absence of acute toxicity. Minor modifications were made to the existing treatment system and toxicity testing was conducted for the second consecutive year on the outflow of the secondary impoundment system. Results from the third year of testing showed no acute or chronic toxicity, indicating improved wastewater treatment.

Toxicity testing of sublethal effects of dredged materials

1988 ◽  
Vol 17 (3) ◽  
pp. 381-389 ◽  
Author(s):  
Raymond W. Alden ◽  
Arthur J. Butt ◽  
Robert J. Young
Keyword(s):  
Sublethal Effects ◽  
Toxicity Testing ◽  
Dredged Materials

Examining Sublethal Effects of Anticoagulant Rodenticides on Haemosporidian Parasitemia and Body Condition in Migratory Red-Tailed Hawks

2019 ◽  
Vol 53 (4) ◽  
pp. 402 ◽  
Author(s):  
Laura A. Kwasnoski ◽  
Kristina A. Dudus ◽  
Allen M. Fish ◽  
Emily V. Abernathy ◽  
Christopher W. Briggs
Keyword(s):  
Body Condition ◽  
Sublethal Effects ◽  
Anticoagulant Rodenticides

SPECIAL PROBLEMS IN TOXICITY TESTING OF LONG ACTING DEPOT CONTRACEPTIVES

1974 ◽  
Vol 77 (1_Suppla) ◽  
pp. S315-S354 ◽  
Author(s):  
F. Neumann ◽  
R. von Berswordt-Wallrabe ◽  
W. Elger ◽  
K.-J. Gräf ◽  
S. H. Hasan ◽  
...  
Keyword(s):  
Biological Effects ◽  
Histological Finding ◽  
Toxicity Testing ◽  
Prolactin Secretion ◽  
List Type ◽  
Human Species ◽  
Prolactin Plasma Level ◽  
Human Use ◽  
Long Acting ◽  
Reproductive Processes

ABSTRACT Two types of so-called "depot contraceptives", long-acting steroids which are of interest for human use, were studied in animals. Norethisterone oenanthate, mainly gestagenic in the human and other species, turned out to be predominantly oestrogenic in rats. This oestrogenicity caused indirectly, via an enhanced hypophysial prolactin secretion, the well-known hypophysial and mammary tumours in rats. Another synthetic gestagen, 4,6-dichloro- 17- acetoxy- 16α-methyl-4,6-pregnadiene-3,20-dione, which might be considered in its biological actions similar to preparations containing chlormadinone acetate or medroxy-progesterone acetate, induced no signs of oestrogenicity in dogs. It is surmised that its gestagenic influence indirectly, and probaby, via an enhanced hypophysial prolactin secretion caused "mammary nodules" in this "non-rodent" species. These studies have born out mainly two facts: A synthetic steroid, norethisterone oenanthate, exerted different biological effects in different species: it was a gestagen in the rabbit, whereas in rats, its predominant influence was oestrogenic. The hypophysial prolactin secretion was enhanced in various species by different mechanisms: in rats, the oestrogenicity caused an increased prolactin plasma level, whereas in dogs, a gestagen with obviously no inherent oestrogenicity, 4,6-dichloro-17-acetoxy-16α-methyl-4,6-pregnadiene-3,20-dione, converted the histological appearance of the anterior pituitary into a condition with a greatly increased number of eosinophils. This histological finding was interpreted as an indicator for a hypersecretion of prolactin. Hence, animal work with "gestagens" has only limited predictive value with respect to their possible effects in the human species. Therefore, inflexible recommendations are not helpful in solving the safety problem of long-acting steroids which affect primarily reproductive processes.

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