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E. W. Schafer

Publications and source records attributed to E. W. Schafer.

5 recordsLinked to original sources
USGS1985

Acute oral toxicity and repellency of 933 chemicals to house and deer mice

Five individual bioassay repellency or toxicity variables were estimated or determined for deer mice ( Peromyscus maniculatus ) and house mice ( Mus musculus ) under laboratory conditions. ALD's (Approximate Lethal Doses) or LD 50 's of 230 chemicals to deer mice are presented, as are food reduction (FR) values (3-day feeding test as a 2.0% treatment rate) for white wheat seeds ( Triticum aestivum ) for 696 chemicals and Douglas fir seeds ( Pseudotsuga menziesii ) for 81 chemicals. A similar repellency evaluation (REP) using a 5-day test with white wheat seeds at a 2.0% treatment rate was conducted with house mice and the results for 347 chemicals are presented. These toxicity and repellency data should be useful to those desiring to predict the potential for acute toxicity in wild mammals following exposure to a wide variety of chemicals. A calculation of the daily chemical dose ingested in mg/kg/day during the wheat test on deer mice and its resultant effects on mortality are also presented for most of the 696 chemicals. This calculated value, when used along with the ALD or LD 50 , should permit a rough estimate of the potential subacute toxicity of any tested chemical on wild mammals for which both types of data are available.

Archives of Environmental Contamination and Toxico↗
USGS1984

Potential primary and secondary hazards of avicides

There are six chemicals or groups of chemicals that are currently registered as avicides that can be used in some or all of the U.S. Most of these chemicals, because of their diverse chemical composition and innate toxicological effects, present somewhat different primary and secondary hazards to avian and mammalian predators and scavengers. Of the chemicals reviewed, all appear to present some degree of primary hazard to non-target birds and mammals; however, PA-14, the Starlicide family of chemicals and fenthion appear to be the least hazardous when used according to use directions. 4-Aminopyridine, endrin and strychnine, because of their high acute toxicity and lack of selectivity, must be considered potentially more hazardous. With respect to secondary hazards, the ranking of chemicals changes considerably and only PA-14 appears to present a negligible hazard. The Starlicide family of chemicals presents negligible hazards to most animal species under currently registered uses, but may be potentially hazardous to cats and owls under specific use conditions. Two chemicals, 4-aminopyridine and strychnine, are potentially more hazardous to predatory and scavenger animals due to their highly toxic nature and rapid lethal effects in target species, leaving unassimilated chemical in the gastrointestinal tract. The remaining chemicals, endrin and fenthion, have been shown to possess the potential for more significant secondary poisoning; however, because of restrictive uses, most of the potential hazards have been avoided in operational use.

Conference Paper↗
USGS1983

The acute oral toxicity, repellency, and hazard potential of 998 chemicals to one or more species of wild and domestic birds

The acute oral toxicity, repellency, and hazard potential of 998 chemicals to one or more of 68 species of wild and domestic birds was determined by standardized testing procedures. Red winged blackbirds were the most sensitive of the bird species tested on a large number of chemicals, and an index based on redwing toxicity and repellency may provide an appropriate indication of the probability of acute avian poisoning episodes. Avian repellency and toxicity were not positively correlated ( i.e. toxicity varied independently with repellency).

Archives of Environmental Contamination and Toxico↗
USGS1974

Hazards to animals feeding on blackbirds killed with 4-aminopyridine baits

Red-winged blackbirds ( Agelaius phoeniceus ) killed by ingesting cracked corn baits treated with 3 percent 4-aminopyridine, or by oral doses of 4-aminopyridine, were fed to canines, laboratory rats ( Rattus norvegicus ), black-billed magpies ( Pica pica ), and three species of hawks. The test animals consumed the equivalent of up to 3.4 LD 50 doses of 4-aminopyridine in single feedings and up to 3.2 LD 50 doses a day for 20 days in repeated feedings. None showed any symptoms of intoxication or gross abnormalities at necropsy.

Journal of Wildlife Management↗