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At least 937 records · Page 52Linked to original sources
USGS1976

Organochlorine residues in females and nursing young of the big brown bat (Eptesicus fuscus)

Carcasses and brains of 18 big brown bats from Gaithersburg, Maryland, were analyzed for residues of organochlorine insecticides and PCB's. Eleven bats were adult females, and six of these had seven nursing young associated with them....Young bats resembled their parents in microgram amounts of PCB and DDE present in carcasses. However, concentrations of chemicals (expressed as ppm) were significantly higher in young. Brains of three young contained detectable residues of PCB and DDE....Younger adult females contained higher levels of PCB and DDE than did older ones. However, among the oldest females, amounts appeared to begin rising again. This pattern resembles that in free-tailed bats from Bracken Cave, Texas, but differs from the continuous linear decline seen in a Laurel, Maryland population of big brown bats, in which initial levels among younger females were higher than those in the Gaithersburg population....DDE was transferred from female to young more readily than was PCB by nursing. Five of 51 neonate big brown bats from the Laurel population were thought to have been born dead because of residues of PCB that were transferred across the placenta. Present data show that even greater amounts of PCB may be transferred to young by lactation and nursing.

Bulletin of Environmental Contamination and Toxico↗
USGS2013

Residues in common flicker and mountain bluebird eggs one year after a DDT application

Common flicker ( Colaptes auratus ) and mountain bluebird ( Sialia currucoides ) eggs were examined 1 year after DDT application and showed a marked difference. Residue levels in mountain bluebird eggs were approximately 10 times higher than in common flicker eggs (5.29 to 0.58 ppm wet weight). These differences can be explained by disparate dietary habits. The mean level in American kestrel ( Falco sparverius) eggs collected in the spray area at the same time was 6.42 ppm wet weight.

Bulletin of Environmental Contamination and Toxico↗
USGS1991

Acute toxicities to larval rainbow trout of representative compounds detected in Great Lakes fish

In recent years the National Fisheries Research Center-Great Lakes has ranked the potential hazard to fish and invertebrates of various chemical compounds detected in two Great Lakes fishes-- lake trout, Salvelinus namaycush , and walleye, Stizostedion vitreum vitreum (Hesselberg and Seelye 1982). This hazard assessment has included the identification of the potential sources of the compounds, determination of the occurrence and abundance of the compounds in Great Lakes fish, and the determination of acute toxicities of representative compounds of 19 chemical classes (Passino and Smith 1987a). In further studies Smith et al. (1988) focused on 6 of the 19 classes of compounds using the zooplankter Daphnia pulex as the test organism. They ranked the six classes as follows (in decreasing order of toxicity): polycyclic aromatic hydrocarbons (PAHs), alkyl halides, nitrogen-containing compounds, cyclic alkanes, heterocyclic nitrogen compounds, and silicon-containing compounds.

Bulletin of Environmental Contamination and Toxico↗
USGS1989

Pesticide contamination of endangered gray bats and their food base in Boone County, Missouri, 1982

Gray bat guano from Devil's Icebox and Hunters Caves contained dieldrin at levels previously associated with gray bat mortality. Two of four gray bats found dead in Holton Cave had lethal brain concentrations of dieldrin. Twenty-five of 28 (86%) insect samples from bat foraging areas contained measurable dieldrin, heptachlor epoxide or both. Beetle samples were most heavily contaminated containing up to 2.2 ppm and 1.1 ppm heptachlor epoxide. The addition of Holton Cave brings to five the number of Missouri caves where gray bats have died of food chain pesticide poisoning.

Missouri↗
USGS1990

Pesticide and PCB residues for loggerhead shrikes in the Shenandoah Valley

The decline in loggerhead shrike ( Lanius ludovicianus ) populations is widespread and coincides with the use of organochlorines that began in the late 1940's and increased until the 1970's (Morrison 1981; Robbins et al. 1986; Tate 1986). An inhabitant of farmland areas, loggerhead shrikes prey on invertebrates and small vertebrates (Bent 1950), and thus risk exposure to pesticides and other agricultural chemicals. The role of contaminants in the decline of loggerhead shrikes has only been partially assessed (Busbee 1977; Anderson and Duzan 1978; Morrison 1979; Rudd et al. 1981). Studies of the nesting and winter ecology of loggerhead shrikes (Luukkonen 1987; Blumton 1989) during 1985-88 in the Shenandoah Valley, Virginia provided the opportunity to collect eggs and carcasses for contaminant residue analysis. In this paper we provide pesticide and polychlorinated biphenyl (PCB) residue data for eggs and carcasses collected.

Shenandoah Valley↗
USGS1982

Seasonal brain acetylcholinesterase activity in three species of shorebirds overwintering in Texas

There was no seasonal variation in average brain AChE activity for the 3 species of wild birds collected between October and February. Further work needs to be done, however, covering an even broader time frame which includes the reproductive cycle. It appears that some birds feeding at the mouth of an agricultural drain, at some distance from the nearest pesticide applications, were affected by AChE inhibitors.

Bulletin of Environmental Contamination and Toxico↗
USGS1979

Organochlorine residues in eggs of the endangered American crocodile (Crocodylus acutus)

Most of the 27 species and subspecies of surviving crocodilians have declining populations and 22 of them are considered to be severely endangered (IUCN 1971). The United States population of the American Crocodile is no exception; it probably numbers between I00 and 300 individuals (OGDEN 1976). Nests of the species have been regularly surveyed by the staff of Everglades National Park. Our sample consists of eggs that remained in nests after the hatching of broods and of one clutch laid in captivity by an unmated female. Analysis of these samples for organochlorine contaminants has permitted a detailed examination of their contaminant loads and has allowed comparisons with a small sample analyzed in 1972 (OGDEN et al. 1973).

Florida↗