Publications

Factors influencing the uptake of the sodium salt of 2,4-dichlorophenoxyacetic acid (2,4-D), under conditions in which no net metabolism occurred, were investigated in an effort to determine both the significance of “non-metabolic” uptake as a potential agent in reducing pesticide levels and the mechanisms involved. Uptake of 2,4-D was affected by pH, temperature, and the presence of...

The insecticidal properties of rotenone and pyrethrum have been known for many years. Both toxicants have long histories of extensive use for control of a variety of insect pests. Rotenone has been also employed as a management tool by fishery biologists to rehabilitate fishing waters, and its toxicity to fish in a number of ecological situations is well established. Pyrethrum's toxicity...

Cutthroat trout were periodically exposed to p, pp-DDT, in acetone solution or in the food. Excessive mortality occurred only in lots treated with high concentrations of DDT, probably as a result of decreased resistance to nonspecific stressors. Surviving fish in these lots were significantly larger than those in the control lot, or in the lots treated with low concentrations of DDT. The...

Labeled DDD [ 1,1-dichlor-o-2,2-bis(p-chlorophenyl)-ethane] was formed from C14-labeled DDT in the presence of yeast. The formation of DDD from DDE [1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene] was not observed, indicating that a reductive dechlorination of DDT occurs.

A farm pond near Morrison, Colorado, was treated with 0.02 p.p.m. of DDT in June 1961. The persistence and distribution of the insecticide in materials sampled from the aquatic environment were studied until November 1962. Detectable amounts of DDT were not found in the water after 3 weeks. Residues in the mud had declined within 8 weeks after the treatment to levels not significantly...

While studying the effects of pesticides on fish and their environment for the Bureau of Sport Fisheries and Wildlife, I have developed a soil sampler that will collect a thin uniform layer of sediment from pond and stream bottoms. As it is becoming increasingly important to analyze the residual deposits of pesticides in this shallow layer of soil in aquatic environments, it seems useful...

Plastic film have been used by fishery workers as barriers to subdivide experimental ponds in order to assess the value of some chemical treatment, and as test vessels to contain dilute solutions or suspensions of toxic chemicals in experiments conducted to establish tolerance levels of these chemicals for fish.

The introduction of artifacts from vessels, materials, and chemicals is a serious problem in the study of pesticide residues. It is therefore of interest to record findings that polyethylene wash bottles contain substances soluble in organic solvents and reactive with the silver nitrate chromogenic spray commonly employed in the paper chromatographic analysis of chlorinated organic...

Carboxylic esters and lactones react with alkaline hydroxylamine to yield hydroxamates; these in acidic solution form colored iron(III) complexes. A photometric determination of such esters and lactones is thus permitted and has been extensively applied ( I-6). Hestrin ( 3) utilized this method for the microdetermination of acetylcholine and his procedure is much used for the in vitro...

The fate of toxaphene, applied in three treatments at a total calculated concentration of 0.05 p.p.m. to Clayton Lake, New Mexico, was followed over a 1.5-year period. A detailed description of the chromatographic method of analysis is given. Water concentrations of toxaphene were higher in leeshore samples than in windward samples for 2 weeks after the application; toxaphene levels then...

The growing impetus of studies on fish and pesticides focuses attention on the need for standardized reporting procedures. Good methods have been developed for laboratory and field procedures in testing programs and in statistical features of assay experiments; and improvements are being made on methods of collecting and preserving fish, invertebrates, and other materials exposed to...

The effects of pesticides on fish have become improtant to fish conservation since World War II, when DDT first came into common use. With the development of other potent insecticides and the increasing use of massive dosages in more recent years, the threat to fish and fish foods has increased. Fishery biologists have conducted some studies on the effects of insecticides, but it has...