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1. 1. The xerophilous harvester ant Veromessor pergandei produces primarily benzaldehyde in its mandibular glands. 2. 2. This aldehyde, not isolated previously from insects, functions as an effective defensive secretion. 3. 3. A minor constituent, produced by the mandibular glands, functions as a releaser of alarm behavior.

Although the use of arsenical herbicides in both crop and non-crop areas has been widely accepted, the use of certain formulations of these chemicals may have a disastrous effect on wildlife. The following incident emphasizes the sometimes tragic effects of the indiscriminate use of these herbicides by qualified and/or non-qualified persons.

An epidemic with two deaths occurred in a nursery in St. Louis after the use of pentachlorophenol as a mildew preventive with the laundry detergent. Samples of blood, urine, tissue, and clothing from the nursery were extracted with ethyl ether. The ether solution was extracted with 5% sodium hydroxide; the basic solution was acidified and then extracted with benzene. The benzene solution was analyzed by electron capture gas chromatography, using a 3% diethylene glycol succinate column with 2% sirupy phosphoric acid on 60-80 mesh Chromosorb G. Pentachlorophenol was found in the samples in sufficient quantity to account for the epidemic. The presence of pentachlorophenol was confirmed by gas chromatogrifplryrmass spectroscopy and by thin layer analysis.

In the process of investigation of several commercial preparations and formulations of pesticides and pesticide related compounds for contaminants this laboratory observed interesting evidence of ortho-para substituent effects in aryl systems. The subStituent of interest among these compounds is chlorine. The effect of the ortho-para aryl substituent was observed in the mass spectrometric fragmentation patterns. The compounds examined were phenyl ether, octach10rodiphenyl ether, 2,7-dichlorodibenzo-p-dioxin, 2,3,7,8-tetrach10rodibenzo-p-dioxin, octachlorodibenzofuran, octachlorodibenzo-p-dioxin and dibenzofuran.

Five pregnant women were studied for chlorinated hydrocarbon insecticide residues in their blood and milk. Blood samples were obtained from each between 30 days of pregnancy and 115 days postpartum. Three milk samples were collected from each between three and 96 days postpartum. Sample extracts of plasma and milk were analyzed by electron-capture gas-liquid chromatography for chlorinated hydrocarbon insecticides. Eight chlorinated insecticides were detected. The concentrations of these compounds in plasma were within the lower part of the range previously reported for nonpregnant women. A small but statistically significant decrease in the plasma concentration of p,p’-DDT, p,p’-DDE, o,p’-DDE, p,p’-DDD, and total BHC was observed one to six days postpartum. The concentration of the detected compounds in milk varied greatly among the individual women but was within the range reported by others.

Clinical symptoms and gross autopsy findings in two cases of dieldrin poisoning are presented. Studies in one child suggest that redistribution of the insecticide into fat is slow and that the more rapid redistribution of dieldrin is from brain to muscle, which may account for termination of seizures. Concentrations fall to population levels with a first-order decay rate which had, in this case, a half-life of 50 days. Electroencephalograms, helpful for diagnosis, may reflect the brain load of poison. Evidence for liver toxicity was found both acutely and more than one year after poisoning.

A discussion of the dictionary definition of the word meat is presented. It is part of a rebuttal of a criticism of a paper on the relevance of current standards for mercury contamination of food. Incidences of mercury poisoning in humans by ingestion of contaminated food are briefly discussed. 2 references.

Hexachlorophane is widely used as Summary an antibacterial agent. It has been reported that repeated high oral doses of hexachlorophane (25 mg. per kg. per day) in rats produced paralysis and a pronounced œdema of the white-matter of the central nervous system. To see whether hexachlorophane may be absorbed through the intact infant skin, its concentration in the blood of the umbilical cord of fifty infants and in the blood of the same infants obtained on discharge from hospital was determined by gas chromatography. While in the hospital the infants were washed several times with hexachlorophane solutions to prevent staphylococcal infections. The range of hexachlorophane levels in the umbilical cord was 0·003-0·182 p.p.m. (μg. per g.), with a mean of 0·022 p.p.m., and for the blood at the time of discharge from the hospital 0·009-0·646 p.p.m., with a mean of 0·109 p.p.m. It is suggested that infants' skin be rinsed after the use of hexachlorophane.

A metabolite of DDT, 2,2-bis(p-chlorophenyl)ethanol, is a substrate of crystalline liver alcohol dehydrogenase. The oxidation of the substrate was detected spectrophotometrically. The p-nitrophenylhydrazone derivative of the product, 2,2-bis(p-chlorophenyl)acetaldehyde, was identified by comparing its mass spectrum and thin-layer chromatographic behavior with that of an authentic sample.