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Biomedical subjects

J A Liddle

Publications and source records attributed to J A Liddle.

At least 37 records · Page 2Linked to original sources
PubMed1980

Metabolic consequences of exposure to polychlorinated biphenyls (PCB) in sewage sludge.

Polychlorinated biphenyls (PCB) were discovered in sewage sludge used for fertilizer in Bloomington, Indiana. The PCB had been discharged into the municipal sewage system by an electrical capacitor manufacturing plant. To study the epidemiology and metabolic consequences of PCB exposure an epidemiologic and clinical survey was conducted. Mean serum PCB levels were 17.4 ppb in 89 sludge users, 75.1 ppb in 18 workers with occupational exposure to PCB, 33.6 ppb in 19 members of those workers' families, and 24.4 ppb in 22 community residents without unusual exposure to PCB. In sludge users PCB levels were associated positively with per cent performance of garden care (p = 0.035) and negatively with wearing gloves while gardening (p = 0.021), but were not significantly associated with the amount of sludge used or the duration of exposure. In no groups were chloracne or systemic symptoms of PCB toxicity noted, nor were significant correlations found between PCB levels and tests of hematologic, hepatic, or renal function. Plasma triglyceride levels increased significantly with serum PCB concentrations in both alcohol drinkers and nondrinkers (r = 0.541, n = 36, p < 0.001 for nondrinkers). These data indicate that PCB may alter lipid metabolism at levels of exposure and bioaccumulation insufficient to produce overt symptoms.

Agriculture↗
PubMed1979

Determination of paraquat in sunflower seeds by reversed-phase high-performance liquid chromatography.

The herbicide paraquat was determined with extracts from 1-g samples of sunflower seeds. The liquid chromatography procedure utilized a microparticle (10 micron) C18 reversed-phase column and isocratic elution with 27% acetonitrile in water, 10 mM in the sodium salt of octanesulfonic acid. Eluted paraquat was detected at 254 and 280 nm and quantitated by paraquat internal standard peak height ratios. This procedure provided linear working curves over the concentration range of 0-20 microgram/g of paraquat. Recovery of paraquat varied from 89-101%, with an average recovery of 93%. Good agreement was obtained in the comparison of results of the described procedure with those from a well established UV procedure.

Chromatography, High Pressure Liquid↗
PubMed1979

A fatal episode of accidental methomyl poisoning.

Three fatalities from the accidental ingestion of methomyl, a carbamate pesticide, are reported. The methomyl had been stored in an unlabeled tin can and was accidentally used in preparing "roti," an Indian dish. The identification of the source of the poison through animal tests and further chemical identification is described. The lethal dose of methomyl was estimated to have been between 12 and 15 mg/kg body weight.

Accidents↗
PubMed1978

Epidemic kepone poisoning in chemical workers.

From March 1974 through July 1975, 76 (56%) of 133 persons who had worked at a pesticide plant that produced Kepone, a chlorinated hydrocarbon insecticide, contracted a previously unrecognized clinical illness characterized by nervousness, tremor, weight loss, opsoclonus, pleuritic and joint pain, and oligospermia. Illness incidence rates for production workers (64%) were significantly higher than for nonproduction personnel (16%). The mean blood Kepone level for workers with illness was 2.53 ppm and for those without disease 0.60 ppm (p less than 0.001). Blood Kepone levels in current workers (mean, 3.12 ppm) were higher than those in former employees (1.22 ppm). Blood Kepone levels for workers in nearby businesses and for residents of a community within 1.6 km of the plant ranged from undetectable to 32.5 ppb. Illness attributable to Kepone was found in two wives of Kepone workers; there was no apparent association between frequency of symptoms and proximity to the plant in the survey of the community population.

Chemical Industry↗
PubMed1978

Identification of some basic extractable compounds produced by Neisseria gonorrhoeae and Neisseria meningitidis in a defined medium.

Electron capture gas-liquid chromatography and mass spectrometry have been used to identify some of the basic extractable heptafluorobutyric anhydride reactive compounds found in a defined medium after 20 h of growth by Neisseria gonorrhoeae and N. meningitidis. Acetoin, 2,3-butanediol, pyrroline, and 1,3-diaminopropane were identified by both gas chromatography and mass spectrometry; 2-hydroxy-pyrrolidine and 3-aminomethyl-pyrrolidine were tentatively identified by mass spectrometry. A possible origin of the amines is through enzymatic oxidation of polyamines.

Acetoin↗
PubMed1978

Persistent liver lesions in rats after a single oral dose of polybrominated biphenyls (firemaster FF-1) and concomitant PBB tissue levels.

In a preliminary study, 12 male and 12 female weanling Sherman strain rats were given a single dose of 1000 mg polybrominated biphenyls (PBBs) FireMaster FF1 Lot 7042 kg/body weight as a 5% solution in corn oil. Three male and three female weanling rats were given corn oil. One day after dosing PBB blood levels ranged from 78 to 162 ppm and 42 days later they ranged from 1.1 to 2.99 ppm. The liver was the only organ with pathological changes. In a long-term recovery study groups of 20 male and female rats, 2 months old, were given 0 or 1000 mg PBBs/kg body weight as a single dose in peanut oil. Five rats per group killed 2, 6, 10, and 14 months after dosing had pronounced liver pathology, including hepatic porphyria in the female rats and neoplastic nodules also mainly in female rats. Chemical analyses of blood, liver, and adipose tissue for PPBs 10 and 14 months after dosing gave the following mean results. Blood levels in females were 2.9 and 2.92 ppm, respectively, and males 0.94 and 1.34 ppm, respectively. Adipose tissue levels in females were 1202 and 783 ppm and in males 713 and 866 ppm, respectively. The liver levels in females were 37 and 22 ppm and in males 60 and 63 ppm, respectively.

Adipose Tissue↗
PubMed1977

Fatal parathion poisoning caused by contamination of flour in international commerce.

In January 1976, 79 persons in Jamaica were acutely poisoned by the organophosphorus insecticide parathion. Seventeen died. Cases occurred in three episodes at separate locations, but all patients had consumed wheat flour from a single lot consisting of 5264 cotton bags. Parathion in concentrations of less than 1 to 9900 ppm was identified in flour from six bags in this lot; three had splash marks. The flour had been milled in Western Europe from European wheat, carried in trucks to a dockside warehouse, and loaded aboard ship after 2-5 days' storage. In Jamaica, the flour had moved from quayside to outbreak locations along separate routes through two import houses. Site inspections and review of shipping records suggested that the likely point of contamination was the European port, where foodstuffs and insecticides were stored in the same warehouse.

Adolescent↗
PubMed1977

Hereditary cholinesterase deficiency: a report of a family with two rare genotypes.

Cholinesterase deficiency was detected in a young girl following an episode of postanesthesia apnea. Subsequently, plasma and serum cholinesterase levels and dibucaine numbers were determined on blood samples from 56 members of her extended family. Including the proband, three individuals were identified with severe cholinesterase deficiency and 12 were found to have mild abnormalities. The occurrence of two genetic variants regulating cholinesterase production, the "silent" gene and the atypical enzyme, is postulated to account for the unusual pattern of inheritance in this family. Screening family members of confirmed cases is essential to prevent the potentially fatal consequences of this hereditary disorder.

Adolescent↗
PubMed1977

Electron capture gas chromatography detection and mass spectrum identification of 3-(2'-ketohexyl)indoline in spinal fluids of patients with tuberculous meningitis.

A basic, extractable, indolic type of compound, which was derivatized with heptafluorobutyric anhydride and pyridine, was obtained from the cerebrospinal fluids of patients with acute tuberculous meningitis. The compound was detected by frequency-pulsed, modulated electron capture gas-liquid chromatography, and it was tentatively identified by mass spectrometry as 3-(2'-ketohexyl)indoline. The compound was found to be valuable for differentiating between tuberculous, cryptococcal, and aseptic meningitides.

Chemical Phenomena↗
PubMed1975

Tetrachlorodibenzodioxin: an accidental poisoning episode in horse arenas.

Tetrachlorodibenzodioxin was identified as the apparent cause of an outbreak of poisoning in humans, horses, and other animals. Exposure was related to the spraying of contaminated waste oil on riding arenas for dust control. The contamination resulted from improper disposal of a toxic industrial waste. The pathologic effects and chemical identification of tetrachlorodibenzodioxin are described.

Aged↗
PubMed1975

Epidemic lead absorption near an ore smelter. The role of particulate lead.

Blood lead levels were determined on a random sample of persons in all age groups living near a lead-emitting smelter in El Paso, Texas. A blood lead level of greater than or equal to 40 mug per 100 ml, which was considered indicative of undue lead absorption, was found in 53 per cent of the children one to nine years old living within 1.6 km of the smelter and in 18 per cent of those from 1.6 to 6.6 km; beyond that distance in older persons levels were lower. Children in the first 1.6 km with blood levels of greater than or equal to mug per 100 ml were exposed to 3.1 times as much lead in dust as children there with lower blood values (6447 vs 2067 ppm). There was also airborne lead exposure (8 to 10 mug per cubic meter, annual mean). Paint, water, food, and pottery were less important as sources. The data suggest that particulate lead in dust and air accounted for most of the lead absorption in El Paso children. The smelter was the principal source of this lead, especially within 1.6km of itself.

Adult↗
PubMedDate not supplied

Epidemiology and pathology of a tetrachlorodibenzodioxin poisoning episode.

We describe epidemiological and laboratory investigation of a poisoning outbreak that involved three riding areas and killed fifty-seven horses, five colts, and numerous other animals. The outbreak was traced to the spraying of the areas with salvage oil contaminated with tetrachlorodibenzodioxin, trichlorophenol, and polychlorinated biphenyls. The contamination of the salvage oil resulted from the improper disposal of toxic industrial waste. In the tissues of the horses available for study, the most prominent lesion was a centrilobular fibrosis of the liver that arose in the wall of the central veins. This lesion resembled the chronic form of veno-occlusive disease of the liver in humans.

Animals↗
PubMedDate not supplied

Amateur radio operators and exposure to polychlorinated biphenyls.

In September, 1982, the Special Studies Branch, Chronic Diseases Division, Center for Environmental Health, Centers for Disease Control, was alerted to the possibility that oils in certain oil-filled devices used by amateur radio operators throughout the country were contaminated with polychlorinated biphenyls (PCBs). To evaluate the possible exposures and concomitant health risks, we conducted an exposure assessment study in two phases: an evaluation of the prevalence of environmental contaminations and an assessment of human exposure. Of 77 oil samples collected, only 2 were contaminated above a 50-ppm level; analyses of blood specimens collected from these two owner-operators showed serum PCB-levels which were well within a "normal" or expected background range. Although, on the basis of these limited data, PCBs from contaminated oils do not appear to be a hazard to amateur radio operators, we recommend that PCB-contaminated oils should not be used because of the continuing potential for exposure from either inhalation or direct contamination.

Adult↗
PubMedDate not supplied

Investigation of hyperkeratotic activity of polybrominated biphenyls in Firemaster FF-1.

A polybrominated biphenyl (PBB) mixture was fractionated by normal-phase preparative high-performance liquid chromatography. The hexane fractions were concentrated and applied to rabbit ears. Only the most polar fraction produced hyperkeratosis on the rabbit ears. This active fraction was subfractionated by using the same procedure. Again, the extent of hyperkeratotic activity increased with increasing polarity. The PBBs of the largest concentration levels in the active fraction were purified by preparative gas chromatography and tested on rabbit ears. The major compounds did not demonstrate hyperkeratotic activity.

Animals↗
PubMedDate not supplied

High performance liquid chromatography of mycotoxin metabolites in human urine.

Because mycotoxins occur worldwide in grain and grain products, evaluating their effects on the health of the population has become important. The development of a high performance liquid chromatographic (HPLC) procedure was investigated for the analysis of aflatoxin B1, citrinin, and ochratoxin A, from hydrolyzed human urine. Solid-phase extraction (SPE) was used for sample clean-up and concentration. Reversed-phase liquid chromatography (RPLC) was used with fluorescence detection for sample analysis. The presence of aflatoxin B1 was confirmed by converting it to the hemiacetal. With 10 mL of urine, the detection limit for aflatoxin B1 and ochratoxin A was in the high parts per trillion (ppt) and that for citrinin was about 10 ppb.

Aflatoxin B1↗