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A general description of a $sup 252$Cf inhalation incident, personnel decontamination and precautionary medical treatment are presented in this paper. Californium urinary excretion was followed, some fecal analyses were carried out and in vivo measurements were made with a 4 x 8-in. NaI(Tl) detector. Bioassay data are evaluated to indicate gastrointestinal and urinary clearance rates. The effects of DTPA chelation and catharsis are discussed. (auth)

This paper reviews recent findings and actions in the United Kingdom concerning lead in tap water and its biological effects, discusses some problems which arise with action to reduce exposure and outlines the limitations in the scientific evidence, with particular emphasis on the evidence concerning neuropsychological effects.

The problem of environmental contamination by toxic substances and human exposure to these substances has attracted increased attention in recent years. Particular concern has centered on polychlorinated biphenyls (PCBs), which have become widespread environmental pollutants as well as contaminants of the human population. This paper reports data from a study of PCB contamination of nursing mothers' breast milk in Michigan. During 1977 and 1978, breast milk samples of 1,057 nursing mothers residing in Michigan were tested for PCB residues. All of the 1,057 samples collected from 68 of the state's 83 counties contained PCB residues ranging from trace amounts to 5,100 parts per million (fat weight basis). The mean level was 1,496 parts per million (ppm), with 49.5 per cent of the samples having PCB levels of 1-2 ppm, 17.4 per cent had 2-3 ppm, and 6.14 per cent had more than 3 ppm. There was no consistent trend in the level of PCB contamination over the 24 months of monitoring. The mean PCB level for the eighth quarter of monitoring was slightly higher than for the first quarter. The public health significance of PCB contamination in human populations and its effects on breast-fed for eight months by a woman with the average PCB level in this sample would have an estimated body burden of approximately 0.89 ppm of PCBs. The implications of PCB contamination of human milk with regard to current breast-feeding practices are discussed and several precautionary measures are recommended.

Hexachlorobenzene (HCB) is a chemical of concern to the US Environmental Protection Agency. Although the use of HCB as a fungicide has virtually been eliminated, detectable levels of HCB are still found in nearly all people in the USA. This paper describes an examination of HCB-residue levels from the US National Human Adipose Tissue Survey, which is an annual programme to collect a nationwide sample of adipose-tissue specimens and analyse them for the presence of toxic compounds. The specimens are collected from surgical patients and autopsied cadavers according to a multistage statistical survey design that allows identification of geographic and demographic subpopulations with elevated HCB levels, and thus may help to indicate sources of human exposure to this chemical. Data on HCB body-burden levels are available for the years 1974-1983, excluding 1980 and 1982. The estimated average residue level of 6115 specimens is 0.053 ppm, the ninetieth percentile value is 0.09 ppm and the range is 'not detected' to 4.33 ppm. The analysis reveals that while the percentage of individuals with detectable levels is increasing, the annual average level is decreasing. A large percentage of specimens with elevated HCB levels comes from the Pacific census division and the oldest age group. In comparison, world-wide detectable levels are approaching 100% and average residue levels tend to increase with age. World-wide HCB levels are higher in females, which contrasts with findings from the National Human Adipose Tissue Survey.

Formulae necessary to relate the quantity of radionuclides excreted to that assimilated in exposures that are acute and those that are multiple or continuous are derived from power function relationships. Particular attention is given to providing equations having variables for which the bioassayer can easily derive numerical values. This paper presents this data.

Ultrasounds and ionizing radiation are extensively used for diagnostic applications in the cardiology clinical practice. This paper reviewed the available information on occupational risk of the cardiologists who perform, every day, cardiac imaging procedures. At the moment, there are no consistent evidence that exposure to medical ultrasound is capable of inducing genetic effects, and representing a serious health hazard for clinical staff. In contrast, exposure to ionizing radiation may result in adverse health effect on clinical cardiologists. Although the current risk estimates are clouded by approximations and extrapolations, most data from cytogenetic studies have reported a detrimental effect on somatic DNA of professionally exposed personnel to chronic low doses of ionizing radiation. Since interventional cardiologists and electro-physiologists have the highest radiation exposure among health professionals, a major awareness is crucial for improving occupational protection. Furthermore, the use of a biological dosimeter could be a reliable tool for the risk quantification on an individual basis.

Current questions about lead exposure focus on the consequences of levels too low to have erupted into blatantly discernible defects. The present paper addresses two sets of interrelated problems derived from this issue. One is how to define the behavioral consequences of asymptomatic lead absorption, and the second focuses on behavioral assessment procedures. Current primary prevention programs emphasize environmental monitoring, and early detection programs emphasize lead body burden measurements. The evaluation of behavioral problems in school children as a function of body burden is rarely performed. Epidemiologic data indicate sufficient natural variability to determine the degree of association between indices of total body burden and behavior. Assessment procedures are described and research suggestions offered that sample concretely defined target behaviors in social environments.