Evaluation of the k(0)-Method by its Application to (n, γ) RNAA of Geological, Environmental and Clay Reference Materials

The k(0)-standardization method, the present state-of-the-art of which is shortly reviewed, is applied to multi-element reactor neutron activation analysis of (standard) reference materials. The analyses are performed independently at the Institute for Nuclear Sciences (Gent, Belgium) and the Central Research Institute for Physics (Budapest, Hungary). Results are given for USGS G-2 (granite), NBS SRM-1633a (coal fly ash) and FCG (fired clay of Gent). Comparison with literature data shows that the k(0)-method, while being experimentally simple, versatile and suited for computerization, offers a potential accuracy of better than 5%

Non-occupational lead exposure and hypertension in Pakistani adults

Hypertension is one of the most prevalent diseases in the developed and developing countries. Based on the long historical association and the provocative findings of blood pressure effects at low level of lead exposure a study was carried out to determine if an association existed between low blood lead concentration and hypertension. In this study the effects of low-level exposure to lead on blood pressure were examined among 244 adults using atomic absorption spectrometer. For quality assurance purpose certified reference materials i.e., Animal blood A-13, Bovine liver 1577 and cotton cellulose V-9 from IAEA (International Atomic Energy Agency) and NIST (National Institute of Standard Technology) were analyzed under identical experimental conditions. The mean age of hypertensive adults was 52 years (range 43~66). The mean values of systolic and diastolic blood pressure were (209±11.7) (range 170~250) and (117±3.9) (range 105~140) mmHg respectively. Blood lead concentration ranged from 78~201 µg/L with a mean of 139 µg/L and 165~497 µg/L with a mean of 255 µg/L in normal and hypertensive adults respectively. Increase in systolic blood pressure was significantly predictive with increase in blood lead levels. Body mass index (BMI) and lipid profile including total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol and triglyceride correlated with blood pressure