Determination of trace elements status of Nigerians with sickle cell anaemia using INAA and PIXE.

The clinical application of trace elements in the management of Sickle Cell Anaemia (SCA) has not become standard recommended practice despite decades of research. A major reason for this is the ambivalence in published results as to the relative importance of some of these elements in the disease. An attempt has been made in this work to correct some of the various factors that could contribute to such inconsistencies. Results from separate investigations carried out on Nigerian subjects by our group, using both INAA and PIXE methods have been holistically evaluated and compared. Trace and minor elements were determined in wholeblood, erythrocytes, plasma, headhair and nail obtained from SCA patients in steady state and compared with identical samples from normal controls. Twelve elements were determined in blood while 20 and 30 elements were analysed in nail and hair samples respectively from the total 225 subjects. The results indicate a general mild zinc deficiency, more serious for males, in Nigerian SCA patients. It is clear that the elements Na, K, Rb and Br play key roles in maintaining homeostasis in the steady-state SCA patients. Possible gender influence in the utilization of K, Br and Fe in SCA is also suggested.

Elemental analysis of blood of Nigerian hypertensive subjects.

Proton-induced X-ray emission (PIXE) has been used to obtain the concentrations of 11 elements (P, S, Cl, K, Ca, Fe, Cu, Zn, Br, Rb, and Cd) in whole-blood samples of 16 hypertensive subjects (mean age: 52.5 +/- 0.5 yr) and 18 age-matched controls (mean age: 51.5 +/- 0.5 yr) in a Nigerian population. The results of the study indicate that the hypertensive subjects have significantly higher mean concentration of Cl, Cd, Cu, and Zn when compared with the controls, and the mean concentration of P, K, and Ca was found to be significantly lower in the hypertensive group in comparison to the controls. Furthermore, the Zn:Cd ratio was found to be significantly higher in the controls than in the hypertensives, and the Cu:Zn ratio was significantly higher in the hypertensives.

Trace elements in drinking and groundwater samples in southern Nigeria.

The levels of Al, Sn, Cs, Rb, Sr, Br, Cr, Mo, Co, Ba, Cu, Zn, Cd, Pb, Mn, Se, As, V and Ni were determined in drinking water supplies (public taps, domestic taps and treated water from public water sources) and groundwater supplies (boreholes and shallow wells) in some parts of Southern Nigeria. The water samples were analysed using inductively coupled plasma mass-spectrometry (ICP-MS). The mean levels (microgram/l) of all the elements ranged between 0.35 microgram/l for Cs and 87.3 micrograms/l for Zn in the drinking waters and between 0.54 microgram/l for Co and 420.3 micrograms/l for Ba in the groundwaters. A comparison of the elemental concentrations with WHO guidelines showed that with the exception of violations of Cd, Cr and Se limits in some of the drinking water samples, the levels of all the other elements investigated were below the WHO maximum allowable concentrations.

Environmental impact of vehicular traffic in Nigeria: health aspects.

Blood lead levels were analysed and pulmonary function tests were performed on Nigerian traffic wardens, comprising sixty from Lagos (ages 24-52 years; 27 +/- 6), thirteen from the sparsely populated university town of Ile-Ife (ages 22-40 years; 27 +/- 8) and a control group of twenty-four subjects (age 19-55 years; 31 +/- 8). Perkin-Elmer Zeeman 3030/HGA 600 AAS was used for blood analysis. The mean lead level in Lagos wardens was 18.1 +/- 6.4 micrograms/dl, which was significantly higher than the level of 10.2 +/- 2.7 micrograms/dl in Ife wardens and 12.9 +/- 7.0 micrograms/dl obtained in the controls (P < 0.001). However, there was no significant difference between the levels of blood lead in Ife traffic wardens and normal controls. Significant differences (P < 0.0005) in spirometric measurements--peak flow rate (PEFR), forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC)--were observed between traffic wardens and control subjects. The noise levels measured along traffic roads exceeded the threshold for hearing damage.

Study of trace elements in blood of cancer patients by proton-induced X-ray emission (PIXE) analysis.

Proton-induced X-ray emission (PIXE) analysis was employed to determine the concentrations of six elements in the plasma and erythrocytes of 18 cancer subjects (15 males and 3 females) with neoplastic disorders and in 70 controls (35 males and 35 females). It was found that the concentrations of Br, K, and Zn were significantly elevated in the erythrocytes of the cancer subjects compared to the controls, whereas the concentration of Fe was significantly depressed, but with no difference observed in the concentration of Ca. In the plasma, the concentrations of Br, Cu, Ca, and K were significantly elevated, whereas the concentrations of Fe and Zn were found to be significantly depressed compared to the controls.

Elemental concentrations in nigerians with affective disorders using proton-induced X-ray emission.

The concentrations of a number of elements are determined in the plasma and erythrocytes of 21 Nigerians (11 females, 10 males) with symptomatic affective disorders (11 depressives, 10 manics) and in 40 normal controls using proton-induced X-ray emission (PIXE) analysis. The study shows that there is significant elevation of plasma K and Zn, as well as the erythrocyte S in the patients relative to the controls. The plasma and erythrocyte Cu, and the erythrocyte P, Ca, Fe, and Zn are significantly lower in the patients compared to the controls. However, the plasma levels of Ca, S, Fe, and Br are similar in both the patients and the controls. Similarly, the concentrations of K, Br, and Rb show no significant difference in the erythrocytes of patients and controls.

Elemental composition of head hair and fingernails of some Nigerian subjects.

In this article, we present the elemental concentrations determined by INAA for 30 elements measured in some or all head hair samples of 100 Nigerian subjects and 20 elements in the fingernails of some of the same subjects. Measurements of the skewness of the distribution of each element in both tissues confirm previous reports that many tend toward a log-normal distribution. Thus, their concentrations in the tissues may not be under any homeostatic control. The ranges of elemental concentrations together with the medians, and the arithmetic and geometric means, with their respective standard deviations are presented and compared with literature values for other populations. Correlations between elements detected in hair are also sought.

Correlations between trace element levels in head hair and blood components of Nigerian subjects.

Elemental concentrations in head hair and blood (whole-blood, erythrocytes and plasma) of 28 Nigerian subjects were determined using instrumental neutron activation analysis (INAA) and proton-induced X-ray emission (PIXE) techniques. Correlations found between different elements in hair and blood are reported. Hair levels of both zinc and chlorine were found to be significantly correlated with their levels in erythrocytes.

Baseline levels of elemental concentrations in whole blood, plasma, and erythrocytes of Nigerian subjects.

In this pioneering effort on Nigerians, the arithmetic means, ranges, and standard deviations for the concentrations of the 13 elements, Br, Ca, Cl, Cu, Fe, K, Na, P, Pb, Rb, S, Se, and Zn, detected in freeze-dried whole blood, erythrocytes, and plasma of 120 subjects drawn from different geographical regions of Nigeria are reported. Elemental analyses have been carried out largely using instrumental neuron activation analysis (INAA) with both proton-induced X-ray emission (PIXE) and graphite furnace atomic absorption spectrometry (AAS) serving as complementary techniques. Our values, compared with similar data from other parts of the world, show a general good agreement. Values in male and female subjects are compared. Correlations between different elements are also noted.

Non-CO2 gaseous emissions from upstream oil and gas operations in Nigeria.

The Nigerian crude oil is formed in association with natural gas. The associated gas has mostly been flared in the process of crude oil exploitation. Current estimates are that approximately 70% of produced natural gas is flared. Carbon monoxide, volatile organic compounds and nitrogen oxides emissions from oil and gas exploitation activities are presented for major combustion activities: gas flares and power generation at oil fields for oil and gas gathering systems. The emissions rates and combustion efficiency for a newly tested modified flaring system with enhanced air supply and liquid aspiration system for the atomization of the condensate phases of the flared gas was found to be capable of improving combustion efficiency by 20% or more in comparison with the conventional flare-type currently in vogue. Flare emissions for CO and NOx are an order of magnitude higher than other sources in the oil and gas sector.

Trace element distribution in the hair of some sickle cell anemia patients and controls.

Hair samples of some young sickle cell anemia (SCA) and control patients in Nigeria were analyzed for 12 elements, viz, Se, Hg, Cr, Fe, Zn, Co, Cu, Br, As, Sb, Na, and Sc, using Instrumental Neutron Activation Analysis (INAA). With the exception of Cu, which was found to be significantly higher in the hair of SCA patients (at the 0.05 level of the t-test), there were generally no significant differences in elemental concentrations within the two groups. A preliminary study of the elemental contents of the fingernails of the same subjects showed a higher abundance of most of the elements in nail than in hair. These preliminary results were compared with similar studies from some other parts of the world.