Health response of two communities to military antennae in Cyprus.

OBJECTIVES: This study investigated concerns that have been raised about past and future health effects caused by high power transmissions of high frequency (7-30 MHz) radio waves from military antenna systems at Akrotiri, Cyprus. METHODS: A cross-sectional study of three villages (two exposed, one unexposed) collected longitudinal and short-term radiofrequency measurements. Health data were collected using questionnaires containing information on demographic factors, specific illnesses, general health (SF-36 well-being questionnaire), reproductive history, childhood illnesses, risk perception and mortality. Analysis was with SPSS v11.5 using cross tabulations of non-parametric data and tests for significance. Key health outcomes were subjected to logistic regression analysis. RESULTS: Field strengths within the two "exposed" villages were a maximum of 0.30 (Volts/Vm(-1) metre) from the 17.6 MHz military transmissions and up to 1.4 Vm(-1) from unspecified sources, mainly cell phone frequencies. The corresponding readings in the control village were <0.01 Vm(-1). Compared with the control village there were highly significant differences in the reporting of migraine (OR 2.7, p<0.001), headache (OR 3.7, p<0.001), and dizziness (OR 2.7, p<0.001). Residents of the exposed villages showed greater negative views of their health in all eight domains of the SF-36. There were also higher levels of perceived risk, particularly to noise and electromagnetic "pollution". All three villages reported higher values of risk perception than a UK population. There was no evidence of birth abnormalities or differences in gynaecological or obstetric history. Numbers of cancers were too small to show differences. CONCLUSION: It was clear that even this close (1-3 km) to powerful transmissions, the dominant sources of radiofrequency fields were cell phone and national broadcast systems. There was no excess of cancer, birth defects or obstetric problems. There was heightened risk perception and a considerable excess of migraine, headache and dizziness, which appears to share a gradient with radiofrequency exposure. The authors report this association but suggest this is unlikely to be an effect of radiofrequency and more likely to be antenna visibility or aircraft noise.

Gamma-radiation-induced apoptosis in human colorectal adenoma and carcinoma cell lines can occur in the absence of wild type p53.

The tumour suppressor gene p53 codes for a transcription factor which is thought to play a critical role in the induction of G1 cell cycle arrest and programmed cell death (apoptosis) following DNA damage by ionizing radiation. The aim of this investigation was to determine whether a p53 independent radiation-induced apoptosis pathway exists in human colon epithelial cell lines. This report describes the induction, by gamma-radiation, of apoptosis in the colorectal adenoma cell line S/RG/C2, and in the colorectal carcinoma cell line PC/JW, both of which lack wild type p53. In addition, flow cytometry revealed that both cell lines failed to arrest in G1 after radiation. Thus, although loss of wild type p53 may abrogate G1 arrest, radiation-induced apoptosis can still occur in human colonic tumour cell lines through a p53 independent mechanism.

Identification in 2 independent samples of a novel schizophrenia risk haplotype of the dystrobrevin binding protein gene (DTNBP1).

CONTEXT: Recent research suggests that variation in the gene encoding dystrobrevin binding protein (DTNBP1) confers susceptibility to schizophrenia. Thus far, no specific risk haplotype has been identified in more than 1 study. OBJECTIVES: To confirm DTNBP1 as a schizophrenia susceptibility gene, to identify and replicate specific risk and protective haplotypes, and to explore relationships between DTNBP1 and the phenotype. DESIGN: Genetic association study based on mutation detection and case-control analysis. SETTING: All subjects were unrelated and ascertained from general (secondary care) psychiatric inpatient and outpatient services. PARTICIPANTS: The Cardiff, Wales, sample included 708 white subjects from the United Kingdom and Ireland (221 females) who met DSM-IV criteria for schizophrenia and were individually matched for age, sex, and ethnicity to 711 blood donor controls (233 females). Mean +/- SD age at first psychiatric contact for cases was 23.6 +/- 7.7 years; mean age at ascertainment was 41.8 +/- 13.5 years. The Dublin, Ireland, sample included 219 white subjects from the Republic of Ireland who met DSM-III-R criteria for schizophrenia or schizoaffective disorder and 231 controls. The mean age of the Irish cases was 46.0 +/- 8.5 years; mean age at first psychiatric contact was 25.2 +/- 12.4 years. MAIN OUTCOME MEASURE: Evidence for association between the DTNBP1 locus and schizophrenia. RESULTS: In the Cardiff sample, there was no evidence for association with previously implicated haplotypes but strong evidence for association with multiple novel haplotypes. Maximum evidence was found for a novel 3-marker haplotype (global P<.001), composed of 1 risk haplotype (P =.01) and 2 protective haplotypes, 1 common (P =.006) and 1 rare (P<.001). Specific risk and protective haplotypes were replicated in the Dublin sample (P =.02,.047, and.006, respectively). The only phenotypic variable associated with any haplotype was between the common protective haplotype and higher educational achievement (P =.02, corrected for multiple tests). CONCLUSIONS: DTNBP1 is a susceptibility gene for schizophrenia. Specific risk and protective haplotypes were identified and replicated. Association with educational achievement may suggest protection mediated by IQ, although this needs to be confirmed in an independent data set.

Pig alpha1, 3galactosyltransferase: a major target for genetic manipulation in xenotransplantation.

Terminal carbohydrate residues of glycolipids and glycoproteins display polymorphism among as well as within various species. With the exception of Old World monkeys, great apes and man, the Gala1,3Gal structure is widely expressed in all mammals examined so far. The lack of expression of the glycosyltransferase responsible for the synthesis of Gala1,3Gal leads to the production of high titers of natural antibodies (NAb) against the Gala1,3Gal of other species. The inactivation of this gene occurred during early evolution of primates. Neutralization of viruses (e.g. retroviruses) carrying the epitope, by the pre-formed human NAb, indicates one possible evolutionary reason for the polymorphism of terminal carbohydrates among as well as within species. It has been shown that this epitope constitutes the major target, on pig endothelial cells (EC), for the pre-formed human NAb resulting in a hyperacute rejection (HAR) response. This currently makes transplantation of e.g. pig organs to humans impossible. Efforts are currently underway to prevent or to eradicate the expression of this epitope in transgenic pigs. Such pigs are likely to display a greatly increased resistance to the HAR.

Factors involved in the cytotoxicity of UICC amosite towards macrophages.

The cytotoxicity of various ball-milled UICC amosite samples toward mouse peritoneal macrophages in vitro was examined. On increased ball milling, the cytotoxicity of the amosite samples fell. This decreased biological activity seemed to correlate best with number of fibers longer than 4 micron/micrograms dust, rather than total number of fibers or the electrophoretic mobility of the amosite samples.

Unpredictable serum levels after oral methotrexate in children with acute lymphoblastic leukaemia.

Serum methotrexate levels were measured for 5 h after oral intake in 11 children with acute lymphoblastic leukaemia. The curves obtained with the child's regular dose of methotrexate varied widely, and were independent of the doses used. Peak levels were found in samples taken up to 3h after ingestion, and ranged from 300 to 1250 ng/ml. In the doses used, methotrexate toxicity was present in one of the eleven children, and was associated with a delayed peak and a high 5-h methotrexate level. Individual drug metabolism could be an important factor in the response to treatment, and needs to be evaluated in the assessment of protocols.

In vitro demonstration of a fundamental difference in the proliferation of murine and human bone marrow and lymphocytes following ultraviolet irradiation: relevance to bone marrow transplantation.

Exposure of rodent allogeneic donor marrow and splenocyte grafts to ultraviolet radiation (UVR) has been shown to permit durable engraftment at doses that abolish graft-versus-host disease (GVHD) and graft rejection. We have compared both murine and human alloreactive and mitogen-induced lymphoid responses and bone marrow proliferation in mixed lymphocyte culture (MLC), phytohemagglutinin (PHA)-induced proliferation and colony-forming unit-granulocyte/macrophage (CFU-GM) assays using germicidal UVC (200-290 nm), broadband and narrowband UVB (290-320 nm) and UVA (320-400 nm) sources. Our data show a wavelength and dose-dependent reduction in lymphoid proliferation in the mouse with CFU-GM survival of 50-75% of control at doses required to abolish allogeneic lymphocyte responses for all lamps. In contrast, human lymphocyte responses are more resistant to UVC with CFU-GM proliferation reduced to zero when allostimulation is abolished. Mitogen-induced lymphoid responses show a similar wavelength-dependent sensitivity. Abolition of response in MLC using UV-irradiated stimulator cells was less sensitive than proliferation with UV-irradiated responder cells at all wavelengths in both species. With all sources, murine CFU-GM proliferation is less susceptible to UVR than human marrow at doses required to abolish lymphoid responses.

The effect of a 50 Hz magnetic field on cognitive function in humans.

OBJECTIVES: To examine whether the power frequency magnetic field of 0.6mT applied to humans has an effect on cognitive function as has been suggested by animal studies. These fields are less than the suggested intervention level in the UK of 1.6mT and are similar to those found close to some domestic appliances. METHOD AND MATERIALS: A randomized three-way cross-over design using a battery of computerized cognitive function tests were used in the presence or absence of a 50Hz or static magnetic field. Sixteen healthy volunteers undertook two training and three test sessions with a 50Hz or static 0.6 mT magnetic field from a set of coils centred on the head. RESULTS: In response to the 50 Hz field, disruptions of accuracy were seen from an attentional task (the ability to correctly recognize words shown 20min previously and the ability to maintain a string of digits in working memory). There was no similar response to comparable levels of static magnetic field. CONCLUSIONS: These tests indicated at least temporary deterioration in attention, and working and secondary memory performance while a 50 Hz field is applied. There were no adverse effects on speed from any of the tasks. It was not possible in this study to be sure if these effects were persistent.

Effect of a 915-MHz simulated mobile phone signal on cognitive function in man.

PURPOSE: To examine whether a simulated mobile telephone transmission at 915 MHz has an effect on cognitive function in man. MATERIALS AND METHODS: Thirty-six subjects in two groups were each given two training sessions and then three test sessions in a randomized three-way cross-over design. About 1 W mean power at 915 MHz from a quarter-wave antenna mounted on a physical copy of an analogue phone, as a sine wave, or modulated at 217 Hz with 12.5% duty cycle, or no power, was applied to the left squamous temple region of the subjects while they undertook a series of cognitive function tests lasting approximately 25-30 min. The second group was investigated for sleep, consumption of alcohol and beverages, and any other substances that might affect performance. RESULTS: In both groups, the only test affected was the choice reaction time and this showed as an increase in speed (a decrease in reaction time). There were no changes in word, number or picture recall, or in spatial memory. While an effect of visit-order was evident suggesting a learning effect of repeat tests, the design of the study allowed for this. Additionally, there was no systematic error introduced as a result of consumption of substances or sleep time. CONCLUSIONS: There was evidence of an increase in responsiveness, strongly in the analogue and less in the digital simulation, in choice reaction time. This could be associated with an effect on the angular gyrus that acts as an interface between the visual and speech centres and which lies directly under and on the same side as the antenna. Such an effect could be consistent with mild localized heating, or possibly a non-thermal response, which is nevertheless power-dependent.

Enhanced deposition of radon daughter nuclei in the vicinity of power frequency electromagnetic fields.

We report the attraction of radon daughter nuclei in normal domestic room air to everyday sources of power frequency electromagnetic fields. TASTRAK plastic track detectors were used to measure alpha-emission from the radon (222Rn) daughters 218Po and 214Po close to 50-Hz mains frequency power cables and domestic appliance leads. We observed that wires carrying mains frequency potential attract radon daughter nuclei in a manner visually similar to the attraction of iron filings to a magnet. Increased deposition of up to a factor of 18 was observed. Further experiments designed to simulate the effect of overhead power lines at ground level showed large scale variations in local plateout and airborne concentration of radon daughters. The effects appear to be due to interactions of the electric component of the EM-field with both the ultrafine and attached fraction of radon daughter aerosols. Three mechanisms have been examined. First, aerosols instantaneously polarize in sympathy with the electric component of an applied mains frequency EM-field and as a result may migrate up strong E-field gradients. This effect is however quite weak and may only affect larger aerosols in strong field gradients. Second, charged aerosols oscillate in a 50-Hz field and in the case of the ultrafine fraction this may lead to significantly increased plateout. Third, there is the possibility that oscillation of charged aerosols induces fluctuations in the magnitude of the instantaneous charges carried and this results in a diffusive-like motion along the field lines. The effect on dose to body organs is considered. Enhanced plateout on the skin is likely, increasing the dose to the basal layer. The dose to internal organs is governed initially by inhalation and lung deposition of radon daughters. Therefore increased local concentration in room air could lead to increased dose by inhalation. E-fields are heavily attenuated by the human body and body values in tissue of no more than 10(-4) of the external field strength have been suggested. Nevertheless calculations suggest that under exposure to strong external fields this may still be sufficient to alter the deposition pattern of the charged component of the ultrafine fraction in the bronchial region. In contrast it is unlikely that internal electric fields could significantly affect the attached radon daughters. In this context the lack of measurements of residual E-fields in the cavities of the mouth, pharyngeal and bronchial regions is of considerable importance and should be addressed. We believe that the observations may have implications for the apparent enigma that there is no persuasive biological evidence to show that power frequency electromagnetic fields can influence any of the accepted stages in carcinogenesis. On the contrary, the observations show that EM-fields can concentrate in their vicinity a cocktail of radon daughter nuclei, a known carcinogen, and presumably other potentially harmful agents.

A laser Doppler cytopherometer for measurement of electrophoretic mobility of bioparticles.

A wide-angle laser Doppler spectrometer has been combined with a number of high-field-strength cytopherometer designs for the purpose of studying the electrophoretic mobility (EPM) of biological particle and cells in non-physiological and physiological media. This produces a typical Doppler shift of 100 Hz for an EPM of 1.0 micrometers s-1 V-1 cm, and a shift-to-width ratio of greater than 10 for human erythrocytes in physiological saline. The unit uses two equal-intensity beams of identical pathlength, crossing in the measuring volume at an angle of 40--90 degrees in air and can function in either a fringe or coherent mode. The resolution for human cells and bioparticles is comparable with conventional cytopherometry but the data collection rate is many times higher.

Theoretical and experimental comparison of three types of electromagnetic hyperthermia applicator.

There is evidence that heating of malignant tissue in the treatment of cancer may be beneficial and so the performance of different applicator designs needs to be established. A theoretical model of the dielectric loaded waveguide applicator is compared with models of two other applicators which depend on energy radiated from conductors carrying high frequency current. The latter are exemplified by the compact resonant patch applicator and the lightweight inductive current sheet applicator. It is shown that heating profiles and field penetration of each applicator are similar for equal radiating areas, and these results have been substantiated experimentally. Impedance match as a function of frequency and load is also compared for the three types of applicator.

Approximate distribution of dose among foetal organs for radioiodine uptake via placenta transfer.

Absorbed radiation doses to internal foetal organs were calculated according to the medical internal radiation dose (MIRD) technique in this study. Anthropomorphic phantoms of the pregnant female as in MIRDOSE3 enabled estimation of absorbed dose to the whole foetus at two stages of gestation. Some foetal organ self-doses could have been estimated by invoking simple spherical models for thyroid, liver, etc, but we investigated the use of the MIRDOSE3 new-born phantom as a surrogate for the stage 3 foetus, scaled to be compatible with total foetal body mean absorbed dose/cumulated activity. We illustrate the method for obtaining approximate dose distribution in the foetus near term following intake of 1 MBq of 123I, 124I, 125I or 131I as sodium iodide by the mother using in vivo biodistribution data examples from a good model of placenta transfer. Doses to the foetal thyroid of up to 1.85 Gy MBq(-1) were predicted from the 131I uptake data. Activity in the foetal thyroid was the largest contributor to absorbed dose in the foetal body, brain, heart and thymus. Average total doses to the whole foetus ranged from 0.16 to 1.2 mGy MBq(-1) for stages 1 and 3 of pregnancy using the MIRDOSE3 program, and were considerably higher than those predicted from the maternal contributions alone. Doses to the foetal thymus and stomach were similar, around 2-3 mGy MBq(-1). Some foetal organ doses from the radioiodides were ten times higher than to the corresponding organs of the mother, and up to 100 times higher to the thyroid. The fraction of activity uptakes in foetal organs were distributed similarly to the maternal ones.

Power frequency electromagnetic fields and health. Where's the evidence?

Twenty years ago concerns were raised that exposure to power frequency (or extremely low frequency (ELF)) electromagnetic fields (EMFs) may be associated with an increased risk of cancer or other health hazards. Subsequently no associations have been shown between laboratory magnetic field exposures and carcinogenesis in either animal or cellular models. Indeed, studies have demonstrated that magnetic fields are not associated with cancer. However, the puzzle remains that the results of some epidemiological studies may be interpreted as suggesting that living close to high-voltage transmission (HVT) lines appears to increase slightly the risk of childhood leukaemia. Alternatively, these results could result from small biases and errors in individual studies, which might not necessarily be the same in each study. The nature of the epidemiological studies (power-line, wire code, magnetic field or appliance based) appears to determine whether and how the EMFs associated with HVT lines might be a risk factor. It is possible that a simple association with either magnetic or electric field exposure may not be the whole answer, and an alternative mechanism is always a possibility. Although the interpretation of the available evidence by most expert bodies has led them to conclude that exposure to power frequency electric and magnetic fields is not a human health hazard, a working group under the auspices of the US National Institute of Environmental Health Sciences (NIEHS) concluded that there was a possible low risk associated with certain exposures to ELF magnetic fields. NIEHS itself interpreted the finding as insufficient to warrant aggressive regulatory concern but stated that, because virtually everyone is routinely exposed to ELF EMFs, passive regulatory action is warranted, such as a continued emphasis on educating both the public and the regulated community on means aimed at reducing exposures. These analyses, conclusions and advice are not contradicted by subsequent studies, and therefore the conclusion of the World Health Organisation that further research is needed seems valid.

Magnetic fields from domestic appliances in the UK.

In a survey of 50 UK homes the 50 Hz fundamental and harmonic magnetic fields generated by 806 domestic appliances found in the homes, and used regularly by mothers, were measured. Measurements were made in the direction of most likely access, and from the surface of the appliances. Mothers completed a questionnaire on the use of appliances and were monitored for 24 h so that acquired exposure could be compared with the measured ambient fields in the home. Appliances were measured at standard distances and an algorithm was used to calculate fields at 100 and 50 cm to remove room background contributions. A few appliances generated fields in excess of 0.2 microT at 1 m: microwave cookers 0.37 +/- 0.14 microT; washing machines 0.27 +/- 0.14 microT; dishwashers 0.23 +/- 0.13 microT; some electric showers 0.11 +/- 0.25 microT and can openers 0.20 +/- 0.21 microT. Of continuously operating devices, only central heating pumps (0.51 +/- 0.47 microT), central heating boilers (0.27 +/- 0.26 microT) and fish-tank air pumps (0.32 +/- 0.09 microT) produced significant fields at 0.5 m. There were no obvious ways to group different types of appliances as high- or low-strength sources. Mothers spent on average about 4.5 h per day in the kitchen, where the strongest sources of magnetic field were located.

Domestic magnetic field exposures in Avon.

To define a protocol for surrogate measurement of magnetic field exposure by questionnaire, a series of spot and 24-hour measurements was made at 50 houses in Avon, UK. Measurements were made with Emdex II equipment in the centres of rooms with the house power encountered at the start of the visit, and then with all power to the house isolated at the main switch. The mean spot magnetic field averaged over the 50 homes for each room varied between 0.011 and 0.023 microT with an overall mean (0.017 +/- 0.003) microT with the power 'on', and between 0.008 and 0.015 microT, giving an overall mean (0.012 +/- 0.002) microT with power 'off'. Measurements over 24 h in the three main occupancy rooms showed a distinct diurnal variation in the overall mean magnetic field of the 50 homes by a factor of three, giving a 24-hour mean of (0.044 +/- 0.06) microT; at the same time mean recorded personal exposure for the occupants monitored was (0.067 +/- 0.08) microT. These values appear low compared with, for example, USA domestic levels of magnetic field exposure demonstrated in several studies, but also show a wide variation in individual values, which could not be predicted from spot measurements.

The analysis of the red cell unsaturated fatty acid test for multiple sclerosis using laser cytopherometry.

Using a laser cytopherometer, the electrophoretic mobility of glutaraldehyde-fixed erythrocytes from patients with multiple sclerosis (MS) has been compared with that of cells from control subjects. The effect of incubating cells with different concentrations of linoleic acid (LA) has been tested. At a concentration of 20 micrograms LA per 2 x 10(7) cells, slower mobilities were observed, on average, than those of control subjects, but there was overlap between control and patient groups. At a higher concentration of LA (160 micrograms per 2 x 10(7) cells), many of the MS samples showed a slower mobility than the control samples, although overlap was still evident. The value of the application of laser cytopherometry compared with conventional cytopherometry to this type of test is discussed.

RF field penetration from electrically small hyperthermia applicators.

The penetration of RF energy into lossy material from an electrically small radiating aperture is theoretically almost independent of frequency and this is confirmed by measurement.

Home radon levels and seasonal correction factors for the Isle of Man.

Ionizing radiation dose levels due to home radon can rise to levels that would be illegal for workers in the nuclear industry. It is well known that radon levels within homes and from home to home, and also from month to month, vary considerably. To define an Isle of Man radon seasonal correction factor, readings were taken in eight homes over a 12 month period. An average island indoor exposure of 48 Bq m(-3) (range 4-518 Bq m(-3)) was determined from 285 homes selected from a cohort of 1300 families participating in the European Longitudinal Study of Pregnancy and Childhood (ELSPAC) in the Isle of Man. This compares with a UK home average of 20 Bq m(-3) and a European Union average (excluding UK) of 68 Bq m(-3). Ten homes of those measured were found to have radon levels above the National Radiological Protection Board 200 Bq m(-3) action level. There are 29,377 homes on the Isle of Man, suggesting that there could be some 900 or more homes above the action level. No statistical difference was found between the NRPB and Isle of Man seasonal correction factors.

A comparison of four ultraviolet sources to alter graft-versus-host responses.

Graft-versus-host disease (GVHD) is a major contributor to the morbidity and mortality associated with allogeneic bone marrow transplantation. Direct ultraviolet B (UVB) irradiation of bone marrow and spleen cell allografts in mice using broadband lamps is known to abolish alloreactive responses which would normally cause GVHD. Using a histoincompatible murine model, we have extended these observations by comparing the physical spectrum of four UV sources (the Philips TUV8W, TL12 and TL01, and the Spectronics XX15B) with in vitro assessment of bone marrow progenitor cell damage and suppression of lymphocyte proliferation and in vivo comparison of the effect on GVHD of the TL12 and XX15B and on the rate of engraftment with the TL12. At doses of uv found to abolish lymphocyte proliferation (2.5, 7, 12 and 1000 J m(-2) with the TUV8W, XX15B, TL12 and TL01 lamps) colony-forming unit granulocyte-macrophage (CFU-GM) proliferation was reduced to 81%, 71%, 79% and 62%, respectively. At an optimal dose found to suppress GVHD (100 J m(-2) integrated radiant energy from 200-320 nm for the TL12 and XX15B) CFU-GM proliferation showed a reduction of 98% with the XX15B and 86% with the TL12. At this radiant energy with the TL12, the rate of bone marrow engraftment was impaired with 72% marrow cellularity at 2 weeks, decreasing to 48% after 200 J m(-2). Our results with this model demonstrate that broadband UVB irradiation of bone marrow permits transplantation across a major histocompatibility barrier. Furthermore we have provided in vitro evidence that narrowband UVB or UVC might potentially be applied to this model.