1. There has been an enormous increase in the production and use of synthetic chemicals and in exposure to pollutants this century, which has accelerated in the last 50 years. Five million different chemicals are now recognized and relatively few of the chemicals in use have been adequately tested for toxicity to man or the environment. Of the 3000 or so in large-scale use, the 'minimal' toxicity data required by the Organization for Economic Co-operation and Development (OECD) for a preliminary assessment of health hazards to humans are not publicly available for 75%. There has been little study of exposure to combinations of different chemicals, either simultaneously or in sequence. 2. Establishing the chronic effects of any exposure is very difficult, even in experimental animals. In humans who are regularly exposed to chemical cocktails that vary from day to day and year to year, it becomes almost impossible unless the outcome is a very rare and well-documented condition. However, it is equally impossible to establish that such exposures are without risk. 3. Long-term ill effects have been reported from chronic exposure to heavy metals and by a minority of individuals after the exposure of defined populations to synthetic or pollutant chemicals-chemical accidents, pesticide exposure, 'sick' buildings, implants, etc. Most of these individuals report that their late symptoms are exacerbated by ambient exposures to volatile organic chemicals (VOCs) emitted by everyday products (for instance, perfumes, washing powders and cigarette smoke), which were previously tolerated without trouble and indeed often enjoyed. Similar chronic conditions occurring in other individuals, after single toxic or sub-toxic exposures, or prolonged low-dose exposure, tend to be overlooked. This condition is referred to as multiple chemical sensitivity (MCS). 4. The genuine nature of MCS has been recognized by officially commissioned reports from independent scientists in the USA and the UK, who have concluded that it is a valid diagnosis and a sometimes disabling condition, although all have stressed the need for further research. 5. Because of their biological roles, it has been suggested that pesticides (designed to interfere with enzymes) and hormone mimics may have a particular place in inducing MCS. However, the evidence also implicates VOCs and other compounds such as diesel particulates and the nitrogen oxides. 6. A large study in Bristol has found associations of air freshener and aerosol use with increased prevalence of certain symptoms in both mothers and babies. 7. Patients with MCS are often treated as if their symptoms are psychologically caused. There is no good evidence for this. On the other hand, double-blind challenges have provided positive evidence for the provocation of symptoms by certain chemicals (varying in different patients) at levels too low to be recognized by the patient; challenge has been reported to cause changes in brain activity on SPECT scans. 8. These patients are usually found, on investigation, to be suffering also from the effects of hidden' allergy (intolerance) to a number of different foods and food additives. The symptom reactions they experience are often dissociated in time from the ingestion of the trigger food in such a way that the connection has not previously been made.

Editor—Beral et al have reported an increased relative risk of death from cervical cancer among women using oral contraception.1 Their study controlled for smoking but not for the other principal risk factors for cervical cancer, which include infection with human papillomavirus of a high risk type, sexual behaviour, and inadequate cervical screening. There is therefore a considerable risk of confounding, which could account for the results. The authors do not give patterns of use of contraception by never users and non-users of oral contraceptives; it would be interesting to know what proportion of this comparison group was using barrier methods. Such women are at reduced risk of cervical cancer,2 and therefore a comparison that includes a large proportion of women using barrier methods will seem, artificially, to increase any risk in pill users. It should also be noted that durations of use of less than 10 years are not associated with a significant increase in risk in this study. This apparent duration of use effect may well be related to the risk of acquiring an infection with an oncogenic human papillomavirus.

Attention-deficit/hyperactivity disorder (ADHD) is a behavioral disorder that typically begins in childhood and is characterized by a short attention span (inattention), an inability to be calm and stay still (hyperactivity), and poor impulse control (impulsivity). Some people with ADHD have problems with only inattention or with hyperactivity and impulsivity, but most have problems related to all three features.

(1996). Effective Nutritional Medicine: The Application of Nutrition to Major Health Problems: British Society for Allergy and Environmental Medicine with the British Society for Nutritional Medicine. Journal of Nutritional & Environmental Medicine: Vol. 6, No. 2, pp. 191-232.

Music is a crucial element of everyday life and plays a central role in all human cultures: it is omnipresent and is listened to and played by persons of all ages, races, and ethnic backgrounds. But music is not simply entertainment: scientific research has shown that it can influence physiological processes that enhance physical and mental wellbeing. Consequently, it can have critical adaptive functions. Studies on patients diagnosed with mental disorders have shown a visible improvement in their mental health after interventions using music as primary tool. Other studies have demonstrated the benefits of music, including improved heart rate, motor skills, brain stimulation, and immune system enhancement. Mental and physical illnesses can be costly in terms of medications and psychological care, and music can offer a less expansive addition to an individual's treatment regimen. Interventions using music offers music-based activities in both a therapeutic environment (Music therapy) with the support of a trained professional, and non-therapeutic setting, providing an atmosphere that is positive, supportive, and proactive while learning non-invasive techniques to treat symptoms associated with various disorders – and possibly modulate the immune system.

A cohort of 19 consecutive asthma patients, stable prior to admission, were investigated in the ‘clean’ atmosphere of the Airedale Allergy Centre, starting with a therapeutic fast. the peak expiratory flow rate (PEF) fell initially, whether medication had been reduced or not (withdrawal), but by about the sixth day most patients were symptom-fiee on less medication; by the last week of admission the reduction in medication was very highly significant (p < 0.0005). All patients gave positive wheals on intradermal injection of inhalant allergens (4 prick-test negative). Bronchoconstriction was provoked by open food challenge in 18 patients, and by sublingual challenge with chemicals in ten patients.The implications of the findings were discussed with the patients at each stage of the investigation. They were discharged on ‘vaccines’ containing their Miller endpoints [1] for prophylaxis, and an individually designed rotation diet (including most trigger foods), and advised how to reduce exposure to relevant inhalants and chemicals.At follow-up >6 months after discharge, patients had more control over their asthma: 13/19 (68%) claimed to be at least ‘definitely better': 5 ‘well’ or ‘almost well'. Symptoms were significantly reduced, and medication was lower at follow-up than on admission (p < 0–01). Compliance correlated with outcome (tau=0–37, p < 0.05): outcome was not related to inhalant prick-test reactivity. the study underlines the need for a randomized trial testing this management against conventional management of asthma.

The standard 3-week inpatient regime in the Airedale Allergy Centre for investigation of chronic symptoms involves a 5-day fast, followed by three single-food challenge meals a day. Endpoint titration [1] is used to curtail adverse reactions, and to test inhalants and chemicals.In 19 consecutive asthmatics, the peak expiratory flow rate (PEF) was consistent after some of the 646 food challenges, but fell after others, and was usually restored bv endpoint titration using dilutions of an extract of the trigger food. Bronchoconstriction was provoked and relieved by different dilutions of some of the chemicals and chemical mixtures tested sublingually. Results are demonstrated on continuous PEF charts, each covering nine or more challenges over several days: individuals differed in the profile of foods and chemicals provoking bronchoconstriction.The overall distribution of the maximum change in the PEF after each food challenge in nine patients on no asthma medication in the ‘clean’ conditions differed from the expected best-fit normal distribution (p < -0001); changes of more than 20 l/min were unlikely to have occurred by chance. the PEF fell after all types of food, but there were differences (p < 0.05), with more frequent drops (often delayed) after meat, fish and grains. When the PEF remained low after repeated adverse reactions, recovery most frequently occurred after a fruit meal (p < 0.0001). Genuine increases in the PEF were also noted.

Peripheral-blood basophils were counted, in thick smears, in samples from patients with primary bronchial carcinoma, from patients in the same wards and from normal individuals. The median counts for patients with other chest conditions (15.5/microliter) and bronchial-carcinoma patients free of tumour months to years after resection (16/microliter) did not differ from those for normal individuals (19/microliter), but tumour-bearers showed higher counts (median 33/microliter), 24/41 having counts above the highest count in normal individuals (29/microliter): P less than 0.002). The highest values were in patients with squamous bronchial carcinoma, apparently reflecting spontaneous challenge of an anti-tumour immune response. In those tested at the time of diagnosis, higher values in both lymphocyte and basophil counts were related to surgical resectability.

Plasma and buffy-coat vitamin C were estimated in 158 samples from 139 lung-cancer patients, at all stages of the disease. Most samples showed hypovitaminosis C in both estimations: 64% had plasma, and 25% buffy-coat values below the thresholds for incipient clinical scurvy (0.3 mg% and 10 micrograms/10(8) cells respectively). Levels were diet-dependent and could be increased by oral supplements. Levels were low both in tumour-bearing patients and in those clinically free of disease after resection. The latter had particularly low values during the first 6 months, indicating the utilization of vitamin C in surgical repair. The vitamin C content of 13 primary lung tumours was assayed: tumours had a higher vitamin C content (mean 111.6 +/- 55.1 micrograms/g tissue) than normal lung (58.5 +/- 20.4 micrograms/g). Mononuclear cells from normal individuals show a higher vitamin C content than polymorphs, but in lung-cancer patients the expected correlation of buffy-coat vitamin C with the proportion of lymphocytes in peripheral blood was obscured by an inverse correlation in patients with relative lymphocytosis (greater than or equal to 25% lymphocytes), confirmed by an inverse correlation of the proportion of lymphocytes in peripheral blood with mononuclear-cell vitamin C in 14 patients in whom this was measured. These correlations were unaffected by controlling for plasma values, and indicate the utilization of vitamin C in lymphocyte-related anti-tumour mechanisms. Vitamin C is necessary for phagocytosis and for the expression of cell-mediated immunity. In view of the increasing circumstantial evidence that immune mechanisms exert some measure of control on tumour extension and metastasis in man, the effect of supplementation with vitamin C in lung-cancer patients on survival should be tested in a clinical trial.

A retrospective study of the history of drug use in cancer patients, conducted in general practice and involving 972 patients, has suggested that concurrent treatment with barbiturates and benzodiazepines may involve a cancer risk. Concurrent usage of other drugs with barbiturates was investigated because barbiturates have been reported to alter the handling of other drugs by liver microsomes and to interact with chemical carcinogens in experimental animal systems. If the risk has a basis in fact, it may lie behind the recent report of a small cancer risk associated with barbiturate treatment, in a prospective study based on computerized prescription information in a defined population, raising the hope that our finding can be tested in a larger study. A possible risk associated with prolonged treatment with cortisone related drugs could not be excluded. Four per cent of the cancer patients had tumours at sites consistent with reported occupational hazards and a further 4% suspected site-hazard associations. Occupation and smoking did not contribute to the drug associations noted. Entry of cancer patients from general practice gave a true sample of cancer patients in the area, judged by the distributions of age, sex, marital status and cancer site. Choice of controls from consultations for a new complaint resulted in a group showing deviation in the types of patient similar to those reported for consultations in general practice.