Population health looking upstream

Lead

on

the range

SIR-Ozanoff (Jan 1, p 6) points out the risks of lead poisoning associated with shooting ranges and that this is one of the largest unregulated sources of occupational lead exposure for adults. Pistols emit various particles, including lead, from all their orifices when they are fired. About 50% of the lead is in respirable particles, and particles of other toxic elements, such as antimony, copper, arsenic, and barium, have also been detected.’1 The risks of lead poisoning are not only a function of the type of weapon used and the number of rounds fired, but also depend on ventilation and type of shooting range. Dust accumulates in shooting ranges, and in older ones with woodwork this can be in substantial amounts. More modern ones have smooth washable surfaces and so pose less risk. The risks of a particular shooting range can be monitored by measuring air lead and by swabbing surfaces for dust levels. Not only instructors and regular users of shooting ranges but also the people who clean them are at risk.2 Member-run shooting clubs are an increasingly popular leisure activity in the UK; there are more than twenty such clubs in the Greater Manchester area alone. Commercial premises with employees are monitored and advised by the Health and Safety Executive, but member-run clubs are monitored by already overstretched local authorities as part of their control of leisure activities. These clubs may not be wholly aware of the need for safety measures; there are reports of clubs in various parts of the country that are rarely cleaned, poorly ventilated, and even used for other leisure activities, despite the fact that some members are heavy users of the facilities. At one local club some members shoot between 2000 and 3000 rounds a week. A check on members in one Greater Manchester shooting range showed that 3 of 4 members who "did a great deal of shooting" had blood lead concentrations that would have required 6 monthly monitoring if they had been working in industry.33 No guidelines exist for clubs about reduction of the risk of lead inhalation. I have contacted the National Pistol Association and other shooting organisations to raise this issue, and to suggest that guidelines should be drawn up. In the meantime, individual shooters should follow commonsense guidelines: do your shooting and leave immediately, and never eat, drink, or smoke on a firing range. Those who do a great deal of shooting should have a regular medical check-up, including measurement of blood lead where indicated. Paula McDonald Department of Public Health Medicine, West Pennine Health Purchasing Consortium, Hyde, Cheshire SK14 1DB, UK 1

2 3

Olmez I, Kotra JP. Airborne lead and trace elements in an indoor shooting range: a study of the DC national guard armory pistol range. Environ Toxicolo Chem 1985; 14: no 4. Anonymous. On site consultation: firing range lead exposure. Hazard Subst Adv 1988; 9: no 12. Manchester Area Pollution Advisory Council. Monitoring Report, 1990.

Population health looking upstream SiR-The title of your Feb 19 editorial (p 429) has particular appeal to a retired consultant paediatrician. The notion of child health came in just after the World War II on the back of therapeutic paediatrics, with the possibility of infantile diseases and deaths diminishing and positive health taking over. The monitor was to continue to be the postneonatal mortality rate because of its acceptance world wide as the best single indicator of the social development of any

community. 856

Since the UK welfare state began the postneonatal rate has continued to fall with a plateau between 1978 and 1988 (about 4-1-4-3 per 1000 livebirths). This plateau is blamed on social deprivation and poverty.’ Since that time, however, the rate has been halved to 2-2 per 1000 in only 4 years :2 of this, 08 is attributable to the combined cot-death rate (cot plus respiratory) which has social connections, and 0-5 to congenital anomalies which have not. A third of the remaining 09 is attributable to perinatal causes and 0.2 to the meningitides. The remaining 0-4 is divided among many causes, each with small numbers. The rate is more liable to fall further than to rise since for 100 years it has never really done so. This figure of 2-2 per 1000 is also the rate enjoyed by Sweden3over the past 20 years and often cited as a goal for the UK. If all socially-related baby deaths disappear how would our thinking about social deprivation be affected? Barker4 has proposed that much adult disease may have resulted from previous disease in infancy, but Chandlers believes that social deprivation is not as important as in the past. I think that the social deprivation that led to high post-neonatal mortality will soon have gone forever. We shall then be left with only the kind of social deprivation that leads to high adult mortality rates. In adults mortality from coronary occlusion is falling both here and in the USA, but some believe that it is an epidemic. If coronary occlusion, too, disappears and everyone wonders why, I have an unsupported suggestion. During the World War II national dried milk was introduced which saved many infant lives, but later, when given in concentrated form, it proved capable of causing hypertonic dehydration, a feature of which is systemic hypertension. Thus national dried milk could have been the cause of a socially-related epidemic since mothers in social classes IV and V might be more likely to give extra milk powder on the basis that what is good will be even better in larger quantities. So the cause of the epidemic was two-fold-the provision of milk free by the State and the giving of too much by the parent. The similarity to cot death is obvious: the cost/benefit index of changing from prone to supine sleeping and not overheating is enormous, and even more so if heartache were measurable. R R Gordon Apartment 12, Gosfield Hall, Halstead, Essex C09 1SF, UK 1

2

3 4 5

Office of Population Censuses and Surveys. Infant and Perinatal Mortality: RHA’s and DHA’s, 1988-92. London: HM Stationery Office, 1988-92. Black D. Deprivation and health. BMJ 1993; 307: 1630-31. Leon DA, Vagero D, Otterblad Olaussen P. Social class differences in infant mortality. BMJ 1992; 305: 687-91. Barker DJP, Osmond C. Childhood respiratory infection and adult chronic bronchitis in England and Wales. BMJ 1986; 293: 1271-75. Chandler BG. Public health versus personal health. Public Health 1993; 107: 397-99.

SiR-Your discussion of the need for multidisciplinary research in epidemiology and public health is timely. Recognition of the complementary relation between quantitative and qualitative research is essential if social and behavioural scientists are to be full intellectual contributors to population health research and programmes. Nowhere is this more true than in AIDS. The US Centers for Disease Control and Prevention sponsored research on the prevalence and risk of HIV infection in California’s Vietnamese community, the largest in the USA. Earlier work and thinking about this ethnicity suggested that because of a tradition of sexual conservatism and strong social taboos and stigmatisation for homosexuality, the prevalence and risk for HIV infection were much less than those for the US population in general. Three distinct but interactive research components were implemented: a seroprevalence study

targeted at Vietnamese with potentially increased risk for HIV; study of ethnics by structured interview, case studies, focus groups, and participant observation to describe the spectrum and expression of individual sexual behaviours; and a community survey of HIV/AIDS knowledge, attitudes, and self-reported sexual and other high-risk behaviours to quantify the prevalence of these within the population (refs 1 and 2, and unpublished). The data derived from the components were intended to be mutually informative. Thus, for example, whereas the seroprevalence study found an unexpected (and closely similar to the USA) rate of infection in selected parts of the community, especially in homosexuals, the ethnicity studies could identify the existence of a distinct self-identified homosexual Vietnamese community with an intergenerational support system. Furthermore, the community survey could quantify the percentage of Vietnamese men in this community who visited prostitutes in California and across the border in Mexico, whereas ethnicity studies provided insight into the sociocultural setting of such behaviour and documented the existence of a well-established transportation system to bars frequented almost exclusively by Vietnamese men for this purpose. The use of quantitative and qualitative methods also allowed for validity checks in the research. For example, no homosexual behaviour was selfreported in the community survey, and such behaviour was given a frequency but no context in the seroprevalence study. Evidence and a description of the range and expression of male same-sex behaviour was developed from the ethnicity field research. There are many other examples of how the power of this research was increased by the use of a multidisciplinary approach that merged quantitative and qualitative methods. The union of the two approaches was far more compelling than any single component, and although hardly easy to achieve it was well worth the effort. Disease prevention efforts should challenge the complexity of the real-life, human setting of AIDS and other illnesses, and require that investigators shed the narrow illusion that life and death can be fragmented and reduced into academic disciplines and re-constructed

intelligibly again. George A Gellert Project HOPE, Millwood, VA 22646, USA 1 Gellert GA, Moore DF, Maxwell RM, Mai KK, Higgins KV. Targeted HIV seroprevalence among Vietnamese in southern California. Genitourinary Med (in press). 2 Carrier J, Nguyen B, Su S. Vietnamese American sexual behaviors and HIV infection. J Sex Res 1992; 29: 1-14.

procedure can be done on any patient (one case weighed 173-5 kg), not something one can say about LC. In Canada a study such as McMahon’s could never have been mounted. Media, commercial, primary care physician, and patient pressure were too overwhelming. But at the

beginning, a shortage of equipment did allow me to do some MC cases. The retrospective data may be of interest. In my first 114 LCs, 5 were converted to open operation because of operative difficulties and 3 others were converted due to equipment failure, making a total conversion rate of 7 %. This left 106 cases for comparison with 16 MCs in the same period. I found no significant difference in hours in hospital (counting from completion of skin closure). For LC this was 58 h (range 17-695) and for MC it was 96 (36-288). There was a significant difference in operative time (skin to skin) (92 [34-238] min for LC vs 75 [45-112] min for MC). In 9 MC cases cholangiograms were done, and in 1 MC a stone was removed bileduct. Thus the two groups are not strictly comparable since operation times were often lengthy due to inexperience with LC, while cholangiograms and a duct exploration lengthened the time for MC. The only duct complication was one cystic duct slough in the LC group. All the MC patients were sent home with paracetamol and codeine medication, but many of the LC group needed this too. With any operation, I sometimes find that back-to-work times depend on whether or not the patient is self-employed and whether or not he or she is compensated for time lost. I make no claim for the scientific validity of the results above, but they suggest that while there may be a mathematical difference between the two operations, it is small in practical terms, if a real "mini" operation is used. Further, since MC is an extension of longstanding operative techniques, the unprecedented number of major duct and other injuries are not seen. One pauses to wonder about the incidence of common duct injury during the first 20 or 30 years of experience with classic cholecystectomy. The only "high tech" equipment one must have for MC is a good headlight. Does the much greater cost in financial terms and the personal cost of the high major complication rate really justify this passionate affair with the new technology? The consuming public of this Canadian province (and probably everywhere else) is unconvinced by the subtleties and niceties of such arguments. Lay and "pseudomedical" press propaganda is all pervasive. Thus, I continue to perform LC almost without exception. It is good to know, however, that if and when the cost crunch comes there is something pretty good to fall back on. from the

common

Julius L Stoller Suite 316, 888 West 8th Avenue, Vancouver, BC V5Z 3Y1, Canada

Cholecystectomy choices in 1994 SIR—Older Lancet readers who remember the British The Brains Trust might agree that if Prof C E M Joad had been asked about the article comparing laparoscopic cholecystectomy (LC) and minilaparotomy cholecystectomy (MC) by McMahon and colleagues (Jan 8, p 135) he would have begun his answer by saying, "It all depends on what you mean by minilaparotomy

Broadcasting Corporation’s

cholecystectomy". The operation being compared with LC cannot be called a "minilaparotomy cholecystectomy", especially for the 10% of cases in which the wound was more than 10 cm long. An operation with an incision greater than 6 cm does not merit the appellation "mini". My own bias is towards a 5-6 cm midline

epigastric incision which begins

at

the

tip

of the

xiphoid.

The

linea alba is opened, and the extraperitoneal areolar tissue pushed away from under the right leaf, so that the peritoneal

cavity is entered

to

the

right

of the falciform

ligament.

This

Intracerebroventricular morphine, analgesia, and nociceptive spinal reflexes SIR—Although our knowledge of opioid receptors and pain mechanisms has greatly increased, to a large extent the neural substrates involved in the mechanisms of morphine-induced analgesia in human beings are still to be determined. In normal subjects it has been shown that intravenous morphine depressed dose-dependently (in the 01-035 mg/kg range) nociceptive flexion reflexes (Rm reflexes) and pain sensations elicited by sural nerve stimulation, whereas lower doses (0-05-0-03 mg/kg) had no effect.’ In paraplegic patients (spinal section of traumatic origin), intravenous morphine depressed Rm reflexes more powerfully than in normals. By contrast, when administered epidurally in patients with postoperative pain, 0-03 mg/kg morphine produced pain-relief parallel with a 857