Maternal smoking and respiratory function in the newborn

Maternal smoking and respiratory function in the newborn

182 Information Section who reported at the start of the study to have never smoked and who remained non-smokers, only 127 (about 8%) had died. ~Of ...

90KB Sizes 2 Downloads 71 Views

182

Information Section

who reported at the start of the study to have never smoked and who remained non-smokers, only 127 (about 8%) had died. ~Of those alive at 20, an estimated 42% (95% C136-50%) of lifelong smokers would be alive at 73 compared with 78% (95% C174-82%) of lifelong non-smokers" (Phillips et al., British Medical ]ournal 1996, 313,907).

Maternal smoking and respiratory function in the newborn Investigators from Western Australia have reported reduced lung function in the newborn infants of mothers who smoked during pregnancy. Assessment of 461 infants (from an initial sample of 500) was undertaken typically when they were about 2 or 3 days old; 350 of the mothers daimed not to have smoked during pregnancy, while 39 of the 111 smokers admitted to a habit of more than 10 cigarettes a day. A clear dose response was observed (Stick et aL, Lancet 1996, 348, 1060).

Environmental tobacco smoke and coronary heart disease A new and large US study has shown that people exposed to environmental tobacco smoke 0iTS) in the home have about a 20% increased risk of dying from coronary heart disease (CHD). About 310,000 American married couples with one spouse who had never smoked were followed from 1982 to 1989, during which time there were 3819 deaths among the ~never-smokersL The risk of death from C H D was higher both in males (RR 1.22, 95% CI 1.07-1.40) and females (RR 1.10, 95% CI 0.96-1.27) exposed to a spouse's cigarette smoke. These findings were consistent whether exposure was determined by smoking habits reported by the spouse or by self-reported exposure or when both sources were used together. There were, however, no consistent dose-response trends and the investigators concluded that the data are "possibly subject to confounding by unmeasured risk factors" (Steenland et aL, Circulation 1996, 94, 622).

Allergenic threat of natural latex in air A range of apparently innocuous activities including walking near heavy traffic and being exposed to new rubber-soled shoes elicited symptoms of hypersensitivity (nasal congestion and swollen, red eyes) in a German secretary. Particularly severe symptoms developed after cleaning the roller of her typewriter. Skin prick tests with natural latex and exposure to airborne rubber particles confirmed natural latex hyper-

sensitivity. This case history led the investigators to express some concern about the allergenic impact of the natural latex that would be present in urban air (Rueff et al., Contact Dermatitis 1996, 35, 46).

DNA damage and carcinogen mixtures "[DNA damage] by a particular carcinogen can be significantly higher when administered in the form of a mixture than administered individually" according to investigators from the University of Kentucky Medical Center, USA. The polynuclear aromatic hydrocarbons benzo[a]pyrene, cyclopenta[c,d]pyrene or benzo[k]fluoranthene were given to mice by intraperitoneal injection either individually or as a mixture. Using a highly sensitive radiolabelling technique, DNA-reactive metabolites were detected in the serum at 7-20-fold higher levels when the chemicals were administered as a mixture rather than as individual compounds. Accumulation of DNA adducts in lung, liver and heart tissue was 1.5- to twofold higher with the mixture (Arif and Gupta, Carcinogenesis 1996, 17, 2213).

The human patch test--panel selection Further evaluation of the human 4-hr patch test, a likely replacement for the Draize rabbit skin test, has examined the effect of clinical hypersensitivity (or atopic status) on responses to three irritant substances [20% sodium dodecyl sulfate (SDS), 10% hydrochloric acid and 35% cocotrimethyl ammonium chloride]. Although reactions to the SDS were significantly more frequent in the 30 atopics than in the 28 non-atopic volunteers, the general ranking of the test materials were the same in both groups and it was concluded that there was no evidence that the routine selection of test panels should deliberately include or exclude atopics (Basketter et aL, Contact Dermatitis 1996, 35, 33).

Validation of alternative test methods Drawing from the experience of recent large-scale validation exercises for alternative test methods, a group of investigators involved in the testing of cosmetics has drawn up ~a practical process that can be used to conduct future validation programmes." In particular, they emphasize the importance of having a clearly stated prediction model before the validation study begins, so that objective comparisons can be made between the predicted and the actual study results (Bruner et aL, Toxicology in Vitro 1996, 10, 479).