Accidental paraquat poisonings

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Information Section

ratio (SIR) 1.91, 95% CI 1.65-2.21] in comparison with the general female Norwegian population. The investigators suggested that, in view of the high iodine content of fish and other seafoods, the consumption of such foods was the likely underlying cause (Frich L. et al., British Journal of Cancer 1997, 76, 385).

Trans-fatty acids and breast cancer A study of postmenopausal women from five European countries has suggested an association between the risk of breast cancer and the levels of trans-fatty acids stored in the adipose tissue. Samples of fat from the buttocks of 209 women with primary breast cancer and 407 controls were analysed. Women with higher trans-fatty acid levels were more likely to have developed breast cancer, although the effect appeared to be confined to those individuals with the lowest levels of polyunsaturated fat (Kohlmeier L. et al., Cancer Epidemiology, Biomarkers and Prevention 1997, 6, 705). Phytoestrogens may protect against breast cancer The risk of breast cancer was found to be substantially reduced among Australian women with a high dietary intake of natural oestrogens, particularly the isoflavone, equol, and the lignan, enterolactone. The study involved 144 women with newly diagnosed early breast cancer and the same number of randomly selected controls. Urinary excretion of phytoestrogens served as a measure of intake. For equol, the adjusted odds ratio (OR) for the highest quartile of excretion (compared with the lowest quartile) was 0.27 [95% confidence interval (CI) 0.10-0.69]. For enterolactone, the equivalent adjusted OR was 0.36 (95% CI 0.150.86]. The investigators discussed the various limitations of their study, but concluded that ~these findings could be important in the prevention of breast cancer" (Ingram D. etal., Lancet 1997, 350, 990).

Protective effect of phytoestrogens against prostate cancer?. An Australian professor describes how a medical practitioner with prostate cancer took a daily phytoestrogen preparation (4 x 40 mg Promensil tablets, made from red clover) for 7 days before having his prostate removed. The organ showed degenerative changes typical of a response to high-dose oestrogen therapy and suggestive of tumour regression. The professor concludes that "studies of the effects of phytoestrogens in prostate cancer may be warranted" (Stephens F.O., Medical Journal of Australia 1997, 167, 138).

Genistein enhances colon cancer in rats This soybean isoflavonoid given at 250 ppm in the diet of rats (about 12 mg/kg body weight/day) for just over 1 year enhanced the development of colon cancer (number of tumours per rat or turnoutbearing rat) induced by a known carcinogen. The US investigators noted "these observations are in sharp contrast to earlier findings that genistein has anticarcinogenic and antiproliferating activities" and "emphasize that the biological effects.., may be organ specific, inhibiting cancer development in some sites yet showing no effect or an enhancing effect on the tumorigenesis at other sites" (Rao C.V. et al., C.ancerResearch 1997, 57, 3717).

Salt and blood pressure in the elderly A trial in a London hospital has demonstrated that a "modest" reduction in sodium intake can lower blood pressure not only in elderly volunteers who are hypertensive, but also in those with a blood pressure in the normal range. The double-blind crossover trial involved 47 volunteers (18 normotensive, 29 hypertensive; average age 67 years) who consumed a diet with a reduced level of sodium (around 5 g/day), or a diet containing the average UK levels (10 g/day), each for a period of 4 weeks. The investigators felt that reductions in blood pressure they observed (over 3 mmHg diastolic) could result in "a major reduction in strokes..." (Cappuccio F.P. et aL, Lancet 1997, 350, 850).

The dangers of binge beer-drinking In a Finnish study of middle-aged male beer drinkers, the risk of death from a heart attack was significantly higher for 70 men who usually drank six or more bottles of beer per session than it was for 1151 more moderate drinkers (who favoured less than three boules/session), even after adjustment for total average consumption of beer and other alcoholic drinks [relative risk (RR) 6.5, 95% CI 2.1-20.6] (Kauhanen J. et aL, British Medical Journal 1997, 315, 846). {Ref: 103972}

Colitis in a human consuming royal jelly A 53-year-oldJapanesewoman suffered abdominal pain and bloody diarrhoea after consuming 10 ml royal jelly/day for 25 days. Colonoscopy examination revealed damage (haemorrhaging, oedema, inflammation, infiltration of inflammatory cells, and platelet aggregation) CYoneiY. et al., Journal of Gastroenterology andHepatology 1997, 12, 495).

Accidental paraquat poisonings An analysis of the circumstances surrounding 15 deaths from paraquat poisoning among farmers or labourers in Costa Rica emphasizes the highly toxic

Information Section nature of this pesticide and the extreme care with which it should be handled. Three deaths involved sprayers (one with a leaking backpack, one whose face was soaked with the pesticide after he sprayed into the wind, and a third with no exceptional exposure circumstances). A 10-year-old boy died with minor skin lesions on his legs after working in a sprayed plantation. Two other deaths resulted from spillages of the concentrate on the legs or of the dilute solution on face and mouth. The remaining nine deal,s were due to the ingestion of paraquat, five after drinking a mouthful of the concentrate (because of a confusion of bottles), another two after eating with contaminated hands, one after drinking water from a used measuring cup, and one after transferring paraquat concentrate by sucking through a hose. The Swedish investigators noted that the addition of colouring and stenching compounds to the commercial formulation of paraquat in 1987 *has contributed substantially to pre~¢ent the most extreme oral exposures" (all fatalities associated with confusion of bottles occurred before 1987). However, fatal paraquat poisoning.,;from dermal or low-dose oral exposure are still a serious risk "under circumstances that .,~pposedly should not imply major health risks" (Wesseling C. et al., American Journal of Industrial Medicine 1997, 32, 433).

Low dose effecll of malathion in mice In a 90-day study conducted in the US, this widely used pesticide produced mast cell degranulation in the skin, peritoneura and uterus and subtle effects on the lungs of female mice given 0.1 mg/kg body weight/day by stomach tube, the lowest dose tested (Rodgers K. and Xiong S., Toxicology Letters 1997, 93, 73).

Miconazole genatoxic in mice An Egyptian investigator reports that this antifungal agent produced dose-related increases in abnormal sperm and in chromosome damage in the bone marrow and primary spermatocytes, when given at low doses by intraperitoneal injection to mice (t'Iassan N.H.A., Journal of Applied Toxicology 1997, 17, 313).

I, I -Dichloro- 1-fluoroethane kills worker 1,1-Dichloro-l-fluoroethane, a potential replacement for trichlorofluoromethane (CFC-11) in foam-blowing operations and as a cleaning agent, caused death in a 40.year-old man using the pure solvent to clean a degreasing tank. Postmortem examination revealed a violet coloration of the face, swelling of the face and lungs, and increased concentrations of the solvent especially in the

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blood, liver and heart. Considering the potential for exposure in humans as its use increases, the investigators called for studies on, and guidelines for, the safe handling of 1,1-dichloro-l-fluoroethane (Astier A. and Paraire F., New England ]ournal of Medicine 1997, 337, 940).

Toluene-induced hearing loss? Exposure to toluene has been associated with hearing loss in Brazilian printing workers who were occupationally exposed to various levels of noise and organic solvents. Around half of these 124 workers suffered from high-frequency hearing loss in both ears, and there was a significant association between this condition and a biological index of toluene exposure (urinary hippuric acid). The hearing defidts were occurring at biological exposure levels below those considered acceptable by the ACGIH (Morata T.C. et aL, Scandinavian Journal of Work, Environment and Health 1997, 23, 289).

Occupational contact dermatitis from camosol "The first reported case of contact dermatitis from carnosol', a naturally-occurring compound present in rosemary, has been described in a 56-year-old man who had worked "for several years" in a food processing factory adding spices and additives to sausages. The patient developed severe dermatitis of the hands, forearms and face a few weeks after starting work with Rosmanox, an extract of the leaves of Rosemary. Patch tests with 5% Rosmanox in petrolatum and 0.1% pure carnosol in ethanol confirmed the sensitized state (Hjorther A.B. et al., Contact Dermatitis 1997, 37, 99). O c c u p a t i o n a l asthma from amylase... Enzymes are well recognized and potent inducers of occupational asthma, but the risks associated with using amylase in histopathology laboratories, evidently a widespread practice, are perhaps not fully appreciated. A case is presented of a UK laboratory technician who developed this disease, 4-6 months after he started using an anhydrous powder preparation of pig pancreatic amylase. The diagnosis was confirmed by double-blind challenges with the powder, which induced immediate and late asthmatic reactions (Aiken T.C. et aL, Occupational and Environmental Medicine 1997, 54, 762). ... a n d from isothiazoUnones A case report has been published describing the development of asthma in a man who was occupationally exposed to various isothiazolinone