An investigation of nine Malaysian dart poisons has confirmed that their main active components are cardenolides from Antiaris toxicaria (Pers.) Lesch. and alkaloids probably from different forms of Strychnos ignatii P. Bergius. It is not possible to determine the ethnic origin of the poisons from the results of the analyses on their own. Two new cardiac glycosides have been isolated and their structures determined as 12 beta-hydroxycannogenin 3 beta-O-beta-D-deoxygulopyranoside and 3 beta-O-alpha-L-rhamnopyranoside, respectively.
Published data on oxalate poisoning in domestic animals are reviewed, with a focus on tolerance and performance. Oxalic acid is one of a number of anti-nutrients found in forage. It can bind with dietary calcium (Ca) or magnesium (Mg) to form insoluble Ca or Mg oxalate, which then may lead to low serum Ca or Mg levels as well as to renal failure because of precipitation of these salts in the kidneys. Dietary oxalate plays an important role in the formation of Ca oxalate, and a high dietary intake of Ca may decrease oxalate absorption and its subsequent urinary excretion. Oxalate-rich plants can be supplemented with other plants as forage for domestic animals, which may help to reduce the overall intake of oxalate-rich plants. Non-ruminants appear to be more sensitive to oxalate than ruminants because in the latter, rumen bacteria help to degrade oxalate. If ruminants are slowly exposed to a diet high in oxalate, the population of oxalate-degrading bacteria in the rumen increases sufficiently to prevent oxalate poisoning. However, if large quantities of oxalate-rich plants are eaten, the rumen is overwhelmed and unable to metabolize the oxalate and oxalate-poisoning results. Based on published data, we consider that <2.0% soluble oxalate would be an appropriate level to avoid oxalate poisoning in ruminants, although blood Ca level may decrease. In the case of non-ruminants, <0.5% soluble oxalate may be acceptable. However, these proposed safe levels of soluble oxalate should be regarded as preliminary. Further studies, especially long-term studies, are needed to validate and improve the recommended safe levels in animals. This review will encourage further research on the relationships between dietary oxalate, other dietary factors and renal failure in domestic animals.
An unusual case of accidental poisoning with Dhatura seeds {sp. Datura stramonium; Syn: Thorn apple) is reported. Its clinical features are essentially due to its peripheral anticholinergic actions and are briefly discussed.
The latex of pokok ipoh (Antiaris toxocaria) and the root bark of akar ipoh (Strychnos species) have been the main sources of the poisonous principles in dart and arrow poisons prepared throughout south-east Asia. We report a fatal case of rhabdomyolysis and acute oliguric renal failure following oral ingestion of blowpipe dart poison. To our knowledge this is the first such report.
To assess dermal absorption of nicotine from tobacco leaves in relation to Green Tobacco Sickness (GTS), urinary cotinine concentrations were measured in 80 male tobacco-growing farmers and in 40 healthy males (controls) who did not handle wet tobacco leaves in Kelantan, Malaysia. Among non-smokers, urinary cotinine levels in farmers were significantly higher than those of controls; farmers with urinary cotinine of 50 ng/ml/m2 or above showed eye symptoms more frequently than those below this level (p<0.05). Farmers who did not wear protective equipment had subjective symptoms more frequently than those who used the equipment (p<0.05); some of these symptoms were seen more frequently in organophosphate (Tamaron) users than in non-users. As tobacco farmers evidence a risk of nicotine poisoning from tobacco leaves, assessment including GTS together with effects of pesticides will be necessary.
Changes in the buccal mucosa of 296 Indian and Malay betel-nut chewers in Perak, West Malaysia, were studied clinically. 167 out of 212 Indian subjects incorporated tobacco in their quids, while 45 out of 84 Malay subjects incorporated. "Gambir". The Indians appeared to show a higher proportion of mucosal changes, particularly when tobacco was used. "Gambir" did not appear to be potent in the production of mucosal changes. Comparison with studies in other parts of the world suggested comparable findings with respect to both tobacco and non-tobacco chewing samples, and there would appear to be some evidence that tobacco-containing quids are likely to produce a higher proportion of mucosal changes as compared to non-tobacco-containing quids. An attempt to demonstrate a dose-effect relationship by dividing the subjects into "slight" and "heavy" chewers did not yield significant differences between these two categories in each of the groups.
A survey was conducted to document and bring attention to the use of smokeless tobacco among rural Kadazan women in Sabah, East Malaysia. Of the 472 women interviewed, 59.5% had used tobacco among the ingredients that they habitually chewed. Women with low education were more likely to be chewers. The chewing habit was usually acquired during the teenage years and the practice was perceived mainly as a cultural norm. 73.3% of these smokeless tobacco users were unaware of any adverse health effect of this type of tobacco use as compared to 53.9% of the non-tobacco users. The high prevalence of smokeless tobacco use is easily maintained as tobacco is cheap, locally produced and its use is socially accepted. The low level educational status of the women compounds the problem and intervention programs to curb this form of tobacco use is warranted.
As part of a larger study to bring attention to smoking and smokeless tobacco use among the indigenous people of Sabah State in Malaysia, the Bajaus were interviewed in a cross-sectional survey. 74.4% of the men smoked compared to 3.3% of the women and 77% of women used smokeless tobacco compared to 4.3% of men. Local handrolled cigarettes called kirais were popular and smokeless tobacco was used as an ingredient in the ritual of betel-quid chewing. Tobacco was also used because it was thought to have medicinal effects. The prevalence of smokeless tobacco use was significantly lower among the better educated women but for smoking, education had no relation with prevalence. Both habits could be easily maintained as they were cheap practices which were socially and culturally accepted. Awareness of the adverse effects of such tobacco habits was poor and intervention programs to curb tobacco use is required.
At the Faculties of Dentistry in Chiang Mai, Thailand (CM), and Kuala Lumpur, Malaysia (KL), 234 and 233 consecutive out-patients of mean ages 33.8 and 31.0 yr, respectively, were examined for the presence of oral mucosal lesions. Tobacco in some form was regularly used by 31.7% and 27.5% of the study populations in CM and KL, respectively. Cigarette smoking was the predominant habit. In CM three persons chewed betel quids and nine smoked banana leaf cigars daily. In addition, there were 24 habitual chewers of tea leaves (miang). In KL six persons chewed betel quids daily. In CM and KL three cases each (1.3%) of tobacco-associated leukoplakias were found. In KL an additional idiopathic leukoplakia was registered. One and three cases of betel related lesions were found in CM and KL, respectively. One case of a squamous cell carcinoma was found in a 45-yr-old Indian woman in KL who had been chewing betel with tobacco daily for many years. High prevalence figures were found for lichen planus, 3.8% in CM and 2.1% in KL, and an extremely high one, 48.3%, in CM for episodes of aphthous ulcers experienced during the last 2 yr. Comparatively low prevalence figures were found for herpes labialis. As could be expected melanin pigmentation was prevalent while only low figures were encountered for denture-related lesions and amalgam tattoos.
A variety of betel/areca nut/tobacco habits have been reviewed and categorized because of their possible causal association with oral cancer and various oral precancerous lesions and conditions, and on account of their widespread occurrence in different parts of the world. At a recent workshop in Kuala Lumpur it was recommended that "quid" be defined as "a substance, or mixture of substances, placed in the mouth or chewed and remaining in contact with the mucosa, usually containing one or both of the two basic ingredients, tobacco and/or areca nut, in raw or any manufactured or processed form." Clear delineations on contents of the quid (areca nut quid, tobacco quid, and tobacco and areca nut quid) are recommended as absolute criteria with finer subdivisions to be added if necessary. The betel quid refers to any quid wrapped in betel leaf and is therefore a specific variety of quid. The workshop proposed that quid-related lesions should be categorized conceptually into two categories: first, those that are diffusely outlined and second, those localized at the site where a quid is regularly placed. Additional or expanded criteria and guidelines were proposed to define, describe or identify lesions such as chewer's mucosa, areca nut chewer's lesion, oral submucous fibrosis and other quid-related lesions. A new clinical entity, betel-quid lichenoid lesion, was also proposed to describe an oral lichen planus-like lesion associated with the betel quid habit.
The prevalence and associated aetiologies of tooth wear were investigated in three ethnic groups in Sabah (Northern Borneo) using the Tooth Wear Index (TWI). The number of surfaces with enamel wear only, dentine exposed for less than a third or dentine exposed for more than a third were categorised into the TW minimal, moderate or severe respectively. A structured questionnaire was used to elicit medical/dental history, oral hygiene practices, satisfaction with body image, diet and other personal habits/details. The sample comprised of a self selected sample of 148 dental hospital attenders; 47 (32 per cent) each of ethnic Chinese and Malay and 54 (36 per cent) of ethnic Kadazan, matched for age and with a similar number of scoreable teeth per subject. Dentine exposure within the total sample was a common finding (95 per cent TW with moderate, 41 per cent TW severe). The Kadazan group had significantly (P < 0.05) more surfaces with severe tooth wear than the Chinese or Malay. Tobacco chewing was positively associated (rho = +0.4, P < 0.05) with both moderate and severe tooth wear, as was the habit of crushing/eating bones. Neither carbonated beverages or fresh fruit intake were associated with tooth wear, but their frequency of consumption was low. The buccal and occlusal surfaces of the posterior teeth were the most severely worn. Generally, wear was greater in the upper anterior sextant compared to the lower anterior sextant, with the exception of the lower incisal edges in the Kadazan group. Tooth wear into dentine was a common occurrence, especially among the Kadazan subjects and least among the Chinese subjects. The aetiological factors associated with this tooth wear are different to those encountered in Western cultures.
At the faculties of dentistry in Chiang Mai, Thailand (CM), and Kuala Lumpur, Malaysia (KL), 234 and 233 consecutive out-patients were interviewed concerning tobacco and chewing habits and examined for the presence of oral melanin pigmentation. Tobacco was regularly used by 32% and 28% of the studied populations in CM and KL. Cigarette smoking was the predominant habit, but the chewing of betel and tea leaves (miang) and the smoking of banana leaf cigars (khi yo) was also registered. The genetically acquired pigmentation dominated. Although nearly all non-tobacco users in the Malay and Indian populations had oral melanin pigmentation, it was found that tobacco smokers had significantly more oral surfaces pigmented than non-tobacco users. Among Thais, the percentage of pigmented individuals was significantly higher among tobacco smokers. It was concluded that tobacco smoking stimulates oral melanocytes to a higher melanin production also in dark-skinned ethnic groups.
This is an update on cultural and dietary risk factors for oral precancer and cancer. It is an overview on ethnic differences (where possible) and socio-cultural risk factors (tobacco/areca nut/betel quid, alcohol use and dietary factors) in relation to oral precancer and cancer. While studies were from Western countries, India and China, this update also attempts to include and highlight some studies conducted in the Asia-Pacific region.