Temporal patterns of charcoal burning suicides among the working age population in Hong Kong SAR: the influence of economic activity status and sex.

BACKGROUND: Charcoal burning in a sealed room has recently emerged as the second most common suicide means in Hong Kong, causing approximately 200 deaths each year. As charcoal burning suicide victims have a unique sociodemographic profile (i.e., predominantly economically active men), they may commit suicide at specific times. However, little is known about the temporal patterns of charcoal burning suicides. METHODS: Suicide data from 2001 to 2008 on victims of usual working age (20-59) were obtained from the registered death files of the Census and Statistics Department of Hong Kong. A total of 1649 cases of charcoal burning suicide were analyzed using a two-step procedure, which first examined the temporal asymmetries in the incidence of suicide, and second investigated whether these asymmetries were influenced by sex and/or economic activity status. Poisson regression analyses were employed to model the monthly and daily patterns of suicide by economic activity status and sex. RESULTS: Our findings revealed pronounced monthly and daily temporal variations in the pattern of charcoal burning suicides in Hong Kong. Consistent with previous findings on overall suicide deaths, there was an overall spring peak in April, and Monday was the common high risk day for all groups. Although sex determined the pattern of variation in charcoal burning suicides, the magnitude of the variation was influenced by the economic activity status of the victims. CONCLUSION: The traditional classification of suicide methods as either violent or nonviolent tends to elide the temporal variations of specific methods. The interaction between sex and economic activity status observed in the present study indicates that sex should be taken into consideration when investigating the influence of economic activity status on temporal variations of suicide. This finding also suggests that suicide prevention efforts should be both time- and subgroup-specific.

Wildlife and the coal waste policy debate: proposed rules for coal waste disposal ignore lessons from 45 years of wildlife poisoning.

This analysis examines wildlife poisoning from coal combustion waste (CCW) in the context of EPA's proposed policy that would allow continued use of surface impoundments as a disposal method. Data from 21 confirmed damage sites were evaluated, ranging from locations where historic poisoning has led to corrective actions that have greatly improved environmental conditions to those where contamination has just recently been discovered and the level of ecological impacts has yet to be determined. The combined direct and indirect cost of poisoned fish and wildlife exceeds $2.3 billion, which is enough money to construct 155 landfills with state-of-the-art composite liners and leachate collection systems. This cost is projected to increase by an additional $3.85 billion over the next 50 years, an amount that would construct 257 landfills. Evidence revealed through this study indicates the following: (1) for the past 45 years, environmental damage has been a recurring theme with surface impoundment of CCW, (2) the National Pollutant Discharge Elimination System has not been effective in preventing serious environmental damage from CCW, (3) EPA's Regulatory Impact Analysis of the costs and benefits of pollution control options fails to include benefits of avoided damages to natural resources, specifically, poisoned fish and wildlife, and (4) surface impoundments pose unacceptably high ecological risks regardless of location or design. Regulators should no longer ignore rigorous science and the lessons from multiple case examples. EPA and the United States need to show leadership on this issue by prohibiting surface impoundments, particularly since the rise in coal use in developing countries is leading to the same CCW pollution problems on a global scale.

The contribution of charcoal burning to the rise and decline of suicides in Hong Kong from 1997-2007.

BACKGROUND: There has been scant research exploring the relationship between choice of method (means) of self-inflicted death, and broader social or contextual factors. The recent emergence and growth of suicide using carbon monoxide poisoning resulting from burning charcoal in an enclosed space (hereafter, "charcoal burning") was related to an increase in the overall suicide rate in Hong Kong. The growth of this method coincided with changing economic conditions. This paper expands upon previous work to explore possible relationships further. PURPOSE: This study aims to discern the role of charcoal burning in overall suicide rate transition during times of both economic recession and expansion, as captured in the unemployment rate of Hong Kong, and to examine whether there was evidence of an effect from means-substitution. METHODS: Age and gender specific suicide rates in Hong Kong by suicide methods from 1997 to 2007 were calculated. To model the transition of suicide rate by different methods, Poisson regression analyses were employed. RESULTS: Charcoal burning constituted 18.3% of all suicides, 88% of which involved individuals drawn from the middle years (25-59) of life. During both periods of rising and declining unemployment, charcoal burning played an important role in the changing suicide rates, and this effect was most prominent among for those in their middle years. Means-substitution was found among the married women during the period of rate advancement (1997-2003). CONCLUSIONS: Compared to others, working-age adults preferentially selected carbon monoxide poisoning from charcoal burning.

Residence in coal-mining areas and low-birth-weight outcomes.

The objective of this study was to estimate the association between residence in coal mining environments and low birth weight. We conducted a cross-sectional, retrospective analysis of the association between low birth weight and mother's residence in coal mining areas in West Virginia. Birth data were obtained from the West Virginia Birthscore Dataset, 2005-2007 (n = 42,770). Data on coal mining were from the US Department of Energy. Covariates regarding mothers' demographics, behaviors, and insurance coverage were included. We used nested logistic regression (SUDAAN Proc Multilog) to conduct the study. Mothers who were older, unmarried, less educated, smoked, did not receive prenatal care, were on Medicaid, and had recorded medical risks had a greater risk of low birth weight. After controlling for covariates, residence in coal mining areas of West Virginia posed an independent risk of low birth weight. Odds ratios for both unadjusted and adjusted findings suggest a dose-response effect. Adjusted findings show that living in areas with high levels of coal mining elevates the odds of a low-birth-weight infant by 16%, and by 14% in areas with lower mining levels, relative to counties with no coal mining. After covariate adjustment, the persistence of a mining effect on low-birth-weight outcomes suggests an environmental effect resulting from pollution from mining activities. Air and water quality assessments have been largely missing from mining communities, but the need for them is indicated by these findings.

Aberrant gene promoter methylation in sputum from individuals exposed to smoky coal emissions.

BACKGROUND: Recent studies suggested the potential for aberrant gene promoter methylation in sputum as predictive marker for lung cancer. Here, the promoter methylation of p16, MGMT, RASSF1A and DAPK genes was investigated in sputum of individuals exposed to smoky coal emissions in Xuan Wei, China, where the lung cancer rate more than 6 times the Chinese national average. MATERIALS AND METHODS: Sputum DNA of 107 noncancer individuals and 58 lung cancer patients was screened for promoter methylation using methylation-specific PCR. RESULTS: Promoter methylation of the p16 gene was detected in about half [51.4% (55/107)] sputum DNA from noncancer individuals, a frequency higher than that observed for the RASSF1A (29.9%), MGMT (17.8%) and DAPK (15.9%) genes. Furthermore, the p16 gene was affected by promoter methylation at a frequency even higher among the lung cancer group, compared with the noncancer group [70.7% (41/58) versus 51.7% (55/107), p = 0.017]. CONCLUSION: Individuals exposed to smoky coal emissions in this region harbored frequent promoter methylation of these genes in their sputum and some of such alterations may be involved in lung tumor development.

A follow-up study of mortality among the arseniasis patients exposed to indoor combustion of high arsenic coal in Southwest Guizhou Autonomous Prefecture, China.

OBJECTIVE: This study was directed to ascertain the mortality of a group of arseniasis patients in an endemic rural township in Southwest China, where the residents were exposed for decades to indoor combustion of high arsenic coal. METHODS: All the diagnosed arseniasis cases registered in 1991 were defined as the target population, which were assigned to three symptom subgroups by the severity of dermal lesions. The death cases were surveyed and checked. The follow-up period was 12.5 years. The standardized mortality ratio (SMR) of all death causes combined, all cancers combined, and the cancers at every site were analyzed. The age standardized mortality rates (ASMRs) were calculated in three subgroups using the procedure of standardization. RESULTS: One hundred and six death cases were recorded. Liver cirrhosis, non-melanotic skin cancer, lung and liver cancer were the four most prevalent death causes and referred to 70.8% (75/106) of the total death cases. The mortality of all death causes combined was not higher than that of the whole of China in 2001 (SMR = 0.76, 95% CI 0.63-0.93). The crude mortality rate of non-melanotic skin cancer in males reached up to 128.66/10(5). SMRs of lung cancer and larynx cancer in males (SMRs 2.84 and 27.27, 95% CIs 1.51-4.86 and 5.61-79.62, respectively) significantly exceeded the levels for all male Chinese. ASMRs of all death causes combined, all cancers combined and non-melanotic skin cancer in males of the severe dermal symptoms subgroup were significantly higher than those in medium and/or mild dermal symptom subgroups. CONCLUSIONS: A significantly increased mortality due to lung cancer and non-melanotic skin cancer was confirmed, alike the situation in other arseniasis endemic areas in the world. No significant elevation of mortality due to liver cancer and bladder cancer was observed. Male arseniasis patients diagnosed with severe skin lesions face higher risks of malignancies and of non-melanotic skin cancer in particular in the following years.

A global health problem caused by arsenic from natural sources.

Arsenic is a carcinogen to both humans and animals. Arsenicals have been associated with cancers of the skin, lung, and bladder. Clinical manifestations of chronic arsenic poisoning include non-cancer end point of hyper- and hypo-pigmentation, keratosis, hypertension, cardiovascular diseases and diabetes. Epidemiological evidence indicates that arsenic concentration exceeding 50 microg l(-1) in the drinking water is not public health protective. The current WHO recommended guideline value for arsenic in drinking water is 10 microg l(-1), whereas many developing countries are still having a value of 50 microg l(-1). It has been estimated that tens of millions of people are at risk exposing to excessive levels of arsenic from both contaminated water and arsenic-bearing coal from natural sources. The global health implication and possible intervention strategies were also discussed in this review article.

Ventilatory function of progressive massive fibrosis among bituminous coal miners in Taiwan.

Geographic and ethnic differences exist for the effects of respirable coal-mine dust on the lung function of miners. In this study, the authors compared 177 coal workers who had radiological evidence of progressive massive fibrosis (PMF) with 87 healthy male control subjects. The authors performed maximal expiratory flow volume measurements, single-breath carbon monoxide diffusing capacity (DLco) measurements, and arterial blood gas analysis on each subject. The data revealed that miners with early PMF (category A) had significantly reduced, but well-preserved, vital capacity (VC) and forced expiratory volume in 1 sec (FEV1.0), whereas FEV1.0/VC and DLco were decreased in both nonsmokers and smokers. Abnormally low (i.e., < 80% of predicted values) VC and FEV1.0, and further decreases in DLco, were observed in miners with late PMF (categories B and C). The predominant impairment patterns for workers in categories A, B, and C were obstructive, obstructive and mixed, and mixed and restrictive, respectively. Smoking increased the magnitude of airway obstruction. The authors concluded that diversity in functional impairment was present among bituminous coal miners, even among those with PMF.

Pico de fluxo expiratório em trabalhadores de fábricas de fogos de artifício / Expiratory peak flow in employees of firework factories

A pólvora é uma mistura explosiva constituída por 75 por cento de salitre (nitrato de potássio), 12 por cento de carväo e 13 por cento de enxofre, moídos em conjunto. O objetivo deste trabalho foi verificar um possível acometimento das vias aéreas de trabalhadores de fábricas de fogos de artifício por pólvora inalada. Foram medidos os picos de fluxo expiratório de 234 pessoas do Município de Santo Antônio do Monte, Minas Gerais: 41 sem exposiçäo profissional à pólvora (grupo controle) e 193 trabalhadores de fábricas de fogos de artifício. Os parâmetros utilizados foram: idade, sexo, estatura, peso, tabagismo e tempo de exposiçäo à pólvora. Todos os indivíduos pertencentes ao grupo controle tiveram seus níveis de pico de fluxo expiratório dentro da normalidade. Em 50 (25,9 por cento) trabalhadores houve reduçäo desse fluxo, sendo que 34 (68 por cento) eram tabagistas, 10 (20 por cento) tinham entre 5 e 10 anos de exposiçäo e 10 (20 por cento) tinham mais de 10 anos de exposiçäo. Concluindo, a pólvora parece ser um fator relacionado à reduçäo de pico de fluxo expiratório, principalmente em indivíduos tabagistas.

Alveolar macrophages modulate the epithelial cell response to coal dust in vitro.

The response of the alveolar epithelium to coal dust exposure is poorly understood. Coal or other dusts may act on the epithelium directly or indirectly through nearby alveolar macrophages (AM) that produce cytokines and other soluble products. AM and type II pneumocytes (T2P) were thus exposed to dust in coculture to evaluate their possible interactions. Anthracite coal dust PSOC 867 increased synthesis of extracellular matrix (ECM) components by T2P. AM alone did not produce ECM. Similarly, coculture of T2P with AM (3.75:1) had little effect on epithelial ECM synthesis. In contrast, coculture of T2P with AM significantly increased PSOC 867 effects on T2P rates of ECM synthesis, ECM fibronectin content, and T2P levels of fibronectin mRNA. AM-conditioned medium did not change the PSOC 867 effect on T2P. Neither control nor PSOC 867-treated AM on Falcon culture inserts (0.45-micron pore size) over T2P stimulated ECM synthesis by either untreated or dust-exposed epithelium. Thus AM-mediated changes in ECM synthesis by PSOC 867-treated T2P require close cell-cell interactions, suggesting a role for cell-cell contact or for short-lived soluble mediators of the AM effects.