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1.
Tobacco is a major Brazilian cash crop. Tobacco farmers apply large amounts of pesticides to control insect growth. Workers come into contact with green tobacco leaves during the tobacco harvest and absorb nicotine through the skin. In the present study, micronucleus frequency, cell death, and the frequency of basal cells were measured in tobacco farmers using the buccal micronucleus cytome assay (BMCyt), in parallel with measurement of blood butyrylcholinesterase (BChE) and nicotine levels. Polymorphisms in PONIGln192Arg and CYP2A6*9(?48T>G) were evaluated to verify the relationship between genetic susceptibility and the measured biomarkers. Peripheral blood and buccal cell samples were collected from 106 agricultural workers, at two different crop times (during pesticide application and leaf harvest), as well as 53 unexposed controls. BMCyt showed statistically significant increases in micronuclei, nuclear buds, and binucleated cells among exposed subjects in differentiated cells, and in micronuclei in basal cells. In addition, the exposed group showed higher values for condensed chromatin, karyorrhectic, pyknotic, and karyolitic cells, indicative of cell death, and an increase in the frequency of basal cells compared to the unexposed control group. A slight difference in mutagenicity using the BMCyt assay was found between the two different sampling times (pesticide application and leaf harvest), with higher micronucleus frequencies during pesticide application. Elevated cotinine levels were observed during the leaf harvest compared to the unexposed controls, while BChE level was similar among the farmers and controls. PONIGln192Arg and CYP2A6*9(?48T>G) polymorphisms were associated with DNA damage induced by pesticides and cell death. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
2.
In studying East Javanese peasant farmers it was found that workers with low energy intakes were as productive as workers with high energy intakes. Measurements indicated that work output produced by a given energy intake varied considerably in relation to the individual consumer and that the work efficiency of the consumer varied inversely in relation to the degree of undernutrition or energy stress. It appeared that there may have been compensatory mechanisms such as higher levels of metabolic efficiency, lower basal metabolic rates, greater physical fitness, or stronger incentives to work enabling those on a low energy diet to produce more work per unit energy intake than individuals with relatively high energy intakes.  相似文献   
3.

Context

The 5 major tobacco-growing states (Kentucky, North Carolina, South Carolina, Tennessee, and Virginia) are disproportionately affected by the tobacco epidemic, with higher rates of smoking and smoking-induced disease. These states also have fewer smoke-free laws and lower tobacco taxes, 2 evidence-based policies that reduce tobacco use. Historically, the tobacco farmers and hospitality associations allied with the tobacco companies to oppose these policies.

Methods

This research is based on 5 detailed case studies of these states, which included key informant interviews, previously secret tobacco industry documents (available at http://legacy.library.ucsf.edu), and media articles. This was supplemented with additional tobacco document and media searches specifically for this article.

Findings

The tobacco companies were particularly concerned about blocking tobacco-control policies in the tobacco-growing states by promoting a pro-tobacco culture, beginning in the late 1960s. Nevertheless, since 2003, there has been rapid progress in the tobacco-growing states’ passage of smoke-free laws. This progress came after the alliance between the tobacco companies and the tobacco farmers fractured and hospitality organizations stopped opposing smoke-free laws. In addition, infrastructure built by National Cancer Institute research projects (COMMIT and ASSIST) led to long-standing tobacco-control coalitions that capitalized on these changes. Although tobacco production has dramatically fallen in these states, pro-tobacco sentiment still hinders tobacco-control policies in the major tobacco-growing states.

Conclusions

The environment has changed in the tobacco-growing states, following a fracture of the alliance between the tobacco companies and their former allies (tobacco growers and hospitality organizations). To continue this progress, health advocates should educate the public and policymakers on the changing reality in the tobacco-growing states, notably the great reduction in the number of tobacco farmers as well as in the volume of tobacco produced.  相似文献   
4.
目的 探讨常见因素对留守村民体质指数( BMI)的影响. 方法 采用分位数回归等方法分析常见因素对BMI影响程度及趋势. 结果 随着BMI水平的增加,年龄对BMI的影响呈持续微弱下降趋势,在BMI 10%和90%分位数水平时回归系数(95%CI)分别为-0. 044( -0. 063,-0. 026)和-0. 029 ( -0. 050,-0. 009). 当BMI大于30%分位数后,性别对BMI的影响逐渐明显. 腰臀比与BMI呈正相关性,且相关性随着 BMI 的增加而增加. 在 BMI 的10%和90%分位数水平时回归系数( 95% CI )分别为 18. 024 (15. 454, 20. 594)、31. 716(28. 798,34. 633). 当 BMI 水平大于40%分位数时,体力活动量与BMI呈负相关性. 饮食指数与生活事件指数在BMI整个分位数范围内均呈正相关性,且饮食指数在BMI 80%分位数之前相关性较平稳(回归系数约为0. 830),之后急剧增加(回归系数最高达1. 267);而生活事件则呈现中间低两头高的趋势(回归系数最高为1. 164,最低为0. 714). 文化程度、吸烟史、饮酒史在BMI的整个分位数范围内均无相关性. 结论 常见因素对不同分位数水平BMI的影响有明显差异.  相似文献   
5.

Background

Globalization-related measures to liberalize trade and stimulate export production were applied in Uganda in the late 1980s, including in the coffee production sector, to revitalize agricultural production, increase incomes to farmers and improve rural food security.

Objective

To explore the different effects of such measures on the health and dietary outcomes of female coffee and food small holder farmers in Uganda.

Methods

We gathered evidence through a cross-sectional comparative interview survey of 190 female coffee producers and 191 female food producers in Ntungamo district. The study mostly employed quantitative methods of data collection, targeting the sampled households. We also utilized qualitative data; collected three months after the household survey data had been collected and their analysis had been accomplished. Using qualitative interviews based on an unstructured interview guide, extra qualitative information was collected from key informants at national, district and community levels. This was among other underlying principles to avoid relying on snapshot information earlier collected at household level in order to draw valid and compelling conclusions from the study. We used indicators of production, income, access to food and dietary patterns, women''s health and health care. Of the two groups selected from the same area, female coffee producers represented a higher level of integration into liberalised export markets.

Results

Document review suggests that, although Uganda''s economy grew in the period, the household economic and social gains after the liberalization measures may have been less than expected. In the survey carried out, both food and coffee producers were similarly poor, involved in small-scale production, and of a similar age and education level. Coffee producers had greater land and livestock ownership, greater access to inputs and higher levels of income and used a wider variety of markets than food producers, but they had to work longer hours to obtain these economic returns, and spent more cash on health care and food from commercial sources. Their health outcomes were similar to those of the food producers, but with poorer dietary outcomes and greater food stress.

Conclusions

The small-scale women farmers who are producing food cannot rely on the economic infrastructure to give them support for meaningful levels of production. However, despite having higher incomes than their food producing counterparts, the evidence showed that women who are producing coffee in Uganda as an export commodity cannot rely on the income from their crops to guarantee their health and nutritional wellbeing, and that the income advantage gained in coffee-producing households has not translated into consistently better health or food security outcomes. Both groups have limited levels of autonomy and control to address these problems.  相似文献   
6.
Over the last few years, the interest of decision‐makers and control agencies in biosecurity (BS), aiming at preventing and controlling the introduction and spread of infectious diseases, has considerably increased. Nevertheless, previous studies highlighted a low implementation level of biosecurity measures (BSM), especially in cattle farms; different reasons were identified such as perceived costs, utility, importance, increased workload and lack of knowledge. In order to convince cattle farmers to adopt BSM, it is necessary to gather more information and evidence on their cost‐effectiveness and their importance or utility in terms of disease prevention and control. The objectives of this study were to determine whether the farm or farmers’ profile correlated with the implementation level of BSM and if there was a positive correlation between the BSM implementation and the farm production and health parameters. Data were collected through face‐to‐face interviews conducted in 100 Belgian farms as part of a stratified and randomized survey. The Regional Animal Health Services provided the farm health status and production data. A general BS score and five sub‐scores related to the five BS compartments (bio‐exclusion, bio‐compartmentation, bio‐containment, bio‐prevention and bio‐preservation) were calculated for each farm based on the implementation level of different BSM grouped in 16 domains. The study highlighted a significant and negative correlation between the mortality rates in adult cattle (over 24 months of age) and young calves (aged 0–7 days) and different BS compartment scores. The study also demonstrated that the farms having a higher general BS score were indeed more likely to have a BVD‐free status. These evidence‐based findings are encouraging as they demonstrate the benefits of implementing BSM and could promote their adoption by farmers.  相似文献   
7.
This study aims to review agricultural pesticide usage and trends and to identify hazardous pesticides for regulation, in terms of public health, in South Korea. The authors collected data on usage and trends of agricultural pesticides through agriculture-related databases. Criteria from the US Environmental Protection Agency classification for carcinogenicity, World Health Organization classification for acute toxicity, and European Union prioritization list for endocrine-disrupting chemicals were used for the hazard categorization of identified individual active ingredients. Pesticides to be prioritized among all pesticides used in South Korea between 2007 and 2011 were selected by taking into account the volume of usage, toxicity, and epidemiological evidence. Annual agricultural use of pesticides has increased rapidly from the 1970s to 1990s in South Korea, but has declined since 2001. The quantity of pesticides used in 2011 was reported as 19,131 tons, and was comprised of 34.7% insecticides, 28.0% fungicides, and 27.1% herbicides. The 50 pesticides with the greatest volume of usage accounted for 82.6% of the total volume of pesticides used between 2007 and 2011, with the most-used active ingredient being machine oil, followed by mancozeb and then paraquat. Organophosphates were the most used among the top 50 pesticides. A total of 24 pesticides were selected for recommendation of intensive regulation in South Korea. In conclusion, the authors described the usage and trends of overall agricultural pesticides, which would serve as a fundamental step forward in managing pesticide in terms of public health. Intensive efforts are required for the prevention of potential health effects from the 24 identified pesticides.  相似文献   
8.
Farmers have a high rate of suicide (1% of suicides in England and Wales). This study sought to test whether farmers would be less likely to have been in contact with primary or mental health services before death due to their reluctance to seek help. The study also sought to identify other characteristics that differentiated suicide among male farmers from other professional groups. A retrospective case-control design was used comparing male farmers with an age and sex matched control group. Cases were all members of the farming community within the Exeter Health District on whom suicide or open verdict had been recorded between 1979 and 1994. 63 Cases were identified and entered into the study. Controls were non-farmers with the same verdict who were matched for age (5 year age bands) sex and social class. Farmers were significantly more likely to use firearms to kill themselves (42% of farmers v 11% controls). They were less likely to use a car exhaust or to die by poisoning (9% farmers v 50% controls). Farmers were significantly less likely to leave a suicide note (21% farmers v 41% controls). There was no significant difference between farmers and controls for numbers in contact with their general practitioner or mental health services in the 3 months before death. There may be some differences in help seeking behaviour between farmers and the general population as over 30% of farmers presented with exclusively physical symptoms. General practitioners should consider depressive and suicidal intention in farmers presenting with physical problems. When depression is diagnosed consideration should be given to the temporary removal of firearms as the high rate of suicide in the farming community may be strongly influenced by access to means.  相似文献   
9.
There are few studies on cancer risks among female farmers, particularly on breast cancer and cancer in female genital organs. We have conducted a cohort study of cancer risk among 50,682 women with occupations in agriculture according to the Swedish 1970 census. The cohort was followed up in the nationwide, populationbased, Cancer-Environment Register from 1 January 1971 until death or until 31 December 1987. Expected number of cases was based on annual cancer incidence in five-year age groups. The standardized incidence ratio (SIR) was computed as the ratio between observed and expected number of cases. A total of 4,474 cases of cancer were observed in the cohort from 1971 until 1987cf 5,273 expected, resulting in a significantly decreased SIR of 0.85 (95 percent confidence interval [CI]=0.82–0.87). SIR for breast cancer was significantly decreased (0.83, CI=0.78–0.88), as was the SIR for cervix uteri (0.40, CI=0.31–0.50). For the other female genital organs, SIR was close to one. Other cancer sites with significantly decreased SIRs were: colon (0.90, CI=0.81–1.00); rectum (0.86, CI=0.74–1.00); lung (0.46, CI=0.37–0.57); kidney (0.81, CI=0.68–0.97); urinary organs (0.57, CI=0.45–0.72); connective tissue and muscle (0.62, CI=0.39–0.95); and non-Hodgkin's lymphomas (0.78, CI=0.63–0.96).This study was supported by grant from Kungliga Skogs-och Lanthruksakademien.  相似文献   
10.
BACKGROUND: Personal protective equipment (PPE) is readily available and widely recommended, yet usage among agricultural workers is largely unknown. METHODS: A mail survey of 2,483 farmers in six Midwestern states with telephone follow-up addressed PPE usage related to sun exposure, noise abatement, chain saw usage, welding and metal work, handling of large animals in and out of confinement facilities, feed handling, manure storage facilities, and mixing and applying chemicals. Summary statistics of survey responses were compiled. RESULTS: With the exception of welding masks, PPE usage was low. Farmers were satisfied with availability of PPE through local hardware and farm cooperatives, but the decision to use PPE was personal and influenced little by outside parties. CONCLUSION: PPE usage rates by farmers on Midwestern farms need to be increased. The desire of the individual farmer to reduce risk of personal injury or exposure should be targeted. The most effective venue will be local agricultural extension services.  相似文献   
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