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1.

Objective

To examine whether smoking onset in young adolescents is predicted by peer or parental smoking.

Design

Longitudinal design with one pretest and one follow‐up at 12 months.

Setting

Schools in Finland, Denmark, the Netherlands, the United Kingdom, Spain and Portugal.

Participants

7102 randomly selected adolescents from six countries. Mean age was 12.78 years.

Main outcome measures

Smoking behaviour of adolescents, peers and parents.

Results

No support was found for peer smoking as an important predictor of smoking onset in most countries. Support was found for the selection paradigm, implying that adolescents choose friends with similar smoking behaviour. Support for the impact of parents on adolescent behaviour and the choice of friends was also found.

Conclusions

Smoking uptake in this age cohort may be more strongly influenced by personal and parental influences than initially believed. Hence, social inoculation programmes teaching youngsters to resist the pressures to smoke may be less appropriate if youngsters have a positive attitude towards smoking, associate smoking with various advantages and look for peers with similar values. For this group attitudes towards smoking may thus guide future friend selection.  相似文献   

2.
OBJECTIVE—To examine how deeply foreign cigarette advertising had penetrated the Chinese market when a new ban on cigarette advertising was enacted in February 1995.DESIGN—A survey using self-completion questionnaires administered in college classrooms from November 1994 to March 1995.SETTINGS—Eight universities and four medical schools in three Chinese cities: Beijing, Wenzhou, and Hangzhou.SUBJECTS—1896 college students who agreed to complete a written questionnaire. The mean age was 21.2 years; 39.5% of respondents were female.RESULTS—Four of the top eight cigarette brands most familiar to the respondents were foreign: Marlboro, 555, Kent, and Hilton. Advertisements for the foreign brands were much more likely to be seen than those for the domestic brands; those for Marlboro were reported most often (29.7%), followed by 555 (21.8%) and Kent (18.1%). Among smokers, Marlboro was the most preferred foreign brand, by 44.2%. The preference for Marlboro was also correlated with smokers having seen its advertisements. Most respondents, 71.8%, believed that cigarette advertising should be banned.CONCLUSIONS—The previous restrictions on cigarette advertising in China failed to prevent a large portion of the population from seeing and understanding the advertisements. Before the 1995 advertising ban took effect, strict limitations on imports of foreign cigarettes notwithstanding, certain highly advertised brands such as Marlboro achieved wide recognition and even consumer preference. Stricter restrictions are suggested as previous ones have failed to achieve their intended effects.  相似文献   

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OBJECTIVE: To evaluate awareness and knowledge of cigarette filter ventilation in a national probability sample of smokers of Ultra-light, Light, and regular cigarettes. DESIGN: Random-digit-dialling and computer-assisted telephone interviewing was used on a probability sample of daily cigarette smokers (ages 18 and above). SUBJECTS AND SETTING: 218 Smokers of Ultra-light cigarettes, 360 smokers of Light cigarettes, and 210 smokers of Regular cigarettes living in the continental United States. MAIN OUTCOME MEASURES: Percentage of respondents indicating knowledge of the presence of filter vents and the consequences of behavioural blocking of vents. RESULTS: Many smokers had not heard about or seen the filter holes: 43% (95% CI = 36 to 50%) of smokers of Ultra-lights, 39% (95% CI = 34 to 44%) of smokers of Lights, and 47% (95% CI = 40 to 54%) of smokers of Regulars. About two in three smokers either did not know of the existence of rings of small holes on the filters of some cigarettes, or did not know that blocking increases tar yields: 69% (95% CI = 63 to 75%) of Ultra- lights, 66% (95% CI = 61 to 71%) of Lights, and 69% (95% CI = 63 to 75%) of Regulars. CONCLUSIONS: Smokers are generally unaware of the presence and function of filter vents-a major design feature subject to behavioural blocking by smokers and now present on most cigarettes in the United States. Smokers and policy-makers need to be informed about the presence of filter vents and how vent blocking increases tar and nicotine yields from ostensibly very low-yield cigarettes.


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Ochratoxin A is a mycotoxin produced mainly by Penicillium verrucosum and Aspergillus ochraceus. Although typically considered a cereal contaminant, it has also been detected in dried fruit, nuts, meat and derivatives. To estimate the quantity of ochratoxin A that might be ingested by Italian consumers from these foods, 211 cereal derivatives (flours and bakery products) were analysed by high-performance liquid chromatography. Products were from conventional and organic agriculture and from integrated pest management agriculture. All commercial flours and derivatives examined contained ochratoxin A at concentrations very much below the legal limit (3 microg kg(-1)): the highest value, 0.816 microg kg(-1), was detected in a sample of spelt whole flour from organic agriculture. In many samples, the ochratoxin content was below the limit of detection; only rarely did values exceed 0.5 microg kg(-1). In baby foods, four samples were above the particularly restrictive Italian legal limit of 0.5 microg kg(-1). Although some significant differences were found between samples from conventional and organic agriculture when some product categories were examined (namely, baby foods as semolina and rice creams), no important difference was found between the two types of agricultural practice when all types of cereal derivatives were considered together.  相似文献   

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Concentrations of tin and lead in canned foods have been monitored since 1983 to determine the effects of recent changes in can-making technology. In the sample studied the proportion of foods contained in non-soldered as opposed to soldered cans has risen consistently during the survey and now accounts for 83% of all samples (excluding sardines). Foods contained in non-soldered cans have lower lead concentrations than those contained in soldered cans and this changeover is likely to result in a decrease in dietary lead intakes in the UK.  相似文献   

9.
Ready-to-eat foods at retail and catering establishments were randomly sampled at the point of sale for a period of 15 months. During this period, 4,469 food samples were examined for the presence of Campylobacter with the use of plate-based methodology. A range of different ready-to-eat food types, all of which have the potential to be contaminated with the organism, were examined. No viable Campylobacter cells were detected in any of the foods during the survey. There is no evidence that the foods examined in this study represent a risk to the consumer. Although these foods may be a vehicle for infection if cross-contamination occurs, other sources need to be investigated as causes of enteric infection caused by Campylobacter.  相似文献   

10.
介绍了目前国内外和广东省的宏观经济环境,对主要品种和原材料的产销形势进行了分析,对广东造纸市场的未来发展作了预测.  相似文献   

11.
The temporal trends of total mercury (THg) in four fish species in Lake Erie were evaluated based on 35 years of fish contaminant data. Our Bayesian statistical approach consists of three steps aiming to address different questions. First, we used the exponential and mixed-order decay models to assess the declining rates in four intensively sampled fish species, i.e., walleye (Stizostedion vitreum), yellow perch (Perca flavescens), smallmouth bass (Micropterus dolomieui), and white bass (Morone chrysops). Because the two models postulate monotonic decrease of the THg levels, we included first- and second-order random walk terms in our statistical formulations to accommodate nonmonotonic patterns in the data time series. Our analysis identified a recent increase in the THg concentrations, particularly after the mid-1990s. In the second step, we used double exponential models to quantify the relative magnitude of the THg trends depending on the type of data used (skinless-boneless fillet versus whole fish data) and the fish species examined. The observed THg concentrations were significantly higher in skinless boneless fillet than in whole fish portions, while the whole fish portions of walleye exhibited faster decline rates and slower rates of increase relative to the skinless boneless fillet data. Our analysis also shows lower decline rates and higher rates of increase in walleye relative to the other three fish species examined. The food web structural shifts induced by the invasive species (dreissenid mussels and round goby) may be associated with the recent THg trends in Lake Erie fish.  相似文献   

12.
ABSTRACT

This review describes the European Union and the US regulations applicable to food colours. Despite the different regulatory frameworks, the overall approach is similar, based on well-established risk-assessment procedures and risk-management measures. However, differences impacting free movement of goods can be found in the details and implementation of regulations. Using additives approved only in the US or in the EU implies that producers aiming to export need to adjust their product composition to the export market. Failure to comply may give rise to claims of adulteration, misbranding or non-compliance and rejection at the border or recall from the market. A careful comparison of the level of protection provided by the two sets of regulations, the criteria of good manufacturing practice (GMP) inspections and the certification requirements could be key to aligning the rules and to negotiating mutual recognition agreements. This review provides an extensive overview of the similarities and differences in regulating food colours in the EU and the US.  相似文献   

13.
This report presents data on the occurrence of aflatoxins (AF) and ochratoxin A in different types of flour marketed in Serbia. A total of 114 samples of wheat, buckwheat, rye, oat, barley, rice, millet and corn flour were collected in the period 2012–2016 and analysed using high performance liquid chromatography with fluorescence detection. Among flours other than corn, AFB1 was quantified only in rice, while ochratoxin A (OTA) was found in 29% of the samples. In corn flours the percentage of positive samples varied greatly over the years: AFB1 7.1–80.0%, OTA 30.0–40.6%, with a co-occurrence of 7.1–34.4%. Overall 5.2% of flours other than corn and 10.7% of corn flours exceeded the maximum levels (MLs) for AFB1 and/or OTA. The highest recorded levels were 8.80 μg kg?1 of AFB1 (corn) and 23.04 μg kg?1 of OTA (rye). Overall mean contamination levels of corn flours were 0.53 μg kg?1 of AFB1 and 0.46 μg kg?1 of OTA.  相似文献   

14.
探讨北京市房山区急性胃肠炎的流行病学特征和社会经济负担。方法 开展为期12个月的社区人群横断面调查,分析急性胃肠炎的发病情况、影响因素分布、临床表现、诊治情况以及经济负担。结果 2014年4月—2015年3月共调查1 678人,急性胃肠炎月患病率为0.65%(95%CI:0.27%~1.03%),年发病率为0.085次/人(95% CI:0.017~0.098次/人),每年房山区约有8.7万人次发生急性胃肠炎,食源性比例为54.5%(6/11)。发病时间主要集中在第二季度,低年龄段、文化程度较低、家庭收入较低、居住在农村的人群,急性胃肠炎患病风险较高。72.7%(8/11)的病例进行了药物治疗,54.5%(6/11)的病例去医疗机构就诊,药物治疗的病例中87.5%(7/8)使用抗生素,急性胃肠炎造成总经济损失约为0.32亿元,占2014年房山区地区生产总值(519.3亿元)的0.62‰。结论 房山区急性胃肠炎的疾病负担值得关注,且食源性比例较高,儿童患病风险较高,抗生素使用率较高,应加强食源性疾病监测和负担评估,探索有针对性的干预措施,为减轻食源性疾病的社会经济负担,提高防控能力提供科学依据。  相似文献   

15.
This paper presents data on the occurrence of Fusarium toxins – zearalenone (ZEA), deoxynivalenol (DON) and fumonisins (FUMs) B1 and B2 – in corn flours and corn flakes marketed in Serbia. A total of 71 samples were collected over 2013–2016 and analysed using HPLC with UV or fluorescence detection. In the case of corn flours, none of the samples taken in 2013 exhibited the presence of ZEA or DON, whereas 90% were positive for FUMs. In 2015, occurrence was very high: ZEA 93%, DON 86% and FUMs 100% (mean 43.3, 322.6 and 323.0 μg kg?1, respectively), with 21% of the samples exceeding the maximum level for ZEA and 7% for DON and FUMs. In 2016, a lower occurrence was recorded in the case of ZEA (75%) and DON (38%), with drastically lower mean contamination levels (six- and 10-fold, respectively), while FUMs stayed at 97%, with twofold lower mean. The maximum level was exceeded only for ZEA (3%). The frequency of ZEA–DON–FB1 co-occurrence was 86% in 2015 and 25% in 2016. Regarding corn flakes, occurrence summarised for the study period was 87% ZEA, 73% FUMs and 40% DON. One sample (7%) exceeded the maximum levels for both ZEA and DON. Observed occurrence changes were in agreement with the climatic conditions during corn growing seasons preceding the market release of the processed products.  相似文献   

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17.
Food Science and Biotechnology - Mangrove bioresources are considered as promising for bioprospecting due to rich biological diversity such as food, pharmaceutical, agricultural, and industrial...  相似文献   

18.
This research was conducted to determine the biogenic amine (BA) and ethyl carbamate (EC) concentrations in commercial Primitivo wine samples and the influence of the use of malolactic starter culture on concentrations of these potentially hazardous compounds in this wine. One hundred sixty bottles of wine from eight producers in the Apulia region of southern Italy were purchased at retail and analyzed. The most common BAs were histamine, 2-phenylethylamine, tyramine, cadaverine, putrescine, spermine, and spermidine. Putrescine (derived from ornithine) was the most abundant BA in all commercial Primitivo wines (5.41 to 9.51 mg/liter), 2-phenylethylamine was detected in only two commercial wines (at less than 2.12 mg/liter), and histamine was found at concentrations of 1.49 to 16.34 mg/liter. The concentration of EC in commercial Primitivo wine was 6.81 to 15.62 ppb, which is not considered dangerous for human health. Malolactic fermentation (MLF) affected the concentrations of BAs and EC differently. For EC, no significant differences were detected between samples of wine produced by spontaneous fermentation and wine that was inoculated malolactic starter. Mean EC concentrations were 12 and 14 ppb in two batches tested (always 18 ppb or less), regardless of whether the malolactic starter was added. Although present at trace levels in wine before the MLF, histamine accumulated during the MLF process, regardless of whether the malolactic starter was added. However, the increase in histamine was higher in wines without the malolactic starter. The concentrations of putrescine and cadaverine increased after MLF, especially in the wine that spontaneously fermented. The use of a selected malolactic starter resulted in reductions in BA concentrations in wine produced by this guided MLF compared with wine produced by spontaneous MLF.  相似文献   

19.
The METAALICUS (Mercury Experiment To Assess Atmospheric Loading In Canada and the US) project is a whole ecosystem experiment designed to study the activity, mobility, and availability of atmospherically deposited mercury. To investigate the dynamics of mercury newly deposited onto a terrestrial ecosystem, an enriched stable isotope of mercury (202Hg) was sprayed onto a Boreal forest subcatchment in an experiment that allowed us, for the first time, to monitor the fate of 'new' mercury in deposition and to distinguish it from native mercury historically stored in the ecosystem. Newly deposited mercury was more reactive than the native mercury with respect to volatilization and methylation pathways. Mobility through runoff was very low and strongly decreased with time because of a rapid equilibration with the large native pool of "bound" mercury. Over one season, only approximately 8% of the added 212Hg volatilized to the atmosphere and less than 1% appeared in runoff. Within a few months, approximately 66% of the applied 202Hg remained associated with above ground vegetation, with the rest being incorporated into soils. The fraction of 202Hg bound to vegetation was much higher than seen for native Hg (<5% vegetation), suggesting that atmospherically derived mercury enters the soil pool with a time delay, after plants senesce and decompose. The initial mobility of mercury received through small rain events or dry deposition decreased markedly in a relatively short time period, suggesting that mercury levels in terrestrial runoff may respond slowly to changes in mercury deposition rates.  相似文献   

20.
Although Fusarium species remain a main source of mycotoxin contamination of wheat, in recent years, due to the evident climatic changes, other mycotoxigenic fungi have been recognised as important wheat contaminants. Alternaria species, especially A. alternata, have been found as contaminants of wheat as well as wheat-based products. Under favourable conditions A. alternata very often produce alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA) and others Alternaria toxins. The aim of the present study was to examine the presence of three Alternaria toxins (AOH, AME and TeA) in wheat samples harvested during three years (2011–13). To this end, 92 samples were collected during wheat harvesting from different growing regions of the Autonomous Province of Vojvodina, which represents the most important wheat-growing area in Serbia. The presence of Alternaria toxins was analysed by HPLC with electrospray ionisation triple quadrupole mass spectrometry (LC-ESI-MS/MS). Among all the analysed wheat samples, 63 (68.5%) were contaminated with TeA, 11 (12.0%) with AOH and 6 (6.5%) with AME. Furthermore, the maximum and mean toxin concentrations were 2676 and 92.4 µg kg?1, 48.9 and 18.6 µg kg?1, and 70.2 and 39.0 µg kg?1 for TeA, AOH and AME, respectively. Co-occurrence of three Alternaria toxins in wheat samples was detected in six samples; a combination of two toxins was found in two samples; and 64 samples contained one toxin. The results showed that among 92 analysed wheat samples, only 20 (21.7%) samples were without Alternaria toxins. The presence of Alternaria toxins was also investigated in terms of weather conditions recorded during the period of investigation, as well as with the sampling region. This study represents the first preliminary report of the natural occurrence of Alternaria toxins in wheat (Triticum aestivum) from Serbia.  相似文献   

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