Secondhand smoke levels in Scottish pubs: the effect of smoke-free legislation

Objective

To compare levels of particulate matter, as a marker of secondhand smoke (SHS) levels, in pubs before and 2 months after the implementation of Scottish legislation to prohibit smoking in substantially enclosed public places.

Design

Comparison of SHS levels before and after the legislation in a random selection of 41 pubs in 2 Scottish cities.

Methods

Fine particulate matter <2.5 μm in diameter (PM_2.5) was measured discreetly for 30 min in each bar on 1 or 2 visits in the 8 weeks preceding the starting date of the Smoking, Health and Social Care (Scotland) Act 2005 and then again 2 months after the ban. Repeat visits were undertaken on the same day of the week and at approximately the same time of the day.

Results

PM_2.5 levels before the introduction of the legislation averaged 246 μg/m³ (range 8–902 μg/m³). The average level reduced to 20 μg/m³ (range 6–104 μg/m³) in the period after the ban. Levels of SHS were reduced in all 53 post‐ban visits, with the average reduction being 86% (range 12–99%). PM_2.5 concentrations in most pubs post‐ban were comparable to the outside ambient air PM_2.5 level.

Conclusions

This study has produced the largest dataset of pre‐ and post‐ban SHS levels in pubs of all worldwide smoke‐free legislations introduced to date. Our results show that compliance with the Smoking, Health and Social Care (Scotland) Act 2005 has been high and this has led to a marked reduction in SHS concentrations in Scottish pubs, thereby reducing both the occupational exposure of workers in the hospitality sector and that of non‐smoking patrons.Public health policy in a growing number of countries has moved to control non‐smokers'' exposure to secondhand smoke (SHS), with recent legislation introduced in Ireland, Italy, Spain and Norway. The Smoking, Health and Social Care (Scotland) Act 2005 to ban smoking in substantially enclosed public places was implemented on 26 March 2006 with the aim of protecting non‐smokers from the health effects of SHS.¹A recent review of occupational exposure to SHS suggested that workers in the hospitality sector have among the highest exposures to SHS of all occupational groups.² Data on exposure to SHS across a wide range of entertainment establishments indicated that airborne nicotine concentrations were up to 18.5 times higher than in offices or domestic residences.³ Studies have shown that non‐smoking bar workers have salivary cotinine levels four times those of non‐smokers who live with partners who smoke.⁴ Data from New Zealand indicate that non‐smoking hospitality workers in establishments that permit smoking have salivary cotinine levels between 3 and 4 times those of non‐smoking workers in smoke‐free premises.⁵ One estimate indicates that between 1500 and 2000 non‐smokers'' deaths per year in Scotland can be attributed to SHS exposure.⁶ It has been suggested that SHS exposure may lead to the deaths of over 50 hospitality sector workers in the UK each year.⁷The introduction of smoke‐free legislation in other countries has been shown to dramatically reduce SHS levels. A recent analysis of the effect of the Norwegian legislation⁸ showed that total dust levels in 13 bars and restaurants reduced from an average level of 262 to 77 μg/m³, a 70% reduction, whereas a study in the USA indicated that respirable dust levels in a selection of 8 hospitality venues reduced to approximately 9% of the pre‐ban level.⁹ Similar work in New York State in a mixture of bars and restaurants measured levels of particulate matter <2.5 μm in diameter (PM_2.5), and found that mean levels decreased from 412 to 27 μg/m³ (93.5%).¹⁰ Mulcahy et al¹¹ measured changes in airborne nicotine levels as a result of the Irish smoking ban. Their study of 20 pubs showed nicotine reductions of approximately 83%.Although there are currently no air quality standards for PM_2.5 in the UK, both the US Environmental Protection Agency (EPA) and the World Health Organization (WHO) have issued air quality guidance for outdoor air pollution levels measured in PM_2.5.^12,13 The US EPA air quality guidance is divided into bands, and for PM_2.5 these bands are arranged at cut points of <15.4 μg/m³ (good), 15.5–40.4 μg/m³ (moderate), 40.5–65.4 μg/m³ (unhealthy for sensitive groups), 65.5–150.4 μg/m³ (unhealthy), 150.5–250.4 μg/m³ (very unhealthy) and >250.5 μg/m³ (hazardous). The US EPA standard for PM_2.5 has a 24 h averaged target of 65 μg/m³, with an annualised average of 15 μg/m³. The WHO recently revised its outdoor air quality guidance and now recommends a 24 h average limit of 25 μg/m^3, with an annual average not exceeding 10 μg/m³ measured in PM_2.5.¹³This paper describes our methods of measurement of SHS concentrations in a selection of Scottish pubs and examines the changes in SHS levels that occurred as a result of the implementation of the ban on 26 March 2006. It forms part of a comprehensive evaluation strategy to measure the effects of the introduction of the Scottish smoke‐free legislation.¹⁴     

Wurtzite InP/InAs/InP core-shell nanowires emitting at telecommunication wavelengths on Si substrate

Optical properties of wurtzite InP/InAs/InP core-shell nanowires grown on silicon substrates by solid source molecular beam epitaxy are studied by means of photoluminescence and microphotoluminescence. The growth conditions were optimized to obtain purely wurtzite radial quantum wells emitting in the telecom bands with a radiative lifetime in the 5-7 ns range at 14 K. Optical studies on single nanowires reveal that the polarization is mainly parallel to the growth direction. A 20-fold reduction of the photoluminescence intensity is observed between 14 and 300 K confirming the very good quality of the nanowires.     

Powdered barley sprouts: composition,functionality and polyphenol digestibility

This study was performed to evaluate the phytochemical composition, in vitro antioxidant capacity, antihyperglycaemic and anti‐inflammatory activities, and simulated gastrointestinal digestion of 7‐day‐old freeze‐dried barley sprouts (BS), one hybrid and one nonhybrid variety: ‘NS565’ (BSNS) and ‘Golozrni’ (BSG), respectively. BSNS expressed significantly higher (P ≤ 0.05) content of total phenols, chlorophyll and carotenoids. Phenolic compounds were the most dominant bioactives in both BSNS and BSG (713.25 and 479.02 mg GAE 100 g^?1 DW, respectively). BSNS possessed significantly higher (P ≤ 0.05) antioxidant capacity, evaluated by DPPH and ABTS assays, and reducing power ( = 0.54 mg mL^?1; IC₅₀^ABTS = 0.79 mg mL^?1; RP_0.5 = 9.35 mg mL^?1). Antihyperglycaemic and anti‐inflammatory activities of BSNS ( = 1.43 mg mL^?1;  = 1.86 mg mL^?1) were also significantly higher (P ≤ 0.05) than BSG ( = 1.97 mg mL^?1;  = 4.40 mg mL^?1). In vitro simulation of gastrointestinal digestion showed higher release of phenolic compounds in intestinal fluid than in gastric fluid.     

Evaluation of a stage-specific proteolytic enzyme of Schistosoma mansoni as a marker of exposure

Cercarial elastase (CE) is one of the first proteins released in the host by invading schistosome cercariae. An enzyme-linked immunosorbent assay (ELISA)-formatted immunoassay has been developed to detect antibodies to the stage-specific CE antigen of Schistosoma mansoni as marker of exposure. We have evaluated this test system as an epidemiologic tool, using well-characterized sera collected from S. mansoni- and S. haematobium-infected subjects residing in endemic areas and from control subjects living in nonendemic areas in Egypt. Urine, stool specimens, and blood samples were collected from a sample of 272 endemic subjects randomly selected to represent different age groups in the range of 2-20 years of age. Of 47 S. mansoni-infected subjects, 41 (87.2%) had anti-CE IgG antibodies. Of 52 S. haematobium-infected cases, 38 (73.0%) had IgM antibodies to CE and 43 (82.7%) had IgG antibodies to CE. Of 173 egg-negative people in the endemic area, 84 (48.6%) were IgM positive and 99 (57.2%) were IgG positive. The mean IgM and IgG antibody levels were similar in the infected groups but were significantly lower in the egg-negative group (P = 0.001). All sera from young children (2-3 years of age) were uniformly ELISA negative. The prevalence of IgM and IgG antibodies to CE in children less than six years of age were significantly lower than in other age groups. There was no significant difference in prevalence rates of IgM and IgG anti-CE antibodies between subjects having other parasites present in the endemic area (Ascaris lumbricoides, Entrobius vermicularis, Hymenolepis nana, H. diminuta, Trichostrongylus spp., and Entamoeba histolytica) and those without any parasitic infection. All nonendemic sera (58), including those with other helminth infections, were uniformly ELISA negative for antibodies to CE. These findings suggest that antibodies to elastase indicate exposure, but not necessarily active schistosome infection.     

Chemical reactor network modeling of a microwave plasma thermal decomposition of H2S into hydrogen and sulfur

The conventional treatment method for H₂S is the Claus process, which produces sulfur and water. This results in a loss of the valuable potential product hydrogen. H₂S treatment would be more economically valuable if both hydrogen and sulfur products could be recovered. Based on standard heats of formation analysis, the theoretical energy required to produce hydrogen from H₂S dissociation is only 20.6 kJ/mol of H₂ as compared to 63.2 kJ/mol of H₂ from steam methane reforming and 285.8 kJ/mol of H₂ from water electrolysis. Among the many thermal decomposition methods that have been explored in the literature, Micro-wave plasma dissociation of H₂S prevails as the method of choice to attain the best conversion and energy efficiency. Chemical kinetics simulations using an ideal flow reactor network have been carried out on the CHEMKIN-PRO software package and they support these findings. The reactor network simulates the thermal plasma behavior in the plasma torch, the plasma reactor, and the sulfur condenser. Two chemical kinetics mechanisms have been used and the results show an almost complete conversion of H₂S into hydrogen and sulfur in the plasma reactor at an optimum temperature of about 2400 K at atmospheric pressure. While the most challenging task of the process is found to be the plasma cooling rate at the sulfur condenser where very fast quenching is required to conserve the hydrogen product from converting back to H₂S.     

Effect of sintering temperature on the microstructures and mechanical properties of sodalite infiltrate all-ceramic material for dental restorations

ABSTRACT

Potassium bromide sodalite (KBr-SOD) zeolite has been developed to enhance the mechanical properties of these restorations using a direct in situ hydrothermal condition followed by the sintering process. The purpose of this study was to determine the effects of sintering temperature on the microstructures and mechanical properties of porous alumina (A) and zirconia-toughened alumina (ZTA) discs infiltrated by KBr-SOD. Hundred and twenty disc-shaped samples were sintered at various temperatures and prepared for biaxial flexural strength and Vickers microhardness tests. The results showed that sintering temperatures from 1100 to 1600°C for both A-SOD and ZTA-SOD samples has resulted in a significant improvement in the density (2.8 and 1.1%, respectively), flexural strength (257 and 254%, respectively), Vickers hardness (109 and 112%, respectively), and Weibull modulus (7.5 and 3%, respectively). The present study concludes that infiltrated SOD material sintered at 1600°C is suitable for the fabrication of all-ceramic dental prostheses with adequate mechanical properties.     

Recent developments in biochar as an effective tool for agricultural soil management: a review

In recent years biochar has been demonstrated to be a useful amendment to sequester carbon and reduce greenhouse gas emission from the soil to the atmosphere. Hence it can help to mitigate global environment change. Some studies have shown that biochar addition to agricultural soils increases crop production. The mechanisms involved are: increased soil aeration and water‐holding capacity, enhanced microbial activity and plant nutrient status in soil, and alteration of some important soil chemical properties. This review provides an in‐depth consideration of the production, characterization and agricultural use of different biochars. Biochar is a complex organic material and its characteristics vary with production conditions and the feedstock used. The agronomic benefits of biochar solely depend upon the use of particular types of biochar with proper field application rate under appropriate soil types and conditions. © 2016 Society of Chemical Industry     

A Comparative Study of the Effectiveness of Adaptive Filter Algorithms,Spectral Kurtosis and Linear Prediction in Detection of a Naturally Degraded Bearing in a Gearbox

Diagnosing bearing faults at the earliest stages is critical in avoiding future catastrophic failures. Many techniques have been developed and applied in diagnosing bearings faults; however, these traditional diagnostic techniques are not always successful when the bearing fault occurs in gearboxes where the vibration response is complex; under such circumstances, it may be necessary to separate the bearing signal from the complex signal. In this paper, an adaptive filter has been applied for the purpose of bearing signal separation. Four algorithms were compared to assess their effectiveness in diagnosing a bearing defect in a gearbox, least mean square (LMS), linear prediction, spectral kurtosis and fast block LMS. These algorithms were applied to decompose the measured vibration signal into deterministic and random parts with the latter containing the bearing signal. These techniques were applied to identify a bearing fault in a gearbox employed for an aircraft control system for which endurance tests were performed. The results show that the LMS algorithm is capable of detecting the bearing fault earlier in comparison with the other algorithms.