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Passive Smoking

Passive Smoking Report

Going smoke-free

The medical case for clean air in the home, at work and in public places

A report on passive smoking by the Tobacco Advisory Group of the Royal College of Physicians, July 2005

Tobacco smoke kills more people in the UK than any other avoidable cause. Therefore, effective tobacco control policies have a major part in improving public health. Since publishing the White Paper Smoking kills in 1998, the Government has made progress in many areas, particularly in developing smoking cessation services and banning the advertising and marketing of tobacco products. But much more can be done.

One important area is the harm caused by passive smoking. The 1998 White Paper recognised this and contained proposals for a voluntary code of practice to prevent passive smoke exposure in most workplaces, and a Public Places Charter to reduce exposure to smoke in pubs, restaurants and other hospitality industry venues. Although the voluntary code of practice was drafted it was not implemented, and the Public Places Charter has failed.

This report sets out in detail the impact of passive smoking in the UK. It reviews the effectiveness, and the ethical and economic implications of legislating to prevent exposure, and concludes that the only viable solution is legislation to make all workplaces and public places smoke-free. The Scottish Parliament has already decided on this approach.

The primary reason for smoke-free workplaces and public places is to protect individuals against involuntary exposure to passive smoking and the associated health risks. However, comprehensive smoke-free policies offer more than simple protection against passive smoke. Smoke-free policies help smokers to give up smoking, and discourage young people from starting to smoke in the first place. They also protect children at home by helping parents to quit, or at least by encouraging them to make their homes smoke-free. The particular benefit to children and other vulnerable or disadvantaged people in our society are important additional justifications for smoke-free legislation.

This report demonstrates how smoke-free legislation will save lives, reduce health inequalities, and improve public health. Smoke-free policies are popular and they are highly effective. Introducing comprehensive smoke-free legislation should be a public health priority for the UK.

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Tobacco Smoke Identified as Toxic Air Contaminant

State of California – technical report citing Tobacco Smoke as a Toxic Air Contaminant

Proposed Identification of Environmental Tobacco Smoke as a Toxic Air Contaminant

Download the full report on the Proposed Identification of Environmental Tobacco Smoke as a Toxic Air Contaminant here.

This report, prepared by the staff of the Air Resources Board (ARB), contains an evaluation of exposures to environmental tobacco smoke (ETS) in California. This report is referred to as Part A, “Proposed Identification of Environmental Tobacco Smoke as a Toxic Air Contaminant.” The Office of Environmental Health Hazard Assessment (OEHHA) has developed a comprehensive health evaluation on exposures to environmental tobacco smoke, referred to as Part B. Together, these evaluations serve as the basis for ARB’s proposal to identify ETS by regulation as a toxic air contaminant (TAC).

Under the provisions of Assembly Bill 1807 (Health and Safety Code sections 39650-39662), the ARB is mandated to administer California’s TAC Program. The ARB’s exposure assessment is based, to the extent available, upon research and monitoring data, emissions inventory data, and information on exposures from data on ambient and indoor air environments, as well as, an assessment of children’s exposures (Health and Safety Code Sections 39650 et seq.). The Health and Safety Code, section 39655, also requires that each candidate TAC must meet the definition of a TAC, defined as “an air pollutant which may cause or contribute to an increase in mortality or in serious illness, or which may pose a present or potential hazard to human health.”

ETS entered the identification program in June 2001. Some of the information in this report is based upon data presented in the Office of Environmental Health Hazard Assessment’s (OEHHA) 1997 report: “Health Effects of Exposure to Environmental Tobacco Smoke” (OEHHA, 1997). Specifically, Chapter 2 (Exposure Measurement and Prevalence) of the OEHHA report was updated to include ETS exposure information developed subsequent to the data presented in the report (after 1995). The National Cancer Institute (NCI), acting for the U.S. Public Health Service, recognized the importance of the 1997 OEHHA report and incorporated it as part of their Smoking and Tobacco Control Monograph series (NCI, 1999).

This is the revised Scientific Review Panel (SRP) version of the report which includes the Executive Summary, Part A (exposure assessment), Part B (health effects), and Part C (responses to public comments) documents. This version of the report, along with the comments received on the public review version, will be considered by the SRP on Toxic Air Contaminants at a noticed public meeting.

The ARB’s consideration of ETS as a TAC will occur following review by the SRP. If the SRP approves the report, it will be presented to the ARB at a duly noticed public hearing, after a 45-day public comment period. If the ARB approves the report at a hearing and identifies ETS as a TAC, the information contained in the report will be used in the assessment of the need for control measures. Any consideration of control measures to reduce exposures to ETS, if identified as a TAC, will follow a separate rulemaking process, which allows for a thorough public process including workshops, and a public hearing.

Mortality associated with passive smoking in Hong Kong

BMJ 2005;330:287-288 (5 February), doi:10.1136/bmj.38342.706748.47 (published 27 January 2005)

S M McGhee, associate professor1, S Y Ho, research assistant professor1, M Schooling, research associate1, L M Ho, senior computer manager1, G N Thomas, research assistant professor1, A J Hedley, chair professor1, K H Mak, consultant, community medicine2, R Peto, professor of medical statistics and epidemiology3, T H Lam, chair professor and head of department1

1 Department of Community Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong, China, 2 Department of Health, Student Health Service, 4/F Lam Tin Polyclinic, Kowloon, Hong Kong, China, 3 Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX2 6HE

Correspondence to: T H Lam


Passive smoking can cause death from lung cancer and coronary heart disease, but there is little evidence for associations with other causes of death in never smokers. A recent study showed increased all cause mortality with exposure to secondhand smoke at home but did not examine associations with specific causes of death and dose-response relations.1 We have published estimates of the mortality attributable to active smoking in Hong Kong2 and now present the related findings on passive smoking at home.

Participants, methods, and results

Details of the sample selection and data collection have been reported.2 Each person who reported a death in 1998 at four death registries was given a questionnaire which asked about the lifestyle 10 years earlier of the decedent and of a living person about the same age who was well known to the informant. Passive smoking was identified in the interview with the question, “Ten years ago, in about 1988, excluding the decedent/control, how many persons who lived with the decedent/control smoked?” Decedents or controls who lived with one or more smokers were classed as exposed. Cause of death was obtained from the death certificate.

We selected never smoking decedents and controls aged 60 years or over because there were few younger controls. To avoid selection bias, we included only cases and controls who had a living spouse at the time of reporting. We used logistic regression to derive odds ratios adjusted for age and education, and for sex when men and women were combined.

What is known on this topic

There is strong evidence that passive smoking is causally associated with death from lung cancer, coronary heart disease, and all causes, and also with acute stroke

What this study adds

The dose-response relation between passive smoking and mortality from stroke and chronic obstructive pulmonary disease, as well as from lung cancer, ischaemic heart disease, and all causes of death, strengthens the causal link

We identified 4838 never smoking cases (55% male) and 763 never smoking controls (55% male). All controls were used in the analysis for each specific cause of death.

We found significant dose dependent associations between passive smoking and mortality from lung cancer, chronic obstructive pulmonary disease, stroke, ischaemic heart disease, and from all cancers, all respiratory and circulatory diseases, and all causes (table). The association between mortality and passive smoking did not differ between males and females. Deaths due to injury or poisoning were not associated with passive smoking.

View this table:
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Number of subjects who were or were not exposed to secondhand smoke at home and odds ratios (adjusted for age and education, and for sex when men and women were combined) for mortality in people aged 60 or over, Hong Kong. Values are odds ratio (95% confidence interval) unless indicated otherwise


Dose dependent associations between passive smoking and causes of death are consistent with previous findings for lung cancer and coronary heart disease and extend the evidence on stroke. Previous studies have shown associations between passive smoking and first acute strokes,3 4 and we have now shown a dose-response relation with mortality from stroke. Previous studies focused on ischaemic strokes but Chinese populations have a greater incidence of haemorrhagic stroke than do white populations,5 implying that many of the strokes in our study may have been non-ischaemic. Passive smoking probably affects all stroke subtypes, as does active smoking.

Our finding of a 34% increase in all cause mortality is consistent with but higher than that (15%) in the New Zealand cohort.1 Exposure to secondhand smoke at home is higher in Hong Kong than in New Zealand due to crowded living conditions. Before the 1990s, awareness of the danger of passive smoking was lower and smokers smoked freely at home.

We focused on passive smoking at home because the proxy reporter could most reliably supply these data, and we adjusted for education, which was also reliably recorded2 and is a good proxy for social class in Hong Kong. As data on cases and controls were derived from the same proxy, reporting bias should be minimal.2 If our results are not due to residual confounding, they provide further evidence that the dose-response associations between passive smoking and stroke and all cause mortality are likely to be causal.

See Editorial by Kawachi

This article was posted on on 27 January 2005:

We thank W L Cheung for help with analysis; the Immigration Department of the Government of the Hong Kong Special Administrative Region for data and assistance; and, in particular, the relatives who provided information.

Contributors: THL, SYH, AJH, KHM, and RP designed and carried out the study on which this analysis was based; SMcG, MS, LMH, and GNT planned and carried out this analysis; and all authors contributed to writing the paper. SMcG and THL are guarantors.

Funding: Hong Kong Health Services Research Committee (#631012) and Hong Kong Council on Smoking and Health.

Competing interests: THL is vice chairman and AJH a former chairman of the Hong Kong Council on Smoking and Health.

Ethical approval: Ethics Committee of the Faculty of Medicine, University of Hong Kong.

1. Hill SE, Blakely TA, Kawachi I, Woodward A. Mortality among never smokers living with smokers: two cohort studies, 1981-4 and 1996-9. BMJ 2004;328: 988-9.[Free Full Text]
2. Lam TH, Ho SY, Hedley AJ, Mak KH, Peto R. Mortality and smoking in Hong Kong: case-control study of all adult deaths in 1998. BMJ 2001;323: 361-2.[Abstract/Free Full Text]
3. Bonita R, Duncan J, Truelson T, Jackson RT, Beaglehole R. Passive smoking as well as active smoking increases the risk of acute stroke. Tobacco Control 1999;8: 156-60.[Abstract/Free Full Text]
4. Iribarren C, Darbinian J, Klatsky AL, Friedman GD. Cohort study of exposure to environmental tobacco smoke and risk of first ischemic stroke and transient ischemic attack. Neuroepidemiology 2004;23: 38-44.[CrossRef][ISI][Medline]
5. Kay R, Woo J, Kreel L, Wong HY, Teoh R, Nicholls MG. Stroke subtypes among Chinese living in Hong Kong: the Shatin stroke registry. Neurology 1992;42: 985-7.[Abstract/Free Full Text]

(Accepted 12 August 2004)

Secondhand Smoke Exposure

Secondhand Smoke Exposure

S.M. McGhee, A.J. Hedley
Department of Community Medicine, University of Hong Kong, Hong Kong SAR, China

The smoke from a burning cigarette contains a toxic mix of chemical substances and the IARC has classed secondhand tobacco smoke (SHS) as a Group 1 carcinogen. The evidence of harm to adult passive smokers is mounting including lung cancer and respiratory illness, heart disease and stroke as well as more minor acute respiratory symptoms and irritation. Children are even more vulnerable with domestic exposures before and/or after birth resulting in low weight infants, chronic health problems and more frequent hospital admissions for respiratory disease. There is also evidence of damage to lipoproteins in children although much of the longer term harm has not yet been assessed.

For adults, the workplace has been a common site of exposure but, in many countries, smoke-free workplaces are becoming more common. In the developing world however, SHS remains as occupational hazard, In Hong Kong, non-smoking catering workers had urine cotinine levels which indicated a 3% increased risk of mortality from heart disease or lung cancer compared with a level of 0.1% for the US occupational health significant risk level.

Policy-makers everywhere need to protect non-smokers from this serious threat to their respiratory and cardiovascular health and thus protect their communities from serious economic loss.

Secondhand Smoke Does Cause Respiratory Disease

The report following report by Enstrom and Kabat confirms that exposure to secondhand smoke causes injury to the respiratory system with the finding of a combined increased mortality risk for men and women for chronic obstructive pulmonary disease.

Why Workplaces Should Be Smokefree

Published by ash June 2003:

Why Workplaces Should Be Smokefree 

Reasons why

  • There is now incontrovertible evidence that secondhand smoke is a killer – at least 1,000 people die from secondhand smoke exposure each year in the UK 1.
  • Some three million people 2 are still exposed to secondhand smoke in the workplace yet have little protection in law. Policies that aim to protect employees from tobacco smoke will also improve conditions for consumers.
  • Expert advice by the World Health Organisation states that ventilation is not effective in protecting people from secondhand smoke as there is no safe level of exposure below which there are no adverse effects.3
  • Public opinion supports smokefree workplaces – 78 per cent of the population 4 now believe that all employees should be able to work in a smokefree environment.
  • 80 per cent of the population don’t smoke 5. If smokers make an informed decision to smoke then that’s their decision – but it should not be allowed to impact on other people’s health.
  • 70 per cent of smokers would like to quit 6 and most believe smoke-free environments would help them in their quit attempts.
  • The UK is lagging a long way behind many other countries in protecting non smokers from secondhand smoke 7.

Health Arguments

  • Tobacco smoke is a potent cocktail of over 4,000 chemicals, including more than 50 known to cause cancer such as benzene and arsenic 8.
  • Secondhand smoke exposure (equivalent to just 1 percent of that of active smoking) carries a risk of coronary heart disease of almost half that of smoking 20 cigarettes a day 5.
  • People with particular illnesses are vulnerable to secondhand smoke, and they represent a substantial proportion of the population. For example there are 5.1 million people with asthma and 3 million with other types of lung disease, 2.1 million people with angina and 1.3 million people who have had a heart attack 5.
  • Secondhand smoke is a major trigger of asthma attacks and worsens respiratory conditions like bronchitis 5.
  • Exposure to secondhand smoke during pregnancy is linked to low birthweight and prematurity 9.
  • The health of workers improves immediately when smoking is banned in the workplace 10.

Economic Arguments

  • Smokefree policies cost less to put in place and enforce than policies allowing smoking 11.
  • Insurance, cleaning and maintenance costs are significantly reduced in smokefree workplaces 12.
  • Smokefree policies reduce smoking by employees, and are a cost-effective way of helping people quit smoking 13.
  • Less smoking means less absenteeism, lower worker turnover and fewer accidents 14 15 16.
  • Worldwide smokefree policies have been shown to have a positive or neutral impact on trade in bars and restaurants. The only studies showing a negative economic impact had tobacco industry backing and most were subjective and of poor quality 17.


  1. BMA Towards smoke-free workplaces, Board of Science and Education & Tobacco Control Resource Centre November 2002
  2. Survey source: MORI March 1999 Sample size:1,029 respondents
  3. WHO policies to reduce exposure to environmental tobacco smoke 29-30 May 2000
  4. Survey source: MORI Fieldwork dates: 20th – 24th March, 2003 Sample size: 1972 respondents
  5. BMA Towards smoke-free workplaces, Board of Science and Education & Tobacco Control Resource Centre November 2002
  6. Smoking related Behaviour & Attitudes Series OS no.18 June 2002
  7. See ASH website for up to date information at
  8. WHO International Agency for Research on Cancer (1986) Monograph vol.38 Tobacco Smoke. WHO IARC:Lyons.
  9. Windham GC, Hopkins B, Fenster L, & Swan SH (2000) Pre-natal active or passive tobacco smoke exposure and the risk of pre-term delivery or low birthweight. Epidemiology 11:427-33
  10. Eisner M, Smith A, Blanc P Bartenders respiratory health after establishment of Smoke-free Bars and Taverns JAMA 1998; 280 1909-1914
  11. Ducatman A,McLellan R. Epidemiological basis for an occupational and environmental policy on environmental tobacco smoke, Amer. Coll. of Occup. And Environmental Medicine, 2000
  12. Parrott S. Godfrey C. Cost of employee smoking in the workplace in Scotland. Tob. Control 2000:9(2):187-192
  13. Fichtenberg CM,Glantz SA Effect of smoke-free workplaces on smoking behaviour: systematic review. BMJ 2002;325:188-191
  14. McGhee S, Adab P, Hedley A, et al. Passive smoking at work: the short term cost. J.Epidemiol Community Health 2000; 54(9): 673-6
  15. Ryan J,Zwerling C,Jones M Cigarette smoking at time of hire as a predictor of employment outcome J.Occup Environ Medicine 1996;38(9):928-33
  16. Ryan J, Zwerling C, Orav E Occupational risks associated with cigarette smoking: a prospective study. Am J Public Health 1992; 82(1):29-32
  17. Scollo M et al Review of the quality of studies on the economic effects of smoke-free policies on the hospitality industry. Tobacco Control 2002; 12: 13-20

Further information

Clear the Air Coalition Statement:
More Clear the Air Campaign factsheets:
For detailed informaion visit ASH smokefree environments page:

Passive smoking at work

Department of Community Medicine, University of Hong Kong, 7 Sassoon Road, Pokfulam, Hong Kong

Correspondence to: Dr McGhee (

Accepted for publication 4 May 2000

STUDY OBJECTIVE: To estimate the impact of passive smoking at work on use of health care services and absenteeism.
DESIGN: Cross sectional survey.
SETTING: A workforce in Hong Kong.
PARTICIPANTS: 5142 never-smoking police officers in a total sample of 9926.

MAIN RESULTS: A consistently strong association was found among men between length of time exposed to passive smoking at work and self reported consultations with a doctor, use of medicines and time off work. Results for women were similar but most were not statistically significant.

CONCLUSIONS: The exposure of healthy adults to passive smoking at work is related to utilisation of health care services and extra time off work. This results in costs to the health services, to employers and to those exposed.

Environmental Tobacco Smoke Exposure and Ischaemic Heart Disease

Epidemiological studies have shown that the risk of ischaemic heart disease is about 30% greater in non-smokers who live with smokers than in those who do not. It seems implausible that the effect of environmental exposure to tobacco smoke should be so large when the excess risk associated with smoking 20 cigarettes per day is only about 80% at age 65 (the average age of ischaemic heart disease events in the studies). Environmental exposure to tobacco smoke is only about 1% that of smoking; the risk is nearly half. This paper on “Environmental tobacco smoke exposure and ischaemic heart disease” examines the possible explanations for this surprisingly large association.

Passive Smoking At Work A Risk Factor For Coronary Heart Disease

The following study was carried out in China to discover whether passive smoking at work is a risk factor for coronary heart disease. Of course, the results also apply to any other country where smoking at work can risk the health of non-smoking workers.


The conclusion was that passive smoking at work is a risk factor for coronary heart disease. Urgent public health measures are needed to reduce smoking and to protect non-smokers from passive smoking in China.