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New Zealand Respiratory Conference 2014. Asbestos and Public Health in Canterbury Dr. Alistair Humphrey, with thanks to Professor Bill Glass Medical Officer of Health for Canterbury, New Zealand Ministry of Health [2]. What is asbestos?. A naturally occurring mineral in different forms:
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New Zealand Respiratory Conference 2014 Asbestos and Public Health in Canterbury Dr. Alistair Humphrey, with thanks to Professor Bill Glass Medical Officer of Health for Canterbury, New Zealand Ministry of Health [2]
What is asbestos? • A naturally occurring mineral in different forms: • Heat resistant • Light and binds cement • Abundant and cheap • Found mainly in • Canada • Russia • South Africa • Australia Philip Noble and Ross Munroe, Wittenoom, 1953
Chrysotile (white) • Is Magnesium silicate, white in colour. • The magnesium which is in the outer layer of the fibre can leach out in the lung tissue fluids when inhaled leading to a breakdown in the fibre and its digestion by macrophages (lung scavenger cells). • These cells can be coughed up, so reducing the body burden. • However, if the exposure or “dose” of the inhaled fibres is too great, the protective macrophage response may be overwhelmed and lung disease develop.
Amosite (brown) • Is iron-magnesium silicate. • Grey-brown in colour. • The fibres are long, straight, resistant to lung tissue fluids, and can survive unchanged in the body for years.
Crocidolite (blue) • Is an iron-sodium silicate. • Blue in colour. • The fibres are straight and rigid. They can split longitudinally producing fine fibrils. • Their outer lining makes them resistant to lung tissue fluids so that they can survive unchanged in the lungs for 40 years or more and migrate to the lung lining (pleura).
Relative sizes of fibres • Asbestos 0.1 – 10μm • Bacteria 0.2- 12μm • Silk 5-10μm • Merino wool 10-15μm • Human hair 20-100μm μm
Where is asbestos used? • Asbestos cement products • Roofing • Cladding • Pipes • Insulation • Boilers • Pipes • Steel • Brake lining • Lino backing • Decorative ceiling • Asbestos cement products • Roofing • Cladding • Pipes • Insulation • Boilers • Pipes • Steel • Brake lining • Lino backing • Decorative ceiling
Who are exposed? • Construction workers • Brake lining repairers • Asbestos cement manufacturing workers • Fitters • Boilermen • Plumbers • Electricians • Ships engineers • Customs inspectors(rummagers) • Bulk handlers such as waterside workers • Asbestos removal workers • Demolition workers, • Lino layers • Home renovators
Secondary exposure • Where clothes covered in dust are taken home by workers • Where wives/daughters wash asbestos covered clothes regularly • Where asbestos dust is not cleaned up properly in a residence or workplace
How is asbestos a health risk? • The size of the particles (<10 μm) • Its persistent in the lung tissue • Its latency • The dose • The period of time someone is exposed • How often they are exposed during that time • The concentration of asbestos dust during their exposures
Pleural plaques • Changes in the linings of the lungs – the pleura – leading to thickening, or discrete nodular lesions called plaques • While these conditions indicate tissue damage, they are not normally associated with impairment of lung function or the presence of symptoms
Asbestosis • This is a response by the lung tissue to the inhalation of asbestos fibres • In its pure manifestation scarring of the lung tissue develops over time, the lungs shrink as a result, lung function is impaired with increasing shortness of breath
Lung Cancer (SCC) • Cancer resulting from exposure to asbestos fibres does not differ from lung cancer due to cigarette smoke • In the past many asbestos workers also smoked so that attribution for the cause of the lung cancer was not clear
Mesothelioma • This is a rapidly developing form of cancer which occurs to the lining of the lungs. • There is no evidence to date that it develops on the basis of pre-existing pleural plaques
NZ Public Health & Disability Act 2000 - Asbestos • General component (Objectives of DHBs) 22(1) Every DHB has the following objectives: To improve, promote and protect the health of people and communities. • Specific component (Functions of DHBs) 23(h) To promote the reduction of adverse social and environmental effects on the health of people and communities.
Health & Safety in Employment Act 1992 5 Object of Act The object of this Act is to promote the prevention of harm to all persons at work and other persons in, or in the vicinity of, a place of work 7 Identification of hazards (1) Every employer shall ensure that there are in place effective methods for— (a) systematically identifying existing hazards (b) systematically identifying (if possible before, and otherwise as they arise) new hazards 8 Significant hazards to employees to be eliminated if practicable Where there is a significant hazard, the employer shall take all practicable steps to eliminate it.
JOEM • Volume 47, Number 8, August 2005 Risk Assessment for Asbestos-RelatedCancer From the 9/11 Attack on the World Trade Center Robert P. Nolan, PhD Malcolm Ross, PhD Gordon L. Nord, PhD Charles W. Axten, PhD Jeffrey P. Osleeb, PhD Stanislav G. Domnin, MD, DSc Bertram Price, PhD Richard Wilson, DPhil
Negligible risk Results: The upper limit for the expected number of asbestos-related cancers is less than one case over the lifetime of the population NYC 9/11 – Peak of 50f/ml ChCh 22/2 - Peak of 1f/ml 50m from sites
Asbestos inside buildings • CDHB Board raised concerns in May 2012 about asbestos in houses during earthquake repairs • CPH met with EQC in August 2012 and asked for: • A moratorium on encasement • A through risk assessment of the process • Despite repeated requests EQC did not meet with CDHB • In January 2013 “The Press” ran a story on asbestos risk
EQC response to media questions January 2012 What is EQC’s policy on the encasement of damaged asbestos ceilings in homes? • “We have had a working group develop the EQC asbestos policy.” • “The group was chaired by an independent health and safety consultant.” • “Enclosing is one of the repair strategies available, the other being removal. In about 90 percent of cases where asbestos is found, it is removed.” • “Our repair strategies are in line with Ministry of Business, Innovation and Employment guidelines.”
Questions for EQC • Was a risk assessment carried out before developing these guidelines? • (as recommended Ministry of Health’s Guidelines) • Who was EQC’s H&S “expert” ? • How many ceilings had been encased ? • Of 43,500 homes, 10% (4000) were damaged, 800 with asbestos damage, 297 with asbestos ceilings , about 30 of which were encased – Jan 2013 • EQC then said 47% of all homes tested were positive 5060 requested tests – May 2013 • Where were these properties? • EQC first said they wouldn’t say, then said they couldn’t say • Was work being carried out by “person with a certificate of competence”? • For removal – yes • For encapsulation/sealing – yes • For encasement - no
Asbestos Review Panel March ‘92 – July 2012 1299 Cases Notified 232 cases of mesothelioma 124 cases of lung cancer 294 cases of asbestosis 649 cases of pleural abnormalities • Asbestos Processors 7.5% • Asbestos Sprayers 4.5% • Carpenters/Builders 25% • Electricians 7.5% • Friction Products 1% • Other 9% • Plumbers, Laggers etc 37% • Watersiders 6.5% • No Known Exposure 1% • Non-Occupational 1%
home renovators and innocent bystanders are now presenting with asbestos-related diseases and dying from mesothelioma. In the course of our investigations we heard from experts that even though, historically, it was the workers in the asbestos industries who had contracted asbestos related diseases, several additional waves are now occurring. Tradesmen, home renovators and innocent bystanders are now presenting with asbestos-related diseases and dying from mesothelioma. In some cases, those deaths have resulted from minimal contact with asbestos which occurred years before the diagnosis. For example, a woman in South Australia developed mesothelioma in her early thirties from an exposure that occurred as a child while playing near bonded asbestos being worked on by her father*. There are many similar stories about people dying from non-occupational exposure to asbestos in circumstances which were previously thought to be harmless. * Amaca Pty Ltd v CSR Limited [2008] NSW DDT 18
Med J Aust. 2011 Sep 5;195(5):271-4. Increasing incidence of malignant mesothelioma after exposure to asbestos during home maintenance and renovation. Olsen NJ, Franklin PJ, Reid A, de Klerk NH, Threlfall TJ, Shilkin K, Musk B. Source University of Western Australia, Perth, WA, Australia. nola.olsen@uwa.edu.au Abstract OBJECTIVE: To determine trends in incidence of malignant mesothelioma (MM) caused by exposure to asbestos during home maintenance and renovation. DESIGN, SETTING AND PARTICIPANTS: Using the Western Australian Mesothelioma Register, we reviewed all cases of MM diagnosed in WA from 1960 to the end of 2008, and determined the primary source of exposure to asbestos. Categories of exposure were collapsed into seven groups: asbestos miners and millers from Wittenoom; all other asbestos workers; residents from Wittenoom; home maintenance/renovators; other people exposed but not through their occupation; and people with unknown asbestos exposure; or no known asbestos exposure. Latency periods and age at diagnosis for each group were calculated and compared. RESULTS: In WA, 1631 people (1408 men, 223 women) were diagnosed with MM between 1960 and 2008. Since 1981, there have been 87 cases (55 in men) of MM attributed to asbestos exposure during home maintenance and renovation, and an increasing trend in such cases, in both men and women. In the last 4 years of the study (2005-2008), home renovators accounted for 8.4% of all men and 35.7% of all women diagnosed with MM. After controlling for sex and both year and age at diagnosis, the latency period for people exposed to asbestos during home renovation was significantly shorter than that for all other exposure groups, but the shorter follow-up and difficulty recalling when exposure first occurred in this group may partly explain this. CONCLUSIONS: MM after exposure to asbestos during home renovation is an increasing problem in WA, and these cases seem to have a shorter latency period than other types of exposure. MM cases related to renovation will probably continue to increase because of the many homes that have contained, and still contain, asbestos building products
The management of asbestos in the non-occupational environment Ministry of Health May 2013 Public health risks from non-occupational exposure to asbestos-containing materials in earthquake damaged Christchurch homes • It is reasonable to conclude that very low level domestic asbestos exposure can result in health effects. • The risk to residents is likely to be small if: • the asbestos is chrysotile, • the concentration of asbestos in the material is low • maximum duration of exposure is in the order of hours rather than days or longer.
Asbestos issue: • Fletcher EQR estimated that about 35,000 homes were repaired without a proper risk assessment • That about 9000 homes would have had some asbestos work done (without any precautions) • A very small proportion of these would have had any significant contamination
Was due process followed? • Investigation by Worksafe ongoing • Canterbury established a workgroup to deal with potential public anxiety: • Worksafe • Fletcher EQR • Canterbury DHB • Ministry of Health • ECAN communications (expertise in hazardous substances) • Occupational Health experts
Plan for dealing with public anxiety • A retrospective risk assessment process to be developed by Fletcher EQR by May 29th • The most heavily contaminate homes to be tested by Fletcher EQR • Tests to independently validated and publicised by health agency (having independent credibility)
Wellington takes over • Worksafe removed from process by a higher power • Fletcher EQR removed three days later • High level meeting convened which establishes DPMC as the lead agency: • Monitoring the media (Interagency comms in Chch banned) • Establishing an asbestos “technical advisory group” • Health is in the process of producing a “reassuring” Q&A
What is happening now? • Tradesmen are now calling our asbestos testers with reports of plasterboard ceilings having been drilled into which clearly conceal damaged asbestos • Tradesman are reporting privately poor practices going back several years. Some have been sacked or paid off at a high level for airing their concerns • Many tradesmen have expressed concerns privately but will not take a stand in the witness box for fear of being blacklisted by EQC • Some (brave) tradesmen have refused to follow MBIE/EQR guidelines as they feel the inadequacies of the guildelines are unethical
Conclusions • Exposure to asbestos outside during demolitions carries negligible risk to the general public • The earthquake is an opportunity to remove asbestos • Asbestos ceilings should never be encased • EQC and other companies should ascertain and divulge the location of damaged asbestos and provide testing and results where necessary • MBIE guidelines should be followed and tightened up with a public information campaign to match the trade information • Asbestos is clearly a public health risk, not just an occupational health risk
Thanks (1): The Ministry of Health I would like to thank the Ministry of Health for their unprecedented offer of help with this presentation.
Thanks (2) I would especially like to thank • Those brave tradesmen who have put their livelihoods on the line by refusing to put Christchurch families at risk by following bad practice, even when bad practice is “following guidelines” • Those Government agencies and staff who have tenaciously pursued alleged incompetency and alleged corruption • Our children and grandchildren should honour them for their courage
Thanks (3) • Professor Bill Glass • Professor Ian Shaw • The staff of the Ministry of Business, Innovation and Employment