FD: FD: DT:D DN: 398/92 STY: PANEL: Signoroni; Robillard; Apsey DDATE: ACT: KEYW: Asthma; Exposure (chemicals); Smoking.

Transcription

1 FD: FD: DT:D DN: 398/92 STY: PANEL: Signoroni; Robillard; Apsey DDATE: ACT: KEYW: Asthma; Exposure (chemicals); Smoking. SUM: The employer appealed a decision of the Hearings Officer granting benefits for asthma. On the evidence, the worker was exposed to numerous chemicals during the 40 years he worked for the employer. He had a genetic predisposition to development of hypersensitive reactions. He was also a smoker. The Panel found that the worker's asthma was related to these three factors. Employment exposure was a significant factor. The appeal was dismissed. [8 pages] PDCON: TYPE: DIST: IDATE: HDATE: TCO: KEYPER: Marni Stefan, a consultant; M. Bertrand, CAW-TCA Canada, Local 89 XREF: COMMENTS: TEXT:

2 WORKERS' COMPENSATION APPEALS TRIBUNAL DECISION NO. 398/92 This appeal was heard in London on June 4, 1992, by a Tribunal Panel consisting of: A. Signoroni: Vice-Chair, R.H. Apsey : Member representative of employers, M. Robillard: Member representative of workers. THE APPEAL PROCEEDINGS The employer appeals the decision of the WCB Hearings Officer, M. Prpic, dated August 28, The employer was represented by Marni Stefan, a consultant. The worker appeared and was represented by M. Bertrand, the president of CAW-TCA Canada, Local 89. THE EVIDENCE The worker testified. The Panel also considered the Case Description, including one Addendum, additional material covering a relevant WCB policy, and documentary evidence submitted by the worker's representative in the course of the hearing. THE NATURE OF THE CASE It is undisputed that the worker is currently suffering from asthma. The issue in this case - stated simply - is whether the worker's exposure to various chemical substances was a significant causal factor in the development of his asthma. THE PANEL'S REASONS (i) The nature of the employer's operations The worker is 67 years old. On May 29, 1988, he laid off work due to his asthmatic condition. He retired in June 1989 after almost 40 years of work with his last employer, a large chemical company. The employer has two main products at the plant in question. They are soda ash (sodium carbonate) and genetrons (chlorinated fluorinated hydrocarbons). These two products are discussed at length in a report prepared by H. Nelson - a WCB Industrial Hygienist - and directed to Dr. P. Carr, a WCB Occupational Medicine Consultant. The report is dated May 2, 1989, and states the following:

3 2 Soda ash... is manufactured from salt..., limestone..., with ammonia... used in the process. Very simply limestone is calcined to form lime... and carbon dioxide. Ammonia is reacted with the [carbon dioxide] to form ammonium bicarbonate... which is reacted with salt to precipitate out sodium bicarbonate.... The [sodium bicarbonate] is roasted to produce [soda ash]. The ammonia is recovered by treatment with the lime produced from the limestone. A by-product of this process is calcium chloride.... There are three major exposures encountered in the process. They are lime dust, soda ash dust and ammonia gas.... Genetron is manufactured by flourinating carbon tetrachloride... or chloroform with hydrofluoric acid.... The [hydrofluoric acid] used is produced in the plant by reacting fluorspar... which is first calcined to remove water, with sulphuric acid.... One would expect the potential exposures would be [hydrofluoric acid], [chloroform], and [carbon tetrachloride]. In the [Ministry of Labor] reports it is considered that since most of the operations are outdoors, risk of exposure is minimal. However, one report indicated there could be fluorspar dust exposure in the calcining building, and it was recommended housecleaning should be improved.... (ii) The nature of the worker's employment In his testimony the worker confirmed that he held a variety of jobs until the early 1960s and that he was a painter-mason for the last 25 years of his working life. As a painter-mason, he was required to work all over the plant doing masonry work, painting, spraying, sandblasting and tearing down insulation - for purposes of re-insulating - mainly on pipes, tanks and pumps. In his view, the masonry work was the only one that apparently did not directly expose him to harmful substances. However, the same could not be said for the other tasks routinely assigned to him. More specifically, when doing jobs related to painting and spraying, he was exposed to epoxies and activators and in all likelihood, he said, to paint which actually contained isocyanates. Often what he referred to as the "dust" from his spray gun would cause his mask to turn from white to gray. He also mentioned that on several occasions - when spraying - he experienced several symptoms such as shortness of breath, coughing, choking, wheezing, a runny nose and would also bring up mucus. Furthermore, the worker testified that he was also exposed to a lot of "dust" when doing sandblasting work either inside or outside large tanks. Silica sand was used for sandblasting until the substance was banned in Ontario in the early 1980s. Since then, he has been using a silica-free material for sandblasting. When doing this work, he had what was referred to

4 3 as a "dust mask" and a small hood similar to that worn by a beekeeper. However, he indicated that the "dust" would come right up underneath it. Finally, the worker explained that on the insulation work he worked with block asbestos and blankets of fibreglass. When doing this work he had a gauze type of protective mask that at times had to be changed about ten times per shift. However, he stated that such a mask allowed limited protection because often he could feel the "dust" in his mouth, nose and ears. (iii) The total exposure alleged by the worker Specifically, the worker is alleging exposure, in different degrees, to a wide range of chemical substances and related processes - including the impact of the complex interaction among such substances and process - that are listed on a document found in the Case Description and initially filed as an exhibit in the proceedings before the Hearings Officer. This list makes references to the following items: Super 66 (Asbestos Loose); Silica Sand; M-Bed Grout; Tally Grout; Pentox; Zinc & Lead Based Paints; Thinners Nos. 2, 3, 4, 10, 11, 3190; Carboline Paints & Thinners; Fiberglas Batting and Pipe Insulation; Asbestos Blocks & Pipe Insulation; Amor coat (3 part) Paints and Thinners; Stripped asbestos without protective gear for years; Sandblast[ing] for years without backpack & air or plant air; Zelot paints and thinners; Cement dust; Masonry dust; Nerta Patch; Set 10; Imeron Polyurethane Enamel Activator Carbomastic; 2 & 3 Part Paints; Enamel's; Epoxies; Soda Ash; Lime Dust; Fluorspar Dust (Arsenic); Hydrogen Fluoride...; Sulfuric Acid; Ammonia...; Antimony...; Calcium Carbonate...; Calcium Oxide...; Carbon Dioxide...; Carbon Monoxide...; Carbon Tetrachloride...; Chlorine...; Chloroform...; Chromic Acid and Chromates as Salts...; Monochlorodifluoromethane...; Dichlorodifluoromethane...; Trichlorodifluoromethane...; Fluoride...; Fluorine...; Gypsum...; Helium...; Hydrogen...; Hydrogen Chloride...; Hydrogen Fluoride...; Hydrogen Sulphide...; Liquid Propane Gas...; Methane...; Nitrogen...; Notric Acid...; Notric Oxide...; Sodium Hydroxide...; Sulphuric Acid...; Propane.... (iv) Relevant non work-related factors The worker - as mentioned by Dr. P. Carr in a report dated February 24, conceded that he is an atopic individual, namely, that he is suffering from a genetic predisposition to the development of immediate hypersensitive reactions against common environmental antigens. When commenting on this aspect of the case, the worker stated that from the early 1960s his hay fever allergies started to bother him more than in previous years. This genetic predisposition also partly explains the fact that one of the worker's daughters has also been suffering from asthma even though her condition is currently under control.

5 4 The worker also conceded that, in the latter part of 1976, he developed pain in the anterior chest, including the retrosternal area, which gradually became quite severe with a squeezing type of pain that radiated somewhat into the left arm. The diagnosis at the time was: (1) atherosclerotic heart disease, (2) acute coronary occlusion and (3) myocardial infarction. Incidentally, the medical evidence generated at the time of the myocardial infarction also indicates that the worker had a cigarette cough and that until then he smoked about a pack of cigarettes a day. When questioned about his smoking habit, the worker indicated that he stopped smoking after the 1976 myocardial infarction. However, there is conflicting evidence regarding the time when the worker's smoking habit started and the extent of his smoking. Although the worker tended to minimize both the duration and the extent of the smoking habit, the preponderance of the evidence supports the conclusion that he smoked approximately a pack of cigarettes a day - at times more - for approximately 30 years prior to his myocardial infarction at the age of 50. (v) The Hearings Officer decision In the concluding section of the decision under appeal, the Hearings Officer states that Dr. Carr had an opportunity to comment extensively on the merits of this claim. Based on her review of these documents, it is noted that in the opinion of Dr. Carr the medical evidence in support and against the worker's claim was equal in weight. Furthermore, it is also noted that, according to Dr. Carr, it is not necessary to pinpoint the exact sensitizer in the work place, especially if there are a large number of chemicals involved, as in this case. Finally, the Hearings Officer commented on a medical report dated June 20, 1988, prepared by Dr. J. Hellyer, a specialist in the field, indicating that the worker likely was exposed to isocyanates as well as silica and that, on this basis, the worker's asthma is work-related. Bearing in mind these considerations, the Hearings Officer articulates his conclusion as follows: The Hearings Officer, in considering this case must be guided by medical opinion. The Hearings Officer, therefore accepts the opinion of the Board's Occupational Medicine Consultant as well as that of Dr. Hellyer. The Hearings Officer, is therefore satisfied that on the balance of probabilities, it is more probable than not, that the worker's employment and the agents he was exposed to, including the potential for exposure to isocyanates, was a significant contributing factor in the development of his asthma.

6 5 (vi) The employer's submissions The closing remarks of the submissions made by the employer's representative were also filed in written format. For the sake of accuracy, they will be reproduced in full: In conclusion it is the employer's position that the Hearings Officer neglected to properly consider and apply [relevant] legislation and policy guidelines necessary to determine entitlement to [compensation] benefits arising from a workplace exposure. Claim file documentation fails to satisfy [relevant] entitlement criteria. The Hearings Officer's decision ignores the significant weight of evidence in the claim file which clearly establishes a medical history of non-occupational allergic and asthmatic condition enhanced by a hereditary aspect and lifestyle including more than 30 years of cigarette smoking. In addition the employer argues that the Hearings Officer's use of Dr. Carr's statement [previously summarized] is taken out of context. The employer assessment of this statement is that medically it may not be necessary to pin point an exact sensitizer in order to effectively diagnose and treat the condition and this the employer can accept. The doctor's statement, however, when applied to [relevant] legislation and policy in no way provides a basis for entitlement.... Weight of evidence in the claim file fails to satisfy WCB requirement for entitlement to an exposure. Conversely, significant evidence is on file to relate the worker's condition to non-occupational factors.... (vii) The compensation issue On the evidence, it is undisputed that we are faced with a worker who had a genetic predisposition to the development of hypersensitive reactions against common environmental antigens as documented by his long history of hay fever allergies and the asthma condition - apparently under control - suffered by one of his daughters. However, the fact remains that the worker was also exposed to a multitude of chemical substances in the plant where he spent almost 40 years of his working life prior to his early retirement due to his asthma condition. Therefore, the medical legal issue is whether - irrespective of the genetic predisposition suffered - the exposure to the wide range of substances documented by the evidence introduced was a significant causal factor in the development of the asthma condition diagnosed in the late 1970s.

7 6 The determination of this issue cannot be done without addressing two other non-work-related factors that have a causal bearing. One deals with the worker's smoking habit and the other covers the consequences of his myocardial infarction. Dealing with the latter factor first, Dr. G. Sears, a specialist, raised the issue - in a report dated March 28, in the following terms: From my standpoint, this man has two problems. First he has episodes of bronchospasm which I really do not think are related to his heart and I do not feel are pulmonary oedema.... One of course wonders whether this man should continue to work in his present environment and whether it [such environment] in any way is responsible for his chest symptomatology. Finally, there is no doubt that this man has had an inferior wall infarct. Some of his chest distress could be related to Angina but he really does not have very much chest distress now in the absence of bronchospasm. Bearing in mind that Dr. Sears does not place much reliance on the theory of the chest distress attributable to angina and the fact that the medical evidence generated after 1978 does not focus to a great extent on this aspect of the case, we are led to the view that such a theory is far too speculative to be given any causal significance. The same could not be said about the worker's smoking habit previously discussed. This being the case, it is our view that the worker's asthma could be traced back - with a certain degree of reliability - to three factors: the worker's genetic predisposition, the smoking habit and the exposure to a wide range of chemical substances. In her submissions, the employer's representative tended to minimize the role of the chemical exposure in the determination of the compensation issue. However, the Panel notes that - irrespective of the extensive documentation placed before us - there are no medical opinions that refute the positions taken by Drs. Carr and Hellyer, two specialists in the field. Furthermore, their views are also consistent with the position expressed by Dr. A. Reinhartz, a doctor practicing in the field of occupational health. In light of these considerations, the Panel is not prepared to disturb the well-argued decision rendered by the Hearings Officer. We are satisfied that the chemical exposure was a significant causal factor in the development of the worker's asthma. This conclusion is also consistent with the evidence that the worker's condition has, to some extent, improved following his early retirement.

8 7 THE DECISION The appeal is denied. DATED at Toronto, this 16th day of June, SIGNED: A. Signoroni, R.H. Apsey, M. Robillard.