Occupational diseases (Part 6) - Asbestosis

Contains info on the asbestosis related cancers, occupational health cancers and its prevention, workplace stress and ergonomics

1. Occupational Diseases - VI Group B

2. Contents Asbestosis related cancer Occupational health cancers and its prevention Workplace stress on health workers Ergonomics and its objectives

3. 1. Asbestosis related cancers Asbestos cancers are caused by inhaling or swallowing microscopic asbestos fibers . The term “asbestos cancer” most often refers to mesothelioma . Asbestos Exposure Causes Four Types of c ancers: Mesothelioma Lung cancer Laryngeal cancer Ovarian cancer

4. 2. Occupational health cancers Occupational cancer is caused by exposure to carcinogens in the workplace. Carcinogens are agents that cause the development or increase the incidence of cancer. There are three different types of occupational carcinogens : Biological carcinogens - some micro-organisms such as viruses have been known to cause cancer, either by damaging cells directly or by decreasing the body’s ability to control abnormal cells, for example Hepatitis B, HIV viruses and so on . Chemical carcinogens - a number of chemicals are known to be carcinogenic. These chemicals may occur naturally, such as asbestos, be manufactured like vinyl chloride, or be by-products of industrial processes, for example, polycyclic aromatic hydrocarbons.

5. Physical carcinogens - agents such as ionising and ultraviolet (UV) radiation have the potential to cause cancer. Examples of ionising radiation include X-rays and alpha, beta and gamma radiation. UV radiation can be divided into a number of bands such as UV-B, UV-C etc , some of which are known to cause skin cancer. Certain occupational circumstances, such as working as a painter or as a welder are also associated with increased risks of some occupational cancers. Occupational cancers are also called as ‘Industrial cancers’. These constitute another important health problem in the industries because many types of chemicals are employed in the industries, which act as carcinogens.- The most common types of occupational cancers are those of skin, lungs, bladder and blood forming organs (like bone marrow). Agent Factors: These are mainly chemical carcinogens, both organic and inorganic. Organic chemical carcinogens mainly result in lung cancer and inorganic ones mainly result in skin cancer.

6. Environmental Factors: Physical environment like heat and radiation also result in i ndustrial cancers. Influencing Factors: The factors influencing the development of industrial cancers are potency (intensity) of the carcinogen, duration of exposure, degree of personal hygiene and availability of preventive measures. The different types of occupational cancers, their carcinogens and ‘at risk’ group in the industries are as follows : Skin cancer: Carcinogens : Anthracene, coal-tar, soot, pitch, oils and dyes, acids, U-V rays, X-rays. 'At risk' group in the industry: Shepherds, fisherman, road-builders , oil refiners, dye-stuff makers, radiology department staff, tar distillers, coke-oven workers.

7. Lung cancer Carcinogens: Arsenic, asbestos, beryllium, chromium, uranium, tobacco, coal tar, nickel. 'At risk group in the industry: Asbestos factory, uranium-mines, nickel-refineries, gas industry, tobacco industry . Bladder cancer Carcinogens: b- naphthylamine , benzidine , auramine , aromatic amines, para-amino diphenyl, hemotoxins . 'At risk' group in the industry: Aniline industry, rubber industry, electric cable industry. Leukemia Carcinigens : Ionizing radiations (X-rays and gamma rays ), radioactive isotopes. 'At risk' group in the industry: Radiology department, atomic energy research station. Note: ‘Dhoti-cancer’ as described by Khanolkar is not an industrial cancer but caused by mechanical irritation (friction) of dhoti over the skin of waist.

8. Occupational skin cancers also include Mule spinner’s cancer and Chimney sweeper’s cancer (cancer of scrotum). Cancer of the bladder resulting from the infestation of Schistosoma hematobium (a biological agent) is not an industrial cancer. Features of Occupational Cancers They occur in those sites, where the action of carcinogens is constant, most intense and prolonged. They appear after a prolonged exposure of about 10 to 15years . They can occur even after cessation of exposure as in asbestos industry. The average age incidence of occupational cancers is much earlier than that for cancers in general. It is more among men than among women. The localization of the tumor is remarkably constant in any one occupation. Maintenance of high standard of personal hygiene is very important in the prevention of occupational cancers.

9. Occupational cancer can arise from exposure to many substances or from certain occupational circumstances such as : Asbestos fibres ( colorectum , larynx, lung, ovary, pharynx, stomach cancers, mesothelioma ) Wood dusts (nasopharynx, sinonasal cancers ) UV radiation from sunlight (skin cancers ) Metalworking fluids and mineral oils (bladder, lung, sinonasal , skin cancers ) Silica dust (lung cancer ) Diesel engine exhaust (bladder, lung cancers ) Coal tars and pitches (non-melanoma skin cancer ) Arsenic (bladder, lung, skin cancers ) Dioxins (lung cancer ) Environmental tobacco smoke (passive smoke) (lung cancer)Naturally occurring radon (lung cancer ) Tetrachloroethylene (cervix, non-Hodgkin’s lymphoma, oesophagus cancers ) Work as a painter (bladder, lung ) Work as a welder (lung cancer, melanoma of the eye)

10. Prevention of occupational cancers Health Promotion Preplacement examination: This consists of examination of the individual for assessing his physical and psychological capacity , so as to place him in a suitable job (Fitting the job to the worker) e.g . person with skin disease is not placed in handling acids, alkalis and dyes. Sanitation in the working environment : Good housekeeping, ventilation and the cleanliness are mandatory in the industries . Health education : The workers are educated on the following points: To change their attitude towards cancer. To know the ‘Danger signals’ of cancers (Cancer education) To know the hazards of smoking as an aggravating factor in the dusty environment. To maintain high standard of personal hygiene . Control of dust in asbestos industry.

11. Specific Protection Primordial prevention consists of elimination or avoidance of carcinogens in the industry. This also consists of discouraging the workers from adopting harmful lifestyle such as smoking. By the use of protective devices such as : Masks in the asbestos industry, lead apron, lead gloves and dark spectacles in radiology department. Use of barrier creams in dyeing section of the industry. Safety of the worker by wearing ‘Pocket dosimeter’ for personal monitoring of the radiation dose received. Safety of the machine by proper installation and maintenance of X-ray machine, use of efficient fitters so that unwarranted radiations are excluded. They are operated on high kilo-voltage with fast films, so that exposure is reduced to minimum dose.

12. Early Diagnosis and Treatment This is done by ‘Periodical examinations’ of at-risk group of industrial workers, specially in the cancer clinics to detect lesions of early and curable stage. The periodical examinations should be continued even after cessation of exposure to carcinogen. This screening procedure consists of thorough physical examination followed by procedures like blood examination, urine examination, X-ray of chest, cytology, endoscopy and even biopsy. Treatment is given by chemotherapy, surgery, radiotherapy, hormonal therapy or immunotherapy depending upon the type.

13. Disability Limitation This consists of limiting the development of further disability by giving intensive treatment, when the patients come in the advanced stage. Rehabilitation This is given for those who have become handicapped following major surgery such as amputation, lobectomy, etc. They are rehabilitated physically, socially, psycho-logically and vocationally.

14. 3. EFFECT OF STRESS ON WORKERS The United States' National Institute for Occupational Safety and Health defines job stress as the harmful physical and emotional responses that occur when the requirements of the job do not match the capabilities, resources, or needs of the worker. Job stress can, in turn, lead to poor health and even injury . The Impacts of Workplace Stress Workplace stressors are classified as physical and psychosocial. Physical stressors include noise, poor lighting, poor office or work layout, and ergonomic factors, such as bad working postures . Psychosocial stressors are, arguably, the most predominant stress factors. These include high job demands, inflexible working hours, poor job control, poor work design and structure, bullying, harassments, and job insecurity .

15. Workplace stress not only affects the worker, it also has adverse effects on company performance well. The effects of job-related strain are evident in workers' physical health, mental health, and their behavior . Too much stress can be deeply damaging to a person's health . Energy level will decrease , sleep becomes more difficult , eating habits worsen , the heart beats more rapidly and illness becomes more frequent . Workplace stress also has adverse effects on workers' mental health , with an increased risk of anxiety, burnout, depression and substance use disorders . Workers who are stressed at works are more likely to engage in unhealthy behaviors such as cigarette smoking, alcohol and drug abuse, and poor dietary pattern.

16. WHEN EFFECTED BY WORKSTRESS PEOPLE MAY: become increasingly distressed and irritable become unable to relax or concentrate have difficulty thinking logically and making decisions enjoy their work less and feel less committed to it feel tired, depressed, anxious have difficulty sleeping experience serious physical problems, such as heart diseases, etc. disorders of the digestive system, increases in blood pressure, headaches musculo -skeletal disorders (such as low back pain and upper limb disorders)

17. 4. Ergonomics Ergonomics is derived from the Greek words "Ergon" means work and "Nomos" means law. It simply means fitting the job to the work. That means placing the worker in an environment(job) which is adopted to his physiological and psychological capacity . Objectives - The main objective of ergonomics is to achieve the best mutual adjustment between the man and his work, for the human efficiency and well-being . improve efficiency of operation by taking into account a typical person's size, strength, visual acuity and physiological stress such as fatigue, speed or decision making and demands on memory and perception.

18. To minimize the risk of injury, illness, accidents and errors without compromising productivity. To maximize productivity while lowering the risk of Musculoskeletal Disorders (MSDs). MSD develops as a result of long term ergonomic risk factors such as repetition, high forces and awkward postures. Ex of MSDs include- Carpel tunnel syndrome, tendonitis and back disorders. Promote safety and comfort at work station. To reduce physical workloads Improve quality of life

19. References K Park’s PSM A H Suryakantha's PSM www.who.int