Frontiers in Occupational Health and Safety

If a disease demonstrates frequency in a group of people of a particular occupation more than the one that takes place in general public and has a demonstrable record between a particular illness and specific work/work-related environment, it is classified as an occupational disease. The development of a new class of occupational disorders is by-product of the recent uncontrolled man-man, man-machine and managents’ interaction. A small percentage of workers amongst the total working population of the world have access to occupational health related services, the access gets diminished if the worker is a child labour from a developing country. Moreover, the constant evolution of newer work areas and substances has led to continuous revision of list of causative agents and occupational health hazards by various agencies. “Diving medicine” is one such emerging branch of medicine dealing with specific health aspects of deep sea divers. The study of cause-effect relationship of occupational diseases will contribute towards reducing cases of work related disorders. Biological agents become causative agents through generation of bio aerosols or as routine infectious agents affecting biomedical scientists, laboratory technicians, medical and paramedical staff. The duration of exposure and varying doses (low-high) of hazardous chemical complexes are a source of a range of disorders from long term effects like neuro- behavioural dysfunction to immediate effects like burns. Some substances sensitise both airways and skin leading to respiratory and skin disorders. Similarly, the intensity and duration of exposure to the physical agents lead to an array of disorders ranging from white finger vibration, trench foot, barotrauma upto cancer. Besides exposure to biological, chemical, physical, ergonomic disease causing agents a worker is also prone to altered psychosocial agents at workplace. Violence and accidents occur at workplace. Discrimination (gender/ethnic/ migrant status), disturbed circadian rhythm, work pressure, lack of job satisfaction and social life leading to depression and anxiety have become a new normal in working class.

Human brain is the most complex organ that controls various complicated functions like behavior, learning, talking, memorizing, organizing, listening, performance of routine skills and interaction with environment. The vulnerability of brain towards toxic effects of occupational hazards is very high due to the presence of high amount of polyunsaturated fatty acids and high metabolism. Interference with xenobiotics or occupational hazards disrupts homeostatic processes and may cause long lasting effects in humans including behavioural abnormalities, cognitive deficits, depression and movement disorders. Prolonged exposure to toxicants and occupational hazards leads to altered membrane and lipid rafts leading to various neurological disorders including Parkinson’s and Alzheimer’s disease. Therefore, a deep knowledge of occupation induced hazards mediated alteration on normal brain development and function will add to the research of minimizing this risk. In the present chapter, different occupational hazards are discussed with their deleterious effects on human brain.

Cancer is one of the most dreaded diseases of mankind that causes alarming mortality and morbidity in humans. According to International Labour Office (ILO), Occupational cancer is the most common work-related cause of death, leaving accidents and account for 32% of all work-related deaths worldwide leaving accidents and other occupational diseases well behind. It has long been evident that cancer has a multi-factorial etiology and is a multi-stepped process involving initiation, promotion and tumor progression. Studying occupational cancer is very challenging because of the long latency of cancer and the involvement of many factors in the development of cancer including family history, personal characteristics, dietary and personal habits besides exposure to cancer-causing agents in the workplace and environment. Occupational factors continue to be highly prevalent in new or upgraded IARC (International Agency for Research on Cancer) classifications in last decade. Inhalation, skin exposure and ingestion are significant modes of exposure of chemicals resulting in Cancer.Prevention of occupational cancer is a multistep strategy which involves eradication/minimization of carcinogenic process or agent coupled with good work /hygiene practices, employee education /counselling and workplace monitoring.

In order to deliver quality health care to the community and experience medicine as rewarding career, professionals in healthcare sector also need to be healthy. According to International Labour Organisation (ILO)/World Health Organisation (WHO) declaration on health services 2005, Health care workers are all persons involved in actions whose main intent is to enhance health. They comprise all those individuals who provide health facilities, such as doctors, nurses, pharmacists, laboratory technicians, support workers such as finance officers, cooks, drivers, cleaners and security. Healthcare workers also include persons involved in long term care, community based care, home care and informal caregivers. Nosocomial infections are cross infections acquired from one patient by another or by doctors, nurses and other hospital staff while at work. The various risk factors to which healthcare professionals are exposed to are categorized as Biological, Chemical, Physical, Psychosocial, Electrical and Ergonomic. Trachoma, Leprosy, AIDS and Tetanus are some of the Surface infections to which health workers are exposed whileEmerging infectious diseases include SARS, H1N1, MERS, Chikngunya, Zika virus etc. A number of infectious diseases are avoidable if proper preventive measures like Hand wash (How and when), masks, sanitization, vaccination and post exposure treatments are followed by medical staff. Moreover, medical and paramedical staff with healthy habits is more likely to inculcate healthy behaviour in their patients.

A lab worker was severely burned working with a bottle of t-butyl-lithium. Tertiary butyl-lithium is a highly volatile chemical and spontaneously catches fire upon exposure to air. A scientist died working with bacteria; the infection that killed the scientist may be connected to a virus that causes small pox. Accidents in academic settings happen quite frequently every year in developed and developing countries. Most of the time, laboratories are fully stocked with hazardous chemicals such as strong acids, flammable items and neurotoxins. They also have natural gas-guzzling Bunsen burners and high-pressure cookers called autoclaves. Additionally, biology labs often have infectious organisms, chemistry labs have explosives, and physics labs often have lasers. Factually, everywhere you turn, there is something that could seriously injure you. But we cannot stop them from working on those things which improve the health of mankind. On the other hand, we have to take precautions in the laboratory for safe handling of biological materials and living organisms. The primary purpose of this chapter is to learn work safely with biological materials as well as to address other issues such as knowledge of specific biological agents and toxins, quality laboratory management practices and an overall safety culture.

Stress is a 21st century biproduct of globalization coupled with industrialization. WHO recognizes stress as one of the biggest challenges of our time. Two theoretical models are accepted to study stressful psychosocial work environment Job-Demand-Control (JDC) and Effort Reward Imbalance (ERI) or Organizational Justice (OJ) model. The work stressors like accumulating anxiety, insomnia or excessive sleepiness and depression coupled with lack of job satisfaction, diminished social life due to work pressure might lead to burn out occasionally leading to suicidal tendencies among workers. Shift work and migration are other major contributors to stress. A growing body of research underlines the significance of sleep for regeneration as good quality of sleep improves attention, focus and ameliorates stress. Sleep-wake cycle is regulated through neurons in hypothalamus as clock genes and Melatonin synchronize circadian rhythm which in turn influences emotion, behavior and cognition. Stress is a precursor of many disorders. Stress negatively stimulates Hypothalamic-Pituitary-adrenal axis and Autonomic Nervous Systemwhile circadian rhythm collapses during ageing. Allostatic adjustments are undertaken to maintain Homeostasis to prevent disease. The dysregulation of Allostatsis end in tertiary outcomes like cancer, depression, stroke, obesity, diabetes, Alzheimer’s disease. Organizations are encouraged now-a-days by researchers to educate workers regarding sleep as a component of workers’ health. Proper sleep is like basic practice of sanitation and hygiene which if properly undertaken helps avert a number of health related issues.