ENGCHEM

• Why worry about chemical safety?

  Chemical Safety is needed for work and activities that involve the use of chemicals to ensure optimal conditions for both human health and the environment.
• Difference of Risks and Hazards

  • Hazard: potential of a substance to cause damage
  • Risk: measure of the probability that harm will occur under defined conditions of exposure to a chemical
• How are risks usually expressed?

  Risks are expressed as probabilities, mathematical statements about the likelihood that harm will be suffered from a hazard
• The process of using statistical methods to estimate how much harm a particular hazard can cause to human health or to the environment. It helps us to establish priorities for avoiding or managing risks.

  Risk assessment
• Risk management is deciding whether or how to reduce a particular risk to a certain degree. 
• Different types of hazards

  • Chemical hazards from harmful chemicals in air, water, soil, food, and human-made products.
  • Biological hazards from more than 1,400 pathogens that can infect humans.
  • Natural hazards such as fire, earthquakes, volcanic eruptions, floods, and storms.
  • Cultural hazards such as unsafe working conditions, unsafe highways, criminal assault, and poverty.
  • Lifestyle choices such as smoking, making poor food choices, drinking too much alcohol, and having unsafe sex.
• Questions of Risk assessment:

  • Hazard Identification: What is the hazard?
  • Probability of risk: how likely is the event?
  • Consequences of risk: What is the likely damage?


  Questions of risk management:

  • Comparative risk analysis: how does it compare with other risks?
  • Risk reduction: how much should it be reduced?
  • Risk reduction strategy: how will the risk be reduced?
  • Financial commitment: How much money should be spent?
• Chemical Hazards


  
  
• From sources such as air, water, soil, food, and human-made products. Can cause health problems or diseases.
• From over 1,400 pathogens that can infect humans. Can cause sickness, disease, or even death.
• Biological Hazards


  
  
• From natural events like fire, earthquakes, volcanic eruptions, floods, and storms. Can cause damage to property, injuries, or loss of life.
• From social and environmental factors such as unsafe working conditions, unsafe highways, criminal assault, and poverty. Can cause injury, illness, or mental distress.
• Toxic Chemical


  A substance that can cause temporary or permanent harm or death to humans and animals.
• Oral Exposure


  Taking in a toxic chemical through eating, drinking, or other mouth contact.
• Inhalation Exposure


  Breathing in a toxic chemical through the air.
• Dermal Exposure


  Touching or coming into contact with a toxic chemical through skin or eyes.
• Occupational Exposure


  Exposure to a toxic chemical in a workplace or as part of a job.
• Environmental Exposure


  Exposure to a toxic chemical through environmental sources like water or air pollution.
• Carcinogen


  A chemical, type of radiation, or virus that can cause or promote cancer.
• Mutagen


  A chemical or form of radiation that causes changes in DNA molecules in cells or increases the frequency of such changes.
• Teratogen


  A chemical that causes harm or birth defects to a fetus or embryo.
• Arsenic


  Causes DNA damage in immune cells.
• Methylmercury


  Affects inflammatory pathways.
• Dioxins


  Causes immunosuppression, weakening the immune system.
• Neurotoxins


  Includes various chemicals that harm the nervous system, including PCBs, methylmercury, arsenic, lead, and certain pesticides.
• PCBs


  Tasteless and odorless substances that are toxic and harmful to living organisms.
• Health effects of PCBs

  Cause learning deficits, cancer, reproductive and endocrine system issues.
• Arsenic


  Used in various industrial processes: glass production, pigment production, textile production, wood preservatives, papers, and ammunition. Also used in agriculture as pesticides and animal feeds.
• Lead

  Common water contaminant, often released from degradation of lead pipes used for water distribution.
• Short-term Effects of Lead Exposure

  A range of symptoms including abdominal pain, constipation, irritability, headache, depression, tiredness, loss of appetite, forgetfulness, and nausea.
• Prolonged Effects of Lead Exposure


  Prolonged exposure increases the risk of high blood pressure and heart disease.
• Methylmercury


  Most toxic form of mercury, especially harmful to humans.
• Toxicology


  The study of the harmful effects of chemicals on humans and other organisms.
• Toxicity


  A measure of the harmfulness of a substance.
• Right Dose Matters


  The dose of a substance is crucial in determining its impact; a small amount might be beneficial, while a larger amount can be harmful.
• Dose Definition


  The dose is the amount of a chemical that a person has ingested, inhaled, or absorbed through the skin.
• Dose Types


  Dose can be ingested, inhaled, or absorbed through the skin or mucous membranes.
• Genetic makeup: each person has different sensitivities to chemicals, as well as varying efficiencies of detoxification systems
• Solubility: determines how long a substance can stay inside the human body