Discuss the characteristics of three toxic agents.

1. Arsenic: Arsenic is a highly toxic metalloid that can be found in various forms, including inorganic arsenic compounds and organic arsenic compounds. Inorganic arsenic is more toxic than organic arsenic and is commonly found in contaminated water, soil, and food. Arsenic poisoning can occur through ingestion, inhalation, or skin contact, and can lead to symptoms such as abdominal pain, vomiting, diarrhea, and in severe cases, organ failure and death. Chronic exposure to arsenic has been linked to an increased risk of cancer, cardiovascular disease, and neurological disorders.

2. Lead: Lead is a heavy metal that is highly toxic to humans, particularly to children and pregnant women. Lead exposure can occur through ingestion of contaminated food or water, inhalation of lead dust or fumes, or skin contact with lead-containing products. Lead poisoning can cause a range of symptoms, including abdominal pain, fatigue, irritability, and cognitive impairment. Chronic exposure to lead can lead to serious health effects, such as developmental delays in children, kidney damage, and neurological disorders.

3. Mercury: Mercury is a toxic heavy metal that exists in various forms, including elemental mercury, inorganic mercury compounds, and organic mercury compounds such as methylmercury. Mercury exposure can occur through ingestion of contaminated fish and seafood, inhalation of mercury vapors, or skin contact with mercury-containing products. Mercury poisoning can cause symptoms such as tremors, memory loss, and mood swings, and in severe cases, can lead to kidney damage, respiratory failure, and neurological disorders. Chronic exposure to mercury has been linked to developmental delays in children, cardiovascular disease, and reproductive problems.