Toxic Agents - Metals and Radioactive Isotopes

These flashcards cover essential topics on toxic agents, specifically focusing on metals and radioactive isotopes, their definitions, effects, and the context of their interactions in the environment.

What defines heavy metals?

Heavy metals are generally defined as metals with relatively high densities, atomic weights, or atomic numbers and are toxic at low concentrations.

List some essential trace metals for humans.

Co, Cu, Cr, Fe, Mn, Ni, Mo, Se, Sn, Zn.

What is the fate of metals in the environment regarding their persistence?

Metals are non-biodegradable.

How do heavy metals enter the human body?

Via food, drinking water, and air.

What are non-essential trace metals?

Metals that are not necessary for human health, e.g., Pb, Hg, Cd, As.

What does the term 'bioaccumulation' refer to?

The accumulation of substances, such as pesticides or metals, in an organism.

What is the significance of metal speciation in ecotoxicology?

Different species of metals impact health and safety in various ways regarding mobility, toxicity, and bioavailability.

Define 'trace elements.'

Elements present in very small amounts in organisms or environments, often playing essential biological roles.

What is the difference between methylmercury and inorganic mercury?

Methylmercury is more easily absorbed by organisms and is more toxic compared to inorganic mercury.

What caused the Minamata disaster?

Industrial discharge of methylmercury into Minamata Bay led to health problems due to fish consumption.

What impact does pH have on metal solubility?

pH dependency affects the solubility of metals in water.

How does the Minamata Convention on Mercury aim to address mercury pollution?

By banning new mercury mines and phasing out existing ones, regulating mercury releases, and addressing health issues related to mercury.

What are organometallic compounds?

Compounds containing a carbon-metal bond, often highly toxic, such as methylmercury.

What historical event led to the release of numerous radioactive isotopes and affected Scandinavia?

The Chernobyl accident on April 26, 1986.

What does the term 'bioconcentration factor (BCF)' refer to?

The ratio of a substance's concentration in an organism to its concentration in the environment.

Why are rare earth elements important for green technologies?

They are used in devices like wind turbines, batteries, and electric vehicles.

What are some anthropogenic sources of cadmium contamination?

Battery manufacturing, mining activities, and smelting.

What does 'oxidative stress' in the context of heavy metals mean?

Damage caused by free radicals generated by heavy metal toxicity, impacting DNA and other biological molecules.

How can humans be exposed to radioactive iodine, and what is its risk?

Exposure occurs through inhalation or ingestion, increasing the risk of thyroid cancer.