Among the thirteen heavy metals classified as environmental pollutants, which of the following is excluded from this list ?
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Answer: C. Aluminium
Explanation
Aluminium is generally excluded from the specific list of toxic heavy metal environmental pollutants. Although aluminium is abundant in the Earth's crust, its ionic forms exhibit different toxicological properties. Standard environmental toxicology lists focus on transition heavy metals like mercury, lead, cadmium, and arsenic. Heavy metals are typically defined by relatively high atomic weights and distinct metallic toxicological behaviors. Aluminium is a lightweight metal widely used in structural materials, packaging, and water treatment coagulants. Environmental regulations prioritize monitoring heavy metal pollutants due to their persistence and bioaccumulation.
Industrial wastewater treatment guidelines establish permissible discharge limits for regulated toxic heavy metals. Soil chemistry studies differentiate between biologically inert mineral elements and hazardous heavy metal toxins. Public health agencies evaluate metal exposure risks based on established toxicological classification lists. Option A names mercury, a regulated toxic heavy metal known for causing severe neurological damage. Option B suggests arsenic, a highly poisonous metalloid included on standard environmental pollutant lists. Option D proposes lead, a classic toxic heavy metal restricted due to its cumulative poisoning effects.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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