DE
DefZone.Net

Kien thuc cong nghe & giai tri

Wiki Article

Arsenic cycle

Nguồn dữ liệu từ Wikipedia, hiển thị bởi DefZone.Net

Xem trên WikipediaBài ngẫu nhiên khác

The arsenic (As) cycle is the biogeochemical cycle of natural and anthropogenic exchanges of arsenic with the environment.[1] The cycle is of interest because arsenic is detrimental to human health. The World Health Organization recognizes that inorganic arsenic is extremely toxic for humans (U.S. EPA maximum of 10 ppb in water) and detrimental to aquatic life.[2] Arsenic toxicity can harm nearly every organ system within the human body, as well as causing lung and skin cancer.[3][4][5] While treatment for arsenic toxicity is possible, prevention or water treatment tends to be the safest solution.[6]

Reservoirs and fluxes

[edit]
Arsenic biogeochemical cycle with fluxes in kg/yr and reservoirs in kg. Fluxes are depicted with black arrows, while anthropogenic fluxes are red. Fluxes are between the lithosphere, pedosphere, hydrosphere, and atmosphere.[5]

Although many arsenic-containing minerals have been identified,[7] only a few are of economic significance, mainly arsenopyrite (FeAsS) and tennantite. The principal problematic mineral-sourced arsenic comes from smelting of ores that contain traces of arsenic.[8] Sedimentary rocks bearing coal and shale may also contain high As.[9] Major fluxes of As from the lithosphere to the atmosphere are volcanic emissions.[5]

Freshwater and groundwaters commonly contain <1 ppb of As.[5] The concentration of As is pH dependent; acidic conditions mobilize As at pH <5.[5] Oxic seawater contains As(III) as arsenate (average of 1.7 ppb).[10] Major sinks include sedimentation and subduction.[5]

Anthropogenic arsenic sources

[edit]
Main article: Arsenic § Applications

Arsenic is a component of a few man-made materials: wood preservatives, animal feed supplements, and some specialty alloys.

It is also emitted from coal-based power plants and smelting, and refining operations.[5][11] As is also present in many industrial and agricultural sources such as herbicides, fertilizers, and pesticides.[12] Some As is emitted from steel and glass production, and forest and grassland burning.[5] Major locations that contribute significantly to As pollution are South Asia, West-central Africa, Western Europe, and Latin America.[12]

Arsenic toxicity

[edit]
Main article: arsenic poisoning

The toxicity of As is well known.[13]

  • Arsenopyrite (AsFeS) is the most abundant As mineral
    Arsenopyrite (AsFeS) is the most abundant As mineral
  • Signs of arsenic poisoning include changes in skin pigmentation. This person experienced As poisoning due to contaminated water.
    Signs of arsenic poisoning include changes in skin pigmentation. This person experienced As poisoning due to contaminated water.

See also

[edit]

References

[edit]
  1. ^ Cullen, William R.; Reimer, Kenneth J. (1989). "Arsenic speciation in the environment". Chemical Reviews. 89 (4): 713–764. doi:10.1021/cr00094a002. hdl:10214/2162.
  2. ^ Humans, IARC Working Group on the Evaluation of Carcinogenic Risks to (2012). ARSENIC AND ARSENIC COMPOUNDS. International Agency for Research on Cancer.
  3. ^ "Arsenic Toxicity: What are the Physiologic Effects of Arsenic Exposure? | Environmental Medicine | ATSDR". archive.cdc.gov. 2023-05-25. Retrieved 2026-02-25.
  4. ^ Masuda, Harue (2018). "Arsenic cycling in the Earth's crust and hydrosphere: interaction between naturally occurring arsenic and human activities". Progress in Earth and Planetary Science. 5 (1) 68. Bibcode:2018PEPS....5...68M. doi:10.1186/s40645-018-0224-3. ISSN 2197-4284. S2CID 53645300.
  5. ^ a b c d e f g h Matschullat, Jörg (2000). "Arsenic in the geosphere — a review". Science of the Total Environment. 249 (1–3): 297–312. Bibcode:2000ScTEn.249..297M. doi:10.1016/S0048-9697(99)00524-0. PMID 10813460.
  6. ^ "Treatment Options and Technologies - Arsenic - University of Maine". Arsenic. Retrieved 2026-04-29.
  7. ^ Mandal, B (2002-08-16). "Arsenic round the world: a review". Talanta. 58 (1): 201–235. doi:10.1016/s0039-9140(02)00268-0. ISSN 0039-9140.
  8. ^ WHO Arsenic Compounds, Environmental Health Criteria 224. Geneva: World Health Organization. 2001.
  9. ^ Smedley, P.L; Kinniburgh, D.G (2002-05-01). "A review of the source, behaviour and distribution of arsenic in natural waters" (PDF). Applied Geochemistry. 17 (5): 517–568. Bibcode:2002ApGC...17..517S. doi:10.1016/S0883-2927(02)00018-5. ISSN 0883-2927. S2CID 55596829.
  10. ^ Bruland, KW (1983). Trace elements in sea water In Riley JP, Chester R. editors. London: Academic Press. pp. 157–220.
  11. ^ Schlesinger, William H.; Klein, Emily M.; Vengosh, Avner (2022-11-17). "The Global Biogeochemical Cycle of Arsenic". Global Biogeochemical Cycles. 36 (11). doi:10.1029/2022GB007515. ISSN 0886-6236.
  12. ^ a b Sevak, Pooja; Pushkar, Bhupendra (2024-01-01). "Arsenic pollution cycle, toxicity and sustainable remediation technologies: A comprehensive review and bibliometric analysis". Journal of Environmental Management. 349 119504. doi:10.1016/j.jenvman.2023.119504. ISSN 0301-4797.
  13. ^ Michael., Kosnett (1990). Arsenic toxicity. U.S. Dept. of Health & Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry. OCLC 25527050.