Roxarsone

Roxarsone
Names
IUPAC name
4-Hydroxy-3-nitrobenzenearsonic acid
Systematic IUPAC name
(4-Hydroxy-3-nitrophenyl)arsonic acid[1]
Other names
3-Nitro-4-hydroxyphenyl arsonic acid
2-Nitrophenol-4-arsonic acid
Identifiers
1976533
121-19-7 Yes
ChEBI CHEBI:35817 Yes
ChEMBL ChEMBL1321154
ChemSpider 4925 Yes
EC number 204-453-7
1221211
Jmol-3D images Image
Image
KEGG D05771 Yes
MeSH Roxarsone
PubChem 5104
RTECS number CY5250000
UN number 3465
Properties
C
6
AsNH
6
O
6
Molar mass 263.0365 g mol−1
Melting point >300 °C
Hazards
GHS pictograms
GHS signal word DANGER
H301, H331, H410
P261, P273, P301+310, P311, P501
EU classification T N
R-phrases R23/25, R50/53
S-phrases S20/21, S28, S45, S60, S61
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 Yes verify (what is: Yes/?)
Infobox references

Roxarsone is an organoarsenic compound that is widely used in poultry production as a feed additive to increase weight gain and improve feed efficiency, and as a coccidiostat.[2] The drug is also approved in the United States for use in pigs.[2] Roxarsone is marketed as 3-Nitro by Zoetis, a former subsidiary of Pfizer now a publicly traded company. In 2006, approximately one million kilograms of roxarsone were produced in the U.S.[3]

Roxarsone is one of four arsenical animal drugs approved by the U.S. Food and Drug Administration (FDA) for use in poultry and/or swine, along with nitarsone, arsanilic acid, and carbarsone.[2] In September 2013, the FDA announced that Zoetis and Fleming Laboratories would voluntarily withdraw current roxarsone, arsanilic acid, and carbarsone approvals, leaving only nitarsone approvals in place.[4] Roxarsone is banned in the European Union.[5]

Production and applications

Roxarsone is a derivative of phenylarsonic acid (C6H5As(O)(OH)2). It was first reported in a 1923 British patent that described the nitration and diazotization of arsanilic acid.[6] When blended with calcite powder, it is used in poultry feed premixes and is usually available in 5%, 20% and 50% concentrations.

Controversy

Roxarsone has attracted attention as a source of arsenic contamination of poultry and other foods.[7][8] In July 2011, Pfizer suspended sale of roxarsone in the U.S. in response to a study by the Food and Drug Administration (FDA);[9] the FDA found that roxarsone use was associated with elevated levels of inorganic arsenic in chicken livers.[10] An FDA press release stated that the findings raised "concerns of a very low but completely avoidable exposure to a carcinogen."[9] The voluntary suspension does not preempt Pfizer from selling roxarsone in the future, as FDA has not withdrawn its approval to market the drug in the U.S.[11][12] As of 2011, roxarsone was approved for use in 14 other countries as well.[11]

A 2013 market basket study linked the use of roxarsone and other arsenical feed additives to increased levels of inorganic arsenic in chicken breast meat.[13][14] Breast meat from conventionally produced chickens (in which arsenical use is permitted under U.S. law) had three times more inorganic arsenic than did breast meat from chickens produced according to USDA Organic standards. (The USDA Organic program prohibits arsenical use in organic chicken production.[15]) The researchers also found that inorganic arsenic concentrations were almost three times higher in samples with detectable levels of roxarsone than in samples without detectable roxarsone.

References

  1. "Roxarsone - PubChem Public Chemical Database". The PubChem Project. USA: National Center for Biotechnology Information. Descriptors Computed from Structure.
  2. 2.0 2.1 2.2 U.S. Food and Drug Administration (June 8, 2011). "Questions and Answers Regarding 3-Nitro (Roxarsone)".
  3. Hileman, B. (April 9, 2007). "Arsenic in Chicken Production". Chemical and Engineering News. pp. 34–35.
  4. U.S. Food and Drug Administration (September 20, 2011). "FDA Response to Citizen Petition on Arsenic-based Animal Drugs".
  5. Some Arsenic With That Supermarket Chicken? Tom Philpott Sat Jun. 11, 2011
  6. GB 226255 19230718
  7. Institute for Agriculture and Trade Policy (April 4, 2006). "Playing Chicken: Avoiding Arsenic in Your Meat".
  8. Consumer Reports (November 2012). "Arsenic in your food".
  9. 9.0 9.1 U.S. Food and Drug Administration (June 8, 2011). "FDA: Pfizer will voluntarily suspend sale of animal drug 3-Nitro".
  10. Cevallos, M. (June 9, 2011). "Arsenic-containing drug in chicken feed to be pulled from U.S". LA Times.
  11. 11.0 11.1 Gardiner Harris and Denise Grady (June 8, 2011). "Pfizer Suspends Sales of Chicken Drug With Arsenic". New York Times.
  12. U.S. Food and Drug Administration. "Animal Drugs @ FDA".
  13. KE Nachman, PA Baron, G Raber, KA Francesconi, A Navas-Acien, DC Love (2013). "Roxarsone, Inorganic Arsenic, and Other Arsenic Species in Chicken: A U.S.-Based Market Basket Sample" (PDF). Environmental Health Perspectives.
  14. Sabrina Tavernise (May 11, 2013). "Study Finds an Increase in Arsenic Levels in Chicken". New York Times.
  15. "7 C.F.R. §205 - National Organics Program". Code of Federal Regulations.

Further reading

External links