# Andrew A. Meharg
**Andrew Alexander Meharg** (born name as printed on his [Royal Irish Academy](https://www.edgepedia.org/royal-irish-academy) record) is a biogeochemist and environmental scientist known for research showing that rice is the major dietary source of inorganic arsenic, a class 1 non-threshold carcinogen.[1](https://impact.ref.ac.uk/casestudies/CaseStudy.aspx?Id=43294) He holds a BSc from [Queen's University Belfast](https://www.edgepedia.org/queens-university-belfast) (1986) and a PhD from the [University of Aberdeen](https://www.edgepedia.org/university-of-aberdeen) (1989), and according to the Queen's University Belfast Research Portal, he is listed as an Emeritus Professor in the School of Biological Sciences, affiliated with the Institute for Global Food Security.[2](https://www.ria.ie/members/professor-andrew-alexander-meharg/) • [3](https://pure.qub.ac.uk/en/persons/andy-meharg/) • [4](https://www.qub.ac.uk/News/find-an-expert/ProfessorAndyMeharg.html) He is a Fellow of the Royal Society of Edinburgh and a Member of the Royal Irish Academy in Earth and Environmental Sciences.[3](https://pure.qub.ac.uk/en/persons/andy-meharg/) • [2](https://www.ria.ie/members/professor-andrew-alexander-meharg/)
| Fact | Detail |
|---|---|
| Field | Biogeochemistry; arsenic and cadmium cycling through food chains[3](https://pure.qub.ac.uk/en/persons/andy-meharg/) • [5](https://theconversation.com/profiles/andy-meharg-143461) |
| Degrees | BSc, Queen's University Belfast, 1986; PhD, University of Aberdeen, 1989[2](https://www.ria.ie/members/professor-andrew-alexander-meharg/) |
| Position | Emeritus Professor, School of Biological Sciences, Queen's University Belfast[3](https://pure.qub.ac.uk/en/persons/andy-meharg/) |
| Signature work | Research showing that rice is the major dietary source of inorganic arsenic[1](https://impact.ref.ac.uk/casestudies/CaseStudy.aspx?Id=43294) |
| Policy impact | EU and WHO arsenic-in-rice regulations and guidance standards[4](https://www.qub.ac.uk/News/find-an-expert/ProfessorAndyMeharg.html) |
| Honours | Fellow of the Royal Society of Edinburgh; Member of the Royal Irish Academy[3](https://pure.qub.ac.uk/en/persons/andy-meharg/) |
## Education and career
Meharg began his academic career in chemistry at Queen's University Belfast, focusing on plants and soils.[4](https://www.qub.ac.uk/News/find-an-expert/ProfessorAndyMeharg.html) According to the University of Aberdeen, after his 1989 doctorate he spent years at the university studying the physiology of [arsenic metabolism](https://www.edgepedia.org/arsenic-metabolism) in wild plants.[6](https://www.abdn.ac.uk/news/3414/) The turn to rice came when a Bangladeshi PhD student he was supervising came to Aberdeen to study arsenic in rice; the initial studies were funded through a Commonwealth Universities PhD Scholarship and two Commonwealth Universities Visiting Fellowships, all recipients Bangladeshi.[6](https://www.abdn.ac.uk/news/3414/) • [7](https://www.abdn.ac.uk/sbs/research/impact/the-problem-of-arsenic-and-rice/) Later grants include a 2007–2011 BBSRC-DFID award of £650,000 on genetic approaches to lowering inorganic arsenic in rice, and FSA awards totalling £191,000 (2007–13) including effects of cooking on arsenic removal.[1](https://impact.ref.ac.uk/casestudies/CaseStudy.aspx?Id=43294) Queen's profiles list him there as Professor of Plant and Soil Sciences and, in the research portal, as Emeritus Professor.[4](https://www.qub.ac.uk/News/find-an-expert/ProfessorAndyMeharg.html) • [5](https://theconversation.com/profiles/andy-meharg-143461) • [3](https://pure.qub.ac.uk/en/persons/andy-meharg/)
## Representative work
His 2002 work identified that irrigating paddy rice with arsenic-contaminated groundwater in Bangladesh and [West Bengal](https://www.edgepedia.org/west-bengal) was a concern, followed by the first published field survey of arsenic in rice grain and paddy soil in Bangladesh.[1](https://impact.ref.ac.uk/casestudies/CaseStudy.aspx?Id=43294) Contamination arises from natural soil arsenic, exacerbated by irrigation with arsenic-polluted groundwater, base and precious metal mining, and use of municipal solid waste as fertilizer.[6](https://www.abdn.ac.uk/news/3414/)
A 2010 review in *Annual Review of Plant Biology*, "Arsenic as a Food Chain Contaminant", explains the mechanism: flooded paddy cultivation mobilizes arsenite, which rice takes up inadvertently and efficiently through the silicon transport pathway.[8](https://www.annualreviews.org/content/journals/10.1146/annurev-arplant-042809-112152) A 2009 survey compiled total arsenic data for 901 polished rice samples from 10 countries on 4 continents; median contents varied 7-fold, lowest in Egypt (0.04 mg/kg) and India (0.07 mg/kg), highest in the U.S. (0.25 mg/kg), and France (0.28 mg/kg).[9](https://pubmed.ncbi.nlm.nih.gov/19350943/)
## Impact on food standards
According to the University of Aberdeen, the Aberdeen research led the [European Food Safety Authority](https://www.edgepedia.org/european-food-safety-authority) to undertake a major review of arsenic in foods, after which the WHO withdrew its inorganic arsenic Provisional Maximum Tolerable Daily Intake as based on flawed calculations and too high.[7](https://www.abdn.ac.uk/sbs/research/impact/the-problem-of-arsenic-and-rice/) • [1](https://impact.ref.ac.uk/casestudies/CaseStudy.aspx?Id=43294) In May 2009 the UK Food Standards Agency advised that children aged 1 to 4.5 should not have rice drinks, since a daily 280 milliliters could double the more harmful form of arsenic they consume.[1](https://impact.ref.ac.uk/casestudies/CaseStudy.aspx?Id=43294) In January 2016 the EU imposed a maximum limit on inorganic arsenic in rice products; a subsequent QUB-led study in PLOS ONE found 50% of baby rice food products still contained illegal levels, and nearly 75% of rice-based products marketed for infants exceeded the EU standard.[10](https://alumni.qub.ac.uk/baby-food-arsenic-prof-meharg)
## Books and public engagement
He published the 171-page book *Arsenic and rice* (2012), covering sources of arsenic to paddy soils, global patterns, human exposures and health risks, and agronomic mitigation; it highlights the highest-consumption populations, including Southern and South East Asians, weaning babies, gluten intolerance sufferers, and consumers of rice milk.[11](https://repository.rothamsted.ac.uk/id/eprint/18344/) His consumer advice is to increase contribution from other grains such as wheat, oats, barley, and millet, and to source rice from low-arsenic regions such as Egyptian short grain and Himalayan Basmati.[6](https://www.abdn.ac.uk/news/3414/) He and his team developed a rice cooker that works like a [coffee percolator](https://www.edgepedia.org/coffee-percolator); per Meharg's earlier research, percolating rice could remove up to 85% of its arsenic.[4](https://www.qub.ac.uk/News/find-an-expert/ProfessorAndyMeharg.html) • [10](https://alumni.qub.ac.uk/baby-food-arsenic-prof-meharg)
## References
1. [REF 2014 Impact Case Study: Discovery of rice as the major dietary source of inorganic arsenic (University of Aberdeen)](https://impact.ref.ac.uk/casestudies/CaseStudy.aspx?Id=43294)
2. [Professor Andrew Alexander Meharg – Royal Irish Academy](https://www.ria.ie/members/professor-andrew-alexander-meharg/)
3. [Andy Meharg – Queen's University Belfast Research Portal](https://pure.qub.ac.uk/en/persons/andy-meharg/)
4. [Professor Andy Meharg | Queen's University Belfast Find an Expert](https://www.qub.ac.uk/News/find-an-expert/ProfessorAndyMeharg.html)
5. [Andy Meharg – The Conversation profile](https://theconversation.com/profiles/andy-meharg-143461)
6. [Work of Aberdeen arsenic expert 'highly cited' | University of Aberdeen](https://www.abdn.ac.uk/news/3414/)
7. [The problem of arsenic and rice | University of Aberdeen](https://www.abdn.ac.uk/sbs/research/impact/the-problem-of-arsenic-and-rice/)
8. [Arsenic as a Food Chain Contaminant (Annual Review of Plant Biology, 2010)](https://www.annualreviews.org/content/journals/10.1146/annurev-arplant-042809-112152)
9. [Geographical variation in total and inorganic arsenic content of polished (white) rice (PubMed)](https://pubmed.ncbi.nlm.nih.gov/19350943/)
10. [Baby food arsenic Prof Meharg – Queen's University Belfast](https://alumni.qub.ac.uk/baby-food-arsenic-prof-meharg)
11. [Arsenic and rice (Meharg & Zhao, 2012) – Rothamsted Repository](https://repository.rothamsted.ac.uk/id/eprint/18344/)
12. [Andrew Meharg – QUADRAT DTP profile](https://www.quadrat.ac.uk/profiles/andrew-meharg/)
13. [We need tougher solutions for rice's arsenic problem | The Grocer](https://www.thegrocer.co.uk/comment-and-opinion/we-need-tougher-solutions-for-rices-arsenic-problem/552958.article)
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*Topic: Encyclopedia › Physical world and mathematics › Physical and mathematical scientists › Earth and climate scientists › Researchers in geology, geophysics, geochemistry, and hydrology › Environmental geochemistry and soils*
*Initially written Sep 21, 2026 · Reviewed: Sep 25, 2026 · Edited: Sep 25, 2026; Oct 11, 2026; Oct 15, 2026 · Last review: Sep 25, 2026*
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