A high-selenium lentil dietary intervention in Bangladesh to counteract arsenic toxicity: study protocol for a randomized controlled trial.
BACKGROUND
Millions of people worldwide are exposed to dangerous levels of arsenic (above the WHO water standard of 10 ppb) in drinking water and food. Lack of nutritious foods exacerbates the adverse health effects of arsenic poisoning. The micronutrient selenium is a known antagonist to arsenic, promoting the excretion of arsenic from the body. Studies are in progress examining the potential of using selenium supplement pills to counteract arsenic toxicity. We are planning a clinical trial to test whether high-selenium lentils, as a whole food solution, can improve the health of arsenic-exposed Bangladeshi villagers.


METHODS
A total of 400 participants (about 80 families) will be divided into two groups via computer-generated block randomization. Eligibility criteria are age (≥14) years) and arsenic concentration in the household tube well (≥100 ppb). In this double-blind study, one group will eat high-selenium lentils grown in western Canada; the other will consume low-selenium lentils grown in Idaho, USA. Each participant will consume 65 g of lentils each day for 6 months. At the onset, midterm, and end of the trial, blood, urine and stool, plus hair (day 1 and at 6 months only) samples will be collected and a health examination conducted including assessment of acute lung inflammation, body mass and height, and blood pressure. The major outcome will be arsenic excretion in urine and feces, as well as arsenic deposition in hair and morbidity outcomes as assessed by a biweekly questionnaire. Secondary outcomes include antioxidant status, lipid profile, lung inflammation status, and blood pressure.


CONCLUSIONS
Selenium pills as a treatment for arsenic exposure are costly and inconvenient, whereas a whole food approach to lower the toxic burden of arsenic may be a practical remedy for Bangladeshi people while efforts to provide safe drinking water are continuing. If high-selenium lentils prove to be effective in counteracting arsenic toxicity, agronomic partnerships between Canada and Bangladesh will work to improve the selenium content of the Bangladeshi-grown lentil crops. Results will be presented to the community to promote informed food choices, which may include increasing selenium in their diet.


BACKGROUND
ClinicalTrials.gov NCT02429921.
Department of Ecosystem & Public Health, Faculty of Veterinary Medicine, University of Calgary, 3280 Hospital Drive, Calgary, AB, T2N 4Z6, Canada.
Regina M
RM
Krohn
International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), 68, Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka, 1212, Bangladesh.
Rubhana
R
Raqib
International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), 68, Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka, 1212, Bangladesh.
Evana
E
Akhtar
Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada. bert.vandenberg@usask.ca.
Albert
A
Vandenberg
Department of Ecosystem & Public Health, Faculty of Veterinary Medicine, University of Calgary, 3280 Hospital Drive, Calgary, AB, T2N 4Z6, Canada.
Judit E G
JE
Smits
D001151:Arsenic / Q000009:adverse effects* / Q000652:urine; D020261:Arsenic Poisoning / Q000175:diagnosis / Q000178:diet therapy* / Q000378:metabolism; D001459:Bangladesh; D015415:Biomarkers / Q000652:urine; D001822:Body Burden; D002985:Clinical Protocols; D004032:Diet; D004311:Double-Blind Method; D005243:Feces / Q000737:chemistry; D005260:Female; D006801:Humans; D027806:Lens Plant; D008297:Male; D064167:Recommended Dietary Allowances; D012107:Research Design; D012525:Saskatchewan; D012643:Selenium / Q000008:administration & dosage*; D013997:Time Factors; D016896:Treatment Outcome; D014874:Water Pollutants, Chemical / Q000009:adverse effects* / Q000652:urine; D014881:Water Supply
D015415:Biomarkers; D014874:Water Pollutants, Chemical; D012643:Selenium; D001151:Arsenic
Arsenic body burden; Chronic arsenic poisoning; Dietary intervention; High-selenium lentils