CONSUMPTION OF UNSAFE FOODS: EVIDENCE FROM HEAVY METAL, MINERAL AND TRACE ELEMENT CONTAMINATION

1. CONSUMPTION OF UNSAFE FOODS: EVIDENCE FROM HEAVY METAL, MINERAL AND TRACE ELEMENT CONTAMINATION (ToR # 16) Team Members Dr. M. Rafiqul Islam Dr. M. Jahiruddin Dr. Md. Rafiqul Islam Dr. Md. A. Alim Dr. Md. Akteruzzaman

2. Food security and Food contamination Food security exists when all people, at all times, have physical and economic access to enough safe and nutritious food to meet their dietary needs and food preferences for an active and healthy lifestyle (World Food Summit, 1996) Sources of Heavy Metal Contamination in Foods Industrial wastes & effluents Fertilizers Fossil fuels Sewage sludge Contaminated underground water

3. Heavy Metal Contamination in Bangladesh:Glimpses Industrial discharge Industrial discharge Veg. washed with contaminated water Roadside contamination

4. Major Routes of Heavy Metal Contamination: Example arsenic Fish

5. OBJECTIVES • Assess the concentration of major foods and beverages consumed by poor and non-poor households for heavy metals (Pb, Cd, Co, Hg, Sb, Li and As),minerals (Ca, Mg, Na, K) and trace elements (Fe, Mn, Zn, Cu, Mo Se, Al, Ni and Cr) • Assess the extent of exposure to heavy metals, minerals and trace elements through food intake by poor and non-poor households and the potential health implications iii) Draw implications and provide suggestions for actions to reduce contamination

6. METHODOLOGY

7. SAMPLE COLLECTION • Food samples were collected from 10 different shops of Kawranbazar and Hazaribagh and 3 supermarkets & 7 shops of Gulshan market • Eighty composite food samples were collected from each of the three markets • Standard operating procedures were followed for processing of food samples (NIN, 2009)

8. PROCESSING AND COOKING OF FOODS:RICE Weight of the parboiled rice (coarse and fine grain) recorded Washed with tap water Cooked by both absorption (rice:water=1:3) and draining method (rice:water=1:5) Excess water discarded in case of draining out method Weight of raw and cooked rice recorded and calculate YIELD FACTOR A sub-sample was kept in oven to obtain dry weight

9. CHEMICAL ANALYSIS Digestion Food samples were digested with Ultrapure grade HNO3 and H2O2 using the digestion block at 115 °C. Determination of elements Digested samples were analyzed for elements using ICP-MS in SGS laboratory, Bangladesh Ltd Reliability The reliability of the procedure was assessed by comparison with the Certified Reference Material GBW(E)080684.

10. RESULTS

11. Comparative Mineral Content in Rice using Two Cooking Methods Decrease in mineral content through draining method Loss of water causes leaching of nutrients

12. Mineral content of Puffed Rice Loss of moisture increased mineral contents Use of salt water to prepare puffed rice Fe and Al intake from utensil and sand

13. Cd and As conc. in rice Cd As High Cd in Gulshan market High As in Gulshan market Preliminary results showed higher values Need further validation Safe limit for Cd: 50 microgram/60 kg bw/day

14. LEAD CONC.IN RICE AND PULSES Wide variation of Pb in foods from different markets Any conc. of Pb is harmful

15. ZINC CONC. IN VEGETABLES

16. ARSENIC CONC. IN VEGETABLES As level: Very low Any conc of Arsenic is harmful

17. LEAD CONC. IN VEGETABLES Hazaribagh: High Pb content Any concentration of lead is harmful

18. CADMIUM CONC. IN VEGETABLES Spinach and Amaranth: High Cd content

19. SELENIUM CONC. IN FISHES High variability among markets Relatively higher in Gulshan market

20. ELEMENTAL CONCENTRATION IN FOODS • Variation in mineral, trace elements and heavy metals in foods was noted which is attributed to source and location • Cooking rice by draining method decreased the concentration of elements compared to cooking rice by absorption method • Rice grains had higher conc. of As, Pb and Cd • Puffed rice had very high conc. Of Na, K, Fe, Mn, and Al contents than the rice

21. DIETARY RISK EXPOSURE

22. CALCULATION OF DIETARY EXPOSURE • Concentration of elements in fresh weight of food items calculated • Individual food item intake by poor and non-poor households in Dhaka city obtained from HIES, 2010 Dietary Exposure = Concentration of elements x amount of food consumed • Compared with the MPL for heavy metals and RDI for minerals and trace elements

23. CALCIUM INTAKE Poor: 297-583 mg d-1; Non-poor: 196-888 mg d-1 100% poor below RDI 94% non-poor below RDI

24. SODIUM INTAKE Poor: 172-471 mg d-1; Non-poor: 131-542 mg d-1 100% poor & non-poor below RDI for both Na

25. POTASSIUM INTAKE Poor: 582-1657 mg d-1; Non-poor: 899-3299 mg d-1

26. COPPER INTAKE Poor: 0.6-2.5 mg d-1; Non-poor: 0.8-4.0 mg d-1 Poor HHs suffer more Cu deficiency than non-poor HHs

27. ZINC INTAKE Poor: 3.1-14.3 mg d-1 Non-poor: 4.4-16.7 mg d-1

28. COBALT INTAKE Poor: 3.3-85.1 mg d-1 Non-poor: 15.0-345.9 mg d-1 32% poor above RDI 99% non-poor above RDI

29. NICKEL & SELENIUM INTAKE Ni Se Poor Poor: 100% below RDI Non-poor: 27% Above RDI No RDI

30. ALUMINIUM INTAKE Poor: 0.37-12.44 mg d-1 Non-poor: 3.0-34.2 mg d-1 PTDI of Al: 8.6 mg/60 body wt/day 92% poor and 83% non-poor are at risk of Al contamination

31. CADMIUM INTAKE Poor: 17.5-204.3 µg d-1; Non-poor: 5.6-113.4 µg d-1 MPL: 50 micro g/60 kg bw/day 94% poor and 78% non-poor are at risk of Cd contamination

32. ARSENIC AND LEAD INTAKE ARSENIC LEAD ANY CONCENTRATION IS HARMFUL

33. INTAKE OF ANTIMONY, LITHIUM AND MERCURY ALL ARE SAFE

34. CONCLUSIONS • Poor household males are noted to have more mineral (Ca, Mg and K) and trace element (Fe, Cu, Zn, Co and Se) deficiency compared to non-poor household males • Intake of Mn and Mo is noted to be higher than the Recommended Daily Intake for both poor and non-poor households. • About 94% males from poor households and 78% males from non-poor households have higher dietary risk exposure to Cd above PTMI, and are exposed to Cd contamination.

35. Antimony, mercury and lithium intake through foods by males from both poor and non-poor households are below PMTI. • Both poor and non-poor households have high intake of arsenic and lead from different foods. FAO (2010) has withdrawn the PTWA of As and Pb. Therefore, all the males of poor and non-poor households have high dietary risk exposure to As and Pb contamination.

36. POLICY IMPLICATION • An in-depth study is further needed to identify the hot spots of heavy metals contaminated areas near to and away from Dhaka city • Cultivation of rice with arsenic free water (DTW or surface water) to reduce the arsenic in food chain. • Need to screen and develop rice varieties for lower uptake of arsenic and cadmium by grains in order to decrease the dietary risk exposure to arsenic and cadmium intake by the population • Strong monitoring is needed to ensure the treatment of industrial effluents before its disposal and use of phosphatic fertilizers with very less amount of Cd and use the Pb free fossil fuels.

37. Decreased consumption of rice and increased consumption of vegetables might keep balance/reduce the dietary risk exposure to arsenic, lead and cadmium • Increased consumption of livestock and fish foods will help decrease the selenium deficiency in the population • Need to build baseline data on the content and extent of contamination of heavy metals following up from this investigation.

38. POLICY IMPLICATION High variation in minerals, trace elements and heavy metals in foods among three markets depends on the places of production Arsenic gets entered into human body through As-contaminated STW irrigation water via plant uptake Entry of other heavy metals into food chain comes from industrial discharge, combustion of fossil fuels, roadside dust, fertilizers and sewage sludge. The industrial effluents should be treated before draining into the water course. Exposure to heavy metals by Bangladeshi diet