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

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

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

Major Routes of Heavy Metal Contamination: Example arsenic Fish

OBJECTIVES i)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) ii)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

METHODOLOGY

MarketCategory by incomeCategory by Kcal intake 1. GulshanUpper income groupNon-poor (>2122 Kcal/day/person) 2. KawranbazarMiddle income group 3. HazaribaghLow income groupPoor (<2122 Kcal/day/person) 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)

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

CHEMICAL ANALYSIS Digestion Food samples were digested with Ultrapure grade HNO 3 and H 2 O 2 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)

RESULTS

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

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

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

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

ZINC CONC. IN VEGETABLES

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

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

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

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

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

DIETARY RISK EXPOSURE

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

CALCIUM INTAKE SourcePoorNon-poor Cereals 27.3 Pulses 5.2 Fish Meat Vegetables Milk, dairy 10.6 Sweetmeat 2.3 Fruits Sug. molas % poor below RDI 94% non-poor below RDI Poor: mg d -1 ; Non-poor: mg d -1

SODIUM INTAKE 100% poor & non-poor below RDI for both Na Food groupPoorNon-poor Cereals Pulses Fish Eggs0.1 Meat Vegetables Milk & dairy Fruits0.6 Poor: mg d -1 ; Non-poor: mg d -1

POTASSIUM INTAKE Food groupPoorNon-poor Cereals Pulses Fish Meat Vegetables Milk & dairy Fruits Poor: mg d -1 ; Non-poor: mg d -1

COPPER INTAKE Poor HHs suffer more Cu deficiency than non-poor HHs Poor: mg d -1 ; Non-poor: mg d -1 Food groupPoorNon-poor Cereals Pulses Fish Eggs0.07 Meat Vegetables Milk & dairy Fruits

ZINC INTAKE Poor: mg d -1 Non-poor: mg d -1 Food groupPoorNon-poor Cereals Pulses Fish Eggs Meat Vegetables Sweetmeat Fruits

COBALT INTAKE 32% poor above RDI 99% non-poor above RDI Food groupPoorNon-poor Cereals Pulses Fish Meat Vegetables Sweetmea t Fruits Poor: mg d -1 Non-poor: mg d -1

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

ALUMINIUM INTAKE 92% poor and 83% non-poor are at risk of Al contamination Food groupsPoorNon-poor Cereals Pulses Fish Vegetables Sweetmeat Oil & fats Fruits Sugar,molasses Poor: mg d -1 Non-poor: mg d -1 PTDI of Al: 8.6 mg/60 body wt/day

CADMIUM INTAKE 94% poor and 78% non-poor are at risk of Cd contamination Poor: µg d-1; Non-poor: µg d-1 Food groupPoorNon-poor Cereals Pulses0.00 Fish Eggs0.00 Meat0.16 Vegetables Fruits0.08 MPL: 50 micro g/60 kg bw/day

ARSENIC AND LEAD INTAKE ARSENICLEAD ANY CONCENTRATION IS HARMFUL

INTAKE OF ANTIMONY, LITHIUM AND MERCURY ElementPoorNon-poor Antimony (µg d -1 ) Lithium (µg d -1 ) Mercury (µg d -1 ) ALL ARE SAFE

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.

 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.

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.

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.

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