Lead in children's food: Causes, health risks & prevention in Bangladesh

What is lead contamination in food?

Lead contamination occurs when food contains lead, a toxic heavy metal that can harm human health, especially in children. According to the World Health Organization's guidance on lead poisoning, there is no known safe level of lead exposure. Even small amounts can affect a child's brain development, learning and overall health.

Lead can enter food at different stages, from growing and harvesting to processing, packaging, and storage. Common sources include contaminated soil, polluted water, unsafe food colouring, and equipment containing lead.

What makes lead contamination particularly dangerous is that contaminated food often looks, smells, and tastes completely normal. Parents may unknowingly serve it to their children, making lead exposure difficult to detect without proper testing.

What causes lead contamination in children's food?

Lead rarely comes from one source. It can get into a child’s food from the farm, the factory, the kitchen or the tap, and a single meal may pick it up at more than one of these points. The sections below explain each source.

• Polluted soil and water: Crops grown in polluted soil or irrigated with contaminated water can absorb lead. Industrial waste and battery recycling are common sources of this pollution. Vegetables, rice and other crops can be affected, depending on how heavily the land is polluted.
• Unsafe food processing: Lead can enter food during processing if the equipment, ingredients or workplace are contaminated. Dirty grinding machines and poor quality control raise the risk. This is why testing matters most for products made for babies and young children.
• Lead-contaminated spices and food colouring: Turmeric and chilli powder may contain harmful colouring agents if processed unsafely. A 2019 study found that some turmeric producers in Bangladesh used toxic lead chromate to brighten the colour. However, a 2023 follow-up study reported that contamination in turmeric samples from a major wholesale market dropped from 47% to 0% following food safety interventions. Parents should buy spices from reliable sources.
• Unsafe cookware and storage: Cheap metal pots and lead-glazed ceramic dishes can release lead into food. The risk depends on the material and how well it was made. Acidic foods, such as tomatoes and tamarind, can draw out more lead.
• Contaminated drinking water: Lead can enter water from polluted sources or from pipes that contain lead. Water is used to make baby formula, porridge and rice, so its safety matters. Boiling does not remove lead from water.

Why are children hurt more than adults?

The same amount of lead does far more damage to a child than to an adult. A child’s body is small and still growing, and it takes in lead more easily. Even a tiny amount can leave lasting harm. The points below explain why.

• Their brains are still growing. Lead can disturb the fast growth of the brain and nervous system in the early years.
• They absorb more lead. Young children take in much more of the lead they swallow than adults do.
• They are small. The same amount of lead is a bigger dose for a small body.
• They put things in their mouths. They suck their hands and toys, and they play on floors where dust collects.
• Poor nutrition makes it worse. Children who lack iron or calcium absorb more lead.
• They depend on adults. They do not know what is unsafe, and they cannot choose their own food, water or home.
• Exposure can start before birth. Lead in a mother’s body can reach the baby.

Harmful effects of lead contamination on children's health

Lead can harm almost every part of a child’s body, but the brain is hit hardest. Some effects show up quickly, while others appear months or years later and may never fully go away. Many signs look like ordinary childhood illness, so lead is easy to miss. The points below explain the main effects.

• Brain development and learning: Lead harms the developing brain. It is linked to lower thinking ability, learning problems, poor attention and changes in behaviour. Some of this damage can last even after the source of lead is removed.
• Slow growth and development: Long-term exposure can slow a child’s physical growth. Some children reach milestones such as walking or talking later than expected. A doctor should check these signs, because they can have other causes too.
• Anaemia: Lead interferes with the making of haemoglobin, the part of blood that carries oxygen. This can cause anaemia, mostly when exposure is high. An anaemic child may look tired, weak and less active. Anaemia alone does not prove lead poisoning.
• Stomach problems: Lead exposure can also affect a child's digestive system. Some children experience constipation, stomach pain, poor appetite, nausea or vomiting. These symptoms have many possible causes, so they do not necessarily indicate lead poisoning.
• Kidney and nerve damage: High or long-term exposure can damage the kidneys and nerves. Severe poisoning can cause seizures or loss of consciousness. These are emergencies, and the child needs to go to the hospital immediately.

Signs and symptoms of lead poisoning in children

One of the biggest challenges is that many children with elevated blood lead levels have no obvious symptoms. When symptoms occur, they may include:

• Unexplained abdominal discomfort or constipation
• Poor appetite
• Irritability or unusual behavioural changes
• Tiredness and weakness
• Difficulty concentrating or learning
• Developmental concerns

Note: Many children with lead exposure show no obvious symptoms. A blood lead test is the most reliable way to measure lead exposure. A pediatrician can review the result and determine whether further testing or follow-up is necessary.

How to prevent lead exposure from children's food

You cannot see or taste lead, so prevention has to come before the meal, not after. A few simple habits can lower your child’s risk a great deal: choose food and water carefully, cook and store it safely, and keep your child well fed. The steps below show how.

• Buy from trusted sources: Buy baby food, spices and grains from known makers and sellers. Check labels, packaging and any recall notices.
• Keep food preparation clean: Wash fruits and vegetables under clean running water, and keep cooking areas and utensils clean. Washing removes surface dirt, but it cannot remove lead that is already inside the food.
• Use safe pots and containers: Use food-grade stainless steel or glass. Avoid damaged or cheap metal pots and lead-glazed pottery, especially for children’s meals.
• Make sure drinking water is safe: Use water from a source you know is safe. If you suspect lead, get the water tested and use a lead-removing filter or another safe source. Boiling kills germs but does not remove lead.
• Feed a balanced diet: Good nutrition helps the body absorb less lead. Include:
  
  • Iron: meat, fish, eggs, and lentils
  • Calcium: milk and yogurt
  • Vitamin C: guava, oranges, and tomatoes
• Follow food safety news: Avoid any product that authorities have named as contaminated.

When should you take your child to a pediatrician?

See a doctor if you think your child has eaten or drunk something that may contain lead, even if the child looks well. Lead often causes no clear signs at first, and only a blood test can confirm it. Go to a child specialist immediately if your child has seizures, severe vomiting, extreme sleepiness or confusion.

If your child has persistent constipation, poor appetite or recurring stomach problems, a pediatric gastroenterology consultation can help assess digestive causes. If lead exposure is suspected, the pediatrician may also recommend a blood lead test and further assessment.

Also book a visit if your child:

• has unexplained tummy pain, constipation or vomiting,
• looks pale or tires easily,
• is slow to learn, hard to focus or unusually irritable,
• eats soil, paint chips or other non-food items, or
• lives near a battery workshop, factory or old painted building.

Concerned about Lead exposure? Consult a child specialist in Dhaka

If your child has unexplained stomach pain, poor appetite, constipation or developmental concerns, a proper medical assessment can help identify possible causes. If you suspect exposure to lead-contaminated food or water, don't wait for symptoms to appear before seeking advice. Prof. Dr. Salahuddin Mahmud is a pediatric gastroenterology, hepatology and nutrition specialist with over 23 years of experience.

Consult him for your child's digestive, nutritional and related health concerns. Hearing about toxic metals in food is frightening, but your child doesn’t need to go through this unprotected. A child’s diet, growth and digestive health are closely linked, and early advice makes a real difference.

• MBBS (Dhaka) and MD in Pediatrics from Bangabandhu Sheikh Mujib Medical University.
• Fellow in Pediatric Nutrition – Boston University, USA.
• Clinical Fellowship in Pediatric Gastroenterology & Hepatology – Birmingham Children's Hospital, UK.
• Clinical Fellowship in Pediatric Gastroenterology & Hepatology – Sanjay Gandhi Postgraduate Institute, Lucknow, India.
• Pediatric Endoscopy Fellowships – Sheffield Children's Hospital, UK, and Indraprastha Apollo Hospital, India.
• Research and publications – Published scientific papers in national and international journals and presented research on childhood hepatitis A in Melbourne, Australia.