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Test for lead
Lead in food: A hidden health threat
According to the Environmental Defense Fund, it is never safe to consume lead, even at the lowest levels. Exposure to heavy metals like lead has been linked to a whole host of problems, especially for young children.
Lead was detected in 20% of baby food samples compared to 14% for other foods.
Eight types of baby foods had detectable lead in more than 40% of samples.
Baby food versions of apple and grape juices and carrots had more samples with detectable lead than the regular versions.
Testing of Maggi at the Central Food Technological Research Institute (CFTRI), Mysuru, found high lead content.
Detection of lead was performed by students of Seth Anandram Jaipuria School, Lucknow campus. Lead was detected by adding potassium iodide and potassium chromate to the washed filtrate (obtained by washing precipitate of group I) which gives the yellow precipitate.
Test for chloride ion
Chloride is found in table salt or sea salt as sodium chloride. It is also found in many vegetables. Foods with higher amounts of chloride include seaweed, rye, tomatoes, lettuce, celery, and olives. Chloride, combined with potassium, is also found in many foods. Some water sample also contains chloride ion.
Test for chloride ion was performed by students, where they did Chromyl chloride test with careful attitude. Students experienced the red vapours of chromyl chloride which on passing in sodium hydroxide solution turns the solution yellow. On adding lead acetate, chloride ions gets precipitated in the same solution.