Lead in food

Ellen G, Van Loon JW. 1990. Determination of cadmium and lead in foods by graphite furnace atomic absorption spectrometry with Zeeman background correction Test with certified reference materials. Food Addit Contam 7 265-273. 

Shea EE. 1996. Lead regulation handbook. Rockville, MD Government Institutes, 240 pages. Sherlock JC. 1987. Lead in food and the diet. Environmental Geochemistry and Health 9 43-47. 

AOAC Method 982.23 Cadmium and lead in food (not for fats and oils) (1988)... 

Food contamination may result from transmission of lead from glaze, enamel, or tinning on kitchen dishes, or from the lead on surfaces of containers or pipes used for storage, processing and transportation of food products. The occurrence of lead in food can also result from environmental contamination, as plants and animals may assimilate lead during growth and incorporate it into their tissues. The level of lead found in plant tissues is proportional to its concentration in the environment, and in cases of animals, the feed and water supplies also play important roles (Vreman et al., 1988 McLaughlin et ah, 1999 Sedki et ah, 2003). 

Young children are especially susceptible to the effects of environmental lead, first because their bodies accumulate lead more readily than do those of adults and, second, because they appear to be more vulnerable to certain of the biological effects of lead. In 1988 the US Public Health Service estimated that, in the United States alone, 12 million children were exposed to leaded paint, 5.6 million to leaded gasoline, 5.9-11 million to dusts and soils containing excessive lead, 10.4 million to lead in water (in part because of lead in pipe solders) and 1.0 million to lead in food. The Public Health Service also... 

There has been a huge amount of analytical work on metals such as lead in food. Indeed a large part of the periodic table has been covered. Early work on metals identified that analytical quality assurance is a key tool in the surveillance of food for chemical contaminants. It also led to the development of toxicological standards which can be used to define whether or not surveillance results show there is a hazard to consumer health. Both of these types of approaches are now standard in the best surveillance programmes, whether they are on contaminants or additives in food. 

The exposure to lead in food by the general population in the UK is well within international tolerable limits. Results from the TDS indicate that during the period 1976 to 1997 the dietary exposures over the whole population fell from 0.11 to 0.026 mg per person/day (Table 7.1).6 This excludes any contribution from drinking water, which is likely to be higher in areas with soft water. The PTWI recommended by JECFA is 0.025 mg/kg bodyweight, equivalent to 0.21 mg/day for a 60 kg adult. The dietary exposures for mean and 97.5th percentile consumers in 1997 were 0.024 mg/day and 0.043 mg/day respectively, well below the PTWI. These dietary exposures to lead in the UK are similar to those in Canada (0.024 mg/day),7 The Netherlands (0.01 to 0.032 mg/day),8 and the USA (0.015 mg/day).9... 

Lead concentrations in most foods in the 1997 UK TDS were generally low,10 with all but a few samples containing lead at levels below the limits defined in the Lead in Food Regulations 1979, as amended.11 This includes a general limit of 1 mg/kg and limits for specific foods as defined in Schedules to the Regulations. 

Sherlock JC. 1987. Lead in food and the diet. Environmental Geochemistry and Health 9 43-47. 

G. Capar, A. Subjoc, Defining a lowest level of reliable measurement for lead in foods, J. Assoc. Off. Anal. Chem., 65 (1982), 1025-1029. 

J. Marrero, S. Perez-Arisnabarreta, P. Smichowski, Comparison of effects of four acid oxidant mixtures in the determination of lead in food and beverages by hydride generation - ICP - OES, Atom Spectrosc., 24 (2002), 133-141. 

Great Britain Ministry of Agriculture, Fisheries and Food, Survey of Lead in Food, Her Majesty s Stationery Office, London, 1972. 

Official Methods of Analysis of AOAC International, 17th edn. Rev 1, AOAC International, Gaithersburg, MD, USA, Official Method 972.25. Lead in Food - Atomic Absorption Spectrophotometric Method (2002)... 

The Pure Food Law of 1906 was amended in 1938 to include pesticides on foods, primarily the arsenicals, such as lead arsenate and Paris green. It also required the adding of color to white insecticides, including sodium fluoride and lead arsenate, to prevent their accidental use as flour or other look-alike cooking materials. This was the first federal effort toward protecting the consumer from pesticide-contaminated food by providing tolerances for pesticide residues, namely arsenic and lead, in foods where these materials were necessary for the production of a food supply. 

Nabrzyski, M. and Gajewska, R., Determination of mercury, cadmium and lead in food, Roczniki PZFl, 35, 1, 1984 (in Polish). 

MAFF. Lead in Food Third Supplementary Report on Lead. Food Surveillance Paper No. 27, HMSO, London, 1989, pp. 1-66. 

The concentrations of lead in foods are typically less than 100 p.g/kg fresh weight. Foods with high surface areas (such as spinach) also tend to have higher concentrations of lead due to atmospheric deposition. Canned foods (especially if the food is at a low pH) often have much higher concentrations of lead than foods packed in another manner (OECD, 1993). 

The lead concentrations found in C. virginica from these coastal lagoons by several authors are presented in Table 17. All the authors compared their results with the US-FDA limit for lead in food of 0.2 mg/kg (1971). As can be seen, except for those from Villanueva, all the results exceeded this limit therefore, these oysters should not have been acceptable for human consumption. However, these results have not been taken into consideration by the responsible authorities and no regulations or controls for the sale of this type of food have been established up to this date. 

PROTECTING YOUR FAMILY FROM LEAD IN FOOD... 

There is a long history of human exposure to abnormally elevated levels of lead in food and drink due to practices such as cooking in lead-lined or lead-glazed pots and the supply of water through lead pipes [1]. Also, some communities living in areas of lead mineralization are exposed to higher levels of lead... 

People are exposed to lead tlirough breathing lead-polluted air and through the ingestion of lead in food and drink. The relative importance of each particular route of exposure is a matter of some uncertainty, and does of course vary considerably between individuals dependent upon their places of residence and work, and their dietary habits. Lead has always been present at low levels in food and drink due to the natural occurrence of the metal in rocks and soils. Deposition of lead aerosol may enhance the levels of lead in foodstuffs and water, but the magnitude of this is difficult to quantify. 

People are simulaneously exposed in varying degrees to lead in food, drink and air, as well as a number of other sources (Fig. 7.1). There is a continuing debate as to the significance of each of these particular pathways, which is unlikely to be readily resolved, due to the diversity of sources of exposure and their lead concentrations, as well as the varied nature of the individual s metabolic response to the lead. It is, nevertheless, important to attempt to estimate the relative significance of the difference pathways, in order to allow effective implementation of measures designed to limit exposure. 

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