Dietary ingestion

Susceptibility to lead toxicity is influenced by dietary levels of calcium, iron, phosphorus, vitamins A and D, dietary protein, and alcohol (Calabrese 1978). Low dietary ingestion of calcium or iron increased the predisposition to lead toxicity in animals (Barton et al. 1978a Carpenter 1982 Hashmi et al. 1989a Six and Goyer 1972 Waxman and Rabinowitz 1966). Iron deficiency combined with lead exposure acts synergistically to impair heme synthesis and cell metabolism (Waxman and Rabinowitz 1966). 

Routes of administration other than dietary ingestion should not be discounted. Livestock found dead near a cyanide disposal site had been drinking surface water runoff from the area that contained up to 365 mg HCN/L (USEPA 1980). The use of cyanide fumigant powder formulations may be... 

Goldman M, Doering GJ, Neilson RG Effect of dietary ingestion of oxalic acid on growth and reproduction in male and female Long-Evans rats. Res Commun Chem Pathol Pharmacol 18 369-372, 1977... 

Fotsis T, Pepper M, Adlercreutz H et al. Genistein, a dietary ingested isoflavonoid, inhibits cell proliferation and in vitro angiogenesis. J. Nutr. 125, 790S-797S, 1995. 

Most studies show that bioaccumulation predominantly results from chemical absorption directly from water via the respiratory surface (e.g., gills and/or skin) of the organism (i.e., bioconcentration) and from diet via the gastro-intestinal tract (i.e., biomagnification). Exceptions occur e.g., phytoplankton species generally do not absorb chemical by dietary ingestion, organisms obtain chemical via maternal transfer, and some species contain unique mechanisms for chemical uptake and elimination. 

Route of exposure is defined as the portal of entry to the body. Pathway is defined as the course that the contaminant takes from its source to the exposure medium, and then to the portal of entry. For a given source, exposure media and exposure routes can define the pathways. Depending upon the life stage of the child, exposure media can include amniotic fluid, breast milk, air, water, soil/dust/ sediments, food, and objects/surfaces. Exposure routes include transplacental transfer, inhalation, ingestion, dermal absorption, and indirect (non-dietary) ingestion. 

Freshwater fish and shellfish consumption rate (dietary ingestion factor) 6.0 g/day Marine fish and shellfish consumption rate (dietary ingestion factor) 14.1 g/day... 

Hubal, C.E., K. Thomas, J. Quackenboss, E. Furtaw, and L. Sheldon (1999). Dermal and Non-Dietary Ingestion Workshop, EPA 600/R-99/039, United States Environmental Protection Agency, Research Triangle Park, NC, USA. 

The Environmental Protection Agency has established guidelines for toxicological dose and endpoints for acetamiprid. Using the no-observed-adverse-effect level (NOAEL) and uncertainty factor (UF), the reference dose (RfD) can be calculated. For acute dietary ingestion for infants and children, NOAEL = 10 mg kg RfD = 0.10 mg kg day Chronic dietary expo-... 

Schlekat, C.E., Decko, A.W. and Chandler, G.T. (2000) Bioavailability of particle-associated silver, cadmium, and zinc to the estuarine amphipod, Leptocheirus plumulosus through dietary ingestion. Limnol. Oceanogr., 45, 11-21. 

Abstract Indoor contamination is one source of exposure to toxic pollutants and has been classified as a high environmental risk. Epidemiological research linked health effects including childhood leukemia and neuroblastoma to the indoor occurrence of pesticides. Pesticides in indoor environments contribute to human exposure via inhalation, non dietary ingestion and dermal contact. Sources for pesticides indoors are direct applications, pesticides used in varnishes, colors, adhesives, etc., or in finishing textiles, leather, carpets, etc., and pesticides brought in from outdoors. Results for pesticides in indoor environments from different countries and obtained under different conditions are compiled in this chapter. They are discussed by applying two approaches (1) the comparison with reference values... 

Burse VW, Kimbrough RD, Villanueva EC, et al. 1974. Polychlorinated biphenyls Storage, distribution, excretion, and recovery Liver morphology after prolonged dietary ingestion. Arch Environ Health 29 301-307. 

Radiocesium isotopes from the Chernobyl accident transferred easily to grazing farm animals. Both Cs and Cs were rapidly distributed throughout the soft tissues of animals after dietary ingestion and were most highly concentrated in muscle. Radiocesium activity in milk and flesh of Norwegian sheep and goats, for example, increased three- to fivefold 2 years after the accident and coincided with an abundant growth and availability... 

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