W.H. Brown

Secretion of DDT in milk by fresh cows

Environmental contamination of animal feed by pesticides applied onto nearby crops is considered to be the major source of pesticide residues found in milk. However, examination of the pesticide input from these sources frequently does not account for the level of pesticide residue found in the corresponding milk. Attempts to explain the discrepancy between the amount of pesticide residue found in milk and the amount which one can predict should be found based on many feeding studies (i, 2, 3, 4) has led many persons to suggest that there may be a relationship between these unexplainably high pesticide residues in milk and the stage of lactation in the cow, i.e. that cows which have just come fresh secrete more pesticide in their milk fat than during later stages of lactation. The rationale which

Rate of Transfer of DDT from the Blood Compartment

ConclusionsThe rate of decline of DDT from the blood has been shown to be quite rapid and recovery of pesticide from the blood has been related to the recovery of lipid from the blood.

The sub-cellullar partition and metabolism of oprally administered 1,1,1-Trichloro-2, 2-bis (p-chlorophenyl) ethane by rat liver cells

Abstract Uptake of orally administered DDT by rat liver cells has displayed the following characteristics: 1. The pesticide was not exclusively segregated from any one cell fraction. 2. Pesticide was depleted with time from all fractions. 3. A redistribution of pesticide occurred with time. A passive DDT distribution either occurs at some point in time or at low levels of exposure. 4. Non-lipid binding of pesticide appeared to occur. 5. Liver cells appeared to be detoxifying DDT to DDE and DDD by 16 hr post treatment.

Metabolism of toxaphene by the isolated perfused bovine liver

The metabolic fate of toxaphene was studied by perfusion experiments with isolated bovine livers. Metabolic patterns were elucidated by examining toxaphene components and toxaphene derived products in perfusate and liver tissue using gas liquid chromatography/electron capture detection. These patterns revealed that the bovine liver is capable of a very rapid uptake of toxaphene components from the blood followed by a rapid rate of dechlorination. The liver also accumulates partially dechlorinated products with a subsequentslow rate of further degradation.

Grapefruit seed oil sterols

Grapefruit seed oil sterols separated from other lipids by Florisil column chromatography were characterized by gas liquid chromatography. The presence of stigmasterol, campesterol and β-sitosterol is indicated. Expressed in terms of peak area, the three sterols are present in proportions of 2.5%, 7.4% and 90.1% of the total, respectively.