Fatty acid composition of liver lipids in rats fed brominated fatty acids.

Feeding rats diets containing brominated corn oil or di- or tetrabromostearate as the monoglyceride produced changes in fatty acid composition of liver lipids. Those changes associated with the feeding of brominated corn oil or tetrabromostearate could be explained by the accumulation of triglyceride, and the changes associated with the feeding of dibromostearate could result from the proliferation of a membrane system. A unique response to the feeding of diets containing brominated corn oil is an increase in the level of gamma-linolenic acid.

Bromine levels in tissue lipids of rats fed brominated fatty acids.

Rats have been fed diets containing either 0.8% brominated corn oil or 0.5% of the ethyl ester of 9,10-dibromostearate or 9,10,12,13-tetrabromostearate. The brominated compounds were incorporated into semisynthetic diets and animals were observed after feeding periods of 5 days to 3 months. With the exception of adipose tissues, the highest concentration of lipid-bound bromine was observed after 5 days on the experimental diets. It was also observed that feeding of the dibromostearate resulted in the highest levels of lipid-bound bromine in heart, whereas the tetrabromostearate tended to result in higher levels of lipid-bound bromine in liver. Brominated corn oil produced more substantial changes than the brominated fatty acid esters, inducing fatty livers and enlarged yellow hearts. Microscopic examination indicated myocardial degeneration and occasional early necrosis.

Toxicology of brominated fatty acids: metabolite concentration and heart and liver changes.

Rats were fed for 35 days diets containing 2% of either brominated corn oil (BCO), monoglyceride of dibromostearate (DBS), monoglyceride of tetrabromostearate (TBS) or a mixture of the two monoglycerides (BMG) which provided proportions of brominated acids comparable to that of the BCO. Hearts from all animals fed BCO were yellow colored and firm in texture. Myocardial cellular degeneration, mild to moderate edema and occasional small necrotic foci were observed. Hearts from animals fed DBS showed moderate edema and some slight necrosis. All diets produced an increase in lipid content of heart. Animals fed the experimental diets developed enlarged livers and showed elevated liver lipid content. The tetrabromostearate appeared to be the more active in producing these changes, in particular a severe intracellular fatty degeneration. Shorter-chain (C-16, C-14) metabolites of di- and tetrabromostearate were identified and the concentration of brominated fatty acids in heart, liver and adipose tissue determined and found to account for 80% of the bromine detected in these tissues by neutron activation analysis. TBS accumulated in liver while the highest concentration of DBS was observed in heart lipids. Although the concentrations of brominated acids in heart and liver lipids were comparable in rats fed BCO or BMG, BCO produced the more pronounced effects. This differential could be due to additional active components in BCO or to a variation in response associated with changes in the location of the fatty acid on the glycerol molecule.

Tissue fatty acid changes and tumor incidence in C3H mice ingesting cottonseed oil.

The incidence of spontaneous mammary tumors in C3H mice at 35 wk was higher in mice fed rations containing cottonseed oil than in mice fed fats of comparable fatty acid composition. The time to 50% (T50) incidence was also shorter in the first group. The fatty acid composition of tissue lipids from mice fed the cottonseed oil showed changes indicating the presence of cyclopropene fatty acids-higher levels of saturates and lower oleate/stearate and palmitoleate/palmitate ratios. A possible association between the development of a spontaneous mammary tumor in the C3H mouse and the presence of cyclopropene fatty acids in the cottonseed oil is indicated.

Cadmium absorption and tissue distribution in rats provided low concentrations of cadmium in food or drinking water.

Tissue Cd levels were determined 1, 2, 4, 8, and 12 wk after weanling rats were provided with food or water containing 1-1000 ng/g Cd as 109CdCl2. No differences in growth rate or organ weight were observed over the concentration range tested. Kidney accumulated the highest concentration of Cd, followed by liver with values one-third to one-fourth those found in the kidney. Liver, however, accounted for 35-55% of the total body burden, while kidney contained only 35-45%. Cd concentrations in the various tissues increased with time and the Cd concentration of the food or water. The percentage of the ingested dose absorbed in a given time was relatively constant over the tested Cd concentration range. However, for each metal concentration, the percent of Cd absorbed decreased with exposure time. Regression analysis established that female rats accumulated Cd at a higher rate and retained a greater percentage of the ingested Cd than did male rats and that tissue concentrations were higher in rats exposed to Cd in the water. The differences in tissue Cd levels are probably related to proportionally higher metal intake by females and to higher intake from water than food at equivalent concentrations. It is uncertain whether the greater retention of ingested Cd by females is due to more efficient absorption or a reduced rate of excretion of the metal.

Influence of dietary fatty acids on the incidence of mammary tumors in the C3H mouse.

Statistical techniques have been used to establish the extent to which the incidence of spontaneous mammary tumors in C3H mice could be associated with the levels of individual fatty acids in their diets. Eleven different fats and oils and nine mixtures of these fats and oils were selected so that the levels of the nine major fatty acids varied over a reasonable range and were not highly correlated with one another. Tumor incidence was observed in mice raised on diets containing 10% of these different fats. Multiple regressions have been calculated, expressing tumor incidence or time to tumor as a function of the levels of nine fatty acids, four saturated and five unsaturated, of the dietary lipids. Increased tumor incidence and decreased time to tumor were observed when increasing levels of linoleate (18:2) replaced the eight other fatty acids in the diet while the other polyunsaturated fatty acid, linolenate (18: 3), had little effect on tumor incidence. Four saturated fatty acids, laureate (12:0), myristate (14:0), palmitate (16:0), and stearate (18:0), were studied, with only the latter showing a significant effect. Increasing levels of stearate were associated with decreased tumor incidence and increased time to tumor. There was also a suggestion that erucic acid (22:1) reduced tumor incidence, but oleic acid (19:1) produced no significant effect.

Effect of chlorinated hydrocarbons on reproductive performance of adult White Leghorn male chickens.

Two experiments of 20 and 40 weeks duration were conducted to determine the effects of feeding dieldrin or PCB (Aroclor 1254) on the reproductive performance of adult White Leghorn males. Dieldrin at the levels used (0, 25, and 50 ppm) produced no significant changes in semen volume, semen concentration, fertility, and hatchability of fertile eggs. Mortality increased with increased levels of dieldrin and appeared related to duration of exposure to the pesticide. A significant reduction (P less than .05) in feed consumption was observed at the 25 ppm level. No significant differences in body weights were observed except shortly before death when marked reductions in both feed consumption and body weight were noted. PCB at the levels used (0, 10, 20, and 40 ppm) produced no differences in fertiluty, hatchability of fertile eggs, body weights, feed consumption, or mortality. However, over a period of 40 weeks, PCB significantly (P less than .05) reduced semen volume, semen concentrations, and testes weights,

Effect of DDE, DDT and calcium on the performance of adult Japanese quail (Coturnix coturnix japonica).

Two experiments were conducted to determine the effects of DDE, DDT and calcium on performance of quail. The quail received diets containing 0 or 100 p.p.m. of DDE for eight 28-day periods in Exp. 1 and 0, 100 or 300 p.p.m. of DDE or 100 p.p.m of DDT for six periods in Exp. 2. Diets containing either 0.5 or 3% calcium were used with each pesticide level. No differences in egg shell thickness, cracked eggs, egg production, feed consumption, egg weights, female body weights, fertility or hatchability were obtained from DDE or DDT up to 100 p.p.m. Three hundred p.p.m. of DDE did result in a decrease in female body weights and in fertility on the low calcium diet. Egg shell thickness, cracked eggs, egg production and hatchability were affected by the lower calcium level. Male body weights were adversely affected from 100 p.p.m. or more of DDE. Mortality increased as the level of DDE increased for females, while no effect was observed with DDT. Males appeared more sensitive to 100 p.p.m. of DDE in Exp. 1 and 300 p.p.m of DDE and 100 p.p.m. of DDT in Exp. 2. Livability and growth of chicks from hens receiving rations containing DDE AND DDT were unaffected by maternal treatment. In summary, DDE and DDT were without effect on egg shell quality or most other reproductive factors, but DDE at 300 p.p.m. did exert a detrimental effect on adult body weights, fertility and mortality.

Effect of dieldrin and calcium on the performance of adult Japanese quail (Coturnix coturnix japonica).

Two experiments were conducted to determine the effects of dieldrin and calcium on reproductive performance of quail. At 25% egg production the quail received diets containing 0,10 or 25 p.p.m. of dieldrin for 6, 28-day periods in experiment 1 and 0, 5, or 25 p.p.m. of dieldrin for 4, 28-day periods in experiment 2. Pesticide treatments were employed with diets containing 0.5% and 3.0% calcium. The results show that egg shell thickness, cracked eggs, egg production, feed consumption, egg weights, fertility, hatchability and body weights were not affected by dieldrin treatments. However, egg shell thickness, cracked eggs, egg production and hatchability were adversely affected by the lower calcium level. Female body weights were consistently heavier for the low calcium diet. Mortality increased in the presence of 10 and especially 25 p.p.m. of dieldrin. Livability of chicks from hens receiving rations with 10 and 25 p.p.m. of dieldrin was significantly lower than those fed no dieldrin. In summary, dieldrin was without effect on egg shell quality or other reproductive factors but did exert a detrimental effect on adult mortality and livability of progeny.

Binding of DDT to lecithin.

An interaction between DDT and lecithin is indicated by the reciprocal effects of each compound on the proton magnetic resonance spectrum of the other. The phosphoryl choline moiety of the lecithin and the benzylic proton of the DDT seem to be involved. The most pronounced response in the proton magnetic resonance spectrum of the lecithin produced by increasing concentration s of DDT was a change in the chemical shift of the resonance peak due to the protons of the choline methyl groups. Increasing concentrations of lecithin produced changes in the chemical shift of the resonance peaks of the benzylic proton and adjacent ring protons of the DDT. Equilibrium constant of 0.597 +/-0.015 molal(-1) was obtained for this interaction.