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1394. A new use for polyethylene
PROCESSING AND PACKAGING CONTAMINANTS
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One o f six rabbits given repeated doses of 0.5 LDso of I displayed paralysis of the hind legs which was still manifest 3 wk after treatment. Injections of I into mice caused severe depression of the central nervous system and respiratory paralysis; II was less active and lII and IV much less still in this respect. 1394. A new use for polyethylene Chandler, P. T., Kesler, E. M. & Jones, G. M. (1966). Excretion of polyethylene by dairy calves. J. Anita. Sci. 25, 64. One of the many uses of polyethylene (I) is as a food-packaging material. Following oral administration it has now been shown to be quantitatively excreted in the faeces of dairy calves. Diets containing 5 % I, supplemented or not with 10% lard, were fed to calves for 10 days and the faecal excretion was followed. With both diets, it took at least 7 days for the excretion of I in the faeces to equal the daily intake, although the rate of excretion was more rapid on the lard-free diet. This finding, together with the ease of estimation of I, suggests that I could be a useful reference standard for measuring digestion coefficients. [The lack of gastro-intestinal absorption of polyethylene coupled with the fact that only trace amounts are likely to find their way in food attests to its innocuity in food-packaging applications.] 1395. Chromium binds with serum albumin Pierce, J. O. & Stemmer, K. L. (1966). Toxicity of alloys of ferrochromium. II. Interactions of chromium 3 with proteins of human serum. Archs envir. Hlth 12, 190. In considering the reduction of hexavalent (Cr v~) to trivalent (Cr m) chromium as a preliminary to the induction of sensitivity (Cited in F.C.T. 1966, 4, 89), w~ have seen that yglobulin has some reducing activity. The present study shows that once in the bloodstream, Cr m can bind with human serum albumin near its isoelectric point. In experiments in which serum proteins x~ere separated from Cr m solutions by a semipermeable membrane, the number of moles of Cr m bound to each mole of protein increased in linear relationship to the amount of Cr m available. Temperature was not critical, but a decrease in pH (from 7-35 to 4.85) reduced the degree of binding which occurred. Esterification of the albumin prevented Cr m binding, which suggests that the carboxyl groups of the protein are responsible for the effect. The formation of large protein-metal complexes such as these may account for some immunotoxicological phenomena. The fl- and y-globulins o f human serum seem to have a much lower order of reactivity with Cr m, but a-globulin is highly reactive.
1396. Polyhydric alcohols as potential foods Stoewsand, G. S., Dymsza, H. A., Swift, S. M., Mehlman, M. A. & Therriault, D. G. (1966). Effect of feeding polyhydric alcohols on tissue lipids and the resistance o f rats to extreme cold. J. Nutr. 89, 414 Many compounds which can be synthesized chemically or derived from natural products such as petroleum and algae are potentially useful as foods. The possibility has now been examined of using propylene glycol (I), 1,3-butanediol (II) and glycerol (Ill) as sources of dietary energy. Diets containing 30 3/fat supplemented or not with 20 % I, II or III to substitute isocalorically for carbohydrates were fed to rats maintained at 25 or 5° for 4 wk. Growth retardation with I at both 25 and 5° and with II at 25 ° was due to decreased food intake and not to altered food efficiency. In addition the epididymal fat pad was considerably smaller in rats fed I or I]. For some unaccountable reason, 1 also caused a very marked increase in liver lipid at both environmental temperatures and in liver cholesterol too at 25 °. Rats on I or II maintained at 25 ° for 5 wk before being subjected to extreme cold ( - 2 0 °) exhibited half the
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One o f six rabbits given repeated doses of 0.5 LDso of I displayed paralysis of the hind legs which was still manifest 3 wk after treatment. Injections of I into mice caused severe depression of the central nervous system and respiratory paralysis; II was less active and lII and IV much less still in this respect. 1394. A new use for polyethylene Chandler, P. T., Kesler, E. M. & Jones, G. M. (1966). Excretion of polyethylene by dairy calves. J. Anita. Sci. 25, 64. One of the many uses of polyethylene (I) is as a food-packaging material. Following oral administration it has now been shown to be quantitatively excreted in the faeces of dairy calves. Diets containing 5 % I, supplemented or not with 10% lard, were fed to calves for 10 days and the faecal excretion was followed. With both diets, it took at least 7 days for the excretion of I in the faeces to equal the daily intake, although the rate of excretion was more rapid on the lard-free diet. This finding, together with the ease of estimation of I, suggests that I could be a useful reference standard for measuring digestion coefficients. [The lack of gastro-intestinal absorption of polyethylene coupled with the fact that only trace amounts are likely to find their way in food attests to its innocuity in food-packaging applications.] 1395. Chromium binds with serum albumin Pierce, J. O. & Stemmer, K. L. (1966). Toxicity of alloys of ferrochromium. II. Interactions of chromium 3 with proteins of human serum. Archs envir. Hlth 12, 190. In considering the reduction of hexavalent (Cr v~) to trivalent (Cr m) chromium as a preliminary to the induction of sensitivity (Cited in F.C.T. 1966, 4, 89), w~ have seen that yglobulin has some reducing activity. The present study shows that once in the bloodstream, Cr m can bind with human serum albumin near its isoelectric point. In experiments in which serum proteins x~ere separated from Cr m solutions by a semipermeable membrane, the number of moles of Cr m bound to each mole of protein increased in linear relationship to the amount of Cr m available. Temperature was not critical, but a decrease in pH (from 7-35 to 4.85) reduced the degree of binding which occurred. Esterification of the albumin prevented Cr m binding, which suggests that the carboxyl groups of the protein are responsible for the effect. The formation of large protein-metal complexes such as these may account for some immunotoxicological phenomena. The fl- and y-globulins o f human serum seem to have a much lower order of reactivity with Cr m, but a-globulin is highly reactive.
1396. Polyhydric alcohols as potential foods Stoewsand, G. S., Dymsza, H. A., Swift, S. M., Mehlman, M. A. & Therriault, D. G. (1966). Effect of feeding polyhydric alcohols on tissue lipids and the resistance o f rats to extreme cold. J. Nutr. 89, 414 Many compounds which can be synthesized chemically or derived from natural products such as petroleum and algae are potentially useful as foods. The possibility has now been examined of using propylene glycol (I), 1,3-butanediol (II) and glycerol (Ill) as sources of dietary energy. Diets containing 30 3/fat supplemented or not with 20 % I, II or III to substitute isocalorically for carbohydrates were fed to rats maintained at 25 or 5° for 4 wk. Growth retardation with I at both 25 and 5° and with II at 25 ° was due to decreased food intake and not to altered food efficiency. In addition the epididymal fat pad was considerably smaller in rats fed I or I]. For some unaccountable reason, 1 also caused a very marked increase in liver lipid at both environmental temperatures and in liver cholesterol too at 25 °. Rats on I or II maintained at 25 ° for 5 wk before being subjected to extreme cold ( - 2 0 °) exhibited half the