Instruct: Given a question, retrieve passages that answer the question.
Query: phosphorus
Background Many consumers avoid eating beans because they believe legume consumption will cause excessive intestinal gas or flatulence. An increasing body of research and the 2010 Dietary Guidelines for Americans supports the benefits of a plant-based diet, and legumes specifically, in the reduction of chronic disease risks. The purpose of the current research was to investigate the perception of increased flatulence and gastrointestinal discomfort among participants who consumed a ½ cup of beans daily for 8 or 12 weeks. Methods Participants in three studies to test the effects of beans on heart disease biomarkers completed the same weekly questionnaire to assess gastrointestinal discomfort issues such as increased flatulence, stool changes, and bloating. Studies 1 and 2 were randomized crossover trials. Participants consumed ½ cup of pinto beans, black-eyed peas, and canned carrots as control (n = 17) in Study 1 for three randomized 8-week phases. For Study 2, participants ate ½ cup baked beans or canned carrots as control (n = 29) for two randomized 8-week phases. Study 3 was a parallel arm trial with 40 subjects receiving ½ cup pinto beans and 40 consuming a control soup for 12 weeks. Changes in the frequency of perceived flatulence, stool characteristics, and bloating were the primary outcome measures. Chi-square distributions were examined for the presence or absence of symptoms and demographic characteristics to determine differences by gender, age, body mass index (BMI), and bean type. Results Less than 50% reported increased flatulence from eating pinto or baked beans during the first week of each trial, but only 19% had a flatulence increase with black-eyed peas. A small percentage (3-11%) reported increased flatulence across the three studies even on control diets without flatulence-producing components. Conclusions People's concerns about excessive flatulence from eating beans may be exaggerated. Public health nutritionists should address the potential for gastrointestinal discomfort when increasing fiber intake from beans with clients. It is important to recognize there is individual variation in response to different bean types.
The efficiencies of acidic solutions (radish, citric acid, ascorbic acid, acetic acid and hydrogen peroxide), neutral solutions (sodium chloride) and alkaline solution (sodium carbonate) as well as tap water in the elimination of organochlorine and organophosphorus pesticides from naturally contaminated potatoes were examined. The results indicated that acidic solutions were more effective than neutral and alkaline solutions in the elimination of the organochlorine compounds under investigation, Radish solutions eliminated pesticides completely, except o,p'-DDE (73.1% loss), followed by citric and ascorbic acid solutions. On the other hand, organophosphorus pesticides (pirimphos methyl, malathion and profenofos) were eliminated more by acidic, neutral and alkaline solutions than by organochlorines. The percentage of removal ranged from 98.5 to 100% for pirimphos methyl, 87.9 to 100% for malathion and 100% for profenofos.
This review explores the potential adverse impact of the increasing phosphorus content in the American diet on renal, cardiovascular, and bone health of the general population. Increasingly, studies show that phosphorus intakes in excess of the nutrient needs of a healthy population may significantly disrupt the hormonal regulation of phosphate, calcium, and vitamin D, which contributes to disordered mineral metabolism, vascular calcification, impaired kidney function, and bone loss. Moreover, large epidemiologic studies suggest that mild elevations of serum phosphate within the normal range are associated with cardiovascular disease (CVD) risk in healthy populations without evidence of kidney disease. However, few studies linked high dietary phosphorus intake to mild changes in serum phosphate because of the nature of the study design and inaccuracies in the nutrient composition databases. Although phosphorus is an essential nutrient, in excess it could be linked to tissue damage by a variety of mechanisms involved in the endocrine regulation of extracellular phosphate, specifically the secretion and action of fibroblast growth factor 23 and parathyroid hormone. Disordered regulation of these hormones by high dietary phosphorus may be key factors contributing to renal failure, CVD, and osteoporosis. Although systematically underestimated in national surveys, phosphorus intake seemingly continues to increase as a result of the growing consumption of highly processed foods, especially restaurant meals, fast foods, and convenience foods. The increased cumulative use of ingredients containing phosphorus in food processing merits further study given what is now being shown about the potential toxicity of phosphorus intake when it exceeds nutrient needs.
Zinc metabolism in male rats was studied by combining nutritional balance methods with an analysis of 65Zn kinetics. The rats, two groups of 84 each, were fed zinc-adequate diets (33 ppm Zn) with either 0 (basal) or 2% phytic acid added as sodium phytate. A fourth-order exponential function described the time-course of 65Zn in plasma, and compartmental models were developed accordingly. Plasma zinc exchanged more rapidly with zinc in liver and kidneys than it did with zinc in testes, skeletal muscle, or bone. Total body zinc content (2.6 mg/100 g live body weight) measured chemically was about 9 times higher than estimates of exchangeable zinc in the body. Whole-body retention of 65Zn was higher and endogenous fecal zinc excretion was lower in rats fed phytate than in those fed the basal diet; these responses to phytate may reflect a homeostatic adjustment to decreased absorption of zinc. Respective values for apparent absorption and true absorption of zinc were 13 and 32% of zinc intake in rats fed phytate, and 19 and 46% of zinc intake in rats fed the basal diet. When whole grains or mature seeds constitute a major portion of the diet, the phytate: zinc molar ratio may approach that (60:1) used in our study. Whether or not phytic acid occurring naturally in foods affects zinc metabolism to the same extent as sodium phytate can not be determined from our study.
Human risk assessment of exposure to 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) through the diet may be improved by conducting biomonitoring studies comparing metabolism in humans and rodents. Eleven volunteers ingested a meal of cooked chicken containing 4 -OH-PhIP and PhIP in amounts of 0.6 and 0.8microg/kg, respectively and urine was collected for the next 16h. The large number of PhIP metabolites was by treatment of the urine samples with hydrazine hydrate and hydrolytic enzymes reduced to three substances, 4'-OH-PhIP, PhIP and 5-OH-PhIP of which the first is a biomarker for detoxification and the last a biomarker for activation. The eleven volunteers eliminated large amounts of 4'-OH-PhIP in the urine. The majority of which could be accounted for by the presence of 4'-OH-PhIP in the fried chicken, showing that PhIP only to a small extent (11%) was metabolised to 4'-OH-PhIP. A larger fraction of the PhIP exposure, 38%, was recovered as PhIP and the largest fraction (51%) was recovered as 5-OH-PhIP suggesting that PhIP in humans to a large extent is metabolised to reactive substances. In rats, less than 1% of the dose of PhIP was eliminated as 5-OH-PhIP, suggesting that human cancer risk from exposure to PhIP is considerable higher than risk estimations based on extrapolation from rodent bioassays.
Purple discoloration of the large bowel at autopsy was related to beetroot ingestion and post-mortem changes.
In the early 1970s, aluminium toxicity was first implicated in the pathogenesis of clinical disorders in patients with chronic renal failure involving bone (renal osteomalacia) or brain tissue (dialysis encephalopathy). Before that time the toxic effects of aluminium ingestion were not considered to be a major concern because absorption seemed unlikely to occur. Meanwhile, aluminium toxicity has been investigated in countless epidemiological and clinical studies as well as in animal experiments and many papers have been published on the subject. It is now commonly acknowledged that aluminium toxicity can be induced by infusion of aluminium-contaminated dialysis fluids, by parenteral nutrition solutions, and by oral exposure as a result of aluminium-containing pharmaceutical products such as aluminium-based phosphate binders or antacid intake. Over-the-counter antacids are the most important source for human aluminium exposure from a quantitative point of view. However, aluminium can act as a powerful neurological toxicant and provoke embryonic and fetal toxic effects in animals and humans after gestational exposure. Despite these facts, the patient information leaflets from European antacids that are available OTC show substantial differences regarding warnings from aluminium toxicity. It seems advisable that all patients should receive the same information on aluminium toxicity from patient information leaflets, in particular with regard to the increased absorption through concomitant administration with citrate-containing beverages and the use of such antacids during pregnancy.
The determination of Al, B, Cu, Fe, Mn, Ni, P, Zn and Ca, K, Mg by inductively coupled plasma optical emission spectrometry (ICP-OES) and flame atomic absorption spectroscopy (FAAS), respectively, in digests and infusions of Hibiscus sabdariffa (petals), Rosa canina (receptacles), Ginkgo biloba (leaves), Cymbopogon citratus (leaves), Aloe vera (leaves) and Panax ginseng (roots) was carried out in this study. Particular attention has been given to Al and heavy metals for the identification of possible raw material contaminants, their transformation into the infusion and for predicting their eventual role in the human diet during daily consumption. Additionally, Ion Chromatography (IC) speciation of Al in the leachates was carried out. In dry herbs, hibiscus and ginkgo appeared to contain the greatest contents of Al, Fe, K, Mn, Ni, Zn and B, Mg, P, respectively. A. vera contained the highest amount of Ca and highest values of Cu and P were observed in ginseng. In infusions, the topmost concentrations of Al, B, Cu, Fe, P, K, Mn, Ni, Zn were detected in those prepared from hibiscus petals, Ca from aloe leaves and Mg from leaves of ginkgo. According to a possible daily consumption exceeding 1 L, hibiscus decoction was identified as potentially dietetically significant in the content of certain elements. It seems to be possibly one of the top contributors of B from food (up to 5.5±0.2 mg/L). The Mg contained in the infusion (up to 106±5 mg/L) may be a contributor in the attenuation of blood pressure. A high amount of accessible Mn (up to 17.4±1.1 mg/L) can probably have an adverse effect in humans. The total Al allowance (up to 1.2±0.1 mg/L) suggests that no more than 1 L of the hibiscus infusion should be consumed per day by sensitive individuals including pregnant women and should be completely excluded from the diet of children under 6 months of age and children with chronic renal failure. Copyright © 2013 Elsevier Ltd. All rights reserved.
Summary Background and objectives Patients with advanced chronic kidney disease (CKD) are in positive phosphorus balance, but phosphorus levels are maintained in the normal range through phosphaturia induced by increases in fibroblast growth factor-23 (FGF23) and parathyroid hormone (PTH). This provides the rationale for recommendations to restrict dietary phosphate intake to 800 mg/d. However, the protein source of the phosphate may also be important. Design, setting, participants, & measurements We conducted a crossover trial in nine patients with a mean estimated GFR of 32 ml/min to directly compare vegetarian and meat diets with equivalent nutrients prepared by clinical research staff. During the last 24 hours of each 7-day diet period, subjects were hospitalized in a research center and urine and blood were frequently monitored. Results The results indicated that 1 week of a vegetarian diet led to lower serum phosphorus levels and decreased FGF23 levels. The inpatient stay demonstrated similar diurnal variation for blood phosphorus, calcium, PTH, and urine fractional excretion of phosphorus but significant differences between the vegetarian and meat diets. Finally, the 24-hour fractional excretion of phosphorus was highly correlated to a 2-hour fasting urine collection for the vegetarian diet but not the meat diet. Conclusions In summary, this study demonstrates that the source of protein has a significant effect on phosphorus homeostasis in patients with CKD. Therefore, dietary counseling of patients with CKD must include information on not only the amount of phosphate but also the source of protein from which the phosphate derives.
Excessive dietary phosphorus may increase cardiovascular risk in healthy individuals as well as in patients with chronic kidney disease, but the mechanisms underlying this risk are not completely understood. To determine whether postprandial hyperphosphatemia may promote endothelial dysfunction, we investigated the acute effect of phosphorus loading on endothelial function in vitro and in vivo. Exposing bovine aortic endothelial cells to a phosphorus load increased production of reactive oxygen species, which depended on phosphorus influx via sodium-dependent phosphate transporters, and decreased nitric oxide production via inhibitory phosphorylation of endothelial nitric oxide synthase. Phosphorus loading inhibited endothelium-dependent vasodilation of rat aortic rings. In 11 healthy men, we alternately served meals containing 400 mg or 1200 mg of phosphorus in a double-blind crossover study and measured flow-mediated dilation of the brachial artery before and 2 h after the meals. The high dietary phosphorus load increased serum phosphorus at 2 h and significantly decreased flow-mediated dilation. Flow-mediated dilation correlated inversely with serum phosphorus. Taken together, these findings suggest that endothelial dysfunction mediated by acute postprandial hyperphosphatemia may contribute to the relationship between serum phosphorus level and the risk for cardiovascular morbidity and mortality.
The fruits (dates) of the date palm (Phoenix dactylifera L.) contain a high percentage of carbohydrate (total sugars, 44-88%), fat (0.2-0.5%), 15 salts and minerals, protein (2.3-5.6%), vitamins and a high percentage of dietary fibre (6.4-11.5%). The flesh of dates contains 0.2-0.5% oil, whereas the seed contains 7.7-9.7% oil. The weight of the seed is 5.6-14.2% of the date. The fatty acids occur in both flesh and seed as a range of saturated and unsaturated acids, the seeds containing 14 types of fatty acids, but only eight of these fatty acids occur in very low concentration in the flesh. Unsaturated fatty acids include palmitoleic, oleic, linoleic and linolenic acids. The oleic acid content of the seeds varies from 41.1 to 58.8%, which suggests that the seeds of date could be used as a source of oleic acid. There are at least 15 minerals in dates. The percentage of each mineral in dried dates varies from 0.1 to 916 mg/100 g date depending on the type of mineral. In many varieties, potassium can be found at a concentration as high as 0.9% in the flesh while it is as high as 0.5% in some seeds. Other minerals and salts that are found in various proportions include boron, calcium, cobalt, copper, fluorine, iron, magnesium, manganese, potassium, phosphorous, sodium and zinc. Additionally, the seeds contain aluminum, cadmium, chloride, lead and sulphur in various proportions. Dates contain elemental fluorine that is useful in protecting teeth against decay. Selenium, another element believed to help prevent cancer and important in immune function, is also found in dates. The protein in dates contains 23 types of amino acids, some of which are not present in the most popular fruits such as oranges, apples and bananas. Dates contain at least six vitamins including a small amount of vitamin C, and vitamins B(1) thiamine, B(2) riboflavin, nicotinic acid (niacin) and vitamin A. The dietary fibre of 14 varieties of dates has been shown to be as high as 6.4-11.5% depending on variety and degree of ripeness. Dates contain 0.5-3.9% pectin, which may have important health benefits. The world production of dates has increased 2.9 times over 40 years, whereas the world population has doubled. The total world export of dates increased by 1.71% over 40 years. In many ways, dates may be considered as an almost ideal food, providing a wide range of essential nutrients and potential health benefits.
Campylobacter spp. are nutritionally fastidious organisms that are sensitive to normal atmospheric oxygen levels and lack homologues of common cold shock genes. At first glance, these bacteria seem ill equipped to persist within food products under processing and storage conditions; however, they survive in numbers sufficient to cause the largest number of foodborne bacterial disease annually. A mechanism proposed to play a role in Campylobacter survival is the addition of polyphosphate-containing marinades during poultry processing. Campylobacter jejuni and Campylobacter coli strains incubated in chicken exudates collected from poultry treated with a marinade demonstrated considerable survival advantages (1 to 4 log CFU/ml) over the same strains incubated in chicken exudate from untreated birds. Polyphosphates, which constitute a large portion of the commercial poultry marinades, were shown to account for a majority of the observed influence of the marinades on Campylobacter survival. When six different food grade polyphosphates (disodium pyrophosphate, tetrasodium pyrophosphate, pentasodium triphosphate, sodium polyphosphate, monosodium phosphate, and trisodium phosphate) were utilized to compare the survival of Campylobacter strains in chicken exudate, significant differences were observed with regard to Campylobacter survival between the different polyphosphates. It was then determined that the addition of polyphosphates to chicken exudate increased the pH of the exudate, with the more sodiated polyphosphates increasing the pH to a greater degree than the less sodiated polyphosphates. It was confirmed that the change in pH mediated by polyphosphates is responsible for the observed increases in Campylobacter survival.
Hyperphosphatemia and hyperparathyroidism, frequently observed in patients with endstage renal disease, are associated with renal osteodystrophy, organ calcification, cardiovascular disease and sudden death. Restriction of dietary protein and phosphorus is beneficial in slowing the progression of renal failure. Dietary phosphorus restriction must be prescribed at all stages of renal failure in adults. It may be achieved by decreasing protein intake and avoiding foods rich in phosphorus. An average of 60-80% of the phosphorus intake is absorbed in the gut in dialysis patients. If phosphate binders are employed, the phosphorus absorbed from the diet may be reduced to 40%. Conventional hemodialysis with a high-flux, high-efficiency dialyzer removes approximately 30 mmol (900 mg) phosphorus during each dialysis performed three times weekly. Therefore, 750 mg of phosphorus intake should be the critical value above which a positive balance of phosphorus may occur. This value corresponds to a protein diet of 45-50 g/day or 0.8 g/kg body weight/day for a 60 kg patient. Target levels should become 9.2-9.6 mg/dl for calcium, 2.5-5.5 mg/dl for phosphorus, <55 mg2/dl2 for the calcium-phosphorus product, and 100-200 pg/ml for intact parathyroid hormone.
Twenty three adults ingested 203Pb as lead acetate on the 12th hour of a 19 h fast. Retention measured 7 days later in a whole-body counter was 61% and whole-body turnover rates suggested that initial uptake had been considerably greater. Balanced meals eaten with 203Pb reduced lead uptake to 4% and the influence of the food lasted for up to 3 h. The effects of phytate, ethylene-diaminetetra acetate (EDTA), caffeine, alcohol, glucose, a liquid meal and a light snack were tested separately with intermediate results. The effect of a meal was probably largely due to its content of calcium and phosphate salts but lead uptake was probably further reduced by phytate which is plentiful in whole cereals and it was probably increased by a factor in milk. Uptake with skimmed milk was the same as with whole milk and we suggested that the factor was not fat. Comestibles with low mineral and phytate contents reduced lead uptake by intermediate amounts, possibly by stimulation of digestive secretions. The avid uptake of lead during a fast, the large reduction of lead uptake with meals and the likelihood of variations in gastric-emptying rates and dietary habits may be major causes of variation in body burdens of lead in the population.
Ten healthy men ingested, twice daily between meals, during each of the seven-day experimental periods: (a) citric acid (as lemon juice), (b) Al(OH)3, or (c) Al(OH)3 + citric acid. Whole blood sampled after each dietary period was analyzed electrothermally after digestion with nitric acid. Moderate, but significant, increases in mean Al concentrations as compared with pretreatment values [5 (SD 3) micrograms of Al per liter] were seen after ingestion of either citric acid or Al(OH)3: 9 (SD 4) and 12 (SD 3) micrograms/L, respectively. Ingestion of both Al(OH)3 and citric acid resulted in a more pronounced, highly significant (p less than 0.001) increase in Al concentrations, to 23 (SD 2) micrograms Al/L, probably owing to formation and absorption of Al-citrate complexes.
The effects of maize-bran phytate and of a polyphenol (tannic acid) on iron absorption from a white-bread meal were tested in 199 subjects. The phytate content was varied by adding different concentrations of phytate-free and ordinary maize bran. Iron absorption decreased progressively when maize bran containing increasing amounts of phytate phosphorous (phytate P) (from 10 to 58 mg) was given. The inhibitory effect was overcome by 30 mg ascorbic acid. The inhibitory effects of tannic acid (from 12 to 55 mg) were also dose dependent. Studies suggested that greater than or equal to 50 mg ascorbic acid would be required to overcome the inhibitory effects on iron absorption of any meal containing greater than 100 mg tannic acid. Our findings indicate that it may be possible to predict the bioavailability of iron in a diet if due account is taken of the relative content in the diet of the major promoters and inhibitors of iron absorption.
Nine catfish fillets, three catfish nuggets, two feed samples, and one pond sediment were analyzed for PCDD, PCDF, and PCB. Farm-raised catfish from Mississippi, Alabama, and Arkansas contained significant levels of 2,3,7,8-substituted PCDD and PCDF. In addition, a large number of non-2,3,7,8-substituted congeners were present in all samples. The catfish fillets and catfish nuggets also contained high concentrations of dioxin-like PCB, as well as a number of non-dioxin-like PCB. The TEQ based on PCDD and PCDF ranged from 9.5 to 43.0 pg/g lipid and the TEQ based on PCB ranged from 0.45 to 4.9 pg/g lipid for all catfish samples. The dioxin-like PCB contributed 4-16% to the total TEQ (PCDD/PCDF/PCB) for the catfish samples. The major source for the PCDD, PCDF, and PCB appears to be from feed and not from pond sediment. Immunoreactive CYP1A protein was elevated 2.5 fold in the pond-raised catfish compared to the aquarium-raised one. The results of this study suggest that the PCDD/PCDF are more important than the PCB in the CYP1A induction.
Pesticides are used throughout the world as mixtures called formulations. They contain adjuvants, which are often kept confidential and are called inerts by the manufacturing companies, plus a declared active principle, which is usually tested alone. We tested the toxicity of 9 pesticides, comparing active principles and their formulations, on three human cell lines (HepG2, HEK293, and JEG3). Glyphosate, isoproturon, fluroxypyr, pirimicarb, imidacloprid, acetamiprid, tebuconazole, epoxiconazole, and prochloraz constitute, respectively, the active principles of 3 major herbicides, 3 insecticides, and 3 fungicides. We measured mitochondrial activities, membrane degradations, and caspases 3/7 activities. Fungicides were the most toxic from concentrations 300–600 times lower than agricultural dilutions, followed by herbicides and then insecticides, with very similar profiles in all cell types. Despite its relatively benign reputation, Roundup was among the most toxic herbicides and insecticides tested. Most importantly, 8 formulations out of 9 were up to one thousand times more toxic than their active principles. Our results challenge the relevance of the acceptable daily intake for pesticides because this norm is calculated from the toxicity of the active principle alone. Chronic tests on pesticides may not reflect relevant environmental exposures if only one ingredient of these mixtures is tested alone.
Four persons developed marked parkinsonism after using an illicit drug intravenously. Analysis of the substance injected by two of these patients revealed primarily 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP) with trace amounts of 1-methyl-4-phenyl-4-propionoxy-piperidine (MPPP). On the basis of the striking parkinsonian features observed in our patients, and additional pathological data from one previously reported case, it is proposed that this chemical selectively damages cells in the substantia nigra.
Reducing the concentration of polyamines (spermine, spermidine, and putrescine) in the body pool may slow the cancer process. Because dietary spermine, spermidine, and putrescine contribute to the body pool of polyamines, quantifying them in the diet is important. Limited information about polyamine content of food is available, especially for diets in the United States. This brief report describes the development of a polyamine database linked to the Fred Hutchinson Cancer Center food frequency questionnaire (FFQ). Values for spermine, spermidine, and putrescine were calculated and reported per serving size (nmol/serving). Of the foods from the database that were evaluated, fresh and frozen corn contain the highest levels of putrescine (560,000 nmol/serving and 902,880 nmol/serving) and spermidine (137,682 nmol/serving and 221,111 nmol/serving), and green pea soup contains the highest concentration of spermine (36,988 nmol/serving). The polyamine database and FFQ were tested with a convenience sample (n=165). Average daily polyamine intakes from the sample were: 159,133 nmol/day putrescine, 54,697 nmol/day spermidine, and 35,698 nmol/day spermine. Orange and grapefruit juices contributed the greatest amount of putrescine (44,441 nmol/day) to the diet. Green peas contributed the greatest amount of spermidine (3,283 nmol/day) and ground meat contributed the greatest amount of spermine (2,186 nmol/day). Development of this database linked to an FFQ provides a means of estimating polyamine intake and contributes to investigations relating polyamines to cancer.
The incidence of colonic cancer differs widely between various human populations. It has been suggested that dietary fiber content is of utmost importance and is inversely related to the occurrence of colonic cancer. However, high-fiber diets are not always correlated with low frequency of colonic cancer, suggesting the involvement of additional dietary constituents. Inositol hexaphosphate (phytic acid) is an abundant plant seed component present in many, but not all, fiber-rich diets. The authors have found that phytic acid is a potent inhibitor of iron-mediated generation of the hazardous oxidant, hydroxyl radical. Herein, the authors propose that inhibition of intracolonic hydroxyl radical generation, via the chelation of reactive iron by phytic acid, may help explain the suppression of colonic carcinogenesis and other inflammatory bowel diseases by diets rich in phytic acid.
The regular occurrence of a peak due to an unidentified substance (X) in the gas chromatographic traces obtained from phenolic extracts of urine from human pregnant and non-pregnant females has been reported. The biphasic excretion of X with maxima in the luteal phase of the ovulatory cycle and relatively high levels in the first trimester of pregnancy were noteworthy and suggested that the substance may have a biological significance. Close similarities between the excretory pattern, the chemical and chromatographic properties of X and of those of the known phenolic steroids suggested initially that this compound was steroidal in nature. The same, or a similar, substance seems to be excreted in the vervet monkey (Cercopithecus aethiops pygerythrus). We now report the excretory pattern of X in more detail, the isolation of the pure compound from pooled pregnancy urine and the chemical structure. The structure determined by mass spectrometry, IR spectroscopy and NMR spectrometry is: trans-(+/-)-3,4-bis[(3-hydroxyphenyl)methyl]dihydro-2-(3H)-furanone (HPMF) and was confirmed by synthesis.
Mean faecal pH values did not differ significantly in groups of rural South African Black schoolchildren of 10--12 years who ate their traditional high-fibre low-fat diet, and urban dwellers who consumed a partially westernized diet. However, both means were significantly lower than those of groups of White schoolchildren. In feeding studies of 5 days' duration, mean faecal pH value of Black children became significantly less acid when white bread replaced maize meal, and became significantly more acid when a supplement of 6 oranges was consumed daily. Supplements which consisted of skim milk, butter, and sugar had no significant effect on mean faecal pH value. In White children in an institution, the mean pH value of faeces became significantly more acid when a supplement of 6 oranges, although not of bran 'crunchies', was consumed daily.
One combined catfish feed sample from Arkansas, USA, and its eight ingredients were analyzed for PCDDs and PCDFs. One of the ingredients, soybean meal, was highly contaminated by PCDDs, especially the toxic 2,3,7,8-substituted congeners, e.g., 7.3 pg/g dry weight or 370 pg/g lipid for the 2,3,7,8-tetra CDD. The I-TEQ value for the soybean meal was 11.4 pg/g dry weight or 576 pg/g fat. The corresponding values for the combined catfish feed concentrations were approximately 3 times lower. The congener pattern, the congener profile and the ratio sigma PCDDs/sigma PCDFs for the soybean meal were quite unique. We are not aware of any environmental sample or technical product with similar characteristics. As a result, natural formation of the PCDDs found in the soybean meal cannot be ruled out.
Glyphosate surfactant herbicide (GlySH) toxicity is an uncommon poisoning. We report two fatalities involving suicidal ingestion of this herbicide. Both deaths occurred despite early recognition of the serious nature of the poisoning and aggressive treatment. The deaths in this series are analysed in the context of a review of existing literature. Although traditionally regarded as minimally toxic, many deaths have been reported following suicidal ingestion. Severe GlySH toxicity may be refractory even to the most intensive supportive care. The triad of pulmonary oedema, metabolic acidosis and hyperkalaemia portends poor outcome. While containing a carbon phosphorus moiety, GlySH does not exhibit organophosphate toxicity. A clinical guide to assessing severity of GlySH toxicity is proposed and treatment modalities discussed.