Carryover of aflatoxins from feed to lambari fish (Astyanax altiparanae) tissues.

The aim of this study was to verify the carryover of aflatoxin B1 from feed to lambari fish. Aflatoxins (AF) were incorporated into feed, checking the levels by HPLC. Treatments were: Control, feed without toxin; A, feed + 10 µg AFB1 kg-1; B, feed + 20 µg AFB1 kg-1; and C, feed + 50 µg AFB1 kg-1. Juveniles of lambari fish were placed in 12 aquariums at a density of 50 fish/m2. Fish were fed twice a day with extruded feed, at 5% of animal biomass. The unit sample was constituted by a pool of 10 fish. AFs B1, B2, G1, G2 and M1 were quantified by HPLC in fish muscle and liver after 30, 60, 90 and 120 days of experiment. There was accumulation of AFs is fish liver and muscle, mainly after 90 days. Fish from treatment C had higher levels of AFB1 in muscle when compared with the others, and AFB1 in muscle at 120 days was similar to the levels in feed. Therefore, when lambari fish is exposed on a daily and long-term basis to AFs in feed, the regulation limits for AFs in animal feed do not guarantee safety for consumers.

In-vitro and in-vivo evaluation of austocystin D liposomes.

OBJECTIVES: The purpose this study is to enhance the anti-tumour activity of austocystin D (AD) by AD-loaded liposomes (AD-Ls). METHODS: AD-Ls were prepared by the film dispersion-ultrasonication method and characterized in terms of particle size and zeta potential, encapsulation efficiency and in-vitro drug release. In vivo, the pharmacokinetics, biodistribution and anti-tumour effect were also compared with those of the solution. KEY FINDINGS: The obtained liposomes were a mildly translucent suspension, with a particle size of 71.26 ± 6.43 nm, a polydispersity index of 0.259 ± 0.017 and a zeta potential of -9.9 ± 1.8 mV. Transmission electron microscope examination showed that the liposomes had a spherical shape and a multilayer structure. The encapsulation efficiency ofAD-Ls was 83.74 ± 1.26%. AD was continuously released from liposomes up to 72 h in in-vitro experiments. The growth of HT-29 tumours in animal models was controlled more effectively by AD-LS than by AD solution. Pharmacokinetic study showed that AD-Ls had higher t½ß and mean retention time. Biodistribution results in tumour-bearing mice showed that the AD-LS could target to liver and tumour. CONCLUSIONS: This study indicates that AD-Ls are a potential carrier of AD for the treatment of tumours in the liver, increasing the cure efficiency and decreasing the side effects on other tissues.

Identification of maize genes associated with host plant resistance or susceptibility to Aspergillus flavus infection and aflatoxin accumulation.

BACKGROUND: Aspergillus flavus infection and aflatoxin contamination of maize pose negative impacts in agriculture and health. Commercial maize hybrids are generally susceptible to this fungus. Significant levels of host plant resistance have been observed in certain maize inbred lines. This study was conducted to identify maize genes associated with host plant resistance or susceptibility to A. flavus infection and aflatoxin accumulation. RESULTS: Genome wide gene expression levels with or without A. flavus inoculation were compared in two resistant maize inbred lines (Mp313E and Mp04:86) in contrast to two susceptible maize inbred lines (Va35 and B73) by microarray analysis. Principal component analysis (PCA) was used to find genes contributing to the larger variances associated with the resistant or susceptible maize inbred lines. The significance levels of gene expression were determined by using SAS and LIMMA programs. Fifty candidate genes were selected and further investigated by quantitative RT-PCR (qRT-PCR) in a time-course study on Mp313E and Va35. Sixteen of the candidate genes were found to be highly expressed in Mp313E and fifteen in Va35. Out of the 31 highly expressed genes, eight were mapped to seven previously identified quantitative trait locus (QTL) regions. A gene encoding glycine-rich RNA binding protein 2 was found to be associated with the host hypersensitivity and susceptibility in Va35. A nuclear pore complex protein YUP85-like gene was found to be involved in the host resistance in Mp313E. CONCLUSION: Maize genes associated with host plant resistance or susceptibility were identified by a combination of microarray analysis, qRT-PCR analysis, and QTL mapping methods. Our findings suggest that multiple mechanisms are involved in maize host plant defense systems in response to Aspergillus flavus infection and aflatoxin accumulation. These findings will be important in identification of DNA markers for breeding maize lines resistant to aflatoxin accumulation.

Aflatoxins upregulate CYP3A4 mRNA expression in a process that involves the PXR transcription factor.

Pregnane X receptor (PXR) is a member of the nuclear hormone receptor (NHR) superfamily, which regulates xenobiotic and endobiotic metabolism in the liver. This transcription factor is activated by structurally diverse ligands, including drugs and environmental pollutants. PXR regulates the expression of numerous genes that function in biotransformation and the disposition of xenobiotics upon binding to an AG(G/T)TCA DNA motif in target promoter regions. We performed a screen of mycotoxins that pose a known environmental threat to human and animal health for the ability to activate PXR function in a human hepatocyte cell line, HepG2. We found that aflatoxins B1, M1, and G1 activated PXR. This activation was associated with upregulation of CYP3A4 expression and increased occupancy of PXR protein on the CYP3A4 promoter. Using a microarray approach, we also found that aflatoxin B1 upregulated the expression of multiple genes involved in xenobiotic metabolism, including genes known to be regulated in a PXR-dependent fashion. We also observed an effect of aflatoxin B1 on the expression in other functional groups of genes, including the downregulation of genes involved in cholesterologenesis. The results of this study indicate that aflatoxin B1 is able to activate PXR, a known regulator of liver xenobiotic metabolism, in human hepatocytes, and it can upregulate the expression of PXR-dependent genes responsible for aflatoxin B1 biotransformation, including CYP3A4.

A simple steady-state model for carry-over of aflatoxins from feed to cow's milk.

A simple steady-state model is derived from two kinetic one-compartment models for the disposition of aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1) in the lactating cow. The model relates daily intake of AFB1 in feed of dairy cattle and the cow's lactation status to resulting concentrations of AFM1 in milk. Moreover, assuming a linear relationship between the cow's lactation status and feed intake, the model relates daily milk production and AFB1 concentration in total feed to AFM1 levels in milk. The model explains similar experimental outcomes from different investigations into carry-over of aflatoxins from feed to milk. Although it is difficult to set a permanent limit for AFB1 in feed, the European Union (EU) limit of 5 microg AFB1 kg(-1) concentrate has proved, thus far, to be an appropriate level in preventing the EU limit of 0.05 microg AFM1 kg(-1) milk being exceeded.

Identification and reduction of urinary aflatoxin metabolites in dogs.

Hydrated sodium calcium aluminosilicate (HSCAS) is a phyllosilicate clay commonly used as an anticaking agent in animal feeds. HSCAS tightly and selectively adsorbs aflatoxin. In 1998, 55 dogs died in Texas after eating dog food containing aflatoxin (150-300 ppb). The corn in the diets was contaminated with aflatoxin. Six dogs were given a low-level, sub-clinical dose of aflatoxin B(1). On average, 71.5% of aflatoxin M(1) cleared within 6 h after dosing, increasing to 90.4% after 12 h. Aflatoxin M(1) was no longer detectable in urine after 48 h. Aflatoxin P(1) was not found in urine compared to large amounts of M(1) and trace amounts of Q(1). In a crossover study, six dogs randomly fed a commercial dog food (no-clay control) or coated with HSCAS (0.5% by weight) were subsequently administered a sub-clinical dose of aflatoxin B(1). Diets were switched and the process repeated. The HSCAS-coated diet significantly reduced urinary aflatoxin M(1) by 48.4%+/-16.6 SD versus the control diet. In conclusion, HSCAS protects dogs fed diets with even minimal aflatoxin contamination. Despite regular and careful ingredient screening for aflatoxin, low concentrations may reach the final product undetected. Therefore, HSCAS may provide the pet food industry further assurance of canine diet safety.

Dietary aflatoxin exposure and chemoprevention of cancer: a clinical review.

Exposure to dietary aflatoxins is considered to be an important risk factor for the development of hepatocellular carcinoma in certain regions of the world. Significant advances have recently been made in understanding the clinical toxicology of aflatoxins. These include the development and validation of biomarkers of exposure and genotoxic effect. These biomarkers are currently being utilized to explore the potential that pharmaceutical interventions may have in modifying the toxicokinetics of dietary aflatoxin exposure. Preliminary results of clinical trials with the drug oltipraz suggest that it may modify the genotoxic effects of aflatoxin B1 by inhibiting bioactivation pathways and stimulating detoxification pathways. More recent results of a clinical trial with chlorophyllin suggest that this drug may have a role in preventing dietary exposure to aflatoxin B1 by reducing its oral bioavailability. The preliminary results of these chemoprevention studies may ultimately have implications for cancer prevention in high-risk populations in the future.

Antimutagenic effects of doenjang (Korean fermented soypaste) and its active compounds.

Doenjang (Korean fermented soypaste) is one of the important fermented foods of Korea. Doenjang has been traditionally manufactured from meju, which is fermented rectangular shape molded from crushed cooked soybeans. The main microorganisms involved for meju fermentation are Bacillus subtilis and molds such as Rizopus sp., Mucor sp., and Aspergillus sp. We have already reported that doenjang is safe from mycotoxin, especially, aflatoxin contamination due to the manufacturing process of the doenjang. We have demonstrated that the doenjang extracts showed strong antimutagenic activities against various carcinogens/mutagens including aflatoxin B(1). The traditionally fermented soypaste, doenjang showed higher antimutagenic activity than the raw soybeans, cooked soybeans, meju and other fermented soybeans in the Ames test. The active compounds that were identified are genistein, linoleic acid, beta-sitosterol glucoside, soyasaponin, etc. The active compounds exhibited strong antimutagenic activities in the Ames test, SOS chromotest and Drosophila wing spot test. More genistein was formed during the doenjang fermentation from genistin in the soybeans. Genistein and linoleic acid were the most effective active compounds found in doenjang.

Differences detected in vivo between samples of aflatoxin-contaminated peanut meal, following decontamination by two ammonia-based processes.

A sample of peanut meal, highly contaminated with aflatoxins, has been subjected to decontamination by two commercial ammonia-based processes. The original contaminated and the two decontaminated meals were fed to rats for 90 days. No lesions associated with aflatoxin-induced hepatocarcinogenesis were detected histologically following feeding with the two detoxified meals. There were, however, clear differences between the two meals in respect of growth rates of the rats. In addition, feeding one of the detoxified meals resulted in hepatic abnormalities detected using novel immunohistochemical reagents. Differences between the two detoxified meals were also indicated by the results of studies using meals 'spiked' with [14C]-aflatoxin B1 prior to being subjected to the detoxification processes. The meals differed in the bioavailability of the label. It was concluded that peanut meal where an initial, unacceptable level of contamination with aflatoxins had been reduced by two ammonia-based processes to comparable, acceptable levels, may still have different effects in vivo when incorporated into animal diets.

Interindividual differences in response to chemoprotection against aflatoxin-induced hepatocarcinogenesis: implications for human biotransformation enzyme polymorphisms.

It is now evident that most, if not all, of the remarkable species differences in susceptibility to AFB hepatocarcinogenesis is due in large part, if not exclusively, to differences in biotransformation. Certainly the relative rate of oxidative formation of the proximate carcinogen, AFB-8,9-exo-epoxide, is an important determinant of species and interindividual differences in susceptibility to AFB. However, mice produce relatively large amounts of exo-AFBO, yet are highly resistant to AFB-hepatocarcinogenesis because they express a particular form of GST with remarkably high catalytic activity toward the exo-epoxide of AFB. Rats, which are highly susceptible to AFB hepatocarcinogenesis,can be made resistant through dietary induction of an orthologous form of GST that is normally expressed in only very small amounts. Based on these findings in laboratory animal models, there is great interest in identifying chemicals and/or specific dietary constituents that could offer protection against AFB-hepatocarcinogenesis to humans. Current experimental strategies have focused on the antiparasitic drug, oltipraz, which induces protection in rats and has also shown some promise in humans. The mechanism of protection in rats appears to be via induction of an alpha class GST with high catalytic activity toward AFBO (rGSTA5-5). vet human alpha class GST proteins that are constitutively expressed in the liver (hGSTA1 and hGSTA2) have little, if any activity toward AFBO. Rather, it appears that mu class GSTs may be responsible for the very low, but potentially significant, detoxification activity toward AFBO. Oltipraz and certain dietary constituents may induce mu class GSTs in human liver, and this could afford some protection against the genotoxic effects of AFBO. However, it also appears that oltipraz, and perhaps certain dietary constituents, act as competitive inhibitors of human CYP1A2. As CYP1A2 appears to mediate most of the activation of AFB to exo-AFBO in human liver at low dietary concentrations of AFB encountered in the human diet, much of the putative protective effects of oltipraz could be mediated via inhibition of CYP1A2 rather than induction of GSTs. There is now evidence that human microsomal epoxide hydrolase (mEH) could play a role in protecting human DNA from the genotoxic effects of AFB, although the importance of this detoxification pathway, relative to mu class GSTs, remains to be elucidated. Oltipraz is an effective inducer of mEH in rats (Lamb Franklin, 2000), and thus induction of this pathway in humans could also potentially contribute to the protective effects of this drug toward AFB genotoxicity. Because the dihydrodiol of AFB may contribute indirectly to the carcinogenic effects of AFB via protein adduction and subsequent hepatotoxicity, the recently characterized human aflatoxin aldehyde reductase (AFAR) may also offer some protection against AFB-induced carcinogenicity in humans. Current and future dietary and/or chemointervention strategies aimed at reducing the carcinogenic effects of AFB in humans should consider all of the possible mechanistic approaches for modifying AFB-induced genotoxicity.

Mechanisms of chlorophyllin anticarcinogenesis: dose-responsive inhibition of aflatoxin uptake and biodistribution following oral co-administration in rainbow trout.

Chlorophyllin (CHL) is a potent blocking agent against aflatoxin B(1) DNA adduction and tumorigenesis in the trout model, but mechanisms responsible for this chemoprotection in vivo are not well established. This study employed aflatoxin B(2) (AFB(2)), a structural analogue of AFB(1) that cannot be metabolized directly to the 8,9-exo-epoxide electrophile, to investigate CHL effects on carcinogen uptake and distribution kinetics following oral exposure in trout. CHL was shown to form an AFB(2) complex in vitro with a dissociation constant (K(d) = 1.92 +/- 0.13 microM) comparable to that with AFB(1). Following gavage, [(3)H]AFB(2) equivalents distributed rapidly from the stomach to other organs including blood, liver, and eventually to bile as a major repository. Bile was found to contain almost entirely parent AFB(2) 1 h after gavage, with a single metabolite dominating 3-24 h and an additional metabolite prominent by 48 h after gavage. Addition of sufficient CHL (>/=13.9 mM) to assure >99% complexation of AFB(2) (0.906 microM) in the gavage mix resulted in 80-90% reduction in AFB(2) equivalents in liver and bile 3 h after gavage. In three separate kinetic studies of up to 120 h postgavage, addition of >/=13.9 mM CHL to the gavage mix reproducibly and markedly delayed the rate of AFB(2) loss from stomach, retarded its appearance in blood, liver, and bile, and reduced peak AFB(2) concentrations in those tissues by up to 60%. Introduction of a food bolus immediately after gavage prolonged AFB(2) residence in stomach and intestine but did not abrogate the inhibitory effects of CHL on AFB(2) uptake and distribution. These results demonstrate that oral co-treatment with CHL under conditions where complex formation is initially assured, substantially reduces AFB(2) systemic uptake and target organ bioavailability in the trout.

Chlorophyllin chemoprevention in trout initiated by aflatoxin B(1) bath treatment: An evaluation of reduced bioavailability vs. target organ protective mechanisms.

Chlorophyllin (CHL) is known to inhibit DNA adduction and hepatocarcinogenesis in trout when administered at doses up to 4000 ppm in the diet with aflatoxin B(1) (AFB(1)). The principal protective mechanism is believed to involve CHL:AFB(1) complex formation, which may reduce systemic carcinogen absorption. However, mechanisms operative within the target organ in situ have not been ruled out. The present study used alternative CHL and AFB(1) exposures as well as hepatic metabolism studies to distinguish these mechanisms. Duplicate lots of 150 rainbow trout each were initiated by brief water bath exposure to 0.1 ppm AFB(1), with or without 500 ppm CHL in the water. The addition of 500 ppm CHL to the water bath, under conditions where AFB(1) is calculated to be >99% sequestered as the CHL:AFB(1) complex, reduced hepatic AFB(1)-DNA adduction by 95% and reduced hepatocarcinogenesis from 20.5% to 2%, compared with exposure to AFB(1) alone. Inclusion of 500 ppm CHL in the water bath also significantly reduced total body burden and hepatic levels of AFB(1) as well as AFB(2), a structural analogue of AFB(1) unable to directly form the 8,9-epoxide proximate electrophile but equally capable of complexing with CHL. By contrast, internal target organ CHL loading by pretreatment of trout with 4000 ppm dietary CHL for 7 days prior to (and 2 days following) AFB(1) waterbath exposure had no effect on AFB(1)-DNA adduction or tumorigenicity. Dietary CHL up to 8000 ppm had no effect on hepatic CYP2K1, CYP1A, glutathione transferase, UDP-glucuronosyl transferase, or, with one exception, the relative ratios among hepatic AFB(1) metabolites in vivo. These results support the hypothesis that CHL:AFB(1) complex formation and reduced systemic AFB(1) bioavailability is a principal mechanism for CHL chemoprevention in this model and that in situ target organ inhibitory mechanisms are relatively insignificant.

Modeling and experimental comparison of the differential adsorption of B1 and G1 aflatoxins on mineral aluminosilicate surfaces.

Aflatoxins produced by Aspergillus fungus are secondary metabolites undergoing biotransformation rates in hepatic tissues and lipid peroxidation. Although the use of adsorbent materials became a common practice for feed grain detoxification, fundamental studies are needed to clarify the interaction occurring between mineral surfaces and organic molecules. We evaluated the differential adsorption of B1 and G1 on 10 adsorbent materials and compared it in vitro by means of fluorescence emission from solution. Three aluminosilicates showed no adsorption of B1 at all, whereas only one was inactive for G1 adsorption and seven of them showed 15.2 to 77.9% adsorption for B1 and 8.3 to 78% for G1. All these adsorbents were more selective toward G1 rather than B1 aflatoxins. This behavior can be explained by the presence of an additional cyclic ester in G1, which provides a higher electronic density to G1 molecules, thus forming more stable hydrogen bridges with respect to the cyclopentanone ring present in B1.

Effects of a hydrated sodium calcium aluminosilicate (T-Bind) on mycotoxicosis in young broiler chickens.

Experiments were conducted to determine the ability of a hydrated sodium calcium aluminosilicate (T-Bind) sorbent to reduce the toxicity of aflatoxins (AF) or T-2 toxin in male broiler chickens from day of hatch to 21 d of age. In Experiment 1, the sorbent was added at 0.250 or 0.375% to diets containing AF at 5 or T-2 toxin at 8 mg/kg of diet. When compared with controls, AF reduced BW gain by 27% and T-2 toxin reduced BW gain by 17%. The addition of the sorbent at 0.250 or 0.375%, in the absence of added mycotoxins, did not alter the performance of the chicks. The sorbent reduced the toxic effects of 5 mg AF/kg of diet on BW gain by 43% but did not significantly diminish the toxic effects of 8 mg T-2 toxin/kg of diet. The decreased efficiency of feed utilization and the increased relative organ weights caused by AF were significantly diminished to differing degrees by the sorbent. Oral lesions caused by T-2 toxin were not affected by the sorbent. In Experiment 2, the sorbent was added at 0.80% to a diet containing 8 mg T-2 toxin/kg of diet. The sorbent did not diminish the toxic effects of T-2 toxin when added at 0.80% of the diet. These data demonstrate that this specific sorbent can provide protection against the toxicity of AF, but not T-2 toxin, in young broiler chicks.

Dietary exposure of broiler breeders to aflatoxin results in immune dysfunction in progeny chicks.

Broiler breeder hens were fed diets amended with 0 and 10 mg/kg (Trial 1) or 0, 0.2, 1, or 5 mg/kg (Trial 2) of aflatoxin (AF). Fertile eggs collected during 14 d of AF feeding were examined for AF residues. Various immunological endpoints were examined in chicks hatched from these eggs. Eggs collected at 7 d of AF feeding (Trial 1) had 0.15 to 0.48 ng/g of AFB1 and 0.22 to 0.51 ng/g of aflatoxicol, whereas eggs collected at 14 d of AF feeding had 0.05 to 0.60 ng of AFB1/g and 0.19 to 1.20 ng of aflatoxicol/g. In both trials, AF dietary exposure resulted in embryonic mortality and reduction in hatchability compared to controls. The AF progeny chicks in Trial 2 had total anti-SRBC antibodies similar to the controls during the primary antibody response. However, at 5 and 7 d after secondary SRBC injection, the antibody levels in the 1 and 5 mg/kg AF groups were lower than those of controls. Depression in anti-Brucella abortus antibodies occurred only in chicks from the 5 mg/kg AF group. Furthermore, phagocytosis of SRBC and reactive oxygen intermediate production by macrophages from AF progeny chicks were reduced as compared with the control chicks. The findings of this study imply that the progeny chicks from hens consuming a AF-amended diet may be increasingly susceptible to disease owing to suppression of humoral and cellular immunity.

Aflatoxinas en salud humana

Las micotoxinas son metabolitos secudarios de hongos toxigénicos que pueden contaminar alimentos de consumo humano y animal, constituyéndose en riesgo potencial de enfermedad; hoy se conocen aproximadamente 500, entre las que se encuentran las aflatoxinas. De ésta, se han identificado 18, siendo la más importante la aflatoxina B1, considerada sustancia cancérigena en animales de experimentación. Las aflatoxinas se encuentran en cereales, nueces, frutas y semillas oleaginosas. El consumo agudo puede producir emesis, dolor abdominal, edema pulmonar, infiltración grasa y necrosis hepática. El consumo crónico de bajas cantidades guarda relación con carcinoma he patocelular en humanos. Puede afectar también el sistama inmune, las células T son más susceptibles que las células B y el efecto desaparece el consumo de la aflatoxina. También puede encontrarse anemia, alteración de la coagulación, el tiempo de protrombina y el tiempo de recalcificación del plasma. En colombia no se ha profundizado sobre el tema. Se debe considerar el impacto que pueden tener las aflatoxinas sobre la salud humana y animal.

In situ absorption of aflatoxins in rat small intestine.

To evaluate the rate at which the four main aflatoxins (aflatoxins B1, B2, G1 and G2) are able to cross the luminal membrane of the rat small intestine, a study about intestinal absorption kinetics of these mycotoxins has been made. In situ results obtained showed that the absorption of aflatoxins in rat small intestine is a very fast process that follows first-order kinetics, with an absorption rate constant (ka) of 5.84 +/- 0.05 (aflatoxin B1), 4.06 +/- 0.09 (aflatoxin B2), 2.09 +/- 0.03 (aflatoxin G1) and 1.58 +/- 0.04 (aflatoxin G2) h-1, respectively.

Blood aflatoxin levels in patients with hepatocellular carcinoma in Singapore.

Aflatoxin (AF), a highly potent hepatocarcinogen, is strongly implicated in the pathogenesis of human hepatocellular carcinoma (HCC). In this study, our aim was to determine if this carcinogen is associated with cases of HCC in Singapore. Blood levels of the naturally-occurring AFs--B1, B2, G1 and G2--were assayed in 56 cases of HCC. AF was detected in only 2/56 (3.6%) cases of HCC, one each of AF-B1 and AF-G1. In contrast, in a similar survey done in Singapore on normal subjects, AF was positive in 64/423 (15.1%) cases. The low frequency of AF detection in our patients suggests that HCC in Singapore is not associated with significant chronic exposure to AF.

Aflatoxin and outcome from acute lower respiratory infection in children in The Philippines.

Aflatoxin is immunosuppressive in experimental conditions. This study addressed its potentially contributory role in the poor outcome of acute lower respiratory infections (ALRI) in children in The Philippines. The catchment area included peri-urban slums and middle-class housing. One hundred and fifteen children (mean age 2.1, range 0.08-12 years) were enrolled and their serum and urine obtained at presentation with ALRI. Aflatoxins in serum and aflatoxin metabolites in urine were measured by previously validated ELISA tests. Using the 1986 WHO criteria for the severity of ALRI, 31% had mild, 12% moderate, 49% severe and 8% severe complicated pneumonia. Eighty of 97 (82%) chest radiographs were abnormal. Ninety per cent of the children were below average weight for age, using Filipino standards, with a mean of 79% (range 27-157%). Thirteen (11%) children died. Aflatoxin in their serum, reflecting recent ingestion, was detected in 33%, with a mean positive value of 462 pg/ml. Aflatoxin metabolites (reflecting chronic ingestion) were detected in 64 of 65 urines collected, with a mean value of 0.1-4.77ng/ml. None of the children with detectable serum aflatoxin died. Anorexia and impaired consciousness were strongly associated with a poor outcome (prolonged fever or death). There was a strong association between undetectable serum aflatoxin concentrations and death (p = 0.004), perhaps reflecting anorexia. There was no relationship between the concentration of urinary aflatoxin metabolites and outcome. Serum was also obtained from 29 mothers on admission and none contained detectable aflatoxin. As virtually all the children had evidence of exposure to aflatoxin, a potentially immunosuppressive role in the context of pneumonia cannot be excluded.

PIP: Between December 1986 and January 1987 at the Research Institute for Tropical Medicine, a small hospital serving inhabitants of peri-urban slums and middle-class housing in Alabang, the Philippines, clinical researchers measured aflatoxin in the serum and urine of 115 children aged less than 13 who had a cough for less than three weeks (i.e., acute lower respiratory infection [ALRI]). They wanted to learn whether consumption of aflatoxin found in many foods in the Philippines could increase ALRI-related mortality among Filipino children. Almost all 115 children had probably been exposed to aflatoxin. 59% were admitted to the hospital. 11% of the hospitalized children died. No child died among those not admitted to the hospital. 73% of all children were severely malnourished. 82% had abnormal chest radiographs. 49% had severe ALRI, 31% mild ALRI, 12% moderate ALRI, and 8% severe-complicated ALRI. 67% of the children and none of the mothers had no detectable aflatoxin in their sera. The mean and median aflatoxin levels in the positive sera were 462 and 140 pg/ml, respectively (range, 20-5600 pg/ml). 64 of 65 sera had some aflatoxin metabolites (0.1-4.77 ng/ml). The mean aflatoxin metabolite/creatinine ratio was 1.27 (range, 0.19-4.43). Undetectable serum aflatoxin was associated with death (p = 0.006). Both anorexia and impaired consciousness level were significantly associated with death (p 0.001). The concentration of urinary aflatoxin metabolites had no apparent effect on outcomes. These findings do not support the hypothesis that aflatoxin acts as an immunosuppressant. Since almost all children tested had aflatoxin metabolites (indicating recent ingestion of aflatoxin), however, the researchers could not exclude aflatoxin's role as a potential immunosuppressant.