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PubMed2001

Impact of herbicides on the abundance and structure of indigenous beta-subgroup ammonia-oxidizer communities in soil microcosms.

In this study, mixtures of five herbicide-formulated products (atrazine, dicamba, fluometuron, metolachlor, and sulfentrazone) were applied to soil microcosm columns in increasing concentrations. The toxic impact of herbicides on the indigenous beta-subclass Proteobacteria autotrophic ammonia-oxidizer (beta-AAO) community was assessed. The beta-AAO population abundances were estimated by competitive polymerase chain reaction (PCR) targeting the gene amoA, encoding the alpha-subunit of ammonia monooxygenase. Community structure was examined by PCR and denaturing gradient gel electrophoresis targeting 16S rDNA with band excision and sequence analysis, and by analysis of amoA gene fragment clone libraries. The 16S rDNA analyses showed that a single ribotype of Nitrosospira cluster 3 was the dominant beta-AAO in all treatments. At a finer scale, amoA clone library analysis suggested a shift in community structure corresponding to the 100-ppm application. Competitive PCR indicated significant differences between treatments. The control exhibited relatively stable population abundance over the time period examined. The 10-ppm treatment induced a population increase, but a significant decrease was induced by the 100-ppm application. At 1,000 ppm, the ammonia-oxidizer population dropped below the method detection limit by the first sampling point. An impact on ammonia oxidizers resulting from the application of herbicides was observed, both in abundance and community structure.

Ammonia↗
PubMed2001

Joint acute toxicity of diazinon and ammonia to Ceriodaphnia dubia.

Diazinon is an organophosphorous pesticide widely found in municipal effluents as well as in agricultural and urban storm-water discharges. Ammonia is frequently also present in such effluents as a consequence of bacterial degradation of organic material. Because these two contaminants may occur concurrently, their relationship with respect to joint toxicity is of interest, particularly in regard to interpreting the results of effluent tests and subsequent toxicity identification evaluations (TIEs). In this particular case, we obtained an effluent sample that exhibited toxicity to Ceriodaphnia dubia. Toxicity identification evaluations manipulations suggested that ammonia (40 mg\L as total NH3) and diazinon (0.75 microgram/L) both contributed to toxicity. As part of the Phase 3 confirmation studies, an independent investigation was conducted to evaluate the interactions between these two toxicants using static tests that incorporated a 48-h exposure period. Chemical concentrations were verified analytically. Mortalities were measured at 24-h intervals and joint toxicity calculated on the basis of toxic units (TUs) for each toxicant. The 48-h LC50 values (lethal concentrations for 50% of the population) for the individual chemicals averaged 0.36 microgram/L and 1.11 mg/L for diazinon and un-ionized ammonia, respectively. Under the assumption of strict additivity, the sum of TUs contributed by each toxicant at the LC50 of the mixture should total unity. The TUs associated with the mixtures in laboratory water averaged 1.37 and 1.47, respectively, for 24- and 48-h exposure intervals. These results were similar to those obtained with the actual effluent sample and suggest that diazinon and ammonia exhibit less than additive toxicity when present together.

Ammonia↗
PubMed2004

Constructing a new optical sensor for monitoring ammonia in water samples using bis(acetylacetoneethylendiamine)-tributylphosphin cobalt(III) tetraphenylborate complex-coated triacetylcellulose.

A new ammonia optical sensor was designed using bis(acetylacetoneethylendiamine)tributylphosphin cobalt(III) tetraphenylborate complex, coated on transparent triacetylcellulose film as membrane. The change in the absorbance of the optode at the maximum wavelength of 408 nm was related to ammonia concentration in aqueous samples. A buffer solution with a pH of 9 (sodium borate-HCl) was used. The optode was fully regenerated in pH 2. The linear dynamic range for determination of ammonia was 3.3 x 10(-4) to 6.9 x 10(-3) mol l(-1) with a detection limit of 5.0 x 10(-5) mol l(-1) and a response time range of 4 - 6 min. This membrane was successfully applied for determination of ammonia in drinking water.

Ammonia↗
PubMed2005

Identification of ammonia in gas emanated from human skin and its correlation with that in blood.

Identifying and measuring the ammonia gas that emanates from human skin, which we called skin gas, has been achieved using a modified gas chromatographic system with a nitrogen-selective detector (flame-thermoionic detector: FTD). The skin gas is collected with a home-made sampling probe or bag, which is used to cover the skin surface of a subject's wrist, or a finger, for 5 min. It was proved that ammonia was present in skin gas for healthy persons and patients with hepatic disease. The average amounts of ammonia were 1.7 +/- 0.4 and 2.7 +/- 0.8 ng/cm2; furthermore, there was a significant difference between them (p < 0.05). In addition, the ammonia levels present in skin gas were correlated with that in blood (r = 0.64, p < 0.05).

Ammonia↗
PubMedDate not supplied

Atmospheric ammonia, volatile fatty acids, and other odorants near beef feedlots.

Intensive livestock operations can release odorous gases from stored or land-applied manure. We measured concentrations of dust and 14 odor-causing gases at increasing distances from four feedlots near Lethbridge, southern Alberta, Canada. Concentration was determined from the amount of total dust or gas accumulated in the sampIers, and the volume of air sampled. Adjacent the feedlots, the maximum concentration of many volatile fatty acids exceeded reported odor detection thresholds; the maximum ammonia concentration was close to the threshold. Ammonia and butyric acid approached or exceeded their individual odor thresholds as far as 200 m downwind of the feedlots. Highest concentrations were measured adjacent to land where manure was being applied. None of the odorant concentrations exceeded their irritation threshold. There was a positive relationship between ammonia concentration and odor intensity as well as dry deposition. Much of the emitted ammonia was deposited to soil immediately downwind, enough to supply all the nitrogen needed for crop growth. Odorant concentrations declined sharply with distance, though measurable odor occasionally persisted to 1 km from the feedlot, beyond the minimum separation guidelines (Alberta) for a single residential dwelling. The weekly averaged total suspended particulates (> 5 microm) were below the Alberta guideline criterion except for one period. Differences among feedlots in odorant plume concentrations were partly related to the stocking density of feedlots, which presumably affects manure moisture and amount of volatiles within the pens.

Air Movements↗
PubMedDate not supplied

Ammonia as an indicator of exercise stress implications of recent findings to sports medicine.

The role of ammonia in exercise-induced fatigue is reviewed. Implications for integrated activity of developing hyperammoneic states, caused by various precipitating conditions such as exercise, liver dysfunction, hypoxia, hyperoxia, and chemical poisoning are described. The central role of ammonia in diverse important metabolic pathways indicates its ubiquitous role in a spectrum of activity ranging from elite exhaustive performance of sportsmen and -women to life-threatening organ dysfunction. The action of ammonia and metabolites from associated pathways in producing seemingly dangerous short term conditions, but inducing possible long term protection against degenerative processes associated with ageing (free radical-induced cellular damage) indicate the paradoxical position of ammonia and its associated metabolic pathways for health and disease processes.

Amino Acids↗
PubMed2006

Rule-based fuzzy inference system for estimating the influent COD/N ratio and ammonia load to a sequencing batch reactor.

A fuzzy inference system using sensor measurements was developed to estimate the influent COD/N ratio and ammonia load. The sensors measured ORP, DO and pH. The sensor profiles had a close relationship with the influent COD/N ratio and ammonia load. To confirm this operational knowledge for constructing a rule set, a correlation analysis was conducted. The results showed that a rule generation method based only on operational knowledge did not generate a sufficiently accurate relationship between sensor measurements and target variables. To compensate for this defect, a decision tree algorithm was used as a standardized method for rule generation. Given a set of inputs, this algorithm was used to determine the output variables. However, the generated rules could not estimate the continuous influent COD/N ratio and ammonia load. Fuzzified rules and the fuzzy inference system were developed to overcome this problem. The fuzzy inference system estimated the influent COD/N ratio and ammonia load quite well. When these results were compared to the results from a predictive polynomial neural network model, the fuzzy inference system was more stable.

Algorithms↗
PubMed2006

Effects of dietary humic substances on pig growth performance, carcass characteristics, and ammonia emission.

Five experiments were conducted to test the effects of various dietary humic substances (HS; HS1, 2, 3, and 4, each with different fulvic and humic acid contents) on pig growth, carcass characteristics, and ammonia emission from manure. In Exp. 1, 120 pigs were allotted to 3 dietary treatments without HS (control) or with HS1 at 0.5 and 1.0% (8 pens/treatment and 5 pigs/pen) and fed diets, based on a 5-phase feeding program, from weaning (d 21.3 +/- 0.3 of age) to 60 kg of BW. In Exp. 2 and 3, 384 pigs (192 for each experiment) were allotted to 3 dietary treatments without HS, with HS1, or with HS2 (0.5%) for Exp. 2 and without HS, or with HS3 or HS4 (0.5%) for Exp. 3 (8 pens/treatment and 8 pigs/pen in each experiment). Pigs were fed diets, based on a 6-phase feeding program, from weaning (25.4 +/-0.2 and 23.6 +/-0.3 d of age for Exp. 2 and 3, respectively) to 110 kg of BW. In Exp. 4, 96 pigs were weaned at 22.1 +/-0.2 d of age and allotted to 2 treatments without or with HS1 at 0.5% (6 pens/treatment and 8 pigs/pen), and in Exp. 5 96 pigs were weaned at 20.9 +/-0.3 d of age and allotted to 3 treatments without HS, or with HS3 or HS4 (0.5%; 4 pens/treatment and 8 pigs/pen). Pigs were fed the diets for at least 2 wk before they were moved to an environmental chamber to measure aerial ammonia and hydrogen sulfide for 48 h at 5-min intervals. In Exp. 1, pigs fed diets with HS1 at 0.5% had greater (P < 0.05) ADG during phase 3 and greater (P < 0.05) G:F during phases 3 and 5 than control pigs. In Exp. 2, pigs fed diets with HS1 or HS2 at 0.5% had greater (P < 0.05) ADG and G:F than control pigs during the entire feeding period, whereas in Exp. 3 HS3 or HS4 did not improve pig growth performance. Ammonia emission from manure was reduced by 18 or 16% when pigs were fed diets with HS1 (P = 0.067) or HS4 (P = 0.054), respectively. The results of this study indicate that the effects of dietary HS are variable but may improve growth performance of pigs and reduce ammonia emission from manure. Further research is needed to clarify these effects and the mechanisms by which HS may cause them.

Ammonia↗
PubMed1980

Timed ammonia release for steers.

Slow and rapid ruminal ammonia release rates were simulated by intermittent urea feeding with steers fed winter range grass. Four 360-kg, ruminally-cannulated steers were fed 208 g prairie hay (2.56% crude protein) hourly with the following daily dietary supplements: (1) Urea provided continuously (C) at a rate of 3.5 g/hr for 24 hr; (2) urea provided moderately (M) at a rate of 14.2 g/hr for 6 hr (3) urea offered rapidly (R) as 85 g in 1 hr, or (4) no supplemental urea (O). Ruminal ammonia remained stable with treatments C and O at 12.8 and 1.6 mg/dl, respectively. Treatments R and M peaked 1.5 and 6.5 hr after the start of urea feeding at 41.8 and 37.1 mg/dl, respectively. Nonammonia nitrogen concentrations in the rumen were increased by an average of 23% with urea supplementation. Dry matter digestibility was increased by 5% with addition of urea, regardless of the rate of urea administration. Daily nitrogen retentions were 12.4, 12.2, 11.4 and -7.1 g (P < .01) for C, M, R and O, respectively. Simulated slow ammonia release rates enhanced neither dry matter digestibility nor nitrogen retention. Metabolic use of ammonia in the rumen of steers fed forage was not improved by an attenuated release rate.

Ammonia↗
PubMed1989

Ammonia produced by Campylobacter pylori neutralizes H+ moving through gastric mucus.

We aimed to show that Campylobacter pylori infection increases the concentration of ammonia in the gastric mucus and alters the movement of H+ through the mucus. Mucus from uninfected and C. pylori-infected stomachs was collected at postmortem. Ammonia was measured enzymatically. The ammonia concentration in C. pylori-infected mucus was fourfold greater than in uninfected mucus. H+ movement experiments were carried out using an in vitro chamber, in which a layer of mucus separated a 0.1 M HCl solution from distilled H2O. The change in pH of the distilled H2O was measured over 30 min. A drop in pH was measured for uninfected mucus. A slight rise in pH was measured for C. pylori-infected mucus. We conclude that C. pylori infection is associated with reduced H+ movement through mucus and that this may be due to increased ammonia concentration within mucus.

Ammonia↗
PubMed1991

Blood ammonia concentrations resulting from absorption of irrigating fluid containing glycine and ethanol during transurethral resection of the prostate.

In 30 patients the blood ammonia concentration was measured 30 min was after transurethral resection of the prostate during which absorption of irrigating fluid containing 1.5% of glycine and 1% of ethanol had been indicated by serial expired breath tests. The volume of irrigating fluid that had been absorbed was either measured volumetrically (n = 25) or estimated from the ethanol concentration in the expired breath (n = 5); the median volume of irrigating fluid absorbed was 1.3 litres (range 0.2-4.3). There was no consistent rise in the blood ammonia concentration, nor was there any correlation between the blood ammonia concentration and the volume of irrigating fluid absorbed. No patient developed symptoms that could be clearly related to hyperammonaemic glycine toxicity, but 18 of the 30 patients developed other signs of the "TURP syndrome". The present results suggest that irrigating fluid containing both glycine and ethanol does not significantly increase blood ammonia concentration or produce symptoms of glycine toxicity.

Absorption↗
PubMed1987

Age-related changes in muscle ammonia detoxification potential in exhausted rats.

The changes in the pattern of production and detoxification of ammonia have been studied in the skeletal muscles and blood of rats of different age groups (1, 3, 6, 12 and 24 months), subjected to exhaustive exercise. The protein profiles at exhaustion showed a sharp drop in all muscles and the decrement was more in the senile rats. In general, the muscle and blood ammonia content increased with age with a corresponding increase in AMP deaminase activity implicating the possibility of elevated purine nucleotide deamination during senescence. However, glutamate oxidation was decreased and urea and glutamine formation was increased consequent to ammonia production during senescence under intensive physical stress. The possible alterations in protein levels and ammonia production and its disposal in different skeletal muscle types of senile exhausted rats have been discussed in relation to detoxication capacity of the fibre types.

AMP Deaminase↗
PubMed1976

Effect of urea form and method of feeding on rumen ammonia concentration.

Rumen ammonia was compared in six rumen fistulated, lactating Holstein cows fed urea twice daily in a concentrate mixture, urea fed once per day in a complete ration, and a gelatinized starch-urea product fed twice daily in the concentrate mixture. Samples were taken during 24-h intervals at the end of each 3 wk. Sharp and similar peaks in rumen ammonia followed feeding of urea and gelatinized urea-starch product twice daily in the concentrate mixture. A much lower ammonia peak followed the once daily feeding of the complete ration. Use of complete rations offered ad libitum eliminates the need for products with sustained ammonia release.

Ammonia↗
PubMed1999

Short communication: the effect of duodenal ammonia infusions on milk production and nitrogen balance of the dairy cow.

We hypothesized that an increased uptake of ammonia from the gut of dairy cows would increase the use of amino acids for urea synthesis and decrease the availability of amino acids for milk protein production, leading to a reduction in milk protein output. To test this hypothesis, four multiparous Holstein-Friesian dairy cows offered a constant diet based on grass silage were continuously infused with ammonium acetate (ammonia) or acetic acid (control) into the duodenum for 5 d in each period of a changeover design experiment. Silage intake, rumen ammonia, pH and volatile fatty acid concentrations, and feces N excretion and whole body N balance were all unaffected by treatment, although urinary N excretion increased. Similarly, there was no effect of treatment on milk yields or on milk constituent yields. We concluded that ammonia absorption represents a loss of protein to the animal, but that it is unlikely to result in reduced amino acid availability for productive purposes such as lactation.

Ammonia↗
PubMed1982

Effect of atmospheric ammonia on laying hen performance.

In periods of extremely cold weather, energy conservation in a pit-type laying house usually results in a restricted ventilation rate and an increase in air pollutants particularly ammonia. Results show that 200 ppm ammonia for 17 days causes a significant loss in percent egg production and the hens lose a significant amount of weight with a reduced feed intake. Although not satisfactory, it appears that lesser amounts of ammonia (100 ppm) can be tolerated for short periods without an immediate drastic loss in laying performance if a choice has to be made between frozen waterers and cold stress versus atmospheric ammonia in the laying house.

Ammonia↗
PubMed1991

The effect of different levels of relative humidity and air movement on litter conditions, ammonia levels, growth, and carcass quality for broiler chickens.

An experiment using 4,800 commercial broiler males (Ross x Ross) was conducted in 12 climatic chambers. Three levels of relative humidity (RH) (45, 40, to 80, and 75%) and two levels of internal air circulation (7.7 to 9.9 and 17.8 to 24.5 cm/s), with each level replicated and, therefore, forming a 3 x 2 x 2 factorial arrangement of treatments, arrangement of treatments, were imposed as the main effects. Broilers were group weighed and feed efficiencies calculated at 14, 28, and 42 days of age. Percentage dry matter of the litter and a subjective evaluation of general litter conditions (moisture and caking) were scored weekly, with the percentage nitrogen and total quality of litter produced in each chamber measured at the conclusion of the study. Ammonia levels were measured in each chamber every second day. A sample of birds (36) from each chamber was processed at 42 days and scored for litter spots and ammonia burns on the breast and for the incidence and severity of twisted legs, crooked toes, and infected and calloused hocks and foot pads. Mean body weight was significantly greater (32 g) at 42 days of age in birds exposed to 45% RH compared with the two higher regimens of RH. Both the incidence and severity of ammonia burns on the breast and infected foot pads were significantly higher with 75 versus 45% RH. Increases in RH significantly increased caking and litter moisture and reduced the percentage of dry matter and the percentage of nitrogen found in the litter. Ammonia levels were more variable but generally increased with increases in RH. The two levels of air movement within the chambers produced less influence on the environment than RH, although the scores for both litter moisture and caking were significantly lower with increased levels of internal air circulation.

Air Movements↗
PubMed2004

An outbreak of ammonia poisoning from chicken tenders served in a school lunch.

Although foodborne outbreaks of illness are relatively common, they are rarely caused by chemical agents. An outbreak of gastrointestinal illness occurred among students at two schools shortly after lunch was served. A cohort study, an environmental investigation, and microbiological and toxicological laboratory testing of food samples were performed. A case was defined as a student or teacher who ate food prepared in the kitchen at school A on 25 November 2002 (and served at schools A and B) and who later developed headache or symptoms of gastrointestinal tract irritation, with onset within 180 min of eating lunch. Among 312 persons interviewed, 157 persons became ill (attack rate = 49%; attack rate 41% for school A, 11% for school B). Onset of illness occurred within 60 min for 81% of cases; 91% of students reported that their chicken tenders smelled unusual. Eating chicken tenders that smelled unusual was associated with being a case (relative risk 9.2, 95% confidence interval 1.4 to 62.6, P < 0.05). Ammonia was detected in uncooked chicken tenders at levels as high as 2,468 ppm. The chicken had been contaminated during a warehouse leak of ammonia refrigerant. This outbreak of ammonia poisoning is only the second reported in food, and the first in a solid food. Heated chicken tenders contaminated with ammonia can cause acute illness within a short period of time.

Adolescent↗
PubMed1998

Müller (glial) cell development in vivo and in retinal explant cultures: morphology and electrophysiology, and the effects of elevated ammonia.

Retinal explant cultures have been established as a useful tool to study both the normal development of the mammalian retina and the effects of pathogenic agents. We used such cultures as a model for the (ammonia-induced) hepatic retinopathy, earlier observed in humans with chronical liver failure, and ascribed to a breakdown of Müller (glial) cell function. In the explant cultures, one day exposure to elevated (7 mM) ammonia was sufficient to cause Müller cell reactivity as indicated by increasing immunopositivity for glial fibrillary acidic protein. After 4 days in elevated ammonia, the Müller cells were severely deformed, the layered structure of the retinae became disorganized, and significant neuronal cell death occurred. Using whole-cell voltage-clamp recordings, the expression of K+ channels was compared in Müller cells isolated from retinae of rabbits at postnatal days 9 to 12 and from neonatal explants cultured for 9 to 12 days, respectively. Müller glial cells grown both in vivo and in vitro express the same set of K+ channels in their membranes: (i) inwardly rectifying K+ (K(IR)) channels which were selectively blocked by Ba2+ ions; (ii) large-conductance, Ca2+-activated K+ (BK(Ca)) channels which were blocked by iberiotoxin and were activated by phloretin; and (iii) delayed rectifying voltage-gated K+ channels. The presence of K(IR) channels indicates successful differentiation of the Müller cells grown in vitro, as these channels are not expressed in cells from neonatal animals. Four days of elevated ammonia in the culture medium caused a complete loss of K(IR) channels in Müller cell membranes, and a significant decrease of the membrane potential. The results indicate that in hepatic retinopathy, the well-known morphological and enzymatical alterations of Müller glial cells may be accompanied by changes in their membrane permeability for K+.

4-Aminopyridine↗