Reaction Process: BioCyc:META_PWY-5727

atrazine degradation II related metabolites

find 7 related metabolites which is associated with chemical reaction(pathway) atrazine degradation II

A(H2) + O2 + atrazine ⟶ A + H2O + acetone + deethylsimazine

atrazine

6-chloro-N2-ethyl-N4-(1-methylethyl)-1,3,5-triazine-2,4,-diamine

C8H14ClN5 (215.0937674)


A diamino-1,3,5-triazine that is 1,3,5-triazine-2,4-diamine substituted by a chloro group at position 6 while one of hydrogens of each amino group is replaced respectively by an ethyl and a propan-2-yl group. D010575 - Pesticides > D006540 - Herbicides D016573 - Agrochemicals CONFIDENCE standard compound; INTERNAL_ID 718; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 8568; ORIGINAL_PRECURSOR_SCAN_NO 8565 CONFIDENCE standard compound; INTERNAL_ID 718; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 8581; ORIGINAL_PRECURSOR_SCAN_NO 8579 CONFIDENCE standard compound; INTERNAL_ID 718; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 8572; ORIGINAL_PRECURSOR_SCAN_NO 8570 CONFIDENCE standard compound; INTERNAL_ID 718; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 8520; ORIGINAL_PRECURSOR_SCAN_NO 8518 CONFIDENCE standard compound; INTERNAL_ID 718; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 8527; ORIGINAL_PRECURSOR_SCAN_NO 8525 CONFIDENCE standard compound; INTERNAL_ID 718; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 8492; ORIGINAL_PRECURSOR_SCAN_NO 8489 CONFIDENCE standard compound; EAWAG_UCHEM_ID 288 CONFIDENCE standard compound; INTERNAL_ID 4033 CONFIDENCE standard compound; INTERNAL_ID 3109 CONFIDENCE standard compound; INTERNAL_ID 8414 CONFIDENCE standard compound; INTERNAL_ID 29

   

6-Chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine

6-chloro-N-(1-Methylethyl)-1,3,5-triazine-2,4-diamine, 9ci

C6H10ClN5 (187.06246900000002)


CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7123; ORIGINAL_PRECURSOR_SCAN_NO 7121 CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7114; ORIGINAL_PRECURSOR_SCAN_NO 7112 CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7136; ORIGINAL_PRECURSOR_SCAN_NO 7132 CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7127; ORIGINAL_PRECURSOR_SCAN_NO 7125 CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7139; ORIGINAL_PRECURSOR_SCAN_NO 7137 CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7129; ORIGINAL_PRECURSOR_SCAN_NO 7127 6-Chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine is a major soil metabolite of Atrazine DKW85-F. Environmental pollutant of soil and water. Major soil metabolite of Atrazine DKW85-F. Environmental pollutant of soil and water. CONFIDENCE standard compound; EAWAG_UCHEM_ID 309 CONFIDENCE standard compound; INTERNAL_ID 4025 INTERNAL_ID 3016; CONFIDENCE standard compound CONFIDENCE standard compound; INTERNAL_ID 8408 CONFIDENCE standard compound; INTERNAL_ID 3016 CONFIDENCE standard compound; INTERNAL_ID 2537

   

Deisopropylatrazine

6-chloro-N2-ethyl-1,3,5-triazine-2,4-diamine

C5H8ClN5 (173.04681979999998)


CONFIDENCE standard compound; INTERNAL_ID 140; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 6172; ORIGINAL_PRECURSOR_SCAN_NO 6168 CONFIDENCE standard compound; INTERNAL_ID 140; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 6175; ORIGINAL_PRECURSOR_SCAN_NO 6173 CONFIDENCE standard compound; INTERNAL_ID 140; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 6181; ORIGINAL_PRECURSOR_SCAN_NO 6180 CONFIDENCE standard compound; INTERNAL_ID 140; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 6202; ORIGINAL_PRECURSOR_SCAN_NO 6200 CONFIDENCE standard compound; INTERNAL_ID 140; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 6192; ORIGINAL_PRECURSOR_SCAN_NO 6191 CONFIDENCE standard compound; EAWAG_UCHEM_ID 287 CONFIDENCE standard compound; INTERNAL_ID 2539 CONFIDENCE standard compound; INTERNAL_ID 3726 CONFIDENCE standard compound; INTERNAL_ID 4030 CONFIDENCE standard compound; INTERNAL_ID 8411 KEIO_ID A203

   

Acetone

Dimethylformaldehyde

C3H6O (58.041862599999995)


Acetone, or propanone, is an organic compound with the formula (CH3)2CO. It is the simplest and smallest ketone. It is a colourless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscible with water and serves as an important organic solvent in its own right, in industry, home, and laboratory. Acetone is produced and disposed of in the human body through normal metabolic processes. It is normally present in blood and urine. People with diabetic ketoacidosis produce it in larger amounts. Acetone is not regarded as a waste product of metabolism. However, its physiological role in biochemical machinery is not clear. A model for the role of acetone metabolism is presented that orders the events occurring in acetonemia in sequence: in diabetic ketosis or starvation, ketone body production (b-hydroxy-butyrate, acetoacetate) provides fuel for vital organs (heart, brain, among others) raising the chance of survival of the metabolic catastrophe. However, when ketone body production exceeds the degrading capacity, the accumulating acetoacetic acid presents a new challenge to the pH regulatory system. Acetone production and its further degradation to C3 fragments fulfill two purposes: the maintenance of pH buffering capacity and provision of fuel for peripheral tissues. Since ketosis develops under serious metabolic circumstances, all the mechanisms that balance or moderate the effects of ketosis enhance the chance for survival. From this point of view, the theory that transportable C3 fragments can serve as additional nutrients is a novel view of acetone metabolism which introduces a new approach to the study of acetone degradation, especially in understanding its physiological function and the interrelationship between liver and peripheral tissues. (PMID 10580530). Acetone is typically derived from acetoacetate through the action of microbial acetoacetate decarboxylases found in gut microflora. In chemistry, acetone is the simplest representative of the ketones. Acetone is a colorless, mobile, flammable liquid readily soluble in water, ethanol, ether, etc., and itself serves as an important solvent. It is an irritant and inhalation may lead to hepatotoxic effects (causing liver damage). Acetone can be found in Clostridium (PMID:685531). Solvent used in food processing as a colour diluent, flavour ingredient, etc. D012997 - Solvents

   

Water

oxidane

H2O (18.0105642)


Water is a chemical substance that is essential to all known forms of life. It appears colorless to the naked eye in small quantities, though it is actually slightly blue in color. It covers 71\\% of Earths surface. Current estimates suggest that there are 1.4 billion cubic kilometers (330 million m3) of it available on Earth, and it exists in many forms. It appears mostly in the oceans (saltwater) and polar ice caps, but it is also present as clouds, rain water, rivers, freshwater aquifers, lakes, and sea ice. Water in these bodies perpetually moves through a cycle of evaporation, precipitation, and runoff to the sea. Clean water is essential to human life. In many parts of the world, it is in short supply. From a biological standpoint, water has many distinct properties that are critical for the proliferation of life that set it apart from other substances. It carries out this role by allowing organic compounds to react in ways that ultimately allow replication. All known forms of life depend on water. Water is vital both as a solvent in which many of the bodys solutes dissolve and as an essential part of many metabolic processes within the body. Metabolism is the sum total of anabolism and catabolism. In anabolism, water is removed from molecules (through energy requiring enzymatic chemical reactions) in order to grow larger molecules (e.g. starches, triglycerides and proteins for storage of fuels and information). In catabolism, water is used to break bonds in order to generate smaller molecules (e.g. glucose, fatty acids and amino acids to be used for fuels for energy use or other purposes). Water is thus essential and central to these metabolic processes. Water is also central to photosynthesis and respiration. Photosynthetic cells use the suns energy to split off waters hydrogen from oxygen. Hydrogen is combined with CO2 (absorbed from air or water) to form glucose and release oxygen. All living cells use such fuels and oxidize the hydrogen and carbon to capture the suns energy and reform water and CO2 in the process (cellular respiration). Water is also central to acid-base neutrality and enzyme function. An acid, a hydrogen ion (H+, that is, a proton) donor, can be neutralized by a base, a proton acceptor such as hydroxide ion (OH-) to form water. Water is considered to be neutral, with a pH (the negative log of the hydrogen ion concentration) of 7. Acids have pH values less than 7 while bases have values greater than 7. Stomach acid (HCl) is useful to digestion. However, its corrosive effect on the esophagus during reflux can temporarily be neutralized by ingestion of a base such as aluminum hydroxide to produce the neutral molecules water and the salt aluminum chloride. Human biochemistry that involves enzymes usually performs optimally around a biologically neutral pH of 7.4. (Wikipedia). Water, also known as purified water or dihydrogen oxide, is a member of the class of compounds known as homogeneous other non-metal compounds. Homogeneous other non-metal compounds are inorganic non-metallic compounds in which the largest atom belongs to the class of other nonmetals. Water can be found in a number of food items such as caraway, oxheart cabbage, alaska wild rhubarb, and japanese walnut, which makes water a potential biomarker for the consumption of these food products. Water can be found primarily in most biofluids, including ascites Fluid, blood, cerebrospinal fluid (CSF), and lymph, as well as throughout all human tissues. Water exists in all living species, ranging from bacteria to humans. In humans, water is involved in several metabolic pathways, some of which include cardiolipin biosynthesis CL(20:4(5Z,8Z,11Z,14Z)/18:0/20:4(5Z,8Z,11Z,14Z)/18:2(9Z,12Z)), cardiolipin biosynthesis cl(i-13:0/i-15:0/i-20:0/i-24:0), cardiolipin biosynthesis CL(18:0/18:0/20:4(5Z,8Z,11Z,14Z)/22:5(7Z,10Z,13Z,16Z,19Z)), and cardiolipin biosynthesis cl(a-13:0/i-18:0/i-13:0/i-19:0). Water is also involved in several metabolic disorders, some of which include de novo triacylglycerol biosynthesis tg(i-21:0/i-13:0/21:0), de novo triacylglycerol biosynthesis tg(22:0/20:0/i-20:0), de novo triacylglycerol biosynthesis tg(a-21:0/i-20:0/i-14:0), and de novo triacylglycerol biosynthesis tg(i-21:0/a-17:0/i-12:0). Water is a drug which is used for diluting or dissolving drugs for intravenous, intramuscular or subcutaneous injection, according to instructions of the manufacturer of the drug to be administered [fda label]. Water plays an important role in the world economy. Approximately 70\\% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a major source of food for many parts of the world. Much of long-distance trade of commodities (such as oil and natural gas) and manufactured products is transported by boats through seas, rivers, lakes, and canals. Large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a wide variety of chemical substances; as such it is widely used in industrial processes, and in cooking and washing. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, and diving .

   

Oxygen

Molecular oxygen

O2 (31.98983)


Oxygen is the third most abundant element in the universe after hydrogen and helium and the most abundant element by mass in the Earths crust. Diatomic oxygen gas constitutes 20.9\\% of the volume of air. All major classes of structural molecules in living organisms, such as proteins, carbohydrates, and fats, contain oxygen, as do the major inorganic compounds that comprise animal shells, teeth, and bone. Oxygen in the form of O2 is produced from water by cyanobacteria, algae and plants during photosynthesis and is used in cellular respiration for all living organisms. Green algae and cyanobacteria in marine environments provide about 70\\% of the free oxygen produced on earth and the rest is produced by terrestrial plants. Oxygen is used in mitochondria to help generate adenosine triphosphate (ATP) during oxidative phosphorylation. For animals, a constant supply of oxygen is indispensable for cardiac viability and function. To meet this demand, an adult human, at rest, inhales 1.8 to 2.4 grams of oxygen per minute. This amounts to more than 6 billion tonnes of oxygen inhaled by humanity per year. At a resting pulse rate, the heart consumes approximately 8-15 ml O2/min/100 g tissue. This is significantly more than that consumed by the brain (approximately 3 ml O2/min/100 g tissue) and can increase to more than 70 ml O2/min/100 g myocardial tissue during vigorous exercise. As a general rule, mammalian heart muscle cannot produce enough energy under anaerobic conditions to maintain essential cellular processes; thus, a constant supply of oxygen is indispensable to sustain cardiac function and viability. However, the role of oxygen and oxygen-associated processes in living systems is complex, and they and can be either beneficial or contribute to cardiac dysfunction and death (through reactive oxygen species). Reactive oxygen species (ROS) are a family of oxygen-derived free radicals that are produced in mammalian cells under normal and pathologic conditions. Many ROS, such as the superoxide anion (O2-)and hydrogen peroxide (H2O2), act within blood vessels, altering mechanisms mediating mechanical signal transduction and autoregulation of cerebral blood flow. Reactive oxygen species are believed to be involved in cellular signaling in blood vessels in both normal and pathologic states. The major pathway for the production of ROS is by way of the one-electron reduction of molecular oxygen to form an oxygen radical, the superoxide anion (O2-). Within the vasculature there are several enzymatic sources of O2-, including xanthine oxidase, the mitochondrial electron transport chain, and nitric oxide (NO) synthases. Studies in recent years, however, suggest that the major contributor to O2- levels in vascular cells is the membrane-bound enzyme NADPH-oxidase. Produced O2- can react with other radicals, such as NO, or spontaneously dismutate to produce hydrogen peroxide (H2O2). In cells, the latter reaction is an important pathway for normal O2- breakdown and is usually catalyzed by the enzyme superoxide dismutase (SOD). Once formed, H2O2 can undergo various reactions, both enzymatic and nonenzymatic. The antioxidant enzymes catalase and glutathione peroxidase act to limit ROS accumulation within cells by breaking down H2O2 to H2O. Metabolism of H2O2 can also produce other, more damaging ROS. For example, the endogenous enzyme myeloperoxidase uses H2O2 as a substrate to form the highly reactive compound hypochlorous acid. Alternatively, H2O2 can undergo Fenton or Haber-Weiss chemistry, reacting with Fe2+/Fe3+ ions to form toxic hydroxyl radicals (-.OH). (PMID: 17027622, 15765131) [HMDB]. Oxygen is found in many foods, some of which are soy bean, watermelon, sweet basil, and spinach. Oxygen is the third most abundant element in the universe after hydrogen and helium and the most abundant element by mass in the Earths crust. Diatomic oxygen gas constitutes 20.9\\% of the volume of air. All major classes of structural molecules in living organisms, such as proteins, carbohydrates, and fats, contain oxygen, as do the major inorganic compounds that comprise animal shells, teeth, and bone. Oxygen in the form of O2 is produced from water by cyanobacteria, algae and plants during photosynthesis and is used in cellular respiration for all living organisms. Green algae and cyanobacteria in marine environments provide about 70\\% of the free oxygen produced on earth and the rest is produced by terrestrial plants. Oxygen is used in mitochondria to help generate adenosine triphosphate (ATP) during oxidative phosphorylation. For animals, a constant supply of oxygen is indispensable for cardiac viability and function. To meet this demand, an adult human, at rest, inhales 1.8 to 2.4 grams of oxygen per minute. This amounts to more than 6 billion tonnes of oxygen inhaled by humanity per year. At a resting pulse rate, the heart consumes approximately 8-15 ml O2/min/100 g tissue. This is significantly more than that consumed by the brain (approximately 3 ml O2/min/100 g tissue) and can increase to more than 70 ml O2/min/100 g myocardial tissue during vigorous exercise. As a general rule, mammalian heart muscle cannot produce enough energy under anaerobic conditions to maintain essential cellular processes; thus, a constant supply of oxygen is indispensable to sustain cardiac function and viability. However, the role of oxygen and oxygen-associated processes in living systems is complex, and they and can be either beneficial or contribute to cardiac dysfunction and death (through reactive oxygen species). Reactive oxygen species (ROS) are a family of oxygen-derived free radicals that are produced in mammalian cells under normal and pathologic conditions. Many ROS, such as the superoxide anion (O2-)and hydrogen peroxide (H2O2), act within blood vessels, altering mechanisms mediating mechanical signal transduction and autoregulation of cerebral blood flow. Reactive oxygen species are believed to be involved in cellular signaling in blood vessels in both normal and pathologic states. The major pathway for the production of ROS is by way of the one-electron reduction of molecular oxygen to form an oxygen radical, the superoxide anion (O2-). Within the vasculature there are several enzymatic sources of O2-, including xanthine oxidase, the mitochondrial electron transport chain, and nitric oxide (NO) synthases. Studies in recent years, however, suggest that the major contributor to O2- levels in vascular cells is the membrane-bound enzyme NADPH-oxidase. Produced O2- can react with other radicals, such as NO, or spontaneously dismutate to produce hydrogen peroxide (H2O2). In cells, the latter reaction is an important pathway for normal O2- breakdown and is usually catalyzed by the enzyme superoxide dismutase (SOD). Once formed, H2O2 can undergo various reactions, both enzymatic and nonenzymatic. The antioxidant enzymes catalase and glutathione peroxidase act to limit ROS accumulation within cells by breaking down H2O2 to H2O. Metabolism of H2O2 can also produce other, more damaging ROS. For example, the endogenous enzyme myeloperoxidase uses H2O2 as a substrate to form the highly reactive compound hypochlorous acid. Alternatively, H2O2 can undergo Fenton or Haber-Weiss chemistry, reacting with Fe2+/Fe3+ ions to form toxic hydroxyl radicals (-.OH). (PMID: 17027622, 15765131). V - Various > V03 - All other therapeutic products > V03A - All other therapeutic products > V03AN - Medical gases

   

Acetaldehyde

Acetic aldehyde

C2H4O (44.0262134)


Acetaldehyde, also known as ethanal, belongs to the class of organic compounds known as short-chain aldehydes. These are an aldehyde with a chain length containing between 2 and 5 carbon atoms. Acetaldehyde exists in all living species, ranging from bacteria to humans. Within humans, acetaldehyde participates in a number of enzymatic reactions. In particular, acetaldehyde can be biosynthesized from ethanol which is mediated by the enzyme alcohol dehydrogenase 1B. Acetaldehyde can also be converted to acetic acid by the enzyme aldehyde dehydrogenase (mitochondrial) and aldehyde dehydrogenase X (mitochondrial). The main method of production is the oxidation of ethylene by the Wacker process, which involves oxidation of ethylene using a homogeneous palladium/copper system: 2 CH2CH2 + O2 → 2 CH3CHO. In the 1970s, the world capacity of the Wacker-Hoechst direct oxidation process exceeded 2 million tonnes annually. In humans, acetaldehyde is involved in disulfiram action pathway. Acetaldehyde is an aldehydic, ethereal, and fruity tasting compound. Outside of the human body, acetaldehyde is found, on average, in the highest concentration in a few different foods, such as sweet oranges, pineapples, and mandarin orange (clementine, tangerine) and in a lower concentration in . acetaldehyde has also been detected, but not quantified in several different foods, such as malabar plums, malus (crab apple), rose hips, natal plums, and medlars. This could make acetaldehyde a potential biomarker for the consumption of these foods. In condensation reactions, acetaldehyde is prochiral. Acetaldehyde is formally rated as a possible carcinogen (by IARC 2B) and is also a potentially toxic compound. Acetaldehyde has been found to be associated with several diseases such as alcoholism, ulcerative colitis, nonalcoholic fatty liver disease, and crohns disease; also acetaldehyde has been linked to the inborn metabolic disorders including aldehyde dehydrogenase deficiency (III) sulfate is used to reoxidize the mercury back to the mercury. Acetaldehyde was first observed by the Swedish pharmacist/chemist Carl Wilhelm Scheele (1774); it was then investigated by the French chemists Antoine François, comte de Fourcroy and Louis Nicolas Vauquelin (1800), and the German chemists Johann Wolfgang Döbereiner (1821, 1822, 1832) and Justus von Liebig (1835). At room temperature, acetaldehyde (CH3CHO) is more stable than vinyl alcohol (CH2CHOH) by 42.7 kJ/mol: Overall the keto-enol tautomerization occurs slowly but is catalyzed by acids. The level at which an average consumer could detect acetaldehyde is still considerably lower than any toxicity. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Acetaldehyde is also created by thermal degradation or ultraviolet photo-degradation of some thermoplastic polymers during or after manufacture. The water industry generally recognizes 20–40 ppb as the taste/odor threshold for acetaldehyde. The level at which an average consumer could detect acetaldehyde is still considerably lower than any toxicity. Flavouring agent and adjuvant used to impart orange, apple and butter flavours; component of food flavourings added to milk products, baked goods, fruit juices, candy, desserts and soft drinks [DFC]