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Acrylamide: Contamination in Water and an Assessment of Regulations. and diffuse intrusions of macrophages and chromosomal aberrations-clastrogenesis (Larguinho.

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Presentation on theme: "Acrylamide: Contamination in Water and an Assessment of Regulations. and diffuse intrusions of macrophages and chromosomal aberrations-clastrogenesis (Larguinho."— Presentation transcript:

1 Acrylamide: Contamination in Water and an Assessment of Regulations. and diffuse intrusions of macrophages and chromosomal aberrations-clastrogenesis (Larguinho et al. 2014). Marine organisms - Mytilus galloprovincialis (mussels) resembled mammalian GST metabolic activities and exhibited cell necrosis of gonads and oocyte atresia (Larguinho et al.2014). Jasmeet Kaur, Laura Smolyar and Antonio F. Machado Department of Environmental and Occupational Health, California State University, Northridge. Abstract Introduction Industrial Production and Uses Fate and Transport Levels in the Environmental Matrices Metabolism Health Effects Regulations Remediation/Recommendations Ecotoxicology/Ecology Conclusion References Routes of exposure Mandeep K. Virk-Baker, Tim R. Nagy, Stephen Barnes & John Groopman. 2014. Dietary Acrylamide and Human Cancer: A Systematic Review of Literature. Nutrition and Cancer 66:5, 774-790. US EPA O. 2014. Drinking water contaminants. In: National primary drinking water regulations:NC:U.S Environmental Protection Agency. State of California EPA. 2014. Safe drinking water and toxic enforcement act of 1986. In: Proposition 65, Case. 79-06-1. California:Office of Environmental Health Hazzard Assessment. Dybinga PBF, M. Andersen et. 2005. Human exposure and internal dose assessments of acrylamide in food. 43:365–410. Solene Touze VG, Anne-Gwenaelle Guezennec, Stephane Binet, Anne Togola. 2014. Dissemination of acrylamide monomer from polyacrylamide-based flocculant use-sand and gravel quarry case study. Environmental Science Pollution Res. Lande SS, Bosch, Stephen J., Howard, Philip H. 2014. Degradation and leaching of acrylamide in soul. JOENG:133-137. Taeymans D, Wood J, Ashby P, Blank I, Studer A, Stadler RH, et al. 2004. A review of acrylamide: An industry perspective on research, analysis, formation, and control. Crit Rev Food Sci Nutr 44:323-347. Brown L, Rhead MM, Hill D, Bancroft KCC. 1982. Qualitative and quantitative studies on the in situ adsorption, degradation and toxicity of acrylamide by the spiking of the waters of two sewage works and a river. Water Res 16(5): 579-591. States FaAOotU. 2010. Joint fao/who expert committee on food additives. Rome, Italy:World Health Organization. Centre Ecjr. 2014. Eurpean union risk assessment report acrylamide. Italy:European Union. Stadler RH, Blank I, Varga N, Robert F, Hau J, Guy PA, et al. 2002. Food chemistry: Acrylamide from maillard reaction products. Nature 419:449-450. Mottram DS, Wedzicha BL, Dodson AT. 2002. Food chemistry: Acrylamide is formed in the maillard reaction. Nature 419:448-449. Gertz C, Klostermann S. 2014. Analysis of acrylamide and mechanisms of its formation in deep‐fried products. TAEYMANS D, WOOD J, ASHBY P, BLANK I, STUDER A, STADLER RH, et al. 2010. A review of acrylamide: An industry perspective on research, analysis, formation, and control. http://dxdoiorg/101080/10408690490478082. Skog K, Viklund G, Olsson K, Sjoholm I. 2008. Acrylamide in home-prepared roasted potatoes. Mol Nutr Food Res 52:307-312. Tareke E, Rydberg P, Karlsson P, Eriksson S, Tornqvist M. 2002. Analysis of acrylamide, a carcinogen formed in heated foodstuffs. J Agric Food Chem 50:4998-5006. Mojska H, Gielecinska I, Szponar L. 2007. Acrylamide content in heat-treated carbohydrate-rich foods in poland. Rocz Panstw Zakl Hig 58:345-349. Franco Pedreschi MSM, Kit Granby. 2014. Current issues in dietary acrylamide: Formation, mitigation and risk assessment. Journal of the Science of Food and Agriculture 94:9-20. EPA. 2009. Contaminant occurrence support document for 2nd 6-year review category 1 contaminants. US EPA O. 2013. Basic information about acrylamide in drinking water. Available: http://water.epa.gov/drink/contaminants/basicinformation/acrylamide.cfm. Anne Togola CC, Anne-Gwenaelli Guezennec, Solene Touze. 2014. A sensitive analytical procedure for monitoring acrylamide in environm. C.J Calleman YW, F. He, G. Tian, E. Bergmark, S. Zhang, H. Deng, Y. Wang, K.M. Crofton, T. Fennell, L.G Costa. 1994. Relationships between biomarkers of exposure and neurological effects in a group of workers exposed to acrylamide. 126:361–371. Junqua G, Spinelli S, Gonzalez C. 2014. Occurrence and fate of acrylamide in water-recycling systems and sludge in aggregate industries. Environ Sci Pollut Res Int. EPA US. 2014. Drinking water treatment. Available: http://water.epa.gov/lawsregs/guidance/sdwa/upload/2009_08_28_sdwa_fs_30ann_treatment_web.pdf. Charoenpanich J. 2014. Removal of acrylamide by microorganisms. Department of Biochemistry, Faculty of Science, Burapha University, Bangsaen, Chonburi,. Acrylamide Production in Food Acrylamide distribution in the body circulates compartments depending on the exposure route. Ingested acrylamide travels into the stomach, then into liver. Liver cells hepatocytes metabolize acrylamide via pathways described in Fig.1. Metabolite of acrylamide glycidamide, may get recirculated back into the system. Intravenous blood carries compounds to the lungs, and lungs bring them back into arterial blood supply. Blood takes compounds into tissues and back into the liver. In humans, half-life of acrylamide in the plasma is short, Half- life of acrylamide in rodents ranges from 1-4 hours (Sumner et al. 1992). In a study conducted on human population exposed to acrylamide, biomarkers are used to determine exposures. Urinary excretion of acrylamide metabolites had been noted. There is a positive significant correlation between the metabolites located in the urine of exposed humans and the neurotoxicity index, as well as acrylamide hemoglobin adducts to N-terminal valine (C.J Calleman 1994). Smokers were evaluated based on the urine and blood samples, vs the non-smokers. Mercapturic acid (N-acetyl-S-(2- carbamoylethyl)-L-cysteine, AAMA) increased by 2.5 folds, metabolites of glycidamide (N-(R/S)-acetyl-S-(2-carbamoyl-2- hydroxyethyl)-L-cysteine, GAMA) increase by 1.7 folds, the N- terminal valine adduct of acrylamide (N-2- carbamoylethylvaline, AAVal) in blood increase by 3 fold in smokers (Urban et al. 2008). Nervous system effects: Negative effects on the nervous system are not generally noticeable in a large population exposed to lower doses of acrylamide. Study of workers exposed to acrylamide via inhalation found that 71% experienced numbness in extremities and fatigue, 68% experienced sweating of hands and feet, 59% skin peeling, 54% loss of pain sensations and 46% loss of touch sensations. Less than 50% of workers experienced dizziness, anorexia, loss of vibration sensation, nausea, loss of ankle reflexes, headaches, and unsteady gait (C.J Calleman 1994). Reproductive effects Study was conducted on mice affected by obesity and acrylamide. Obesity had reduced fertility of male mice, but even further potentiated acrylamide induced toxicity that lead to even greater infertility, acrylamide effected both obese and lean males. Obese males displayed greater susceptibility to potentiation of acrylamide induced infertility than lean males. The relationship between diet induced obesity and acrylamide toxicity was linked to decreased fertility, parameters as abnormal sperm morphology and low total sperm count (Ghanayem et al. 2010). Cancer Various cohort-studies have been conducted on humans to evaluate acrylamide’s carcinogenic effects, and produced some inconclusive data. A study about endometrial cancer (EC) concluded that there were no EC risk associated for women with dietary acrylamide intake, however an increased risk for EC was noted for women who were non- smokers and were not treated with oral contraceptives. Human cancer risk assessments are still estimated, through a physiologically based pharmacokinetic and pharmacodynamics (PBPK/PD) model. One such model had estimated risk to be 1-4 in 10 thousand will be affected by cancer, with the average daily consumption dose of acrylamide (Doerge et al. 2008). Studies show that there is a statistically significant correlation between acrylamide exposure and rodent carcinogenicity. It is important to note that carcinogenicity of acrylamide in rodent studies displayed affinity for reproductive system organs adverse effects. Acrylamide and it’s metabolite glycidamide are both considered to have mutagenic properties, however glycidamide is assumed to be a more potent carcinogen. Endocrine system disruption Endocrine system disruptions are disruptions in the hormone regulations, caused by low doses of acrylamide. Thyroid gland effects of decreased in the colloid area and follicular area shrinkages were noted in a study that exposed female mice to acrylamide (Khan et al. 1999). Acrylamide doesn’t only have reproductive effects but it also influences reproductive organs that produce hormones and immunohistochemistry. Low body weight, organ weight and development, progesterone concentration in serum reducing effects had been noted in the study conducted on acrylamide-treated female mice (Wei et al. 2014). Figure 1. Metabolism of acrylamide. (Virk-Baker et al. 2014) Running feed. Distribution/Excretion (Treatment Technique (TT) is set instead of MCL for acrylamide because EPA was unable to find any reliable methods which were economically and technically feasible to measure acrylamide at low concentrations. TT is an enforceable procedure which is set by EPA under the Phase II rule. Phase II rule, under the Safe Drinking Water Act requires EPA to review the national primary drinking water regulation periodically. This rule limits the amount of acrylamide use to 0.05% by weight and dosage for the water treatment facilities and requires Every six people in out of ten thousand are expected to develop cancer as a result of ingesting acrylamide containing products. (E. Dybinga et al. 2005) Figure 2. Acrylamide exposure routes and average daily exposure dose. (E. Dybinga et al. 2005) Figure 3. Distribution and toxicokinetics of acrylamide in a mammal. Concepts of PBTK compartment model developed by Kirman et. al. had been applied in creation of Figure 3, which represents distribution of acrylamide in a body with the emphasis to ingestion route of administration. Glycidamide undergoes conjugation reaction with glutathione and produces mercapturic acid. Mercapturic acid produces two metabolites: 1.N-Acetyl-S-(2-hydroxy-2- carbamoylethyl) cysteine. 2.Cysteine and N-Acetyl-S-(1- carbamoyl-2-hydroxyethyl) Cysteine. Glycemide molecules that have not been metabolized stay free and unchanged. Glycidamide is considered to be genotoxic. Glycidamide can be metabolized by epoxide hydrolase, creating glyceramide. Acrylamide metabolism inside a mammalian body takes a few routes: Acrylamide undergoes conjugation reaction with glutathione, and produces mercapturic acid as a product. Acrylamide also undergoes epoxidation reaction with Cyp4502E1, and produces glycidamide. Glycidamide molecule has three possible routes. (E. Dybinga et. Al 2005). Acrylamide is widely used as a building block of PAMs (polyacrylamides) and acrylamide copolymers. Acrylamide copolymers and PAMs are used in many industrial processes such as; wastewaters treatment, paper mills, plastics, dyes, ore processing, and irrigation of water to improve soil texture (L. Brown et al. 1982),(EU 2000). PAMs are also used in consumer products such as; caulking, food packaging and processing, manufacturing of adhesives, pesticide formulations and cosmetic additives (D. Wood et al. 2004). Polyacrylamide is largely used as a flocculator in water treatment facilities, ore processing processes and paper mill industries. PAMs are also widely used in genetic engineering and molecular biology laboratories as a matrix which is utilized to separate nucleic acid components during analysis of DNA sequence (Taeymans et al. 2010). Acrylamide is most commonly formed in carbohydrate rich foods which are heated during preparation to or above 120˚C (C. Gertz et al. 2002), (P. Rydberg et al. 2003). Acrylamide is formed as a by-product of Mailllard browning reaction, the reaction is described in Figure 6 (R. Stadler et al. 2002),(Food Agriculture Organization of the United Nations 2008), (D. Mottram et al. 2002), (F. Perdreschi et al. 2013). Formation of acrylamide begins with reaction of carbonyl compound and amino acid asparagine which results in N-glycosyl conjugation and formation of decarboxylated Schiff base. After decarboxylation, the Schiff base might decompose into acrylamide and an imine or the reaction might be followed by hydrolysis to aminopropionamide and carbonyl compounds (R. Stadler et al. 2002),(Food Agriculture Organization of the United Nations 2008), (D. Mottram et al. 2002), (F. Perdreschi et al. 2013). Cooking methods such as; frying, baking, broiling and roasting are likely to produce acrylamide whereas; boiling and steaming of the foods are less likely to produce acrylamide. Cooking at high temperatures catalyse a chemical reaction between reducing sugars and amino acids in the food which results in the formation of acrylamide. Acrylamide is most commonly found in; Potato Chips, French Fries, Roasted Coffee, Cereal Products, Breads and Bakery Products, Dried Foods, Chocolate Products (K. Skog et al. 2008), (E. Tareke et al. 2002) According to U.S. FDA, there are no guidelines which govern the presence of acrylamide in food but residual amount of acrylamide is regulated in number of food materials (A. Kita et al. 2004), (H. Mojska et al. 2007). Figure 5. Water treatment facility/settling basins. (S. Touze et al 2014) Doerge DR, Young JF, Chen JJ, DiNovi MJ, Henry SH. 2008. Using dietary exposure and physiologically based pharmacokinetic/pharmacodynamic modeling in human risk extrapolations for acrylamide toxicity. Per Rydberg, Sune Eriksson, Eden Tareke, Patrik Karlsson, Lars Ehrenberg a, Margareta Törnqvist*. 2003. Investigations of factors that influence the acrylamide content of heated foodstuffs Kita A, Brathen E, Knutsen SH, Wicklund T. 2004. Effective ways of decreasing acrylamide content in potato crisps during processing. J Agric Food Chem 52:7011-7016. Sumner SC, MacNeela JP, Fennell TR. 1992. Characterization and quantitation of urinary metabolites of [1,2,3-13c]acrylamide in rats and mice using 13c nuclear magnetic resonance spectroscopy. Chem Res Toxicol 5:81-89. Mestdagh F, Castelein P, Van Peteghem C, De Meulenaer B. 2008. Importance of oil degradation components in the formation of acrylamide in fried foodstuffs. J Agric Food Chem 56:6141-6144. Kirman CR, Gargas ML, Deskin R, Tonner-Navarro L, Andersen ME. 2003. A physiologically based pharmacokinetic model for acrylamide and its metabolite, glycidamide, in the rat. J Toxicol Environ Health A 66:253-274. Ghanayem BI, Bai R, Kissling GE, Travlos G, Hoffler U. 2010. Diet-induced obesity in male mice is associated with reduced fertility and potentiation of acrylamide-induced reproductive toxicity. Biol Reprod 82:96-104. Larguinho M, Costa PM, Sousa G, Costa MH, Diniz MS, Baptista PV. 2014. Histopathological findings on carassius auratus hepatopancreas upon exposure to acrylamide: Correlation with genotoxicity and metabolic alterations. J Appl Toxicol 34:1293-1302. Urban M, Kavvadias D, Riedel K, Scherer G, Tricker AR. 2008. Urinary mercapturic acids and a hemoglobin adduct for the dosimetry of acrylamide exposure in smokers and nonsmokers. Registry ATSRD. 2012. Toxicological profile for acrylamide.U.S. Department of health and human services. Wei Q, Li J, Li X, Zhang L, Shi F. 2014. Reproductive toxicity in acrylamide-treated female mice. Reprod Toxicol 46:121-128. Khan MA, Davis CA, Foley GL, Friedman MA, Hansen LG. 1999. Changes in thyroid gland morphology after acute acrylamide exposure. Toxicol Sci 47:151-157. Liu ZH, Cao YM, Zhou QW, Guo K, Ge F, Hou JY, et al. 2013. Acrylamide biodegradation ability and plant growth-promoting properties of variovorax boronicumulans cgmcc 4969. Biodegradation 24:855-864. Rahim MB, Syed MA, Shukor MY. 2012. Isolation and characterization of an acrylamide-degrading yeast rhodotorula sp. Strain mbh23 kctc 11960bp. J Basic Microbiol 52:573-581. Larguinho M, Cordeiro A, Diniz MS, Costa PM, Baptista PV. 2014. Metabolic and histopathological alterations in the marine bivalve mytilus galloprovincialis induced by chronic exposure to acrylamide. Environ Res 135:55-62. IARC. 1985-1986. Acrylamide.Monographs IARC, 1-45. + (Anon 1985-1991 Chemical profile: acrylamide. Chem. Mark Rep., 227, 64 233, 46 239, 42)  PAMs (polyacrylamide) are expected to be highly mobile and biodegradable in soil and water. Residual monomer of acrylamide releases to the soil and lands during industrial production of dyes, plastics and grouting agents which might be in wells. Use of PAMs results in small amounts of the PAMs that escapes into the environment, but is unlikely that it will degrade to acrylamide. Residuals of acrylamide monomer mostly end up in the liquid-water effluent.  Commercially used PAM flocculants in treatment plants contain residual acrylamide monomer, when this residual monomer is released into the environment. Majority of acrylamide that releases from industrial processes as a discharge, ends up in the water. Acrylamide is known to have high water solubility as a result it leaches into the groundwater from the soils that are contaminated with toxic releases (S. Touze et al. 2014),(S. Lande et al. 1979).  Most of acrylamide monomer when used in industrial processes like water treatment facilities ends up in the soil. After the treatment of raw water with the flocculant when the left over water from the treatment process stays in the sludges/soil around the treatment facilities. Many studies have shown that AMD (monomer of acrylamide) leaches into the soil and eventually can reach groundwater if proper care is not taken.  Studies conducted by Lande et al, 1979 found that PAMs are mostly mobile in loamy fine sand and least mobile in slit clay.  When PAMs are in water it can undergo either abiotic or biotic degradation. Number of studies showed that PAM will undergo biodegradation after an initial period of acclimation (S. Touze et al. 2014),(S. Lande et al. 1979). Acrylamide/polyacrylamide can be found two matrices: water and soil. During the treatment process, the treated water seeps into the soil surrounding the facility as a result. Residual of acrylamide can be found in soil. PAMs and acrylamide undergo microbial degradation in the sediment and soils around the water treatment quarries and settling basins. Example of such can be viewed in Fig 5,(Anne Togola 2014).  EU, 2000 risk assessment reports have indicated that photodegradation of acrylamide in surface waters has a half life of about 1 year.  Studies conducted by Lande et al, 1979 demonstrated that highest degradation of acrylamide occurs in soil when the soils have an alkaline pH and high temperatures. Table 2. Environmental levels (S. Touze et al 2014 ), (ATSRD 2012). Sediment around quarries Sediment in environment Water around quarries Water in environment <0.02 to <0.08 µg/g<10 µg/L0.41 to 5.66 µg/L< 5 µg/L It is important to acknowledge that in contrast to all the studies that have discovered and determined acrylamide toxic potentials, knowledge is still limited with regards to effects of acrylamide on a human population. One of the aspects that research can expand on is producing more risk assessment reports based human population, with regards to routes of exposure to acrylamide and comparison of effects on different age groups. Acrylamide is currently classified a possible human carcinogen, however the metabolite glycidamide is considered to have greater affinity towards mutagenesis. More research is needed to analyze glycidamide and the overall possible potentiation of cancer and hormone disrupting effects by acrylamide in combination with other mutagens. treatment facilities submit in writing that levels specified in phase II rule are not exceeded. Currently acrylamide is being reviewed by the EPA during the Second Six Year Review of National Primary Drinking Water Regulations. New technology has been developed by the Swedish National Food Administration in 2002, to treat acrylamide called direct testing procedure. EPA has reviewed the procedure developed by Sweden but EPA is still determining if the cost associated with this procedure is technically reasonable (EPA 2009),(Brown L et al. 1980),(EPA 2014). EPA has determined that, “exposure to acrylamide in drinking water at concentrations of 1.5 mg/L for one day or 0.3 mg/L for 10 days is not expected to cause any adverse effects in a child.” Whereas, polyacrylamide concentrations near water treatment facilities must be less than 0.08 µg/g. (Anne Togola 2014). Treatment technique is discussed in detail in remediation/recommendations section. Figure 6. Acrylamide formation in food. (Mestdagh et al. 2008) Acrylamide is a monomer that is used to generate polyacrylamides (PAMs) via a polymerization reaction. Application of PAMs as a flocculant is widespread in the industry of waste water treatment, which resulted in making waste water treatment the largest contribution of acrylamide into the environment and drinking water contamination. Acrylamide is hydrophilic and water soluble molecule with properties that allow it to leach into the aquatic systems and drinking waters. Acrylamide is currently classified as a Group B2, probable human carcinogen by the United States Environmental Protection Agency (EPA) and International Agency for Research on Cancer (IARC), but is also known to have adverse effects on nervous system for both humans and animals. Awareness and knowledge of everyday exposures to acrylamide through: drinking water, foods, cosmetics and smoking is a cornerstone in future remediation, policy re-evaluations, and lowering pollution strategies.  PAMs degrade into monomers when effected by sunlight, however microbial remediation is more efficient at breaking down PAMs without leaving monomer residual. Acrylamide is hydrophilic and is hard to eliminate out of water by filtration.  Degradation of PAMs had been studied in: aeration, light, pH, and sterilization. In a mineral salt medium a species of Variovorax boronicumulans CGMCC 4969 strain proved to degrade acrylamide, hydrolyzing it to acrylic acid with a half-life of 2.5 minutes. Escherichia coli strain Rosetta (DE3) pLysS also produced notable results by hydrolyzing acrylamide into acrylic acid. Not only was acrylamide degraded, but the metabolic byproducts produced during degradation promoted cell growth (Liu et al. 2013).  Example: Table 5. Concentrations of acrylamide around quarries is smaller than in the environment. Rhodotorula sp. Strain mbh23 kctc 11960bp was able to degrade a full dose of acrylamide in 5 days (Rahim et al. 2012).  Acrylamide is degraded into CO2 and ammonium ions in water and soils. The bacterium found to metabolize acrylamide in aerobic conditions were Bacillus, Pseudomonas, Rhodococcus (Junqua et al. 2014). Some Recommendations for consumption of food and impact on environment are listed below:  Avoid consumption of fried foods, use alternative methods for cooking such as boiling and steaming.  Better techniques must be utilized at the industries which use acrylamide to reduce the impact on the environment. EPACAL/EPAEuropean unionJapan MCGL=0 MCL=TT 0.10 µg/L. 0.0005 µg/L. Table 3. Regulations of acrylamide. 6. Solids Removal: Solids that settle out of the water are removed to drying lagoons or sludge presses for dewatering. 1. Pre-Disinfection: Commonly used in newer plants. Mostly ozone is used to remove TOC (Total Organic Carbon) from raw water. 2. Coagulation: The process of chemical addition to combine suspended solids and colloidal solids creating larger particles that can settle out and/or be filtered out. Chemicals commonly used for this process include aluminum sulfate (alum), ferric chloride, and synthetic polymers. After the addition a process called “flash mixing” occurs, in length of time of 30 to 60 seconds. Flash mixing process disperses the chemicals to mix with TSS (Total Suspended Solids). 3. Flocculation: Gentle mixing process to form larger and heavier particles. 4. Sedimentation (Also Known as Clarification): The particles that are formed through coagulation and flocculation become increasingly larger and eventually settle out of the water in large sedimentation basins. 5. Filtration: After sedimentation, the clarified water is passed through filters to remove particles of dirt, algae, and harmful bacteria and parasites. Filters can are usually made from sand, gravel or granular activated carbon. 7. Post- Disinfection: Chlorine and chlorine containing compounds are typically used for disinfection purposes to disable bacteria, viruses and parasites. (water.epa.gov) Fig 5. represents a diagram of a typical wastewater treatment facility where polyacrylamides are used to treat waste water. There are a few points in a system where polyacrylamides can be injected, depending on the set up of facility. The system presented in the study by Touze et al, injects polyacrylamides at the flocculant injection unit, marked in the diagram as P3. Carassius auratus (gold fish) manifested histopathological alternations in hepatopancreas from exposure to acrylamide. Fish were exposed to acrylamide via their water containers that mimic acrylamide contaminated aquatic conditions. Lethal Concentration at 50% (LD50) occurred with the concentration of 119.5 mg/L, while a 100% mortality of fish occurred at 200 mg/L. The exposed fish manifested DNA breakage, pancreatic cell necrosis Table 1. Use of Acrylamide by industry in percentages directly from the monograph: acrylamide. (IARC 1985-1986) Pie chart displaying usages of acrylamide from year 1991 in Table 1. PAMs are used predominantly in water treatment plants as a flocculant but has other uses in plastics, paper, cosmetics, mineral processing. Acrylamide leaches into aquatic and drinking water via degradation of PAMs that are used in various industries. Acrylamide is also generated during preparation of food with large starch content and high temperature cooking. Surprisingly, concentrations of acrylamide around quarries is smaller than in environment. State of California department of Environmental Protection Agency (Cal/EPA) right to know act, Proposition 65 regulates that a warning be posted to inform the public potentially hazardous substances, but in relation to water EPA had set MCGL to 0, and MCL=TT (Treatment technique). There had been risk assessment studies done, and estimated that risk of developing cancer is 6 out of 10,000 with the current exposures of 0.43 micrograms per a kilogram of body weight. Acrylamide undergoes phase 1 and phase 2 metabolism in mammalian subjects. Exposure routes consist mostly of ingestion, transdermal and inhalation, however the drinking water would fall under oral administration. Acrylamide distribution in the body depends on its route of entry, but it is metabolized by hepatocytes in the liver and is excreted in original and various metabolite forms mostly via urine. Health effects include: nervous system, neurotoxic, carcinogenicity, reproductive and endocrine system disrupting effects. Acrylamide does not only impact mammals but also aquatic populations, studies show necrotic effects on tissues and DNA damage to fish and mussels that were exposed to acrylamide. There are various remediation strategies in the soil that involve microbial organism degradation of acrylamide, which had proved to be very efficient. There is also water treatment strategies involving carbon treatments, filtration, coagulation and chlorine additions. Treatment Technique Process


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