Melamine
Molecular three-dimensional model
Contents
1. Definition
2. Physical and chemical properties
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3. Toxic hazards, diagnosis and treatment
4. Human body tolerance standard for melamine
5. Principle of false protein
6. Melamine added to milk The role of The number of casualties caused by the incident is twelve. A rapid method that can detect melamine in 15 minutes
Edit this paragraph 1. Definition
Melamine (qíng) amine (àn) (English name Melamine ), is a triazine nitrogen-containing heterocyclic organic compound and an important nitrogen-containing heterocyclic organic chemical raw material. Triamine for short, also known as 2,4,6-triamino-1,3,5-triazine, 1,3,5-triazine-2,4,6-triamine, 2,4,6-triamino Urea, melamine, melamine, cyanuric triamide.
More English names: 1,3,5-Triazine-2,4,6-triamine; 2,4,6-Triamino-1,3,5-triazine; 2,4,6- Triamino-s-triazine; Aero; Cyanuramide; Cyanuric triamide; Cyanurotriamide; Cyanurotriamine; DG 002 (amine); Hicophor PR; Isomelamine; Melamine; NCI-C50715; Pluragard; Pluragard C 133; s-Triazine, 2,4,6- triamino-; Teoharn; Theoharn; Virset 656-4;
Molecular structure
Molecular formula C3N6H6
Molecular weight 126.12
CAS registration number 108 -78-1
EINECS registration number 203-615-4
Edit this paragraph 2. Physical and chemical properties
Melamine is a pure white monoclinic prism crystal , odorless, density 1.573g/cm3 (16℃). Melting point under normal pressure is 354℃ (decomposition); rapid heating and sublimation, sublimation temperature is 300℃. Soluble in hot water, water solubility 3 G/L (20 ?C), slightly soluble in cold water, very slightly soluble in hot ethanol, insoluble in ether, benzene and carbon tetrachloride, soluble in methanol, formaldehyde, acetic acid, heat Ethylene glycol, glycerin, pyridine, etc. Low toxicity. It is relatively stable under normal circumstances, but it may decompose and release cyanide at high temperatures. When decomposing, it also releases nitrogen that does not support combustion, so it can be used as a flame retardant.
Melamine molecular model
It is weakly alkaline (pKb=8) and can form melamine salts with hydrochloric acid, sulfuric acid, nitric acid, acetic acid, oxalic acid, etc. In neutral or slightly alkaline conditions, it condenses with formaldehyde to form various hydroxymethyl melamines, but in slightly acidic conditions (pH value 5.5 to 6.5), it undergoes a polycondensation reaction with methylol derivatives to form resin products. When hydrolyzed by strong acid or strong alkali aqueous solution, the amine group is gradually replaced by the hydroxyl group, first forming ammeline, then further hydrolyzing to form ammelide, and finally forming cyanuric acid.
Structural formula
Main uses Melamine is a basic organic chemical intermediate product with a wide range of uses. The most important use is as a raw material for the production of melamine formaldehyde resin (MF). Melamine can also be used as a flame retardant, water reducing agent, formaldehyde cleaner, etc. This resin has higher hardness than urea-formaldehyde resin, is non-flammable, is water-resistant, heat-resistant, aging-resistant, arc-resistant, chemical-resistant, has good insulation properties, glossiness and mechanical strength, and is widely used in wood, plastics, coatings, papermaking, and textiles. , leather, electrical, pharmaceutical and other industries. Its main uses are as follows:
(1) Decorative panels: they can be made into fireproof, earthquake-resistant, heat-resistant laminates, bright-colored, strong and heat-resistant decorative panels for aircraft, ships and furniture. veneer panels and fireproof, earthquake-resistant and heat-resistant house decoration materials.
(2) Coating: After etherification with butanol and methanol, it can be used as a bonding agent for advanced thermosetting coatings and solid powder coatings, and can be used to produce metal coatings and high-grade amino resin decorative paints for vehicles and electrical appliances.
(3) Molding powder: Melamine plastic can be made into melamine plastic through mixing, granulation and other processes. It is non-toxic, anti-fouling, can still maintain good electrical properties when wet, and can be made into white, High-grade insulation materials for daily utensils, sanitary ware, melamine tableware, and electrical equipment that are resistant to beating.
(4) Paper: After etherification, it can be used as a paper treatment agent to produce high-grade paper such as anti-wrinkle, anti-shrink, and non-corruptible banknotes and military maps.
(5) Mixing melamine formaldehyde resin with other raw materials can also produce fabric finishing agents, leather tanning agents, polishing agents and water-resistant agents, rubber adhesives, combustion accelerants, high-efficiency Cement water reducing agent, steel desalination agent, etc.
Edit this paragraph 3. Toxicity hazards, diagnosis and treatment
Currently, melamine is considered to be slightly toxic, and the oral LD50 of rats is greater than 3 g/kg body weight. According to an experimental report in 1945, no obvious poisoning was observed after feeding large doses of melamine to rats, rabbits and dogs. Long-term ingestion of melamine in animals can cause damage to the reproductive and urinary systems, bladder and kidney stones, and can further induce bladder cancer. The third volume of the "International Chemical Safety Manual" and the International Chemical Safety Card jointly compiled by the International Program on Chemical Safety and the European Commission in 1994 only state that long-term or repeated intake of large amounts of melamine may have effects on the kidneys and bladder. Lead to the formation of stones. However, the preliminary investigation results of the 2007 pet food contamination incident in the United States concluded that wheat protein powder adulterated with ≤6.6% melamine was the cause of pet food poisoning, which cast doubt on the conclusion that the above-mentioned toxicity was mild. However, for safety reasons, tableware generally made of melamine will be marked "not for use in microwave ovens."
On September 12, 2008, the Ministry of Health issued the "Diagnosis and Treatment Plan for Urinary System Stones in Infants and Young Children Related to Consumption of Contaminated Sanlu Brand Infant Formula Milk Powder". Relevant parties can refer to it.
The plan points out that most stones involve the bilateral collecting system and bilateral ureters, which is different from the clinical manifestations of adult urinary system stones. Multiple stones have a higher probability of affecting renal function. Since many children do not have the ability to complain of symptoms, parents need to strengthen observation of the children involved. Relying on abdominal B-ultrasound and/or CT examination can help determine the diagnosis early. In terms of treatment, there is currently no specific antidote for the toxic effects of melamine. Clinical practice mainly relies on symptomatic and supportive treatment. If necessary, surgical intervention can be considered to relieve the risk of long-term renal damage in children. Early diagnosis and early treatment are the keys to a speedy recovery for children.
Edit this paragraph 4. Human body tolerance standard for melamine
Melamine is a low-toxic chemical raw material. Animal experiment results show that it is metabolized quickly in the animal body and does not persist, mainly affecting the urinary system.
There is an obvious dose-effect relationship between the dosage of melamine and clinical diseases. The maximum tolerated level of melamine in infants is 15 mg per kilogram of milk powder. A risk assessment conducted by experts on contaminated infant formula shows that, taking a 7-kg infant as an example, assuming a daily intake of 150 grams of milk powder, the safety predetermined value, that is, the maximum tolerated dose, is 15 mg/kg of milk powder.
According to the standards of the US Food and Drug Administration, the tolerable daily intake of melamine is 0.63 mg/kg of body weight per day.
Edit this paragraph 5. Principle of fake protein
Due to the shortcomings of protein content testing methods in the food and feed industry, melamine is often used as a food additive by unscrupulous businessmen to improve food testing. It is an indicator of protein content, so melamine is also called "protein protein".
Protein is mainly composed of amino acids. The average nitrogen content of protein is about 16%, while the nitrogen content of melamine is about 66%. The common protein testing method "Kjeldahl method" estimates the protein content by measuring the nitrogen content. Therefore, adding melamine will make the protein test content of food higher, thereby making inferior food pass the test of the food inspection agency. Some people estimate that the cost of using melamine to increase the tested protein content by one percentage point in plant protein powders and feeds is only 1/5 of that of real protein raw materials. As a white crystalline powder, melamine has little odor and taste, so it is not easy to detect after adulteration.
Milk powder incident: The protein content of various brands of milk powder is 15-20% (I saw some products marked 10-20% on the packaging in the supermarket at night), and the average nitrogen content of the protein is 16%. Calculated based on the protein content of a certain qualified milk being 2.8%, the nitrogen content is 0.44%, and the protein content of a certain qualified milk powder being 18%, the nitrogen content is 2.88%. The nitrogen content of melamine is 66.6%, which is 151 times that of milk and 23 times that of milk powder. Adding 0.1 gram of melamine per 100g of milk can theoretically increase protein by 0.625%.
Slightly soluble means that 1g (ml) of the solute can be dissolved in 100 to less than 1000ml of solvent. Melamine is slightly soluble in water. No experimental data has been found on its solubility in oil-in-water emulsions such as milk. It should be The solubility is better than that of water, yet to be verified.
Testing plan: Among the existing national standards for milk powder testing, protein, fat, bacteria, etc. are mainly tested. Melamine is a chemical raw material and is not allowed to be added to food, so the existing standards will not include corresponding content. That is to say, there is currently no national standard for melamine testing. Therefore, TV Rheinland Group refers to the HPLC-UV quantitative method of the U.S. Food Chemical Codex (FCC), and can also use HPLC/MS detection methods (laboratory methods) for baby food, pet food, feed and their raw materials (including Starch, rice protein, corn protein, gluten, grain and oil, etc.), the test results are authoritative.
Another explanation for the fake protein in Sanlu milk powder is that the company adds urea, and the raw milk is directly turned into milk powder at high temperatures. The high temperature causes the urea to dehydrate and generate melamine. Therefore, The final milk powder also contains melamine.
Edit this paragraph 6. The effect of adding melamine to milk
Milk powder is toxic because it contains melamine, which may be added directly to the milk powder or added to the raw milk. .
Melamine is added to milk and milk powder, mainly because it can impersonate protein.
Foods must be tested for protein content in accordance with regulations. If there is not enough protein, it means that the milk has been mixed with too much water, or that there is too much powder from other things in the milk powder.
However, protein is too difficult to detect, so biochemists came up with a lazy way: because protein contains nitrogen, so as long as the nitrogen content in food is measured, the nitrogen content can be calculated. protein content.
Therefore, it is difficult to detect that the protein of milk powder added with melamine is unqualified. This is the false protein of melamine.
Edit this paragraph 7. Synthesis process
Melamine was first synthesized by
Melamine
Liebig in 1834. The early synthesis used dicyanide. Amine method: Calcium cyanamide (CaCN2) is prepared from calcium carbide (CaC2). Calcium cyanamide is hydrolyzed and dimerized to form dicyandiamide, which is then heated and decomposed to produce melamine. At present, the dicyandiamide method has been eliminated due to the high cost of calcium carbide. Compared with this method, the urea method is low in cost and is currently used more often. Urea uses ammonia as the carrier and silica gel as the catalyst. It boils and reacts at a temperature of 380-400°C. It first decomposes to generate cyanic acid, and further condenses to generate melamine.
6 CO (NH2)2 → C3N6H6 + 6 NH3 + 3 CO2
The generated melamine gas is cooled and captured to obtain a crude product, which is then dissolved to remove impurities and recombined. Crystallize to get the finished product. The production of melamine by urea method consumes about 3800kg of urea and 500kg of liquid ammonia per ton of product.
According to different reaction conditions, the melamine synthesis process can be divided into high-pressure method (7-10MPa, 370-450℃, liquid phase) and low-pressure method (0.5-1MPa, 380-440℃, liquid phase) and atmospheric pressure method (<0.3MPa, 390℃, gas phase).
Most foreign melamine production processes are named after technology development companies, such as BASF Process in Germany, Chemical Linz Process in Austria, Lurgi Process, and Allied Signal Chemical Company in the United States. Chemical method (Allied Signal Chemical), Japan's new Nissan Process (Nissan Process), the Netherlands' Stamicarbon method (DSM method), etc. These production processes can be basically divided into three processes: high pressure method, low pressure method and normal pressure method according to different synthesis pressures. Currently, the most technologically advanced and competitive ones in the world include Japan's Nissan method and Italy's Allied-Eurotechnica's high-pressure method, the Netherlands' DSM low-pressure method and Germany's BASF's atmospheric pressure method.
Chinese melamine production enterprises mostly use the semi-dry atmospheric pressure process. This method uses urea as the raw material below 0.1MPa at about 390°C, uses silica gel as the catalyst to synthesize melamine, and makes the melamine sublimate. Crystallize in the vessel, and the crude product is made into finished product after dissolution, filtration, and crystallization.
Edit this paragraph 8. Related disease cases
In 2007, a pet food contamination incident broke out in the United States. Subsequent investigations showed that wheat protein powder adulterated with ≤6.6% melamine was the cause of pet food poisoning.
In September 2008, an incident involving contamination of Sanlu infant milk powder broke out in China, causing infants and young children who consumed the contaminated milk powder to develop kidney stones. The reason was that the milk powder contained melamine.
Report on the 26th: Shanghai Guangming Food Group decided on the 26th that the White Rabbit toffee produced by Guanshengyuan Company, a subsidiary of Guangming Food Group, and the "Dabai" exported by certain countries and regions from Shanghai Guanshengyuan Food Co., Ltd. Melamine was detected in "Rabbit" milk candies, and some overseas milk candies where melamine was detected are being taken off the shelves and recalled.
The General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China has recently launched an emergency nationwide inspection of melamine content in infant milk powder. This special inspection investigated the remaining 109 companies and inspected 491 batches of products from these companies. Phased inspection results showed that 69 batches of products from 22 infant milk powder manufacturers were detected with varying amounts of melamine.
List of companies detecting melamine in infant formula milk powder
Serial number Nominal company product name Number of samples unqualified Maximum melamine content mg/kg
1 , Shijiazhuang Sanlu Group Co., Ltd. Sanlu brand infant formula milk powder 11 11 2563.00
2 , Shanghai Panda Dairy Co., Ltd. Panda Kebao brand infant formula milk powder 5 3 619.00
< p>3. Qingdao Shengyuan Dairy Co., Ltd. Shengyuan Brand Infant Formula Milk Powder 17 8 150.004. Shanxi Gucheng Dairy Group Co., Ltd. Gucheng Brand Infant Formula Milk Powder 13 4 141.60
5. Jiangxi Guangming Hero Dairy Co., Ltd. Hero Brand Infant Formula Milk Powder 2 2 98.60
6. Baoji Huimin Dairy (Group) Co., Ltd. Huimin Brand Infant Formula Milk Powder 1 1 79.17
7. Inner Mongolia Mengniu Dairy (Group) Co., Ltd. Mengniu brand infant formula milk powder 28 4 68.20
8. Sino-Australian joint venture Dogado Dairy (Tianjin) Co., Ltd. can Qi brand infant formula milk powder 1 1 67.94
9, Guangdong Yashili Group Co., Ltd. Yashili brand infant formula milk powder 30 10 53.40
10, Hunan Peiyi Dairy Co., Ltd. Nanshan Beiyi Brand Infant Formula Milk Powder 3 1 32.00
11. Heilongjiang Province Qining Dairy Co., Ltd. Infant Formula Milk Powder 2 Stage Base Powder 1 1 31.74
12. Shanxi Yashili Dairy Co., Ltd. Yashili brand infant formula milk powder 4 2 26.30
13. Shenzhen Jinbishi Dairy Co., Ltd. Jinbishi brand infant formula milk powder 2 2 18.00
14. Shi En (Guangzhou) Infant Nutrition Products Co., Ltd. Shi En brand infant formula milk powder 20 4 17.00
15. Guangzhou Jinding Dairy Factory Jinding brand infant formula milk powder 3 1 16.20
16. Inner Mongolia Yili Industrial Group Co., Ltd. Yili brand children's formula milk powder 35 1 12.00
17. Yantai Aomeiduo Nutritional Products Co., Ltd. Aomeiduo brand infant formula milk powder 6 6 10.70
18. Qingdao Suokang Nutrition Technology Co., Ltd. Aikeding brand infant formula milk powder 3 1 4.80
19. Xi'an Yanliang District Baiyue Dairy Co., Ltd. Yubao Brand infant formula milk powder 3 1 3.73
20. Yantai Leilei Dairy Co., Ltd. Leilei brand infant formula milk powder 3 3 1.20
21. Shanghai Baoanli Dairy Co., Ltd. Baoanli Brand infant formula milk powder 1 1 0.21
22. Fuding Chenguan Dairy Co., Ltd. Congerzhuang brand infant formula milk powder 1 1 0.09
Melamine was detected in liquid milk Batch list
Company serial number Production company Product name Specifications Model Trademark Production date/batch Melamine (mg/kg)
Mengniu 1 Mengniu (Wuhan) Youzhiyou Dairy Co., Ltd. Walnut milk 200ml/bag Youzhiyou 20080910 0.765
Mengniu 2 Inner Mongolia Mengniu Dairy (Group) Co., Ltd. Mengniu high calcium low-fat milk 250ml/box Mengniu 2008.08.07 0.8
Mengniu 3 Inner Mongolia Mengniu Dairy (Group) Co., Ltd. full-fat sterilized pure milk 250ml/box Mengniu 2008.09.01 1.0
Mengniu 4 Inner Mongolia Mengniu Dairy (Group) Co., Ltd. high-calcium low-fat milk 250ml/box Mengniu 2008.08.01 1.5
Mengniu 5 Inner Mongolia Mengniu Dairy (Group) Co., Ltd. Breakfast Milk (Wheat Flavor) 250ml/pack Mengniu 20080814 1.9
Mengniu 6 Inner Mongolia Mengniu Dairy (Group) Co., Ltd. Mengniu breakfast milk 250ml/box Mengniu 2008.07.26/x 2.57<
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Mengniu 7 Inner Mongolia Mengniu Dairy (Group) Co., Ltd. Wonderful Points 250ml/box Mengniu 20080728/W206 3.17
Mengniu 8 Mengniu Dairy (Beijing) Co., Ltd. Xylitol Yogurt 2kg/ Bottle Mengniu 20080806 3.52
Mengniu 9 Inner Mongolia Mengniu Dairy (Group) Co., Ltd. high calcium low-fat milk 243ml (250g)/bag Mengniu 20080908/C206/GAfb 4.2
Mengniu 10 Mengniu Dairy (Ma'anshan) Co., Ltd. Mengniu large fruit yogurt 160g/box Mengniu M20080903 6.8 (A sample)
Mengniu 11 Mengniu Dairy (Ma'anshan) Co., Ltd. Mengniu large fruit yogurt 160g/box Mengniu M20080903 7 (B Sample)
Yili 1 Jinan Yili Dairy Co., Ltd. Yili Mango + Peach Yogurt 125g/box Yili 2008.09.07 0.69
Yili 2 Inner Mongolia Yili Industrial Group Co., Ltd. Yogurt (Papaya + sweet orange) 125g/bottle Yili 20080903 1.02
Yili 3 Inner Mongolia Yili Industrial Group Co., Ltd. pure milk 220ml/bag Yili 2008.09.13 2.2
Yili 4 Inner Mongolia Yili Industrial Group Co., Ltd. Co., Ltd. Skim milk 250ml/box Yili 20080820 2.9
Yili 5 Inner Mongolia Yili Industrial Group Co., Ltd. Pure milk 220ml/bag Yili 20080905MIAC6 5.5
Yili 6 Inner Mongolia Yili Industrial Group Co., Ltd. Pure milk 242ml/bag Yili 20080906/LIA09 8
Yili 7 Inner Mongolia Yili Industrial Group Co., Ltd. high calcium low-fat milk 250ml/box Yili 20080819 8.4
Guangming 1 Beijing Guangming Fitness Dairy Co., Ltd. Guangming Yogurt (original) 180g/bag Guangming 2008.09.12 0.6
Guangming 2 Wuhan Guangming Dairy Co., Ltd. Original yogurt 180g/box Guangming 2008-09-13 3.41
Guangming 3 Beijing Guangming Jianneng Dairy Co., Ltd. Original yogurt 100g/cup Guangming 20080910A 3.5
Guangming 4 Beijing Guangming Jianneng Dairy Co., Ltd. Large fruit strawberry yogurt 450g/box Guangming 20080902BC 4.8
Guangming 5 Guangming Dairy Co., Ltd. Probiotic Yogurt (original) 190g/can Guangming B20080908C 5.65
Guangming 6 Beijing Guangming Jianneng Dairy Co., Ltd. Yogurt (original) 580g /Bottle Guangming B20080909A 8.6
A case of illegal addition of melamine
In 2007, the Shenzhen Inspection and Quarantine Bureau detected melamine in three batches of "Aizu Brand" ornamental fish feed imported from Taiwan, and the melamine content was Higher, respectively 0.35 g/kg, 0.47g/kg, 0.51g/kg. These 3 batches of fish feed*** are 846 kilograms and worth US$1,016.
In 2007, Fujian, Tianjin, Shandong, and Zhuhai Inspection and Quarantine Bureaus detected positive results for melamine in fishmeal imported from Malaysia, Thailand, and Peru (HS codes were all 2301201000), and the imported fishmeal has been returned in accordance with the law.
According to official news from the U.S. Food and Drug Administration (FDA), the U.S. FDA has found melamine in feed produced in the United States for the first time, and relevant companies have begun to voluntarily recall related products. Feed additives containing melamine were sourced from Tembec BTLSR Inc. of Toledo, Ohio, and Uniscope Inc. of Johnstown, Colorado.
Tembec produces AquaBond and Aqua-Tec II adhesives, mainly for export, and also provides raw materials for the production of Xtra-Bond adhesives to Uniscope. The Xtra-Bond adhesives produced by Uniscope are mainly supplied to the US market. The above-mentioned binders are mainly used to produce pellet feed for cattle, sheep, goats, fish and shrimp. Tembec confirmed that melamine was added to the product formula in order to increase the viscosity of the pellet feed. However, melamine is prohibited from being used as an animal or fish/shrimp feed additive in the United States.
In 2007, the Beijing Inspection and Quarantine Bureau detected positive melamine in pet food imported from Australia (HS code: 2309101000), and returned the imported pet food in accordance with the law.
Related toxicity tests
1> Test method: Oral
Ingestion method: 3161 mg/kg
Test subject: Rodent - rat
Toxicity type: acute
Toxic effects: 1.Details of toxic effects not reported other than lethal dose value
2> Test method: Inhalation
Ingestion method: 3248 mg/m3
Test subject: Rodent - rat
Toxicity type: acute
Toxicity effects: 1.Details of toxic effects not reported other than lethal dose value
3> Test method: Intraperitoneal
Ingestion method: 3200 mg/kg
Test subject: Rodent - rat
Toxicity type: acute
Toxic effects: 1.Sense Organs and Special Senses (Eye) - lacrimation
2.Behavioral - tremor
3.Lungs, Thorax, or Respiration - cyanosis
4> Test method: Unreported
Ingestion method: 6 mg/kg
Test subject :Rodent - rat
Toxicity type: acute
Toxic effects: 1.Details of toxic effects not reported other than lethal dose value
5> Test method: Oral
Ingestion method: 3296 mg/kg
Test subject: Rodent - mouse
Toxicity type: acute
Toxic effects: 1.Details of toxic effects not reported other than lethal dose value
6> Test method: Intraperitoneal
Ingestion method: 800 mg/kg
Test subject :Rodent - mouse
Toxicity type:acute
Toxic effects: 1.Sense Organs and Special Senses (Eye) - lacrimation
2.Behavioral - tremor< /p>
3.Lungs, Thorax, or Respiration - cyanosis
7> Test method: Unreported
Ingestion method: 1 mg/kg
Test object: Rodent - mouse
Toxicity type: acute
Toxic effects: 1.Details of toxic effects not reported other than lethal dose value
8> Test method: Administration onto the skin
Ingestion method: >1 mg/kg
Test subject: Rodent - rabbit
Toxicity type: acute
Toxic effects: 1.Details of toxic effects n
ot reported other than lethal dose value
9> Test method: Oral
Ingestion method: 21840 mg/kg/4W-C
Test subject: Rodent - rat
Toxicity type: MultipleDose
Toxic effects: 1.Behavioral - food intake (animal)
2.Kidney, Ureter, Bladder - other changes< /p>
3.Nutritional and Gross Metabolic - weight loss or decreased weight gain
10> Test method: Oral
Ingestion method: 32760 mg/kg/13W- C
Test subject: Rodent - rat
Toxicity type: MultipleDose
Toxicity effects: 1.Kidney, Ureter, Bladder - other changes
< p>2.Related to Chronic Data - death11> Test method: Oral
Ingestion method: 21 mg/kg/14D-C
Test Object: Rodent - rat
Toxicity type: MultipleDose
Toxic effects: 1. Kidney, Ureter, Bladder - inflammation, necrosis, or scarring of bladder
2 .Nutritional and Gross Metabolic - weight loss or decreased weight gain
12> Test method: Inhalation
Ingestion method: 58 ug/m3/17W-I
Test subject: Rodent - rat
Toxicity type: MultipleDose
Toxicity effects: 1. Liver - other changes
2. Blood - changes in serum composition ( e.g. TP, bilirubin, cholesterol)
3.Biochemical - Enzyme inhibition, induction, or change in blood or tissue levels - transaminases
13> Test method: Oral
< p>Ingestion method: 93600 mg/kg/13W-CTest subject: Rodent - mouse
Toxicity type: MultipleDose
Toxic effects: 1. Kidney, Ureter, Bladder - other changes
14> Test method: Oral
Ingestion method: 50400 mg/kg/14D-C
Test subjects: Rodent - mouse
Toxicity type: MultipleDose
Toxicity effects: 1. Kidney, Ureter, Bladder - inflammation, necrosis, or scarring of bladder
15> Test Method: Administration into the eye
Ingestion method: 500
mg/24H
Test object: Rodent - rabbit
Toxicity type: SkinEyeIrrition
Toxicity effect: 1. Mild
16> Test Method:
Ingestion method: 78 ug/well
Test subject: Bacteria - Escherichia coli
Toxicity type: Mutation
Toxicity Function:
17> Test method: Oral
Ingestion method: 1 mg/kg
Test object: Rodent - mouse
Toxicity type: Mutation
Toxicity effect:
18> Test method: Oral
Ingestion method: 195 mg/kg/2Y-C
Test subject: Rodent - rat
Toxicity type: Tumorigenic
Toxic effects: 1.Tumorigenic - Carcinogenic by RTECS criteria
2.Kidney, Ureter , Bladder - tumors
19> Test method: Oral
Ingestion method: 197 mg/kg/2Y-C
Test subject: Rodent - rat< /p>
Toxicity type: Tumorigenic
Toxic effects: 1.Tumorigenic - Carcinogenic by RTECS criteria
2.Kidney, Ureter, Bladder - tumors
20> Test method: Oral
Ingestion method: 162 mg/kg/2Y-C
Test subject: Rodent - rat
Toxicity type: Tumorigenic
Toxicity effects: 1.Tumorigenic - equivocal tumorigenic agent by RTECS criteria
2.Kidney, Ureter, Bladder - tumors
21> Test method: Inhalation< /p>
Ingestion method: 500 ug/m3, male 17 week(s) pre-mating
Test subject: Rodent - rat
Toxicity type: Reproductive
Toxic effects: 1.Reproductive - Paternal Effects - spermatogenesis (incl. genetic material, sperm morphology, motility, and count)
2.Reproductive - Fertility - pre-implantation mortality (e.g. reduction in number of implants per female; total number of implants per corporalutea)
3.Reproductive - Effects on Embryo or Fetus - fetal death
Edit this paragraph 9. How families test dairy products Does it contain melamine
1. Pour the milk powder into a thicker-than-usual amount with hot water, stir thoroughly until no solid lumps appear, then put it in the refrigerator and wait for the milk to cool down.
2. Prepare a black cloth and an empty cup. Put a black cloth over the mouth of the empty cup to serve as a filter.
3.
Pour the cooled milk over a black cloth and strain.
4. If there is white solid filtered out, rinse it with clean water several times to eliminate other soluble matter.
5. If you find white crystals after rinsing, you can put the crystals into clean water. If the crystals sink to the bottom of the water. Then it is most likely melamine, and this milk powder cannot be used.
This method may not be able to detect trace amounts of melamine, but trace amounts of melamine make it much less likely that children will get stones. At least it can... My answer has gone beyond answering the question. There is a limit of 10,000 words. If you need more details, you can contact me.