Avantrx

Avantrx

Avantrx

Eat Less, Feel Full - Lose Weight Sensibly. Special: Buy One, Get One Free

  • Meal Time Portion Control
  • Designed to Alleviate the Feelings of Hunger Associated with Calorie-Restricted Diets
  • Clinical Study Average 4-week Weight Loss: 7.6 lbs
  • Certified Kosher and BSE Free
  • 60 capsule count per bottle
  • Made in the USA to FDA Good Manufacturing Standards.
  • Recommended dosage: 1 or 2 capsules with 8 oz of water per capsule, 1 or 2 hours before meals
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Advantage Avantrx!

The ingredient in Avantrx is an ultra-pure superabsorbent polyacrylic hydrogel with the ability to absorb up to 1000 times its weight in water. In the stomach, the microbeads released from the professional strength 750 mg capsule are about the size of grains of sugar. They are activated with water to gently expand within a few minutes to the size of grains of rice, filling the stomach with a soft, slippery mass, the volume of a large apple. After a few hours, the slippery gel-like substance safely passes through the GI tract, and is eliminated naturally--without any known harmful side effects.
 
                                             
 
The microbeads are made from a hydrogel polymer specifically developed for use as a temporary pre-meal gastric bulking agent. Polyacrylic hydrogels have been generally recognized as safe for many years and have been used in a wide variety of applications approved by the FDA for ingestion.
 
The polymer is totally bio-inert, a water-swelling slippery gel-like version of the acrylic polymers used in intraocular lenses.
 
Always consult your doctor before starting a weight loss or weight management program.
 
Recommended dosage: Professional Strength Avantrx must always be taken with at least 8 oz of water. It works best when taken with a large glass of water, one to three hours before a meal. If you don't achieve a sense of fullness when taking one Avantrx capsule, increase the dosage to two capsules with an additional 8 oz of water. Everyone is different, so Avantrx works slightly differently for each individual.  A potent full-spectrum (vitamin/mineral/antioxidant) multiple is always recommended when on a reduced-calorie diet.  We recommend Biosyntrx Oculair, or Macula Complete.
 
Precautions: Do not take more than 2 Avantrx capsules before any meal or more than six capsules a day. Diabetics, pregnant and nursing mothers, children under 18, morbidly obese people, or those with any form of pre-existing gastrointestinal disease or medical condition should consult with their physician before use.
 
Overdosage: Do not induce vomiting. Call your physician immediately.
 
Avantrx is manufactured in a GMP facility to meet the same standards for purity required for pharmacuetical products.  Avantrx is Certified Kosher and BSE Free.
 
These statements have not been evaluated by the U.S. Food and Drug Administration.
 
This product is not intended to diagnose, treat, cure or prevent any disease.
 
 

Excess Weight and Disease

Most of us know we look and feel better when we move our bodies and our intentions (All Movement Matters) to keep our weight at an appropriate level for our height, body type and age.  Unfortunately, not enough of us make the connection between degenerative disease and excess weight.  Excess weight, particularly belly fat, affects all body systems including eye health.

Over 50 studies (see below) now link obesity, excess weight and metabolic syndrome to degenerative eye disease including: cataract, macula degeneration, glaucoma, and diabetic retinopathy, as well as increased risk for cancer, cardiovascular disease, stroke and Type 2 diabetes, which is now considered an epidemic in the U.S. Therefore, a sensible portion control plan has become a focus of thought-leading eye doctors, as has recommending that patients make lifestyle changes that include: eating natural whole foods, getting regular physical activity through moderate exercise, and taking a potent full-spectrum (vitamin/mineral/antioxidant) multiple, particularly when on a reduced-calorie diet. We recommend Oculair or Macula Complete.
 
In almost all cases, managing weight and keeping it off is a simple math formula:
  • reduce caloric intake
  • improve macro- and micronutrient intake
  • increase amount of calories burned.
References:
 
Obesity and Eye Disease
1. Measures of obesity and age-related eye diseases. Klein BE, Klein R, Lee KE, Jensen SC. Ophthalmic Epidemiol. 2001 Sep;8(4): 251-62 [abstract]
 
2. Obesity and eye diseases. Cheung N, Wong TY. Surv Ophthalmol. 2007 Mar-Apr; 52(2);180-95 [abstract]
 
3. Obesity is a risk factor for eye diseases. Habot-Wilner Z, Belkin M. Harefuah. 2005 Nov;144(11):805-9,821 [abstract]
 
4. Aging and retinal vascular diseases. Takagi H. Nippon Ganka Gakkai Zasshi. 2007 Mar;111(3):207-30 [abstract]
 
5. Systematic review of the long-term effects and economic consequences of treatments for obesity and implications for health improvement. Avenell A, Broom J, Brown TJ, et al. Health Technol Assess. 2004 May;8(21): 1-182 [abstract]
 
6. Dietary approaches that delay age-related diseases. Everitt AV, Hilmer SN, et al. Clin Interv Aging. 2006;1(1):11-31 [abstract]
 
Excess Weight / Macular Degeneration Studies:
1. A study of the relation between body mass index and the incidence of age related macular degeneration. Moeini HA, Masoudpour H, Ghanbari H. Br J Ophthalmol. 2005 Aug;89(B): 964-6 [abstract]
 
2. Progression of age-related macular degeneration; association with body mass index, waist circumference, and waist-hip ratio. Seddon JM, Cote J, David N, Rosner B. Arch Ophthalmol. 2003 Jun;121(6): 785-92 [abstract]
 
3. Body mass index and the incidence of visually significant age-related maculopathy in men. Schaumberg DA, Christen WG, Hankinson SE, Glynn RJ. Arch Ophthalmol. 2001 Sep; 119((): 1259-65. [abstract]
 
4. Cardiovascular risk factors and age-related macular degeneration: the Los Angeles Latino Eye Study. Fraser-Bell S, Wu J, Klein R, Asen SP, Hooper C, Foong AW, Varma R. Am J Ophthalmol. 2008 Feb;145(2): 308-16 [abstract]
 
5. Risk factors for the incidence of Advanced Age-Related Macular Degeneration in the Age-Related Eye Disease Study (AREDS) AREDS report no. 19. Clemons TE, Milton RC, Klein R, Seddon JM, Ferris FL 3rd; Age-Related Eye Disease Study Research Group. Ophthalmology 2005 Apr;112(4):533-9 [abstract]
 
6. Cardiovascular disease, its risk factors and treatment, and age-related macular degeneration: Women's Health Initiative Sight Exam ancillary study. Klein R, Deng Y, Klein BE, Hyman L, Seddon J, Frank RN, Wallace RB, Hendrix SL, Duppermann DB, Langer RD, Kuller L, Brunner R, Johnson KC, Thomas AM, Hanna M. Am J Ophthalmol. 2007 Mar; 143(3):473-83 [abstract]
 
7. A prospective study of 2 major age-related macular degeneration susceptibility alleles and interactions with modifiable risk factors. Schaumberg DA, Hankinson SE, Guo Q, Rimm E, Hunter DJ. Arch Ophthalmol. 2007 Jan; 125(1): 55-62 [abstract]
 
8. Plasma fibrinogen levels, other cardiovascular risk factors, and age-related maculopathy: the Blue Mountain Eye Study. Smith W, Mitchell P, Leeder SR, Wang JJ. Arch Ophthalmol. 1998 May; 116(5): 583-7 [abstract]
 
9. Predictors of optical density of lutein and zeaxanthin in retinas of older women in the Carotenoids in Age-Related Eye Disease Study, an ancillary study of the Women's Health Initiative. Mares JA, LaRowe TL, Snodderly DM, Moeller SM, Gruber MJ, Kelin ML, Wooten FR, Johnson EJ, Chappell RJ; CAREDS Macular Pigment Study Group and Investigators. Am J Clin Nutr. 2006 Nov;84(5): 1107-22 [abstract]
 
10. Early age-related maculopathy and risk factors of cardiovascular disease in middle-aged Lithuanian urban population. Paunksnis A, Clmbalas A, Cerniauskiene LR, Luksiene DI, Margeviciene L, Dammarkiene S, Tamosiunas A, Norkus A. Eur J Ophthalmol. 2005 Mar-Apr; 15(2): 255-62 [abstract]
 
11. Age-related macular degeneration: analysis in two ophthalmological centers in Pernambuco-Brazil. Santos LP, Diniz JR, Leao Ac, Sena MF. Arg Bras Oftalmol. 2005 Mar-Apt;6892):229-33 [abstract]
 
12. Obesity, lutein metabolism, and age-related macular degeneration: a web of connections. Johnson EJ. Nutr Rev. 2005 Jan;63(1): 9-15 [abstract]
 
13. The potential role of oxidative stress in the pathogenesis of the age-related macular degeneration (AMD). Drobek-Slowik M, Karczewicz D, Safranow K. Postepy Hig Med Dose 2007;61:28-37 [abstract]
 
14. Macular Pigment and Percentage of Body Fat. Nolan J, Donovan O, et al. IOVS
2004;45:3940-3950. [abstract]
 
15. Macular Pigment Density is Reduced in Obese Subjects. Hammond B, Ciulla T, Snodderly D. IOVS 2002;43:47-50 [abstract]
 
16. The retinal ciliopathies. Adams NA, Awadein A, Tomas HS. Ophthalmic Genet. 2007 Sep;28(3): 113-25. [abstract]
 
17. Predictors of optical density of lutein and zeaxanthin in retinas of older women in the Carotenoids in Age-Related Eye Disease Study, an ancillary study of the Women's Health Initiative. Mares JA, LaRowe TL, Snodderly DM, et al. Am J Clin Nutr. 2006 Nov;84(5):1107-22 [abstract]
 
18. Phytochemicals and age-related eye diseases. Rhone M, Basu A, Nutr Rev. 2008 Aug;66(8): 465-72 [abstract]
 
19. Modifiable risk factors for age-related macular degeneration. Guymer RH, Chong EW. Med J Aust. 2006 May 1;184(9): 455-8 [abstract]
 
Excess Weight / Cataract Studies:
1. Weight status, abdominal adiposity, diabetes, and early age-related lens opacities. Jacuqes PF, Moeller SM, Hankinson SE, et al. Am J Clin Nutr. 2003 Sep;78(3):400-5 [abstract]
 
2. A longitudinal study of body mass index and lens opacities. The Framingham Studies. Hiller R, Podgor MJ, Sperduto RD, et al. Ophthalmology 1998 Jul;105(7):1244-50 [abstract]
 
3. Anthropometric status and cataract: the Salisbury Eye Evaluation project. Caulfield LE, West SK, Barron Y, Cid-Ruzafa J. Am J Clin Nutr. 1999 Feb;69(2):237-42 [abstract]
 
4. Body mass index and age-related cataract; the Shihpai Eye Study. Kuang TM, Tsai SY, et al. Arch Ophthalmol. 2005 Aug;123(8):1109-14 [abstract]
 
5. Risk factors for nuclear, cortical and posterior subcapsular cataracts in the Chinese population of Singapore: the Tanjong Pagar Survey. Foster PJ, Wong TY, et al. Br J Ophthalmol. 2003 Sep;87(9):1112-20 [abstract]
 
6. Cataract formation and prevention. Schichi H. Expert Opin Investig Drugs. 2004 Jun;12(6):691-701 [abstract]
 
7. Ocular changes, risk markers for eye disorders and effects of cataract surgery in elderly people: a study of an urban Swedish population followed from 70 to 97 years of age. Bergman B, Nilsson-Ehle H, Sjostrand J. Acta Ophthalmol Scand. 2004 Apr;82(2): 166-74 [abstract]
 
8. Relations between cataract and metabolic syndrome and its components. Paunksnis A, Bojarskiene F, et al. Eur J Ophthalmol. 2007 Jul-Aug;17(4):605-14 [abstract]
 
9. Prevalence and risk factors of lens opacities in the elderly in Cuenca, Spain. Navarro Esteban JJ, Burierrez Leiva JA, et al. Eur J Ophthalmol. 2007 Jan-Feb;17(1):29-37 [abstract]
 
10. Association of metabolic syndrome components with cataract. Bojarskiene F, Cerniauskiene LR. Medicina (Kaunas). 2006;42(2):115-22 [abstract]
 
Excess Weight / IOP and Glaucoma Studies
1. Relationship between intraocular pressure and obesity in children. Akinci A, Cetinkaya E, et al. J Glaucoma. 2007 Oct-Nov;16(7):627-30 [abstract]
 
2. Relationship between intraocular pressure and obesity in Japan. Mori K, Ando F, et al. Int J Epidemiol. 2000 Aug;29(4):661-6 [abstract]
 
3. Relationship between intraocular pressure and systemic health parameters in a Korean population. Lee JS. Lee SH, Oum BS, et al. Clin Experiment Ophthalmol. 2002 Aug;30(4):237-41 [abstract]
 
4. Elevated intraocular pressure is associated with insulin resistance and metabolic syndrome.
Oh SW, Lee S, Park C, Kim DJ. Diabetes Metab Res Rev. 2005 Sep-Oct;21(5):434-40 [abstract]
 
5. Association of life-style with intraocular pressure in middle-aged and older Japanese residents. Yoshida M, Ishikawa M, Kokaze A, et al. Jpn J Ophthalmol. 2003 Mar-Apr; 47(2); 191-8 [abstract]
 
6. Associations with intraocular pressure in Latinos: the Los Angeles Latino Eye Study. Memarzadeh F, Ying-Dai M, Azen SP, et al. Am J Ophthalmol. 2008 Jul;146(1):69-76 [abstract]
 
7. The eye and sleep apnea. McNab AA. Sleep Med Rev. 2007 Aug;11(4): 269-76 [abstract]
 
8. Sleep-disordered breathing and effects on ocular health. Dhillon S, Shapiro CM, Flanagan J. Can J. Ophthalmol. 2007 Apr;42(2); 238-43 [abstract]
 
9. Exploring the pathogenesis of IIH: An inflammatory perspective. Sinclair AJ, Ball AK, et al. J Neuroimmunol. 2008 Aug 1. [abstract]
 
10. Profiles of obesity, weight gain, and quality of life in idiopathic intracranial hypertension (pseudotumor cerebri). Daniels AB, Liu BT, Volpe NJ, et al. Am J Ophthalmol. 2007 Apr;143(4):635-41 [abstract]
 
Excess Weight / Type 2 Diabetic Retinopathy Studies
1. Preventing diabetes in the clinical setting. Burnet DL, Elliott LD, Quinn MT, et al. J Gen Intern Med. 2006 Jan;21(1):84-93 [abstract]
 
2. Components of the Metabolic Syndrome and Risk of Cardiovascular Disease and Diabetes in Beaver Dam. Klein B, Klein R, Lee K. Diabetes Care 2002 25:1790-1794. [abstract]
 
3. Association between the Metabolic Syndrome and Retinal Microvascular Signs: The Atherosclerosis Risk in Communitities Study. Wong, T, Duncan B, Golden Sh, Klein, R, et al. IOVS. 2004;45:2949-2945 [abstract]
 
4. Retinal vascular caliber, cardiovascular risk factors, and inflammation: The Multi-Ethnic Study of Atherosclerosis (MESA) IOVS 2006;47:2341-2350 [abstract]
 
5. Ten-Year Incidence of Retinal Vein Occlusion in an Older Population. The Blue Mountain Eye Study. Cugati S, Want J, Rochtchina E, et al. Arch Ophthalmology 2006;124:726-732 [abstract]
 
6. Preventing type 2 diabetes: genes or lifestyle? Weber MB, Narayan KM. Prim Care Diabetes. 2008 Jun;2(2): 65-6 [abstract]
 
7. Ocular and systemic factors associated with diabetes mellitus in the adult population in rural and urban China. The Beijing Eye Study. Xu L, Xie XW, Wang YX, Jonas JB. Eye 2008 Feb 8. [abstract]
 
8. Contributions of inflammatory processes to the development of the early stages of diabetic retinopathy. Kern TS. Exp Diabetes Res. 2007;2007:95103 [abstract]
 
9. Nutrition ad metabolic syndrome. Matia MP, Decumberri Pascual E, Calle Pascual AL. Rev Esp Salud Publica. 2007 Sep-Oct;81(5): 489-505 [abstract]
 
10. Prediabetes: a position statement from the Australian Diabetes Society and Australian Diabetes Educators Association. Twigg SM, Kamp MC, Davis TM, et al. Med J Aust. 2007 May 7;186(9):461-5 [abstract]
 
11. Identification and treatment of prediabetes to prevent progression to type 2 diabetes. Fonseca VA. Clin Cornerstone. 2007;8(2):10-8 [abstract]
 
12. Progress in the prevention of type 2 diabetes. Schernthaner G. Wien Klin Wochenschr. 2003 Nov 28;115(21-22):745-57 [abstract]
 
13. Eye Disease and the Older Diabetic. Tumosa N. Clin Geriatr Med. 2008 Aug;24(3): 515-527 [abstract]
 
14. Anterior ischemic optic neuropathy associated with metabolic syndrome. Kosanovic-Jakovic N, Ivanovic B, et al. Arg Bras Oftalmol. 2008 Jan-Feb;71(1):62-6 [abstract]
 
15. Screening for type 2 diabetes: literature review and economic modelling. Waugh N, Scotland G, et al. Health Technol Assess. 2007 May; 11 (17): 1-125 [abstract]
Professional Strength Avantrx Ingredient Clinical Study and Safety Data
Avantrx Ingredient Study Participant Statistics:
 
1. Average Age: 49
2. Average Beginning: BMI - 30.5; Weight - 183 lbs; Height - 65 inches
3. Average Ending: BMI - 29.3; Weight - 175 lbs; Height - 65 inches
  • Responders: 94.1%
  • Average 4-week weight loss: 7.6 lbs (4.2% body mass)
  • Average number of capsules taken per day: 2
  • Average reduction in meal portion size: 34.3%
  • Average rating of hunger control effectiveness: 86.7%
  • Average time to feel fullness effect: 33 minutes
  • Average duration of fullness effect: 2.5 hours
  • Total doses administered during study period: >2,000
Total incidence of side-effects: 3.6%: Adverse events: None
 
 
In the first graph, participants were asked to rate their responses from the formula's effects at each breakfast, lunch and dinner. The formula generated a sensation of fullness or early satiety 94.1% of the time. In 5.9% of meals, patients described that "No Effect' was noted. 
 
    
 
The second graph represents the number of meals consumed during the 4-week study period by the 30 subjects. 30.8% of the meals were reduced in size by 10-24%. Another 30.8% of meals were reduced in size by 22-49%, and 38.5% of the meals were reduced in size by 50%.
   
     
 
The study participants lost an average of 1.9 lbs per week, with an average weight loss of 7.6 pounds over the 4-week study period.
 
 
No adverse events were reported during the study. Slight burping for a few minutes as the capsule dissolved (within 10 minutes of ingestion) was the most common side effect reported. Occasionally, these burps were accompanied with a mild taste that lasted for a few minutes.
 
Professional Strength Avantrx Ingredient Safety Data

Super Absorbent Polymers (SAP), [like SWELL, the ingredient in Avantrx, which is the subject of this GRAS determination], are used in a variety of consumer, medical and industrial products. SAP products are cross-linked homopolymers of partially neutralized acrylic acid, i.e., hydrogels. Neutralization is accomplished by sodium hydroxide solution. In the dry form SAP is a granular powder of crystalline structure. Commercial SAP is practically dust free because it contains much less than 0.1% of granules below 10 ?m of diameter.

Upon swelling with water, it yields a gel-like suspension. The retention of water is facilitated by the negative carboxylic groups of the polymer and their hydration with water molecules. Due to its cross linking, SAP is essentially insoluble in water. However, should incomplete polymerization occur, small amounts of a water extractable fraction can exist within the polymer matrix.

SAPs have been evaluated in various test systems to elucidate their toxicological profile for both handling during production and use in an article like a diaper, or in their purified forms for ingestible purposes like: pharmacologic agents, excipients, adjuvants, bulking agents, rheologic agents. These toxicity data are substantial to draw conclusions on the potential risk of SAPs to human health through its whole lifetime.

Note: Not all of the different variations of the super absorbent polymers were tested with all the following test systems due to ethical and economical reasons. Some data has been drawn in analogy.

Acute oral toxicity

LD50 > 5,000 mg/kg body weight. Up to 5% (w/v) SAP as a gel in 0.9% (w/v) saline were applied with a stomach tube to 5 male and 5 female rats each. No toxic symptoms were observed and body weight development was normal during observation over 14 days after single application. Necropsy revealed no visible organ alterations.

Application of a watery extract of SAP (in the drinking water) to 6 male and 6 female rats for 1 day led to no symptomatic effects. No fatalities or any visible organ changes were observed.

Subacute oral toxicity

The oral toxicity of SAP, when administered daily to 10 male and 10 female rats per group via the diet over 4 consecutive weeks at concentrations of up to 5% weight of SAP by volume were investigated. No changes of toxicological significance were induced. The differences observed between treated and control animals were limited to increases in water consumption and modification in urinary ion excretion in treated animals. Both findings were considered to be related to the relatively high concentration of sodium in the test substance and therefore of no toxicological significance. (Research Toxicology Centre, Italy)

Elimination after oral application

The elimination of radio-labeled [14C]-SAP in the rat model following single oral administration has been investigated and the rates and routes of excretion and tissue distribution of total radioactivity were determined. By a recovery rate in excess of 96% nearly the entire administered dose was excreted within 5 days and the main route of excretion was via feces. Levels of radioactivity in tissues and organs were low. Biliary elimination of total radioactivity did not occur to any significant extent. Determination of the whole blood kinetics has shown also low levels of radioactivity in blood with peak levels attained between 0.5 - 1 hour post dosing. The results indicate that SAP is very poorly absorbed following oral administration. (Inveresk Research International Ltd., U.K.)

Acute inhalation toxicity on SAP dust

The acute inhalation toxicity of fine dust of SAP was determined in rats in a single 4 hour snout only exposure. The actual exposure concentrations ranged from 0.95 to 5.54 g/m3 with respirable fractions (mass medium aerodynamic diameter (MMAD) < 3.5 ?m) of 25-40% of the total dust. A reduced respiration rate was noted during exposure for all treated groups and mortality at exposure concentrations at or in excess of 3.73 g/m3 was produced. Histological examination of respiratory tissues showed evidence of an inflammatory response, primarily in the lungs consisting mainly of increased macrophages and mild lymphocytic infiltration. Based on the observations recorded during the study and the histological findings 0.98 g/m3 of fine dust is considered to be a sublethal dose level. (Inveresk Research International Ltd., U.K.)

Elimination after intratracheal administration

The elimination of radio-labeled [14C]- SAP in the rat following single intratracheal administration has been investigated. The levels of total radioactivity in the lung decreased throughout the study period of one week, indicating absorption of radio-labeled components. At the end of study approximately 15% of administered radioactivity was left in the lung. Of the tissues examined, highest levels of total radioactivity were found in the liver (5%) and in the kidney (1%) at 1 hour post dose. Urinary excretion of radio-labeled components was 26% after one week after administration. The mechanism of absorption and the components are unknown. (Inveresk Research International Ltd., U.K.)

Subacute inhalation toxicity on SAP dust

20 male and 20 female rats were exposed to particulate SAP of a mass median aerodynamic diameter (MMAD) of < 10 ?1m for 6 hours/day; 5 days/ week, for 4 weeks to nominal exposure levels of 0.1, 1.0 and 10.0 mg/m3; the actual concentrations were 1.7,4.0 and 21.1 mg/m3. No biologically significant findings regarding ophthalmology, growth behavior, wet organ weights, hematology, clinical chemistry and pulmonary function were reported. Histological examination revealed a mild inflammatory reaction with increased numbers of macrophages in the alveoli and minimal lymphocyte response. There was some minimal evidence of a dose dependency but no evidence of significant inflammation, tissue destruction or fibrosis. (Temple University, Philadelphia, U.S.A.)

Note: Chronic inhalation of fine dust may exert inflammatory reactions in the lung. SAP was not tested in a chronic inhalation study. However, a chronic (2-year) lifetime inhalation study with another intentionally micronized super absorbent polymer dust (to get completely respirable particles) performed on rats resulted in a non-specific inflammatory response in the lungs of the rats, followed in the highest chronic exposure level by tumor development in some animals. The no observed effect level (NOEL) was 0.05 mg/m3. Therefore an occupational guidance value (OGV) of 0.05 mg/m3 is recommended.

Acute dermal toxicity

LD50 2,000 mg/kg body weight of up to 5% (w/v) of SAP as a gel in a 0.9% (w/v) saline applied to the shorn skin of 5 male and 5 female rats. No toxic symptoms were observed; body weight development was normal for 14 days after application; necropsy revealed no visible organ alterations; no deaths occurred: SAP is practically non-toxic when applied dermally.

Subacute dermal toxicity

Application of 0.5 g of SAP on shorn and scarified skin of rabbits for five consecutive days under occlusion led to no abnormal findings with respect to any local (i.e. irritation) or systemic effects. Systemic effects were evaluated with hematological and clinical parameters. (International Bio Research-IBR, Germany)

Subchronic dermal toxicity

Repeated application of 0.05 ml of a saline extract of SAP onto the shorn skin, without occlusion, of 10 female mice of the strain, transiently and occasionally very slight edemas accompanied with a slight increase in skinfold thickness. The test substance was applied 3 times/week over 8 weeks. Body weight was within normal range; no systemic effects, due to the test substance, were observed.

A test for skin compatibility as a subchronic dermal assay was performed. 10 female mice were exposed to 0.05 ml of 5% and 7.5% (w/v) suspensions of SAP in 0.9% (w/v) saline, three times a week. Toxicity or any other adverse effects to the skin were not observed. There were no deaths. Body weight development was normal.

Acute skin irritation

Application of 0.5 ml of a saline extract of SAP onto the shorn skin of 3 rabbits (both sexes) under occlusion over a period of 4 hours showed no edema or erythema formation. No other skin lesions were observed, as there were no systemic effects. Test duration was 7 days.

Acute eye irritation

Application of 0.1 g of SAP into the conjunctival sac of the eyes of rabbits caused very slight erythema and mild transient corneal injury. There were no systemic symptoms due to the application of the test substance. The observed very slight irritative effects onto mucous membranes of the eyes and the cornea are caused by the somewhat abrasive properties of the dry, crystalline powder of SAP, and the capacity of SAP to dry out the membranes due to the uptake of fluid during swelling. A watery suspension of SAP exerts no such effects on the eyes of rabbits.

HET-CAM-Test

Chorioallantoic membrane (CAM) assay (HEN'S EGG TEST): 200 mg of dry SAP was applied onto the CAM of hen embryos of 10 days of age. There were no adverse effects with respect to vascular injection, hemorrhaging, or coagulation. Potential for cell toxicity and adverse effects on membranes seems to be very low.

Cytotoxicity in vitro

Cell toxicity: SAP has been examined regarding its influence on mammalian cells in a cell culture system using a fibroblastic cell line derived from mice. The cells were incubated for 24 hours with an extract of SAP (15 g/l of 0.9% sodium chloride solution) in concentrations up to 10% (v/v) in cell culture medium. No adverse effects on the morphology or viability of the cells were observed. Extraction of SAP with cell culture medium (10 g/l of medium) led to a concentration dependent decrease in cell viability due to complex formation (binding) of essential cations in the medium. Following supplementation of the bound cations, adverse effects were not observed any longer. Further cell toxicity tests were executed using the agar diffusion cell culture technique, which is appropriate for solid specimens as well. SAP was applied as dry granulate and as a suspension (30 g/l of 0.9% sodium chloride solution). There was no indication of cytotoxic effects.

Intravenous and intraperitoneal application

Intravenous and intraperitoneal compatibility of SAP was tested after systemic injection in mice. Following intraperitoneal application of 50 ml/kg extract in sesame oil or 10 g/kg extract in polyethylene glycol no toxic reactions of the animals were observed within 72 hours. Intravenous instillation of a SAP extract (15 g/l of 0.9% of sodium chloride solution) produced systemic effects and mortality in dose levels greater than 40 ml/kg. Histopathological examination revealed dose dependent toxic alterations to liver and spleen. The no observed effect level (NOEL) is less than 10 ml/kg, a dose where only minimal hepatic effects have been observed.

Subcutaneous and intramuscular implantation

Subcutaneous and intramuscular compatibility of a gel and the granulate of SAP was tested in rabbits after implantation. Histopathology revealed no abnormal reactions in the surrounding tissue. Furthermore, there were no significant deviations from normal values in hematology, clinical chemistry, and other standard toxicological parameters. No signs of toxicity were observed. (International Bio Research - IBR, Germany)

Hemocompatibility

Hemocompatibility of SAP was tested with the extract and a gel-like suspension of the polymer against human erythrocytes of different blood groups. No hemolysis could be observed under the test conditions employed. Therefore SAP is compatible to blood.

Influence on the vaginal mucosa

SAP was examined with respect to its influence on vaginal mucosa tolerance through single intravaginal administration to rabbits. The dosage levels used were 0.33 and 3.0 g/animal. There were no observed toxic symptoms, nor any deaths. Body weight development was normal, as were the amounts of food and drinking water consumed. The mucosa of the vagina was examined macroscopically and microscopically. No pathological changes were observed relating to SAP. (Laboratory for Pharmacology & Toxicology, Hamburg, Germany)

Allergic contact sensitization (GPMT)

SAP has been tested with respect to its potential to sensitize animals after skin contact according to the maximization test of Magnusson and Kligman. Twenty (20) guinea pigs of either sex were treated intradermally with a water extract [1% (w/v)] and dermally with 1% and 7.5% (w/v) gels in 0.9% (w/v) saline during the induction period. The challenge was executed with 1%,5% and 7.5% (w/v) gels in 0.9% (w/v) saline: No erythemas or edemas were observed; therefore, it is unlikely for SAP to exhibit a potential for skin sensitization.

Human allergic contact sensitization

Human repeat insult patch test (HRIPT): Saline [O.9% (w/v)] extracts of SAP were applied repeatedly as patches on the upper arm of 44 human volunteers, of either sex, aged 18 years or more. Nine induction patches each, to be worn for 24 hours, were used over a period of 3 weeks (3 for each week). One challenge patch was applied for 24 hours with reading and grading 48 and 96 hours after application. The test showed no evidence of skin sensitization for SAP. (CTC International Ltd., U.K.)

Human irritation test

A cumulative irritation test over 21 consecutive days was performed with 0.3 g of a gel of SAP [10% (w/v) in isotonic saline] on volunteers. The gel scored 0.01 points out of 4.0, and was rated "very mildly" irritating. (Harris Laboratories, Inc., Lincoln, Nebraska, U.S.A.)

Teratogenicity

Pregnant female rats were exposed in a teratology study to respirable levels (particle size < 10 ?m) of SAP at 0.3, 1.0 and 10 mg/m3 for 6 hours/day from day 6 to day 15 of gestation. On day 20 of gestation the rats were necropsied and examined by number of implantations, early and late resorptions, live and dead fetuses and number of corpora lutea. The fetuses were observed for weight, external, soft tissue and skeletal alterations. No effects were observed: The no observed effect level (NOEL) is greater than the highest concentration applied. (Texas Tech University, Department of Physiology, U.S.A.)

Salmonella typhimurium reverse mutation assay

Mutagenicity was tested with an extract of SAP [10 g/l of 0.9% (w/v) sodium chloride solution] which contains constituents extractable with water: The test was done with the AMES-Salmonella-plate test (in vitro) with and without metabolic activation by rat liver microsomes for screening for mutagenic properties. The strains TA 100 and TA 1535 were used (base pair substitution) as well as TA 98 and TA 1537 (frameshift mutation). Cytotoxic effects were not observed up to a quantity of 100 ?l of the above mentioned extract per plate. An increase in the revertants was not detected in any of the examined cases. Therefore, there was no indication of a mutagenic potential in S. typhimurium of the extract of SAP. (Laboratory for Pharmacology & Toxicology, Hamburg, Germany)

A further AMES test was executed with an extract of SAP [20 g/l of 0.9% (w/v) saline with 10% (v/v) ethanol] which contains constituents extractable with water and alcohol, with and without metabolic activation by rat liver microsomes. The strains TA 100, TA 1535, TA 98 and TA 1537 were used. An increase in the revertants was not detected in any of the examined cases. Therefore, there were no indications of a mutagenic potential in S. typhimurium of the extract of AP up to the equivalent of 20 mg/plate. (Microtest Research Ltd., U.K.)

Escherichia coli reverse mutation assay

Extracts of SAP were tested in tryptophan requiring strains of Escherichia coli for their ability to induce point mutations with and without the presence of a metabolic activation system. Up to 5,000 ?g/plate no mutagenic events could be observed. Furthermore, cytotoxicity was not detected up to 5,000 ?g/plate. (Hazleton Microtest, U.K.)

In vitro mammalian cell gene mutation test

Mouse lymphoma L-5178-Y cells were exposed with (S 9 mix from Aroclor induced rat liver) and without metabolic activation to an extract of SAP [20 g/l in 0.9% (w/v) saline with 10% (v/v) ethanol]. The test substance failed to induce point mutations at the hypoxanthine guanine phosphoribosyltransferase (HGPRT) locus up to the equivalent of 200 ?g/ml. (Microtest Research Ltd., U.K.)

Mouse lymphoma L-5178-Y cells were exposed with (S 9 mix from Aroclor induced rat liver) and without metabolic activation to an extract of SAP in 0.9% (w/v) saline with 10% (v/v) ethanol. The test substance failed to induce point mutations at the thymidine kinase (TK) locus up to the equivalent of 1.5 mg/ml. No cytotoxicity was observed. (Hazleton America, Inc., U.S.A.)

UDS in rat hepatocytes in vitro

SAP was tested for its ability to induce unscheduled DNA synthesis (UDS) in isolated rat hepatocytes in vitro. Treatment with up to 1,500 ?g/ml of equivalent extracted material [i nO. 9% (w/v) saline with 10% (v/v) ethanol] did not produce a mean net grain count greater than zero (0), nor were 20% or more cells to be found in repair. The test substance therefore failed to produce genotoxic activity. (Hazleton Microtest, U.K.)

In vivo mouse bone marrow micronucleus test

SAP was assayed in an in vivo mouse bone marrow micronucleus test at the highest oral dose level (375 mg/kg) due to its thick consistency. Groups of 5 male and female animals were used and were killed at intervals of 24, 48 and 72 hours after treatment. At no time point was there a significant increase in micronucleus frequency in any group. Therefore, it is concluded that SAP is not able to induce micronuclei in polychromatic or normochromatic erythrocytes of bone marrow of mice. (Microtest Research Ltd., U.K.)

Growth of pathogenic microorganisms

In order to answer the question if pathogenic microorganism can grow on SAP, which may be used in hygiene products, pharmaceutical applications, food additives or in food packaging, the growth behavior of pathogenic microorganisms and the potential production of toxins where investigated:

Growth behavior of the pathogenic microorganisms Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans alone or in combination was determined with a saline (0.9%) extract of SAP at 37 ?C for 24 hours. No significant growth could be determined, i.e. the aqueous extract of SAP does not serve as an important additional carbon source, especially when a free water phase is lacking. Furthermore, cytotoxic effects of the extract could not be observed.

Additionally, the native product was tested against its resistance to microbiological attack and subsequent growth of microorganisms. Without addition of a culture medium, no growth was observed, i.e. SAP does not serve as an additional carbon source.

Inhibitory effects of extracts of SAP on the growth behavior of the potential pathogens E. coli and C. albicans were not observed, i.e. cytotoxic, cytostatic or biocidal effects are not to be expected. Furthermore, significant growth was not observed.

Production of bacterial toxin

Extracts and the gel of SAP were incubated with a TOXIC SHOCK SYNDROM TOXIN 1 (TSST 1) producing strain of Staphylococcus aureus to search for any abnormalities in the growth behavior of the microorganism and its ability to produce the toxin. The super absorbent polymer SAP exhibited no observed influence on the aforementioned parameters. (Laboratory for Toxicology & Ecology, Stockhausen, Germany)

Summary

SAP products are super absorbent polymers which exhibit a very low toxicological profile: Under appropriate test conditions there have been no signs of acute oral toxicity (> 5,000 mg/kg, rat) and acute dermal toxicity (> 2,000 mg/kg, rat). Furthermore, subacute oral toxicity and subchronic dermal toxicity have not been observed in rats. The eye irritative potency (rabbit) seems to be very low. SAP has a good compatibility following systemic injection or implantation and against blood. It is not per se cytotoxic. Absorption after oral uptake is negligible. Some absorption is observed after intratracheal application but without any systemic toxicity.

SAP shows no evidence of an allergic contact sensitization in guinea pigs and humans. The same applies for irritative properties. No mutagenic and teratogenic potency was found. SAP does not serve as a growth substrate for pathogenic microorganisms. However, chronic (2 year) inhalation of intentionally micronized fine dust of a super absorbent polymer caused tumor formation in rat lungs but in the highest concentration only. Therefore an occupational guidance value (OGV) of 0.05 mg/m3 is recommended by Neutra-Labs.

Conclusion:

Production and processing of SAP is devoid of any potential adverse effects to workers with direct contact to skin and mucous membranes is avoided (by protective cloth, goggles and gloves).
 
Usage of SAP in consumer products and technical articles has no negative effects on the health of consumers and users at all due to the low toxicity profile together with negligible exposure.
Dr. J. Haselbach Board Certified Toxicologist The German Society of Pharmacology & Toxicology (March 1995) (as edited by Dr. Richard Davis, Chief Medical Officer, Neutra-Labs, LLC, El Dorado Hills, CA 95762 ).
 
 

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