Read Polymer in Aquatreat AR540 text version

File No: NA/921 22 April 2003

NATIONAL INDUSTRIAL CHEMICALS NOTIFICATION AND ASSESSMENT SCHEME (NICNAS)

FULL PUBLIC REPORT Polymer in Aquatreat AR540

This Assessment has been compiled in accordance with the provisions of the Industrial Chemicals (Notification and Assessment) Act 1989 (Cwlth) (the Act) and Regulations. This legislation is an Act of the Commonwealth of Australia. The National Industrial Chemicals Notification and Assessment Scheme (NICNAS) is administered by the Department of Health and Ageing, and conducts the risk assessment for public health and occupational health and safety. The assessment of environmental risk is conducted by the Department of the Environment and Heritage. For the purposes of subsection 78(1) of the Act, this Full Public Report may be inspected at: Library National Occupational Health and Safety Commission 25 Constitution Avenue CANBERRA ACT 2600 AUSTRALIA To arrange an appointment contact the Librarian on TEL + 61 2 6279 1161 or + 61 2 6279 1163. This Full Public Report is available for viewing and downloading from the NICNAS website or available on request, free of charge, by contacting NICNAS. For requests and enquiries please contact the NICNAS Administration Coordinator at: Street Address: Postal Address: TEL: FAX Website: 334 - 336 Illawarra Road MARRICKVILLE NSW 2204, AUSTRALIA. GPO Box 58, SYDNEY NSW 2001, AUSTRALIA. + 61 2 8577 8800 + 61 2 8577 8888. www.nicnas.gov.au

Director Chemicals Notification and Assessment

TABLE OF CONTENTS

FULL PUBLIC REPORT....................................................................................................................................... 3 1. APPLICANT AND NOTIFICATION DETAILS ................................................................................... 3 2. IDENTITY OF CHEMICAL ................................................................................................................... 3 3. COMPOSITION ...................................................................................................................................... 4 4. INTRODUCTION AND USE INFORMATION..................................................................................... 4 5. PROCESS AND RELEASE INFORMATION ....................................................................................... 5 5.1. Operation Description..................................................................................................................... 5 5.2. Occupational exposure.................................................................................................................... 5 5.3. Release............................................................................................................................................ 6 5.4. Disposal .......................................................................................................................................... 6 5.5. Public exposure............................................................................................................................... 6 6. PHYSICAL AND CHEMICAL PROPERTIES ...................................................................................... 6 7. TOXICOLOGICAL INVESTIGATIONS ............................................................................................... 8 7.1. Acute toxicity ­ oral ....................................................................................................................... 8 8. ENVIRONMENT .................................................................................................................................... 9 8.1. Environmental fate.......................................................................................................................... 9 8.2. Ecotoxicological investigations ...................................................................................................... 9 9. RISK ASSESSMENT ............................................................................................................................ 11 9.1. Environment ­ Exposure Assessment........................................................................................... 11 9.2. Environment ­ Effects Assessment .............................................................................................. 12 9.3. Environment ­ Risk Characterization........................................................................................... 12 9.4. Human health................................................................................................................................ 12 9.4.1. Human health - effects assessment .......................................................................................... 12 9.4.2. Occupational health and safety ­ risk characterisation ............................................................ 13 9.4.3. Public health ­ risk characterisation ........................................................................................ 13 10. CONCLUSIONS ­ ASSESSMENT LEVEL OF CONCERN FOR THE ENVIRONMENT AND HUMANS ........................................................................................................................................................ 13 10.1. Hazard classification..................................................................................................................... 13 10.2. Environmental risk assessment..................................................................................................... 13 10.3. Human health risk assessment ...................................................................................................... 13 10.3.1. Occupational health and safety ........................................................................................... 13 10.3.2. Public health........................................................................................................................ 14 11. MATERIAL SAFETY DATA SHEET............................................................................................. 14 11.1. Material Safety Data Sheet ........................................................................................................... 14 11.2. Label ............................................................................................................................................. 14 12. RECOMMENDATIONS .................................................................................................................. 14 12.1. Secondary notification .................................................................................................................. 14 13. BIBLIOGRAPHY ............................................................................................................................. 14

FULL PUBLIC REPORT Polymer in Aquatreat AR540

1. APPLICANT AND NOTIFICATION DETAILS APPLICANT(S) National Starch & Chemical Pty Ltd of 7 Stanton Road SEVEN HILLS NSW 2147. NOTIFICATION CATEGORY Limited: Polymer with NAMW 1000 (greater than 1 tonne per year). EXEMPT INFORMATION (SECTION 75 OF THE ACT) Data items and details claimed exempt from publication: chemical name and CAS number. VARIATION OF DATA REQUIREMENTS (SECTION 24 OF THE ACT) Variation to the schedule of data requirements is claimed as follows: absorption/desorption. PREVIOUS NOTIFICATION IN AUSTRALIA BY APPLICANT(S) None. NOTIFICATION IN OTHER COUNTRIES USA & Canada. 2. IDENTITY OF CHEMICAL MARKETING NAME(S) Aquatreat AR540 EXP-2288 MOLECULAR FORMULA (C3H4O2 C10H12O4S C4H8O3 C5H8O2 2Na)x x Na STRUCTURAL FORMULA

CH3 CH2 CH C O O

-

CH3 v CH2 C CH2 O S O

-

CH3 w CH2 O C C O CH3 x Na

+

u

CH2

C CH2 O

O

O S O O

-

MOLECULAR WEIGHT (MW) Number Average Molecular Weight (Mn) Weight Average Molecular Weight (Mw) Polydispersity Index (Mw/Mn) % of Low MW Species < 1000 % of Low MW Species < 500

4 961 15 277 3.08 3 0.67

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SPECTRAL DATA METHOD Remarks 3. Infra-Red; Gel Permeation Chromatography An IR spectrum was provided.

COMPOSITION DEGREE OF PURITY > 98.6% HAZARDOUS IMPURITIES/RESIDUAL MONOMERS None NON HAZARDOUS IMPURITIES/RESIDUAL MONOMERS (>1% by weight)

Chemical Name CAS No.

Water 7732-18-5

Weight %

44%

ADDITIVES/ADJUVANTS None. POLYMER CONSTITUENTS Chemical Name 2-Propenoic acid 2-Propenoic acid, 2-methyl-, methyl ester Benzenesulfonic acid, 4-[(2-methyl-2-propenyl)oxy]-, sodium salt 2-Propene-1-sulfonic acid, 2-methyl-, sodium salt Peroxydisulfuric acid (((HO)S(O)2)2O2), disodium salt Sodium hydroxide CAS No. 79-10-7 80-62-6 1208-67-9 1561-92-8 7775-27-1 1310-73-2

DEGRADATION PRODUCTS The polymer will degrade thermally. Above 240°C, various decomposition products will be formed including oxides of carbon and sulfur. LOSS OF MONOMERS, OTHER REACTANTS, ADDITIVES, IMPURITIES Unlikely to undergo ant depolymerisation. 4. INTRODUCTION AND USE INFORMATION MODE OF INTRODUCTION OF NOTIFIED CHEMICAL (100%) OVER NEXT 5 YEARS Import. MAXIMUM INTRODUCTION VOLUME OF NOTIFIED CHEMICAL (100%) OVER NEXT 5 YEARS Year Tonnes 1 10 2 <50 3 <50 4 <50 5 <50

USE The notified polymer will be used as a water treatment additive (calcium phosphate inhibitor) in water systems such as cooling towers and boilers.

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5. 5.1.

PROCESS AND RELEASE INFORMATION Operation Description The notified polymer will not be manufactured in Australia, but will be imported as the main component (56%) in Aquatreat AR540. The imported Aquatreat AR540 is packaged in 205 L tanks/drums or 1 000 L isotainers. After reformulation in Australia, the notified polymer in the final products will be <15% and packaged in 25 L or 100 L plastic containers. These final products will be further diluted during end use, the concentration of the notified polymer in the water system is estimated to be 2-20 ppm.

5.2.

Occupational exposure Transport and Storage Only a small number of personnel are likely to be involved in transporting Aquatreat AR540 following import and after reformulation. The containers will not be opened before arrival at the premises. It is not anticipated that transport and warehousing personnel will be exposed to the notified polymer, except in the case of an accident. Reformulation Reformulation of Aquatreat AR540 into a calcium phosphate inhibiting product will occur in Australia. Aquatreat AR540 will be mixed with other ingredients such as water, surfactants or other polymers, heated, cooled, and then packed into 25 or 100 L containers. The notified polymer will be reformulated in Australia at 10-15 water treatment chemical plants. Approximately 2-4 workers per reformulation site may be exposed to the notified polymer. As there are a limited number of water treatment companies in Australia, it is estimated that less than 30 process workers will be exposed to the notified polymer Australia-wide. Process workers will be involved in product reformulation, quality control and packaging. Since the vapour pressure of the notified polymer is low, skin would be the main route of occupational exposure. Ocular exposure is also possible. Dermal exposure may occur for formulation operators and fillers from drips and spills when transferring Aquatreat AR540 to the mixing tanks and transferring the reformulated product to the storage containers. The maximum concentrations of the notified polymer that the formulation operators and fillers will handle are 56% and <15%, respectively. Dermal exposure is also possible during quality control activities. However, quality control workers will only handle small quantities. Aquatreat AR540 will be pumped directly from the import containers into an enclosed, mixing tank, using a dedicated pump and hose system. Mechanical ventilation with local exhaust is fitted at formulation sites. The notifier expects that workers exposed to the notified polymer would wear appropriate personal protective equipment, including safety goggles and impervious/rubber gloves, overalls and safety boots. End Users The list of potential customers using the reformulated end product is extensive but could include any industry using steam, high-pressure water, or cooling towers, such as large office buildings utilising cooling towers for air conditioning purposes, and the paper processing and mining industry. A large number of workers would be exposed to the reformulated product containing the notified polymer when handling the drums, removing bungs and connecting pumping equipment to their water systems. The maximum concentration of the notified polymer these workers will be exposed to is 15%. The final concentration of the notified polymer in the water system is estimated to be between 2 and 20 ppm. An automated dosing system will be used to add the reformulated product to the water systems, thus minimising dermal exposure from drips and spills. Dermal contamination is considered to be the main

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routine of occupational exposure for end users. Exposure duration for workers is expected to be limited to the time taken to change containers in the automated dosing system. It is recommended that workers should wear gloves and eye protection when handling the notified polymer. 5.3. Release RELEASE OF CHEMICAL AT SITE Release of the notified polymer into the environment could occur in the event of a spill during transport or reformulation of the product in the workplace. The notifier recommends that all spills be cleaned up with inert material such as diatomaceous earth and disposed of as solid waste by a licensed waste contractor according to regulations. Release of the notified polymer may occur during reformulation through container washing. To avoid unnecessary waste, the notifier recommends that any empty containers be washed out and the material reused in the mixing and reformulation process. Similarly, empty containers of the reformulated product should be washed and any residuum in containers reused in boilers and cooling towers. The cleaned containers can then be either recycled or disposed of as non-hazardous waste. If customers choose not to recycle the residual, it is expected that each unwashed 205 litre drum may contain 0.5% of residual polymer. Assuming an import volume of 50,000 kg per year, up to 250 kg may be retained as residue in containers. It is expected that these residues will be disposed of to landfill through disposal of containers in industrial waste. RELEASE OF CHEMICAL FROM USE The main source of release of the polymer to the environment is expected to occur as a result of discharge of water containing the scale inhibitor product from boilers and cooling towers during their normal operations. Over 99% of the polymer is likely to enter the environment in this manner. Boiler blow down occurs approximately every shift under normal operations of a boiler. Hence release is expected to occur on a daily basis. It is estimated that about 20 ppm of the notified polymer will be released by way of blow downs each shift. This value assumes a recommended dosing rate of about 100 ppm of product, of which 15% is notified polymer. The value also assumes that some residual concentration of the scale inhibitor remains in the boiler system before discharge. The water released from these systems is expected to enter the waste effluent stream at each facility. 5.4. 5.5. Disposal Wastes from spills and container residues are either recycled or disposed of as non-hazardous waste. Public exposure Exposure of the general public as a result of reformulation, transport and disposal of the product containing the notified polymer is assessed as being negligible. The product containing the notified polymer is for industrial use only. It will not be used by the general public in domestic situations. 6. PHYSICAL AND CHEMICAL PROPERTIES Data of physical and chemical properties were generated from Aquatreat AR540, which contains 56% notified polymer, unless specified otherwise. The methods described in this section are summarised from unpublished and largely undated notes and analytical test reports provided in the dossier by the Alco Analytical Research Laboratory at Chattanooga, USA, unless referenced otherwise. The flash point, flammability limits and autoignition temperature of the notified polymer were not determined. The notified polymer is expected to dry and then char upon heating. The char can be considered combustible. Appearance at 20oC and 101.3 kPa Clear, dark brown, aqueous solution.

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Melting Point/Freezing Point Remarks

Not determined.

The notified polymer has a viscosity of <2500 centipoise per second. The viscosity increases until the water freezes, which would interfere with pour point or glass transition state measurements. Not determined. The boiling point of the notified polymer cannot be determined using OECD testing methods because the polymer does not exhibit a conventional boiling point. Upon heating the water vaporises leaving a hard, solid mass which chars as the temperature is increased. 1 190 kg/m3 at 20oC. OECD TG 109 Density of Liquids and Solids. SafePharm (2000a). 6.2 x 10-8 kPa at 25°C. OECD TG 104 Vapour Pressure. EC Directive 92/69/EEC A.4 Vapour Pressure. The vapour pressure (VP) of the notified polymer was determined using a vapour pressure balance system. Determination involved measuring the change in mass of the polymer placed under a vacuum when subject to temperatures between 200 and 235ºC. Three series of mass difference readings were taken at time intervals beginning at 0 hours, 2 hours, and 5 hours after heating. A regression slope was calculated using measurements taken during run 3 (at 235ºC) at which time the sample had been under vacuum for the longest period, ensuring degassing was complete. Extrapolation of the data to 25ºC gave a VP of 6.132 x 10-5 Pa, indicating the polymer is not volatile at 25ºC. SafePharm (2000b). Infinite solubility at 25°C. No numerical values for water solubility or saturation equilibrium are given in the notification dossier. Notes provided in the dossier state that the notified polymer is infinitely soluble in water. If the polymer is added to water as described in OECD Method 105, it will first dissolve and form a true solution. As more of the polymer is added, the solution will begin to thicken and then first form a colloidal solution and then a gel. Finally, as available water becomes limiting, a moist mass of polymer will form. This phenomenon has been documented in the literature (c.f. Vold and Vold, 1949; Morawetz, 1975). T1/2 at pH 4.0, 7.0, 9.0 > 1 year

Boiling Point Remarks

Density METHOD TEST FACILITY Vapour Pressure METHOD Remarks

TEST FACILITY Water Solubility Remarks

Hydrolysis as a Function of pH Remarks

A preliminary test for Hydrolysis as a Function of pH was performed at ALCO Analytical Research Laboratories according to OECD Method 111. Analysis was performed at pH 4, 7, and 9, and a temperature of 50ºC, using solutions of sterile water with 0.5% (w/w) concentrations of AR-540. GPC analysis after 7 days showed no change in the distribution of molecular weight species, indicating no decomposition of the polymer over the test period. Log Pow = -0.99 at 23oC.

Partition Coefficient (n-octanol/water) Remarks

The partition coefficient of the polymer was determined using the Shake Flask Method (OECD Method 107). The pH of the partitioning solution was set with HCL to pH 3.0, which is 1 pH point below the dissociation constant of the carboxyl

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and sulfonate groups. The stock partitioning mixture was prepared using 32.85 g/L of polymer. Equilibrations were carried out in 50 mL centrifuge tubes at 23ºC. Three sets of duplicate samples were prepared, containing 1:1, 1:2, and 2:1 ratios of octanol to water, respectively. Vials were mixed for 30 minutes then centrifuged until phase separation occurred. Water was removed from the bottom layer of the tube with a syringe for HPLC analysis. The amount of the notified polymer in noctanol was determined by subtracting the measured concentration in water from the initial concentration in each test vial. The partition coefficient was determined from an average of 6 analysis. The Pow, was determined to be 0.1031, indicating the polymer has a relatively poor affinity to lipids (van Leeuwen and Hermens, 1995). Adsorption/Desorption Remarks Not determined.

The adsorption coefficient was not determined. However, the notified polymer is expected to strongly adsorb to soils and sediments in the environment given its chelating ability. Function groups have pKa < 0.6; or pKa = 4 ­ 4.9. The dissociation constant of the notified polymer was not determined by OECD methods, but rather was modelled for individual functional group on the notified polymer using the dissociation constants of similar or related functional groups listed in Dean (1987). It was concluded that the polymer should have several pKa's <0.6 due to the sulfonic acid/sulfonate groups, and several pKa's between 4.0 and 4.9 due to the different arrangements of carboxylic acid/carboxylate groups on the polymer backbone. Not determined. Not determined for a water soluble polymer. Not determined. Not determined for a water soluble polymer. Not determined. Not determined for a water soluble polymer. Not determined.

Dissociation Constant Remarks

Particle Size Remarks Flash Point Remarks Flammability Limits Remarks

Autoignition Temperature Remarks Explosive Properties Reactivity

Not determined for a water soluble polymer. The notified polymer has no explosive properties that could result from exposure to heat, shock or friction. Incompatible with material known to react with water.

7.

TOXICOLOGICAL INVESTIGATIONS

Summary of the acute toxicity of the polymer in Aquatreat AR540 Endpoint and Result Rat, acute oral LD50 > 2 000 mg/kg bw 7.1. Acute toxicity ­ oral Assessment Conclusion low toxicity

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TEST SUBSTANCE METHOD Species/Strain Vehicle RESULTS Group

Notified polymer OECD TG 401 Acute Oral Toxicity ­ Limit Test. Rat/Sprague Dawley Water

Number and Sex of Animals 5/sex

Dose mg/kg bw 2 000

Mortality None.

LD50 Signs of Toxicity

> 2 000 mg/kg bw Clinical signs after treatment were observed in not more than 4 animals/sex and comprised soft and watery faeces, sparse hair, skin and hair discoloration, and material around noses and mouths. These signs appeared intermittently and generally subsided during the observation period. There were no test substance related effects on body weight gains. No test substance related macroscopic abnormalities were observed at necropsy. The notified chemical is of low toxicity via the oral route. MPI Research (1999).

Effects in Organs CONCLUSION TEST FACILITY 8. 8.1. ENVIRONMENT Environmental fate

No biodegradation data were provided. Data are not required by the Act. 8.2. Ecotoxicological investigations

The notifier provided ecotoxicity test studies for fish, Daphnia and algae. The results of these tests are summarised in the table below. All tests were performed in compliance with OECD/EEC Test Methods and according to OECD Principles of Good Laboratory Practice, unless otherwise stated. Test Acute Toxicity to Fish Test (OECD TG 203) Acute Toxicity to Daphnia Test (OECD TG 202) Acute Toxicity to Algae Test (US EPA 1996) Species Fathead Minnow Pimephales promelas Water Flea Daphnai Magna Freshwater Algae Selenastrum capricornutum Results 96h LC50 >1 000 mg a.i./L NOEC = 1 000 mg a.i./L 48h LC50 = 837 mg a.i./L NOEC = 360 mg a.i./L 96h EC50 = 25 mg a.i./L 96h EC10 = 13 mg a.i./L 96h EC90 = 57 mg a.i./L NOEC = 10 mg a.i./L

* NOEC - no observable effect concentration Fish A static acute toxicity limit test (OECD TG 203) was conducted over 96 hours against a total of 30 juvenile Fathead Minnows (ie. 10 fish x 3 replicates for each treatment and control group) using nominal concentrations of 0 (control) and 1 000 mg/L active ingredient of the notified polymer. Individual test solutions were prepared by adding aliquots of a stock solution containing 80.65 mg/mL of the notified polymer to dilution water in each

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test chamber to achieve a final concentration of 2240 mg/L, equivalent to 1 000 mg/L active ingredient (Wildlife International, 1998a). The tests were carried out in well water taken from a 40 metre deep well. The well water was first filtered to remove particles >25 µm, and then passed through a millipore (0.2 µm) filter to remove microorganisms and fine particles. During the test, the water temperature was maintained at 22 ±1°C over the test period. Dissolved oxygen levels were in excess of 87% saturation of solution, pH levels were between 5.9 and 8.2, and total hardness was 128 mg/L CaCO3. Concentrations of the notified polymer in the test media were confirmed at 0, 48 and 96 hours by UV spectrophotometric analysis and were found to be within ­2.3 and 1.7% of target values. The fish were observed at intervals over the test period. All fish appeared normal and healthy throughout the test period. There were no mortalities among fathead minnows, in either the control group or in the treatment group exposed to 1000 mg a.i./L of test material at the end of the test period. Daphnia A static acute toxicity test (OECD TG 202) was conducted over a 48 hour period against 20 Daphnia magna per test concentration using a control (0), and a geometric series of 5 nominal test concentrations: 130, 216, 360, 600 and 1 000 mg/L of the notified polymer. Individual test solutions were prepared by adding aliquots of a stock solution containing the notified polymer to dilution water in each test chamber to achieve the final concentrations of notified polymer (Wildlife International, 1998b). The tests were carried out in filtered well water derived from a well approximately 40 metres deep. The water temperature was maintained at 20 ±1°C over the test period. Dissolved oxygen levels were in excess of 96% of saturation, pH levels were between 6.0 and 8.5, and total hardness was 132 mg/L CaCO3. Concentrations of the notified polymer in the test media were confirmed at 0 and 48 hours using UV spectrophotometric analysis and were found to be within 99 and 101% of nominal target values. No mortalities or immobile organisms were observed in the control group at the end of the test, and all daphnids appeared normal throughout the test. Cumulative percent mortality/immobility in the 130, 216, 360, 600 and 1 000 mg a.i./L treatment groups at test termination was 5%, 5%, 0%, 15%, and 70%, respectively. The daphnid mortalities occurring in the 130 and 216 mg a.i./L treatment groups were not dose-responsive, and hence were thought to be due to causes other than the toxicity effects of the test substance. Mortalities (and lethargy) observed in the daphnids exposed to the 600 and 1 000 mg a.i./L treatment groups were dose-responsive, increasing with increases in polymer concentration, and hence were considered due to the toxic effects of the notified polymer. Algae A 96-hour acute toxicity test (US EPA 1996) was conducted against 1 x 104 cells/mL of freshwater algae using nominal concentrations of 0 (control) 5, 10, 20, 40, and 80 mg/L notified polymer. The algal cells were cultured in test medium containing a stock nutrient solution and well water, purified by reverse osmosis. The test chamber temperature was held at 24 ±2°C and under a light intensity of 4 300 ±430 lux. The pH values of the test medium ranged from 6.1 to 7.4 on Day 0, and from 6.5 to 8.9 on Day 4 (Wildlife International, 1998c). Changes in mean cell densities were used to calculate the percentage inhibition of algal growth in the test medium exposed to the notified polymer relative to algal growth in the control medium. Cell densities indicated exponential growth of algal cells occurred in the control replicates over the test period. At 96 hours, there were no significant differences in cell densities between the control and the treatment groups of algae exposed to 5 and 10 mg a.i./L of the notified polymer. However, at 96 hours, mean cell densities in the treatment groups of algae exposed to 20, 40 and 80 mg/L a.i. of notified polymer were inhibited by 32, 85, and 95% respectively. The inhibition was statistically significant, with maximum inhibition occurring at concentrations of 80 mg/L a.i. Inhibition was not associated with any noticeable changes in cell colour, size or morphology, or any visual evidence of clumping, flocculation or adherence of algae to the test chamber. After 96 days, the 80 mg/L a.i. treatment group was diluted to a concentration of 1.2 mg/L a.i. with algal medium and cultured for a further 4 days to allow recovery. On the basis of cell morphologies and cell density in the recovery phase, it was concluded the effects of the notified polymer were algistatic rather than algitoxic due to the chelation of micronutrients metals in the test water.

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9. 9.1.

RISK ASSESSMENT Environment ­ Exposure Assessment

Usage patterns indicate that over 99% of the notified polymer will be released into the aquatic environment via sewage treatment systems predominantly through discharge of water during boiler blow downs and from water cooling towers. Worst case scenario Predicted Environmental Concentrations (PEC) of the notified polymer released after direct discharge into the sewer of a large city and a medium sized town are shown in the table below (following the method of Klaine et al. 1996). A: Import volume (year 5) B: Daily release C: Application Concentration D: Daily flow of cooling towers (B/C) E: Sewer Rate per Day F: Dilution Factor in sewer (E/D) G: Concentration in Sewer (C/F) H: Dilution Factor in Receiving waters I: Concentration in Receiving Waters (G/H) City 50 000 kg 137 kg 20 mg/L 6ML 250ML 36.2 0.55 mg/L 10 0.055 mg/L Town 5000 kg 13.7 20 mg/L 0.68 ML 7.5ML 11 1.8 mg/L 3 0.6 mg/L

In determining the PEC values, the following assumptions were made: · Application rates are 20 mg/L of notified polymer. · All 50,000 kg of chemical imported in one year is released into the sewer over a 365 days period, with no chelation or adsorption prior to release. · All release occurs in one city (approximately 1.7 million people), or in one country town (50,000 people), with a sewer output based on an average water usage of 150 L per day per person. Environmental Fate The polymer is composed of copolymers forming a linear chain and with a large number of anionic side-groups per polymer chain acting as multiple ligands. These give the polymer the ability to chelate metal cations and to bind to microcrystallites. Hence, when the notified polymer enters sewage treatment facilities, some of the chelation potential will be reduced due to loading of active sites with Ca2+, Mg2+ or other cations in the cooling system. However, the chelating potential of the polymer is not expected to be fully exhausted upon release (PFA, undated). In the sewage treatment facility, any active sites remaining will strongly adsorb to cations or suspended sediment residing in the water compartment. The high molecular weight polymers are then expected to be eliminated either by settling in clarification tanks or by adsorption onto organic biomass (Opgenorth, 1992). The polyacrylate in the polymer is not expected to degrade readily in activated sewage sludge given the polymers high molecular weight (Opgenorth, 1992; Larson et al. 1997). However, selective removal by biodegradation of high molecular weight polymers is possible. In an unpublished report included in the dossier, it was indicated the side chains on the polymer are likely to be susceptible to biotic breakdown resulting in partial degradation of the polymer. The sequencing of the copolymers is not known, but the rate of degradation is expected to be more rapid if the dominant polyacrylate fragments are broken up by other monomers, since polymer chains containing fewer repeat units are more easily degraded (PFA, undated). Release of the polymer into the soil environment will depend on the means of disposal of the sewage sludge. If the sewage sludge is sent to landfill, or is used for agricultural purposes, it is expected that the polymer will become fixed to soil particles and remain in the upper soil horizons. Adsorption onto soil particles will render the polymer immobile and hence no leaching of the polymer to the groundwater compartment is expected (Opgenorth, 1992). The new polymer is not expected to readily degrade in the soil environment. For example, no decomposition of the polymer occurred during the hydrolysis test at pH ranges typically found in the environment. Chemicals with a long residence time in soils, indicated by a half-life of greater than 1 year, have the potential to accumulate in the environment. However, microorganisms existing in soil environments are able to utilise organic compounds for energy. Many of these organisms have the ability to acclimatise to xenobiotic

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compounds (van Leeuwin and Hermens, 1995). Hence, it is anticipated that slow mineralisation of the notified polymer by microorganisms is likely to occur. The polymer is not expected to bioaccumulate given its low Pow and high molecular weight. 9.2. Environment ­ Effects Assessment

The ecotoxicity data indicate the notified polymer is not harmful to fish or Daphnia, but is able to inhibit the growth of algae (EC50 = 25 mg/L) and is considered slightly toxic to these organisms (Mensink et al., 1995). The inhibition of algal cell growth is considered to result from the notified polymer sequestering critical micronutrient metals in the growth medium, and hence starving the algae. This phenomenon has been documented for other scale inhibitor substances as well (eg. Schowanek et al., 1996). Schowanek et al. (1996) suggest that both NOEC and EC50 values given by algal growth inhibition tests may be overestimated by at least one order of magnitude for strong chelating chemicals. 9.3. Environment ­ Risk Characterization

The polymer is not expected to pose a significant threat to aquatic organisms, including algae, when released into the environment in small quantities. The worst case scenario PEC values in a city and a town are significantly lower than the EC50 values for both fish and Daphnia, and are within an order of magnitude lower than the EC50 for freshwater algae. The PEC values are likely to be overestimated. In reality, a large portion of the polymer will be removed in the sewage treatment facilities by adsorption and settling, leaving only a small amount associated with the water compartment. The small amount of polymer released into surface water will likely have many of the active sites already loaded with Ca2+, Mg2+ and other ions scavenged from the nutrient-rich sewage effluent still further reducing its scavenging capabilities in natural environments. In addition, release of the imported volume of polymer is expected to be much more diffuse than is assumed in calculating the PEC values. Release will occur in cities and towns nationwide, rather than be restricted to one city or town. Ultimately, most of the polymer will be disposed with solid waste left following sewage treatment. Most sewage sludge in Australia is dried and either sent to landfill or incinerated (ash may be sold to farmers), but with sludge increasingly being used as soil conditioners and fertilisers in industries such as agriculture, horticulture and land rehabilitation (Beretka and Whitfield, 1993; Sydney Water, 2000). In soil environments, the polymer is expected to eventually undergo slow mineralisation by microorganisms. While no toxicity data were provided for soil organisms, no adverse effects on soil organisms have been reported for similar substances (ie. polycarboxylates) in the concentration range up to 10000 or 1600 mg/kg of soil (Opgenorth, 1992). Sewage sludges contain appreciable amounts of toxic heavy metals including arsenic, lead, cadmium, and mercury. Restricting inputs in effluent is desirable to reduce these unwanted elements (Tiller, 1989), especially if sludge is being used as a soil conditioner. Scavenging of heavy metals ions such as Zn2+, Cd2+ and Hg2+ from water treatment vessels, pipes, etc, by the notified polymer could conceivably contribute to the heavy metal load in sewage sludge from treatment facilities. Additionally, any remaining active sites on the polymer may adsorb heavy metals already residing in sludge (Bubb and Lester, 1991). However, heavy metal contamination of soils resulting from the presence of the notified polymer in sewage sludge is not expected to be significant given the low concentrations and anticipated nationwide use of the polymer. 9.4. 9.4.1. Human health Human health - effects assessment Since the notified polymer has a high NAMW with low contents of low molecular species and residual monomers, it is not likely to cross biological membranes. Aquatreat AR540 containing

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56% notified polymer has very low acute oral toxicity in rats. No information was supplied on other toxicological end points. The MSDS supplied for Aquatreat AR450 states that it is a moderate eye irritant and prolonged or frequent contact may irritate the skin. The MSDS also indicates that it contains a skin sensitiser and ingestion may cause nausea and vomiting. 9.4.2. Occupational health and safety ­ risk characterisation Transport and warehouse personnel are unlikely to be exposed to the notified polymer. The occupational health risk posed to these workers is therefore considered negligible. Although dermal and eye exposure to drips, splashes and spills is expected to be low, it is most likely to be the predominant route of exposure for workers involved in reformulating the imported product. Inhalation exposure is expected to be minimal because the notified polymer has a low vapour pressure and is not used in a manner that will generate aerosols. Aquatreat AR540 will be reformulated at a limited number of companies in Australia, and the reformulation process will take place in an enclosed, vented mixing tank. Process workers exposed to the notified polymer will wear appropriate personal protective equipment, including overalls, eye protection and gloves to reduce any risk of adverse effects. End use workers may be exposed to the notified polymer at a maximum concentration of 15%. Skin exposure is possible during addition of the reformulated product to the water systems, but will be limited, as an automated dosing system will be used for this task. It is recommended that gloves and eye protection be worn during addition of the notified polymer to the water system to minimise health risk. Aquatrreat AR540 may contain small amount of residual monomers acrylic acid and methyl methacrylate. Both are irritants with NOHSC exposure standards of 2 ppm TWA and 100 ppm TWA, respectively. Both can be absorbed through the skin and methyl methacrylate is a skin sensitiser. Therefore precautions are required to reduce the risk of skin and eye effects. 9.4.3. Public health ­ risk characterisation Exposure of the general public as a result of reformulation, transport and disposal of the product containing the notified polymer is assessed as being negligible. The product containing the notified polymer is for industrial use only. It will not be used by the public in domestic situations. The risk to public health is considered to be minimal since public exposure is unlikely as a result of the industrial uses of products containing the notified polymer. 10. CONCLUSIONS ­ ASSESSMENT LEVEL OF CONCERN FOR THE ENVIRONMENT AND HUMANS

10.1. Hazard classification Based on the available data the notified chemical is not classified as hazardous under the NOHSC Approved Criteria for Classifying Hazardous Substances. 10.2. Environmental risk assessment The chemical is not considered to pose a risk to the environment based on its reported use pattern. 10.3. Human health risk assessment 10.3.1. Occupational health and safety There is Low Concern to occupational health and safety under the conditions of the occupational settings described.

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10.3.2. Public health There is Negligible Concern to public health based on its reported use pattern. 11. MATERIAL SAFETY DATA SHEET

11.1. Material Safety Data Sheet The MSDS of the notified polymer provided by the notifier was in accordance with the NOHSC National Code of Practice for the Preparation of Material Safety Data Sheets (NOHSC, 1994a). It is published here as a matter of public record. The accuracy of the information on the MSDS remains the responsibility of the applicant. 11.2. Label The labels for the notified polymer and products containing the polymer provided by the notifier were in accordance with the NOHSC National Code of Practice for the Labelling of Workplace Substances (NOHSC, 1994b). The accuracy of the information on the label remains the responsibility of the applicant. 12. RECOMMENDATIONS REGULATORY CONTROLS Labelling · Use the following safety phrase for Aquatreat AR540 containing the notified chemical: - Avoid skin and eye contact.

CONTROL MEASURES Occupational Health and Safety · Employers should ensure that the following personal protective equipment is used by workers to minimise occupational exposure to the notified polymer: - Chemical impervious gloves - Industrial overalls - Eye protection or face shield. Guidance in selection of personal protective equipment can be obtained from Australian, Australian/New Zealand or other approved standards. · · A copy of the MSDS should be easily accessible to employees. If products and mixtures containing the notified polymer are classified as hazardous to health in accordance with the NOHSC Approved Criteria for Classifying Hazardous Substances, workplace practices and control procedures consistent with provisions of State and Territory hazardous substances legislation must be in operation.

12.1. Secondary notification The Director of Chemicals Notification and Assessment must be notified in writing within 28 days by the notifier, other importer or manufacturer: (1) Under Subsection 64(2) of the Act: - if any of the circumstances listed in the subsection arise.

The Director will then decide whether secondary notification is required. No additional secondary notification conditions are stipulated. 13. BIBLIOGRAPHY

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Beretka J and Whitfield D (1993) Survey of Industrial Process Wastes and By-Products Generated in Australia. CSIRO Australia; University of Western Sydney. Bubb JM and Lester JN (1991) The Impact of Heavy Metals on Lowland Rivers and the Implications for Man and the Environment. The Science of the Total Environment, 100: 202-233. Dean JA (1987) Lange's Handbook of Chemistry, 13th edition. McGraw Hill Book Company, New York, pp 518. Klaine SJ, Cobb, GP, Dickerson RL Dixon, KR, Kendell RJ, Smith EE and Solomon KR (1996) An ecological risk assessment for the use of the biocide, dibromonitrilopropionamide (DBNPA), in industrial cooling systems. Environmental Toxicology and Chemistry, 15 (1):21-30. Larson RJ, Bookland EA, William, RT, Yocom KM, Saucy DA, Freeman MB, and Swift G. (1997) Biodegradation of acrylic acid polymers and oligomers by mixed microbial communities in activated sludge. Journal of Environmental Polymer Degradation, 5(1):41-48. Mensink BJWG, Montforts M, Wijkhuizen-Maslankiewicz L, Tibosch H and Linders JBHJ (1995) Manual for summarising and evaluating the environmental aspects of pesticides. National Institute of Public Health and Environmental Protection. Bilthoven, The Netherlands. Morawetz H (1975) High Polymers Vol. XXI, 2nd Edition, Macromolecules in Solution. John Wiley & Sones, Inc. New York. p305. MPI Research (1999) An acute oral toxicity study of Aquatreat-AR540 in rats. MPI Research, Mattawan (Unpublished report provided by notifier). NOHSC (1994a) National Code of Practice for the Preparation of Material Safety Data Sheets [NOHSC:2011(1994)]. National Occupational Health and Safety Commission, Canberra, Australian Government Publishing Service. NOHSC (1994b) National Code of Practice for the Labelling of Workplace Substances [NOHSC:2012(1994)]. National Occupational Health and Safety Commission, Canberra, Australian Government Publishing Service. NOHSC (1999) Approved Criteria for Classifying Hazardous Substances [NOHSC:1008 (1999)]. Canberra, Australian Government Publishing Service. Opgenorth HJ (1992) Polymeric materials polycarboxylates. In: Hutzinger, O (editor), The Handbook of Environmental Geochemistry, Volume 3 Part F: Anthropogenic Compounds, Detergents (N.T. de Oude, volume editor). Pp. 338-350. Springer-Verlag Berlin Heidelberg. PFA (undated) Environmental fate of AR-540. Peter Fisk Associates (Unpublished report provided by notifier) SafePharm (2000a) AQUATREAT AR-540-D: Determination of density. SPL Project Number: 1429/001. 23 November 2000. SafePharm Laboratories, Derby, UK. (Unpublished report provided by the notifier). SafePharm (2000b) AQUATREAT AR-540-D: Determination of Vapour Pressure. SPL Project Number: 1429/002. 27 November 2000. SafePharm Laboratories, Derby, UK. (Unpublished report provided by the notifier). Schowanek D, McAvoy D, Versteeg D and Hanstveit A (1996) Effects of nutrient trace metal speciation on algal growth in the presence of the chelator [S,S]-EDDS. Aquatic Toxicology 36:253-275. Sydney Water (2000) Annual Environment & Public Health Report 2000. Beneficial Use of Biosolids from Sewage Treatment (http://www.sydney water.com.au). Tiller KG (1989) Heavy Metals in Soils and Their Environmental Significance. Advances in Soil Science, Volume 9, pp113-142. Springer-Verlag.

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U.S. Environmental Protection Agency (1996). Series 850-Ecological Effects Test Guidelines (draft), OPPTS Number 850.5400: Algal Toxicity, Tiers I and II. van Leeuwen CJ and Hermens JLM (1995) Risk Assessment of Chemicals: An Introduction. Kulwer Academic Publishers. Vold RD and Vold MJ (1949) Physical Methods, Part 1. In: A Weissberger (editor), Techniques in Organic Chemistry, Volume 1, 2nd Edition, Interscience Publishers Inc., New York. p81. Wildlife International (1998a) AQUATREAT AR-540: A 96-hour static acute toxicity test with the Fathead Minnow (Pimephales promelas). Final Report. Wildlife International Ltd. Project Number: 310A-123. June 29, 1998. Easton, Maryland. USA. (Unpublished report provided by the notifier). Wildlife International (1998b) AQUATREAT AR-540: A 48-hour static acute toxicity test with the Cladoceran (Daphnia magna). Final Report. Wildlife International Ltd. Project Number: 310A-122. June 29, 1998. Easton, Maryland. USA. (Unpublished report provided by the notifier). Wildlife International (1998c) AQUATREAT AR-540: A 96-hour toxicity test with the Freshwater Alga (Selenastrum capricornutum). Final Report. Wildlife International Ltd. Project Number: 310A-124. October 22, 1998. Easton, Maryland. USA. (Unpublished report provided by the notifier).

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