BES – Aquatic Toxicity Testing Results for Soilworks – One Product LC-50 Bioassay Using Oncorhynchus mykiss (TPD1105041)

1. 1.    INTRODUCTION

Soilworks of Chandler, Arizona requested Block Environmental Services (BES) to perform a 96- Hr LC-50 aquatic bioassay on the synthetic dust control agent, Durasoil™, using the rainbow trout (Oncorhynchus mykiss).

BES received the product on April 13, 2011 and performed a multiconcentration toxicity test in order to determine a concentration-response curve for the mortality and LC-50 endpoint.

The multi-concentration toxicity tests consisted of five product concentrations (2000 mg/L, I 000 mg/L, 100 mg/L, 10 mg/L, and I mg/L) and a Laboratory control, run in duplicate.

This report describes the procedures used and the results obtained for the aquatic toxicity test initiated on May 12, 2011.

BES is an Environmental Laboratory Accreditation Program certified laboratory (#1812).

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1. 2.    MATERIALS AND METHODS

2.1    SAMPLEANDTESTPREPARATIONSample identification – Durasoil™

Chemical name: Synthetic Organic Dust Control Agent Appearance and odor: Colorless, odorless

Solubility: Insoluble in water

The sample was received on April 13, 2011 and stored at ambient room temperature for the duration of the study.

Samples to set up the definitive tests were weighed out using a Sartorius Balance, disposable dispenser pipettes and clean glassware.

A summary of testing parameters by organism can be found in Table 1.

2.2    TOXICITY TEST PROCEDURES

2.2.1        Test Procedures -A detailed procedure for this test is outlined in laboratory standard operating procedures (SOPs) kept at the BES laboratory and they are based upon the following reference:

• EPA Ecological Effects Test Guidelines (OPPTS 850.1075 Fish Acute Toxicity Test, Freshwater and Marine).
• Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms, 5^th Edition (EPA/821/R-02/012).

2.2.2         Data Analysis

All toxicity testing results will be analyzed using the software program ToxCalc (Version 5.0).   This program determines if there is a statistically significant reduction in response at the p = 0.05 level and utilizes the flowchart for statistical analysis outlined in EPA/821/R-02/013. The testing compared the sample responses with the laboratory

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control water. The parameters of interest for the effluent tests are the Lethal (LC) and Inhibition (IC) Concentrations. The LC/IC values will show the point estimate of the toxicant concentration that causes a given percent reduction.

1. 4.      TESTING PARAMETERS

Table 1: Summary of Testing Parameters

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1. 5.     RESULTS

5.1    Oncorhynchus myldss END POINT VALUES –

Table 2: Range Finding Test Results

5.2                                                                                                                                       Testing Notes

The Laboratory control water passed the test acceptability criteria (2:,90% survival).

The survival LC50 value was> 2000 mg/L.

6 CONCLUSION

• 0. mykiss survival was not adversely effected by the product at any of the test concentrations ofDurasoil™. The LC50 ofDurasoil™ for this test organism is

>2000 mg/L

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BLOCK ENVIRONMENTAL SERVICES

96 Hr Acute Static Test Data Sheet