BES – Aquatic Toxicity Testing Results for Soilworks – One Product LC-50 Bioassay (TPD1106043)

1. 1.   INTRODUCTION

Soilworks of Chandler. Arizona requested Block Environmental Services (BES) to perform a 7 day chronic LC-50 bioassay on the synthetic dust control agent, Durasoil, using the mysid shrimp (Americomysis bahia).

BES received the product on April 13, 2011 and performed a multi-concentration toxicity test in order to determine a concentration-response curve for the mortality, LCS0 and IC25 endpoints.

The mull-concentration toxicity test consisted of five product concentrations (2000 mg/L, 1000 mg/L, 100 mg/L. IO mg/L. and 1 mg/L) and a laboratory control. run in eight replicates per concentration.

This report describes the procedures used and the results obtained for the aquatic toxicity test initiated on May 19, 2011.

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

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1. 2.    MATERIALS AND METHODS

2.1    SAMPLE AND TEST PREPARATION Sample 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 dispen:.er pipettes and clean glassware.

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

2.2    TOXJCITY 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 l-s:cological Effects Test Guidelines (OPPTS 850.1350 Mysid Chronic Toxicity Test)
  • Shon-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms (EPA/821/R-02/014.

2.2.2         Data Analysis

All toxicity testing results ,vere analyzed using the software program ToxCalc (Version  5.0). The software determines if there is a statistically significant reduction in response at the p Cc’.

0.05 level and uti Iizes the flowchart for statisticaI analysis outlined in EPA/82 l /R-02/01 3.

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

3, TESTING PARAMETERS

Table I: Summary of Testing Parameters

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1. 4.     RESULTS

4.1

A. bahia END POINT VALUES- Raw Daat   S ummary

* Statistically significant reduction compared to the Laboratory control (p”‘ 0.05)

Staf1sf1caI Ana1Iy. s1s S ummary

4.1.1                                                                                                                                                    Testing Notes

The Laboratory control water passed both the survival( 80%) and growth( 0.20 mg/surviving adult) test acceptability criteria.

The survival LC50 and growth IC25 values were hoth > 1000 mg/L.

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