Open literature Review Summary

Chemical Name: Atrazine

CAS No: 1912-24-9

ECOTOX Reference Number and Citation: 166446 Dornelles M.F. and G.T. Oliveira. 2014. Effect of Atrazine, Glyphosate and Quinclorac on Biochemical Parameters, Lipid Peroxidation and Survival in Bullfrog Tadpoles ( Lithobates
catesbeianus ). Arch. Environ. Contam. Toxicol. 66(3): 415-429.

Purpose of Review: Registration Review

Date of Assessment: 10/23/2015

Brief Summary of Study Findings: This study examined the effects of atrazine at 5, 10 and 20

μ g/L on bullfrog tadpoles (Lithobates catesbeianus ) on biochemical parameters, lipid peroxidation and survival. Biochemical paramete rs analyzed included glycogen, total lipids, triglycerides, cholesterol and total proteins in liver, gill and muscle. Atrazine exposure induced significant changes in all biochemical paramete rs analyzed and increased lipid peroxidation levels, with significant impacts to glycogen stores in all compartments. No significant changes in growth or survival in treatment groups as compared to controls were noted at the end of 14 days.

Methods: Live tadpoles were acquired from a commercial frog at 4 months of age and were in the larval Gosner stage 26 according to Gosner (1960). Animals were placed in 22 aquariums each containing 12 L of water (n = 12), with constant aeration, ĂǁĂƚĞƌƚĞŵƉĞƌĂƚƵƌĞŽĨϮϮцϮ  ͕ pH 6.2 ± 0.3, and a 12-h light-to-dark cycle. The tadpoles were fed (5 % of their biomass) once daily with the same fish feed used in the commercial frog farm. Animals were acclimated for 7 days with exposure occurring on day 8. Experimental design consisted of two replicates for each exposure concentration of 5, 10 and 20 ug/L atrazine. Commercial formulation of atrazine was used (Primo ́leo, 400 g/L; Syngenta). The exposure period was 7 days with atrazine being applied only once in liquid formulation and dissolved in distilled water. Animals were sacrificed b the freezing method in treatment groups at day 14 and in control groups at days 7 and 14. Left and right gills, liver and muscle were removed and ti ssue specimens were then used for biochemical analysis of the levels of glycogen, total protein, lipids, cholesterol, and triglycerides as well as evaluation of lipid peroxidation levels for each treatment level and controls.

Results: Significant differences (p<0.05) from controls were noted in the atrazine test
concentrations below:

Tissue
tested Glycogen Total protein Lipids Cholesterol Triglycerides Lipid
Peroxidation (ug/L) Gill 5, 10, 20 None 5, 10, 20 None 5, 10 5, 10, 20 Liver 5, 10, 20 5, 10, 20 5, 10, 20 5, 10, 20 5, 10, 20 5, 10, 20 Muscle 5, 10, 20 5, 10, 20 1 5, 10, 20 5, 10, 20 5, 10, 20 5, 10, 20

1 Significant difference only noted when compared to control group sacrificed at 7 days.No significance differences were noted in weight or survival of atrazine treated animals as compared to controls.

Description of Use in Document: Qualitative. This study is of su fficient quality for inclusion in
risk assessment.

Rationale for Use: The study provides information on sublethal effects of atrazine on biochemical parameters as well as growth and survival in bullfrog tadpoles.

Limitations of the Study: Nominal concentrations are only reported; there is no inclusion of measured concentrations in control or treatment groups.

Reported water quality parameters were dissolved oxygen, pH and temperature. No water renewal was noted during the 7 day treatment period. Constant aeration was reported.

Reviewer: Colleen M. Rossmeisl, DVM; ERB3, Environmental Fate and Effects Division 

### COLLEEN ROSSMEISL Digitally signed by COLLEEN
ROSSMEISL DN: c=US, o=U.S. Government, ou=USEPA, ou=Staff, cn=COLLEEN ROSSMEISL, dnQualifier=0000069649
Date: 2016.04.07 17:56:35 -04'00'