Appendix 2 Open Literature Review Summaries for Malathion
Figure 4. The abundance of (
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- Figure 5. Changes in ( a) pH and ( b)
- Figure 6. Changes in biomass of trophic groups in the food web as a result of exposure to ( a) no pesticide (control), ( b) solvent control (ethanol) and ( i)
- Basal resources for the two types of algae. Figure 6 from Relyea 2009. Data Summary Table
- Effect Magnitude of Effect relative to controls Nominal Atrazine Concen-tration (µg/L)
- Time Weighted Average Atrazine Concentration from Day 0 to When Effect Occurred Did Recovery Occur – if so, when
- Description of Use in Document
- Primary Reviewer
- Task Assignment No. 4-14-2014 Study Type: Non-Guideline Citation
Figure 4. The abundance of (a) phytoplankton (measured as chlorophyll a concentration) and (b) periphyton (measured as dry biomass on a clay tile) over time in outdoor mesocosms exposed to no pesticides (control), solvent only (ethanol), five separate insecticides, five separate herbicides, and a mixture of all ten pesticides. Data are mean ± 1 SE on a log scale. Within each sample date, asterisks indicate treatments that are significantly different from the no-pesticide treatment (P < 0.05 using Fisher’s LSD test). For abbreviations, see Figure 1. Figure 4 from Relyea 2009. Abiotic Effects Tank water pH and dissolved oxygen were measured on days 10 and 35. There was not a significant difference between the atrazine treatment and the negative control (P > 0.05 using Fisher’s LSD test) for either pH or dissolved oxygen on either date (Figure 5). The ethanol control differed from the negative control on day 10 for both pH and dissolved oxygen but was similar to the negative control on day 35. 
Figure 5. Changes in (a) pH and (b) dissolved oxygen over time in outdoor mesocosms exposed to no pesticides (control), solvent only (ethanol), five separate insecticides, five separate herbicides, and a mixture of all ten pesticides. Data are mean ± 1 SE. Within each sample date, asterisks indicate treatments that are significantly different from the no-pesticide treatment (P < 0.05 using Fisher’s LSD test). For abbreviations, see Figure 1. Figure 5 from Relyea 2009. Overall Results Overall, based on the results of the study, the study author concluded that atrazine had no significant effect (P > 0.05 using Fisher’s LSD test) on the biomass of any of the trophic groups monitored in this outdoor mesocosm experiment. The only significant effect of atrazine treatment which was observed was the increase in mass at metamorphosis for gray tree frog tadpoles (P = 0.045). The study author reported that the mechanism for this effect was unclear. The overall effects of the controls and atrazine treatments on biomass of trophic groups in the food web are qualitatively illustrated in Figure 6. 
Figure 6. Changes in biomass of trophic groups in the food web as a result of exposure to (a) no pesticide (control), (b) solvent control (ethanol) and (i) atrazine. The size of the circle and font for each trophic group indicates the qualitative change in the biomass of that trophic group. R Basal resources for the two types of algae. Figure 6 from Relyea 2009. Data Summary Table:
1 Nominal concentration was 10 µg/L. Actual concentration (6.4 µg/L) was measured 1 hour after application. 2 Data analyzed was the average zooplankton abundance over two sampling dates (days 16 and 36). Reviewer Comments: No measurements were made to determine if atrazine and the other nine pesticides were present in the control tanks. The author states that the well water used for filling the tanks did not have detectable concentrations of any of the pesticides used in the study, although the data or time at which it was analyzed was not reported. In addition, it was not stated if there was chemical analysis for any of the pesticides in the pond water which was added to the tanks as the source of the planktonic biota. The author reports that the concentration of ethanol was 0.003% in the solvent control tanks and the tanks receiving a mixture of all ten pesticides but does not report if the concentration of ethanol in the atrazine-only treatment was also 0.003%. Description of Use in Document: Qualitative Rationale for Use: The study contributes to the weight of evidence regarding the potential for effects of atrazine on aquatic plant communities. Limitations of Study: The results have good applicability to mesocosms or natural aquatic systems because the experimental mesocosms were outdoors during testing and contained phytoplankton, periphyton, zooplankton, and two species of amphibians. Actual pesticide (atrazine) concentrations were not monitored throughout the experiment, although an initial measured value was reported. Control tanks were not analyzed for atrazine and the other nine pesticides tested. Additionally, it is unclear how much ethanol was added to atrazine-only treatment tanks. Primary Reviewer: Lisa Muto, M.S., Staff Scientist, Cambridge Environmental Inc Secondary Reviewer: Michael Lowit, Ph.D., Ecologist, EPA Tertiary Reviewer: Anita Pease, M.S., Senior Biologist, EPA Data Evaluation Record MALATHION; CYPERMETHRIN PC Codes 057701; 109704 EPA Contract No. EP10H001452 Task Assignment No. 4-14-2014 Study Type: Non-Guideline Citation: Nataraj, M.B. and Krishnamurthy, S.V. (2012). Effects of Combinations of Malathion and Cypermethrin on Survivability and Time of Metamorphosis of Tadpoles of Indian Cricket Frog (Fejervarya limnocharis). Journal of Environmental Science and Health. 47:67-73. Prepared for Environmental Fate and Effects Division Office of Pesticide Programs U.S. Environmental Protection Agency One Potomac Yard 2777 S. Crystal Drive Arlington, VA 22202 Prepared by Dynamac Corporation 1910 Sedwick Road, Building 100, Suite B Durham, NC 27713
Directory: pesticides -> nas -> final final -> Appendix 1-10: Summary of Diazinon Monitoring Data nas -> Description of revision final -> Appendix 2 Chlorpyrifos Species Sensitivity Distribution Analysis for Fish Download 6.04 Mb. Share with your friends:
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