Appendix 2 Open Literature Review Summaries for Malathion
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The survivability effects on tadpoles treated with combinations of malathion and cypermethrin are presented in Fig. 3 (copied without alteration from Nataraj et al. 2012). The survivability from the four combination treatments was reduced compared to the malathion only treatments. Based on combination treatments, a statistically significant reduction in survivability of 19.89% was observed at the constant 25 µg/L cypermethrin concentration with increasing malathion concentrations. For combinations using 50 µg/L cypermethrin and increasing malathion concentrations, the survivability reduction was significant at 71.33%.
On Day 145, the test was terminated when >80% of tadpoles in the controls had metamorphosed into froglets. The percent of survival, proportion of un-emerged tadpoles, and proportion of froglets emerged are presented in Table 1 (copied without alteration from Nataraj et al. 2012). The median time of emergence of tadpoles is presented as boxplot in Fig 4. (copied without alteration from Nataraj et al. 2012). For all treated groups excluding the 250 µg/L malathion, the metamorphosis of tadpoles into froglets was delayed and extended up to 130th day and only 20-45% of the surviving tadpoles emerged as froglets. 
Conclusions (EDSP List 1 Chemicals): The study author concluded the sublethal and environmentally realistic concentrations of malathion and cypermethrin reduces survivability and prolongs metamorphosis of surviving tadpoles. This can result in long term consequences on frog populations. Classification (EDSP List 1 Chemicals): Given that the test compounds were formulations, they were not used in the Weight of Evidence for either chemical. Other Risk Assessments: The study is of sufficient quality to include qualitatively in the risk assessment. The test methods and statistical analyses were described adequately for this article to be used descriptively in the risk assessment. However, the following study limitations prevent the article from being classified quantitatively: The individual raw data for test endpoints were not provided. No contaminant testing information was provided for the rice paddies where animals were collected for testing or for the test water. 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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