Data taken from US EPA (2015), p. 19 and 23.

NAFTA_SOP_2015

Format

2 datasets with observations on the following variables.

name

a factor containing the name of the observed variable

time

a numeric vector containing time points

value

a numeric vector containing concentrations

Source

NAFTA (2011) Guidance for evaluating and calculating degradation kinetics in environmental media. NAFTA Technical Working Group on Pesticides https://www.epa.gov/pesticide-science-and-assessing-pesticide-risks/guidance-evaluating-and-calculating-degradation accessed 2019-02-22

US EPA (2015) Standard Operating Procedure for Using the NAFTA Guidance to Calculate Representative Half-life Values and Characterizing Pesticide Degradation https://www.epa.gov/pesticide-science-and-assessing-pesticide-risks/standard-operating-procedure-using-nafta-guidance

Examples

nafta_evaluation <- nafta(NAFTA_SOP_Appendix_D, cores = 1)
#> Warning: Calculation of the Jacobian failed for the cost function of the untransformed model. #> No t-test results will be available
#> The SFO model is rejected as S_SFO is equal or higher than the critical value S_c
#> The representative half-life of the IORE model is longer than the one corresponding
#> to the terminal degradation rate found with the DFOP model.
#> The representative half-life obtained from the DFOP model may be used
print(nafta_evaluation)
#> Sums of squares: #> SFO IORE DFOP #> 1378.6832 615.7730 517.8836 #> #> Critical sum of squares for checking the SFO model: #> [1] 717.4598 #> #> Parameters: #> $SFO #> Estimate Pr(>t) Lower Upper #> parent_0 83.7558 8.08e-15 76.92822 90.58328 #> k_parent_sink 0.0017 7.45e-05 0.00111 0.00262 #> #> $IORE #> Estimate Pr(>t) Lower Upper #> parent_0 9.69e+01 NA 8.75e+01 1.06e+02 #> k__iore_parent_sink 8.40e-14 NA 1.09e-19 6.47e-08 #> N_parent 6.68e+00 NA 3.54e+00 9.83e+00 #> #> $DFOP #> Estimate Pr(>t) Lower Upper #> parent_0 9.76e+01 4.44e-13 8.88e+01 1.06e+02 #> k1 4.24e-02 3.55e-02 1.41e-02 1.27e-01 #> k2 8.24e-04 2.06e-02 3.17e-04 2.14e-03 #> g 2.88e-01 1.31e-04 1.78e-01 4.30e-01 #> #> #> DTx values: #> DT50 DT90 DT50_rep #> SFO 407 1350 407 #> IORE 541 5190000 1560000 #> DFOP 429 2380 841 #> #> Representative half-life: #> [1] 841.4096
plot(nafta_evaluation)