From 3a579d87820ccbec514f1be5eb090e874fd87eec Mon Sep 17 00:00:00 2001 From: Johannes Ranke Date: Tue, 22 Dec 2015 19:32:54 +0100 Subject: EFSA 2015 tier 1 PEC soil, clean up, add static docs --- pkg/man/PEC_soil.Rd | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 88 insertions(+), 5 deletions(-) (limited to 'pkg/man/PEC_soil.Rd') diff --git a/pkg/man/PEC_soil.Rd b/pkg/man/PEC_soil.Rd index 2433ecc..c0b5201 100644 --- a/pkg/man/PEC_soil.Rd +++ b/pkg/man/PEC_soil.Rd @@ -5,7 +5,10 @@ \title{Calculate predicted environmental concentrations in soil} \usage{ PEC_soil(rate, rate_units = "g/ha", interception = 0, mixing_depth = 5, - bulk_density = 1.5, PEC_units = "mg/kg") + PEC_units = "mg/kg", PEC_pw_units = "mg/L", interval = NA, + n_periods = Inf, tillage_depth = 20, chent = NA, DT50 = NA, + Koc = NA, Kom = Koc/1.724, t_avg = 0, scenarios = c("default", + "EFSA_2015"), porewater = FALSE) } \arguments{ \item{rate}{Application rate in units specified below} @@ -16,21 +19,101 @@ PEC_soil(rate, rate_units = "g/ha", interception = 0, mixing_depth = 5, \item{mixing_depth}{Mixing depth in cm} -\item{bulk_density}{Bulk density of the soil. Defaults to 1.5 kg/L, or 1500 kg/m3} - \item{PEC_units}{Requested units for the calculated PEC. Only mg/kg currently supported} + +\item{PEC_pw_units}{Only mg/L currently supported} + +\item{interval}{Period of the deeper mixing, defaults to 365, which is a year if +rate units are in days} + +\item{n_periods}{Number of periods to be considered for long term PEC calculations} + +\item{tillage_depth}{Periodic (see interval) deeper mixing in cm} + +\item{chent}{An optional chent object holding substance specific information. Can +also be a name for the substance as a character string} + +\item{DT50}{If specified, overrides soil DT50 endpoints from a chent object +If DT50 is not specified here and not available from the chent object, zero +degradation is assumed} + +\item{Koc}{If specified, overrides Koc endpoints from a chent object} + +\item{Kom}{Calculated from Koc by default, but can explicitly be specified +as Kom here} + +\item{t_avg}{Averaging times for time weighted average concentrations} + +\item{scenarios}{If this is 'default', the DT50 will be used without correction +and soil properties as specified in the REACH guidance (R.16, Table +R.16-9) are used for porewater PEC calculations. If this is "EFSA_2015", +the DT50 is taken to be a modelling half-life at 20°C and pF2 (for when +'chents' is specified, the DegT50 with destination 'PECgw' will be used), +and corrected using an Arrhenius activation energy of 65.4 kJ/mol. Also +model and scenario adjustment factors from the EFSA guidance are used.} + +\item{porewater}{Should equilibrium porewater concentrations be estimated +based on Kom and the organic carbon fraction of the soil instead of total +soil concentrations? Based on equation (7) given in the PPR panel opinion +(EFSA 2012, p. 24) and the scenarios specified in the EFSA guidance (2015, +p. 13).} } \value{ The predicted concentration in soil } \description{ -This is a basic, vectorised form of a simple calculation of a contaminant -concentration in bulk soil based on complete, instantaneous mixing. +This is a basic calculation of a contaminant concentration in bulk soil +based on complete, instantaneous mixing. If an interval is given, an +attempt is made at calculating a long term maximum concentration using +the concepts layed out for example in the PPR panel opinion (EFSA 2012). +} +\details{ +This assumes that the complete load to soil during the time specified by +'interval' (typically 365 days) is dosed at once. As in the PPR panel +opinion cited below (PPR panel 2012), only temperature correction using the +Arrhenius equation is performed. + +Total soil and porewater PEC values for the scenarios as defined in the EFSA +guidance (2015, p. 13) can easily be calculated. +} +\note{ +If temperature information is available in the selected scenarios, as + e.g. in the EFSA scenarios, the DT50 for groundwater modelling + (destination 'PECgw') is taken from the chent object, otherwise the DT50 + with destination 'PECsoil'. } \examples{ PEC_soil(100, interception = 0.25) + +# This is example 1 starting at p. 79 of the EFSA guidance (2015) +PEC_soil(1000, interval = 365, DT50 = 250, t_avg = c(0, 21), + scenarios = "EFSA_2015") +PEC_soil(1000, interval = 365, DT50 = 250, t_av = c(0, 21), + Kom = 1000, scenarios = "EFSA_2015", porewater = TRUE) + +# The following is from example 4 starting at p. 85 of the EFSA guidance (2015) +# Metabolite M2 +# Calculate total and porewater soil concentrations for tier 1 scenarios +# Relative molar mass is 100/300, formation fraction is 0.7 * 1 +results_pfm <- PEC_soil(100/300 * 0.7 * 1 * 1000, interval = 365, DT50 = 250, t_avg = c(0, 21), + scenarios = "EFSA_2015") +results_pfm_pw <- PEC_soil(100/300 * 0.7 * 1000, interval = 365, DT50 = 250, t_av = c(0, 21), + Kom = 100, scenarios = "EFSA_2015", porewater = TRUE) } \author{ Johannes Ranke } +\references{ +EFSA Panel on Plant Protection Products and their Residues (2012) + Scientific Opinion on the science behind the guidance for scenario + selection and scenario parameterisation for predicting environmental + concentrations of plant protection products in soil. \emph{EFSA Journal} + \bold{10}(2) 2562, doi:10.2903/j.efsa.2012.2562 + + EFSA (European Food Safety Authority) (2015) EFSA guidance document for + predicting environmental concentrations of active substances of plant + protection products and transformation products of these active substances + in soil. \emph{EFSA Journal} \bold{13}(4) 4093 + doi:10.2903/j.efsa.2015.4093 +} -- cgit v1.2.1