This data set contains:

1) Preprint of the manuscript: Citizen-science data reveal drivers of PFAS variability in backyard chicken eggs

2) Replication data pfas_Masked.rdata: an R-workspace which contains the following elements: a) pfas - The PFAS lab-measurements, including different explanatory variables used in the model fitting, such as information on husbandry conditions.This data has been anonymised by adding a substantial amount of noise to the latitude (lat) and longitude (lng) coordinates, in order to remove any personal information. To use the original data collected on pfasinkaart.nl, a request can be sent to dreas@pfasinkaart.nl. b) pred_grid - A prediction grid that can be used for spatial plotting of model results.
c) ch: The coordinates of Chemours in Dordrecht. d: xy: A spatial point grid which has been linked to land-cover data and which is used for generating the spatial plots. e: crs.sed - the CRS (Coordinate Reference System) of the soil class data.
f: latlon.crs - the CRS of WGS84 (latitude, longitude) projection. g: RD.crs - the CRS of the Rijksdriehoek/Amersfoort projection.

3) pfas_Masked.csv: A csv file of the pfas data.frame as also contained in pfas_Masked.rdata.

4) R_Data_preparation_2026_03_11.qmd: A Quarto file showing all the steps used to process the data and generate an anonymised dataset that can be used for subsequent model fitting and plotting. Note this code can only be run after requesting the raw non-anonymised data from dreas@pfasinkaart.nl.

5) A PDF of Data_preparation_2026_03_11.qmd

6) R_Model_Fitting_2026_03_12.qmd: A Quarto file with R-code for model fitting

7) R_Model_Fitting_2026_03_12.pdf: A PDF of R_Model_Fitting_2026_03_12.qmd

8) R_results and plotting_2026_03_12b.qmd: A Quarto file with R-code to generate the results and produce manuscript figures

9) R_results and plotting_2026_03_12b.pdf: A PDF of R_results and plotting_2026_03_12b.qmd

R, 4.4.2 (2024-10-31 ucrt)