For the preparation of this report a long process was initiated since 2017 (Figure 1). In conducting this assessment, authors gathered publicly available information from a broad range of sources, including reports from international organizations, regional and national agencies and environmental organizations, and scientific literature. The literature search and review was carried out through multiple means, including but not limited to systematic search on different databases (Scopus, Science Direct and Google Scholar), Internet searches, telephone interviews and email correspondence. This report also complements existing relevant data collected during the last decade by the leading organizations (FAO, 2018b; FAO and ITPS, 2015; Rodríguez Eugenio, McLaughlin and Pennock, 2018).
For the regional assessment of soil pollution sources and status, two methodologies where used. A questionnaire, developed by the leading FAO’s GSP and its ITPS, was sent to countries through the GSP Focal Points and partners’ networks as well as UNEP membership. The questionnaire was conducted by use of a commercially available online survey tool (Google Form). It served to gather information about national and regional legislations, the main polluting activities as perceived by the governments, existing data on soil pollution in inventories and soil monitoring systems as well as monitoring systems related to human health. Case studies were also collected through the questionnaire. Three reminders were sent to the national focal points not responding to the questionnaire, and it was also promoted in every event organized by the GSP as well as during the UNEA4 side event on soil pollution. To overcome language problems, the questionnaire was translated into Spanish, French and Russian. Country responses were sent to the GSP Secretariat, which processed and analysed the information. The lack of Internet access in several countries was resolved by sending the questionnaire in Word format to the focal points who requested it, and subsequently the answers were entered into the online survey tool.
Given the lack of soil pollution data, the information provided by the countries was compared with the available scientific literature through a triangulation process to ensure the robustness and completeness of the information collected by the two processes.
For many aspects related to soil pollution, including sources and contaminants and their national and regional distribution, very limited information existed to support this study. It is for this reason that in some cases differences can be observed in the detail of the information presented. In general, only the main sources of pollution and the major contaminants associated with them have been analysed, which does not mean that other sources and contaminants are not present in the region or are not significant in a specific country within it.
Despite the initial proposal to hold regional workshops to present and discuss the results, the time frame and funding available meant that only one online consultation could be held with the Regional Soil Partnerships, which were part of the peer review process for this report. The main findings of this report and proposals for future action were presented during the GSP Plenary Assembly in 2020, so that all participating national focal points and GSP partners had the opportunity to provide their comments and proposals.
To ensure that the information contained in this report is accurate, complete and unbiased, an Editorial Board was established. Members of the ITPS, representatives of the Regional Soil Partnerships, internationally recognized experts and members of the leading UN agencies composed the Editorial Board. All chapters of this report were peer-reviewed by known experts and comments and corrections were incorporated in the final text.