1. Introduction
Pesticides are used in order to protect valuable assets such as crops
and human health against potential adverse impacts from pest, insects,
weeds, and pathogens. As such, pesticide use is a major foundation of
the agricultural intensification observed since the middle of the 20th
century (Masiá et al., 2014; Silva et al., 2019). The global amount of
pesticides used has been estimated at approximately 6 billion pounds in
2011 and 2012 (USEPA, 2017). This amount keeps increasing, particularly
in low and middle income countries (Akter et al., 2018; Balmer et al.,
2019; Phillips McDouglas Agribusiness Intelligence, 2019). The extensive
and improper use of pesticides can also have negative impacts, e.g. on
the crop itself, on human health and on ecosystems, especially in
aquatic environments (Verger and Boobis, 2013; Tsaboula et al., 2016;
Kapsi et al., 2019). In order to prevent such negative impacts, the
marketing and use of pesticides are strictly regulated in most
countries.
Appropriate management of pesticides requires information on the types
and amounts of pesticides used. Eurostat (2008) advocates collection of
usage statistics in particular for: (1) provision of annual usage
estimates in countries; (2) monitoring changes over time (Coupe and
Capel, 2016); (3) environmental protection; (4) consumer protection:
providing information for residue monitoring; (5) operator protection
(improving or optimizing use); (6) monitoring the potential movement of
pesticides into water; (7) policy advise during review programs
(reviewing use of existing pesticides); (8) providing information for
approval of new pesticides. However, the public availability of
pesticide use data is generally scarce, i.e. because of proprietary data
issues, poor registration, lacking regulations or the costs
involved. Eurostat (2008) stipulates that the cost benefits for
gathering actual usage statistics far outstrip the investments. An
excellent example of collecting usage data is the Pesticide Use
Reporting Program in California in which farmers are required to monthly
report pesticide use (California Department of Pesticide Regulation,
2000).
Pesticide use data can take the form of sales data and usage data. Sales
data are more generic and cannot be related directly to the actual use
in time and space since they do not provide details on crop, timing,
spatial variation and the dose applied (Eurostat, 2008). These details
are needed in order to estimate pesticide emissions, model surface water
contamination, estimate risks, set priorities and identify mitigation
measures (Herrero-Hernández et al., 2017; Bidleman et al., 2002;
Konstantinou et al., 2006; Al-Khazrajy & Boxall, 2016; Van Gils et al.,
2019). Usage data do provide the kind of detail needed to satisfy this
kind of governance, research and management needs. Unfortunately, usage
data is typically unavailable or difficult to obtain for all crops
produced in an area, particularly in low and middle income countries
like Indonesia (Mariyono et al., 2018).
The aim of the present study was to determine the pesticide use by
farmers in the Upper Citarum River Basin (UCRB) and make the data open
access. The study was initiated to obtain input data required for
predicting surface water concentrations of pesticides in the UCRB. In
order to acquire the data, a survey among 174 farmers was conducted,
focusing on the types and amounts of pesticides used on major crop
types.